Caspase-3-independent pathways proceeding in bystander effect of HSV-tk/GCV system

NASA Astrophysics Data System (ADS)

Lin, Juqiang; Ma, Yan; Zeng, Shaoqun; Zhang, Zhihong

2008-02-01

HSV-tk/GCV system, which is the virus-directed enzyme/prodrug therapy of herpes simplex virus (HSV) thymidine kinase (tk) gene / the anti-viral reagent ganciclovir (GCV), is one of the promising approaches in the rapidly growing area of gene therapy. As gene therapy of cancer such as suicide gene therapy has entered the clinic, another therapy effect which is called 'bystander effect' was reported. Bystander effect can lead to killing of non-transduced tumor cells in the immediate vicinity of GCV-treated HSV-TK-positive cells. Now the magnitude of 'bystander effect' is an essential factor for this anti-tumor approach in vivo. However, the mechanism which HSV-tk/ACV brings "bystander effect" is poorly understood. In this study, we monitor the activation of caspase-3 in HSV-tk/GCV system by a FRET probe CD3, a FRET-based indicator for activity of caspase3, which is composed of an enhanced cyan fluorescent protein, a caspase-sensitive linker, and a red fluorescent protein from Discosoma with efficient maturation property. Through application of CD3 we have visualized the activation of caspase-3 in tk gene positive human adenoid cystic carcinoma (ACC-M) cells but not in bystander effect of HSV-tk/GCV system induced by GCV. This finding provides needed information for understanding the mechanisms by which suicide gene approaches actually kill cancer cells, and may prove to be helpful for the clinical treatment of cancers.

Collective helping and bystander effects in coevolving helping networks.

PubMed

Jo, Hang-Hyun; Lee, Hyun Keun; Park, Hyunggyu

2010-06-01

We study collective helping behavior and bystander effects in a coevolving helping network model. A node and a link of the network represents an agent who renders or receives help and a friendly relation between agents, respectively. A helping trial of an agent depends on relations with other involved agents and its result (success or failure) updates the relation between the helper and the recipient. We study the network link dynamics and its steady states analytically and numerically. The full phase diagram is presented with various kinds of active and inactive phases and the nature of phase transitions are explored. We find various interesting bystander effects, consistent with the field study results, of which the underlying mechanism is proposed.

Leverage Between the Buffering Effect and the Bystander Effect in Social Networking.

PubMed

Chiu, Yu-Ping; Chang, Shu-Chen

2015-08-01

This study examined encouraged and inhibited social feedback behaviors based on the theories of the buffering effect and the bystander effect. A system program was used to collect personal data and social feedback from a Facebook data set to test the research model. The results revealed that the buffering effect induced a positive relationship between social network size and feedback gained from friends when people's social network size was under a certain cognitive constraint. For people with a social network size that exceeds this cognitive constraint, the bystander effect may occur, in which having more friends may inhibit social feedback. In this study, two social psychological theories were applied to explain social feedback behavior on Facebook, and it was determined that social network size and social feedback exhibited no consistent linear relationship.

Photon hormesis deactivates alpha-particle induced bystander effects between zebrafish embryos

NASA Astrophysics Data System (ADS)

Ng, C. Y. P.; Cheng, S. H.; Yu, K. N.

2017-04-01

In the present work, we studied the effects of low-dose X-ray photons on the alpha-particle induced bystander effects between embryos of the zebrafish, Danio rerio. The effects on the naive whole embryos were studied through quantification of apoptotic signals (amounts of cells undergoing apoptosis) at 24 h post fertilization (hpf) using vital dye acridine orange staining, followed by counting the stained cells under a fluorescent microscope. We report data showing that embryos at 5 hpf subjected to a 4.4 mGy alpha-particle irradiation could release a stress signal into the medium, which could induce bystander effect in partnered naive embryos sharing the same medium. We also report that the bystander effect was deactivated when the irradiated embryos were subjected to a concomitant irradiation of 10 or 14 mGy of X-rays, but no such deactivation was achieved if the concomitant X-ray dose dropped to 2.5 or 5 mGy. In the present study, the significant drop in the amount of apoptotic signals on the embryos having received 4.4 mGy alpha particles together X-rays irradiation from 2.5 or 5 mGy to 10 or 14 mGy, together with the deactivation of RIBE with concomitant irradiation of 10 or 14 mGy of X-rays supported the participation of photon hormesis with an onset dose between 5 and 10 mGy, which might lead to removal of aberrant cells through early apoptosis or induction of high-fidelity DNA repair. As we found that photons and alpha particles could have opposite biological effects when these were simultaneously irradiated onto living organisms, these ionizing radiations could be viewed as two different environmental stressors, and the resultant effects could be regarded as multiple stressor effects. The present work presented the first study on a multiple stressor effect which occurred on bystander organisms. In other words, this was a non-targeted multiple stressor effect. The photon hormesis could also explain some failed attempts to observe neutron-induced bystander

The Bystander-Effect: A Meta-Analytic Review on Bystander Intervention in Dangerous and Non-Dangerous Emergencies

ERIC Educational Resources Information Center

Fischer, Peter; Krueger, Joachim I.; Greitemeyer, Tobias; Vogrincic, Claudia; Kastenmuller, Andreas; Frey, Dieter; Heene, Moritz; Wicher, Magdalena; Kainbacher, Martina

2011-01-01

Research on bystander intervention has produced a great number of studies showing that the presence of other people in a critical situation reduces the likelihood that an individual will help. As the last systematic review of bystander research was published in 1981 and was not a quantitative meta-analysis in the modern sense, the present…

[Radiation-induced bystander effect: the important part of ionizing radiation response. Potential clinical implications].

PubMed

Wideł, Maria; Przybyszewski, Waldemar; Rzeszowska-Wolny, Joanna

2009-08-18

It has long been a central radiobiological dogma that the damaging effects of ionizing radiation, such as cell death, cytogenetic changes, apoptosis, mutagenesis, and carcinogenesis, are the results of the direct ionization of cell structures, particularly DNA, or indirect damage via water radiolysis products. However, several years ago attention turned to a third mechanism of radiation, termed the "bystander effect" or "radiation-induced bystander effect" (RIBE). This is induced by agents and signals emitted by directly irradiated cells and manifests as a lowering of survival, cytogenetic damage, apoptosis enhancement, and biochemical changes in neighboring non-irradiated cells. The bystander effect is mainly observed in in vitro experiments using very low doses of alpha particles (range; mGy, cGy), but also after conventional irradiation (X-rays, gamma rays) at low as well as conventional doses. The mechanisms responsible for the bystander effect are complex and still poorly understood. It is believed that molecular signals released from irradiated cells induce different signaling ways in non-irradiated neighboring cells, leading to the observed events. The molecular signals may be transmitted through gap junction intercellular communication and through a medium transfer mechanism. The nature of these transmitted factors are diverse, and still not definitely established. It seems that RIBE may have important clinical implications for health risk associated with radiation exposure. Potentially, this effect may have important implications in the creation of whole-body or localized side effects in tissues beyond the irradiation field and also in low-dose radiological and radioisotope diagnostics. Factors emitted by irradiated cells may result in the risk of genetic instability, mutations, and second primary cancer induction. They might also have their own part in inducing and extending post-radiation side effects in normal tissue. The bystander effect may be a

Chemotherapy-induced bystander effect in response to several chloroethylnitrosoureas: an origin independent of DNA damage?

PubMed

Merle, Patrick; Morvan, Daniel; Caillaud, Denis; Demidem, Aicha

2008-01-01

Chloroethylnitrosourea (CENU) chemotherapy is used for the treatment of melanoma tumors. The main mechanism of action of this anticancer agent is via DNA damage. We recently showed in murine experiments using a parental double B16 melanoma tumor model that, after treatment of primary tumors with cystemustine (CENU agent), untreated secondary tumors exhibited growth inhibition and metabolism disorders. The response of secondary untreated tumor was called the chemotherapy-induced bystander effect. To see whether chemotherapy-induced bystander effects were induced with other members of the CENU family, we compared three CENU(s) used in melanoma treatment: cystemustine, carmustine and fotemustine. Our results demonstrate that fotemustine, like cystemustine, but not carmustine induced a protective effect against secondary untreated tumors including alterations in phospholipid derivative and glutathione which are the metabolic signature of the bystander effect. From these data we may conclude that DNA damage to the primary tumor is not sufficient to explain chemotherapy-induced bystander effects.

Investigation of the Bystander Effect in School Bullying: Comparison of Experiential, Psychological and Situational Factors

ERIC Educational Resources Information Center

Song, Jiyeon; Oh, Insoo

2017-01-01

The purpose of this study was to investigate whether the "bystander effect" known to occur in emergency situations is effective in bullying situations through examination of the individual experiences of 467 middle- and high-school students. While the bystander effect was not found to be valid in bullying situations, there were…

The Role of DNA Methylation Changes in Radiation-Induced Bystander Effects in cranial irradiated Mice

NASA Astrophysics Data System (ADS)

Zhang, Meng; Sun, Yeqing; Xue, Bei; Wang, Xinwen; Wang, Jiawen

2016-07-01

Heavy-ion radiation could lead to bystander effect in neighboring non-hit cells by signals released from directly-irradiated cells. The exact mechanisms of radiation-induced bystander effect in distant organ remain obscure, yet accumulating evidence points to the role of DNA methylation changes in bystander effect. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male Balb/c and C57BL mice were cranial exposed to 40, 200, 2000mGy dose of carbon heavy-ion radiation, while the rest of the animal body was shielded. The γH2AX foci as the DNA damage biomarker in directly irradiation organ ear and the distant organ liver were detected on 0, 1, 2, 6, 12 and 24h after radiation, respectively. Methylation-sensitive amplifcation polymorphism (MSAP) was used to monitor the level of polymorphic genomic DNA methylation changed with dose and time effects. The results show that cranial irradiated mice could induce the γH2AX foci and genomic DNA methylation changes significantly in both the directly irradiation organ ear and the distant organ liver. The percent of DNA methylation changes were time-dependent and tissue-specific. Demethylation polymorphism rate were highest separately at 1 h in 200 mGy and 6 h in 2000 mGy after irradiation in ear. The global DNA methylation changes tended to occur in the CG sites. We also found that the numbers of γH2AX foci and the genomic methylation changes of heavy-ion radiation-induced bystander effect in liver could be obvious 1 h after radiation and achieved the maximum at 6 h, while the changes could recover gradually at 12 h. The results suggest that mice head exposed to heavy-ion radiation can induce damage and methylation pattern changed in both directly radiation organ ear and distant organ liver. Moreover, our findings are important to understand the molecular mechanism of radiation induced bystander effects in vivo. Keywords: Heavy-ion radiation; Bystander effect; DNA methylation; γH2

Bystander effects of ionizing radiation can be modulated by signaling amines

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

Poon, R.C.C.; Agnihotri, N.; Seymour, C.

2007-10-15

Actual risk and risk management of exposure to ionizing radiation are among the most controversial areas in environmental health protection. Recent developments in radiobiology especially characterization of bystander effects have called into question established dogmas and are thought to cast doubt on the scientific basis of the risk assessment framework, leading to uncertainty for regulators and concern among affected populations. In this paper we test the hypothesis that small signaling molecules widely used throughout the animal kingdom for signaling stress or environmental change, such as 5-Hydroxytryptamine (5-HT, serotonin), L-DOPA, glycine or nicotine are involved in bystander signaling processes following ionizingmore » radiation exposure. We report data which suggest that nano to micromolar concentrations of these agents can modulate bystander-induced cell death. Depletion of 5-HT present in tissue culture medium, occurred following irradiation of cells. This suggested that 5-HT might be bound by membrane receptors after irradiation. Expression of 5-HT type 3 receptors which are Ca{sup 2+} ion channels was confirmed in the cells using immunocytochemistry and receptor expression could be increased using radiation or 5-HT exposure. Zofran and Kitryl, inhibitors of 5-HT type 3 receptors, and reserpine a generic serotonin antagonist block the bystander effect induced by radiation or by serotonin. The results may be important for the mechanistic understanding of how low doses of radiation interact with cells to produce biological effects.« less

RCT Testing Bystander Effectiveness to Reduce Violence.

PubMed

Coker, Ann L; Bush, Heather M; Cook-Craig, Patricia G; DeGue, Sarah A; Clear, Emily R; Brancato, Candace J; Fisher, Bonnie S; Recktenwald, Eileen A

2017-05-01

Bystander-based programs have shown promise to reduce interpersonal violence at colleges, yet limited rigorous evaluations have addressed bystander intervention effectiveness in high schools. This study evaluated the Green Dot bystander intervention to reduce sexual violence and related forms of interpersonal violence in 26 high schools over 5 years. A cluster RCT was conducted. Kentucky high schools were randomized to intervention or control (wait list) conditions. Green Dot-trained educators conducted schoolwide presentations and recruited student popular opinion leaders to receive bystander training in intervention schools beginning in Year 1. The primary outcome was sexual violence perpetration, and related forms of interpersonal violence victimization and perpetration were also measured using anonymous student surveys collected at baseline and annually from 2010 to 2014. Because the school was the unit of analysis, violence measures were aggregated by school and year and school-level counts were provided. A total of 89,707 students completed surveys. The primary, as randomized, analyses conducted in 2014-2016 included linear mixed models and generalized estimating equations to examine the condition-time interaction on violence outcomes. Slopes of school-level totals of sexual violence perpetration (condition-time, p<0.001) and victimization (condition-time, p<0.001) were different over time. During Years 3-4, when Green Dot was fully implemented, the mean number of sexual violent events prevented by the intervention was 120 in Intervention Year 3 and 88 in Year 4. For Year 3, prevalence rate ratios for sexual violence perpetration in the intervention relative to control schools were 0.83 (95% CI=0.70, 0.99) in Year 3 and 0.79 (95% CI=0.67, 0.94) in Year 4. Similar patterns were observed for sexual violence victimization, sexual harassment, stalking, and dating violence perpetration and victimization. Implementation of Green Dot in Kentucky high schools

RCT Testing Bystander Effectiveness to Reduce Violence

PubMed Central

Coker, Ann L.; Bush, Heather M.; Cook-Craig, Patricia G.; DeGue, Sarah A.; Clear, Emily R.; Brancato, Candace J.; Fisher, Bonnie S.; Recktenwald, Eileen A.

2017-01-01

Introduction Bystander-based programs have shown promise to reduce interpersonal violence at colleges, yet limited rigorous evaluations have addressed bystander intervention effectiveness in high schools. This study evaluated the Green Dot bystander intervention to reduce sexual violence and related forms of interpersonal violence in 26 high schools over 5 years. Design A cluster RCT was conducted. Setting/participants Kentucky high schools were randomized to intervention or control (wait list) conditions. Intervention Green Dot–trained educators conducted schoolwide presentations and recruited student popular opinion leaders to receive bystander training in intervention schools beginning in Year 1. Main outcome measures The primary outcome was sexual violence perpetration, and related forms of interpersonal violence victimization and perpetration were also measured using anonymous student surveys collected at baseline and annually from 2010 to 2014. Because the school was the unit of analysis, violence measures were aggregated by school and year and school-level counts were provided. Results A total of 89,707 students completed surveys. The primary, as randomized, analyses conducted in 2014–2016 included linear mixed models and generalized estimating equations to examine the condition–time interaction on violence outcomes. Slopes of school-level totals of sexual violence perpetration (condition–time, p<0.001) and victimization (condition time, p<0.001) were different over time. During Years 3–4, when Green Dot was fully implemented, the mean number of sexual violent events prevented by the intervention was 120 in Intervention Year 3 and 88 in Year 4. For Year 3, prevalence rate ratios for sexual violence perpetration in the intervention relative to control schools were 0.83 (95% CI=0.70, 0.99) in Year 3 and 0.79 (95% CI=0.67, 0.94) in Year 4. Similar patterns were observed for sexual violence victimization, sexual harassment, stalking, and dating

Bystander Effect Induced by Electroporation is Possibly Mediated by Microvesicles and Dependent on Pulse Amplitude, Repetition Frequency and Cell Type.

PubMed

Prevc, Ajda; Bedina Zavec, Apolonija; Cemazar, Maja; Kloboves-Prevodnik, Veronika; Stimac, Monika; Todorovic, Vesna; Strojan, Primoz; Sersa, Gregor

2016-10-01

Bystander effect, a known phenomenon in radiation biology, where irradiated cells release signals which cause damage to nearby, unirradiated cells, has not been explored in electroporated cells yet. Therefore, our aim was to determine whether bystander effect is present in electroporated melanoma cells in vitro, by determining viability of non-electroporated cells exposed to medium from electroporated cells and by the release of microvesicles as potential indicators of the bystander effect. Here, we demonstrated that electroporation of cells induces bystander effect: Cells exposed to electric pulses mediated their damage to the non-electroporated cells, thus decreasing cell viability. We have shown that shedding microvesicles may be one of the ways used by the cells to mediate the death signals to the neighboring cells. The murine melanoma B16F1 cell line was found to be more electrosensitive and thus more prone to bystander effect than the canine melanoma CMeC-1 cell line. In B16F1 cell line, bystander effect was present above the level of electropermeabilization of the cells, with the threshold at 800 V/cm. Furthermore, with increasing electric field intensities and the number of pulses, the bystander effect also increased. In conclusion, electroporation can induce bystander effect which may be mediated by microvesicles, and depends on pulse amplitude, repetition frequency and cell type.

Effects of group status and victim sex on female bystanders' responses to a potential party rape.

PubMed

Katz, Jennifer; Colbert, Samuel; Colangelo, Liane

2015-01-01

This research examined bystander responses to 1 of 4 potential party rape scenarios. Undergraduate women (N = 249) imagined attending a party either alone or with three friends where a sober man led an intoxicated potential victim (either male or female) into a bedroom. After random assignment to conditions, participants reported on intent to help and barriers to helping the potential victim. In contrast to the classic bystander effect, bystanders in groups intended to offer more help than lone bystanders. Bystanders also intended to offer more help to potential female than male victims and experienced more barriers to helping male victims. Two of these barriers (lack of personal responsibility to help and identifying risk) explained the lower intentions to help potential male victims. Potential male victims were more likely than female victims to be perceived as gay, and bystanders reported the least intentions to help presumably gay men at risk.

Masculinity and Bystander Attitudes: Moderating Effects of Masculine Gender Role Stress

PubMed Central

Leone, Ruschelle M.; Parrott, Dominic J.; Swartout, Kevin M.; Tharp, Andra Teten

2018-01-01

Objective The purpose of the current study was to examine the bystander decision-making process as a mechanism by which men’s adherence to various dimensions of traditional masculinity is associated with their confidence to intervene in sexually aggressive events. Further, this study examined the stress men experience from their attempts to adhere to traditional male gender roles as a moderator of this mediational path. Method Participants (n = 252) completed measures of traditional masculinity, decisional balance (i.e., weighing the pros and cons) for intervening, masculine gender roles stress, and bystander efficacy. Results The belief that men must attain social status was associated with more confidence in men’s ability to intervene. This effect was mediated by greater perceived positive consequences for intervention among men high, but not low, in masculine gender role stress. The belief that men should be tough and aggressive was associated with greater perceived negative consequences for intervention and less confidence to intervene. The belief that men should not act in stereotypically feminine ways was directly associated with less confidence for intervention. Conclusions Findings highlight the importance of examining masculinity from a multidimensional perspective to better understand how adherence to various norms differentially influences bystander behavior. These findings may help to inform bystander intervention programming. PMID:29593932

Masculinity and Bystander Attitudes: Moderating Effects of Masculine Gender Role Stress.

PubMed

Leone, Ruschelle M; Parrott, Dominic J; Swartout, Kevin M; Tharp, Andra Teten

2016-01-01

The purpose of the current study was to examine the bystander decision-making process as a mechanism by which men's adherence to various dimensions of traditional masculinity is associated with their confidence to intervene in sexually aggressive events. Further, this study examined the stress men experience from their attempts to adhere to traditional male gender roles as a moderator of this mediational path. Participants ( n = 252) completed measures of traditional masculinity, decisional balance (i.e., weighing the pros and cons) for intervening, masculine gender roles stress, and bystander efficacy. The belief that men must attain social status was associated with more confidence in men's ability to intervene. This effect was mediated by greater perceived positive consequences for intervention among men high, but not low, in masculine gender role stress. The belief that men should be tough and aggressive was associated with greater perceived negative consequences for intervention and less confidence to intervene. The belief that men should not act in stereotypically feminine ways was directly associated with less confidence for intervention. Findings highlight the importance of examining masculinity from a multidimensional perspective to better understand how adherence to various norms differentially influences bystander behavior. These findings may help to inform bystander intervention programming.

Low Doses of Gamma-Irradiation Induce an Early Bystander Effect in Zebrafish Cells Which Is Sufficient to Radioprotect Cells

PubMed Central

Pereira, Sandrine; Malard, Véronique; Ravanat, Jean-Luc; Davin, Anne-Hélène; Armengaud, Jean; Foray, Nicolas; Adam-Guillermin, Christelle

2014-01-01

The term “bystander effect” is used to describe an effect in which cells that have not been exposed to radiation are affected by irradiated cells though various intracellular signaling mechanisms. In this study we analyzed the kinetics and mechanisms of bystander effect and radioadaptation in embryonic zebrafish cells (ZF4) exposed to chronic low dose of gamma rays. ZF4 cells were irradiated for 4 hours with total doses of gamma irradiation ranging from 0.01–0.1 Gy. In two experimental conditions, the transfer of irradiated cells or culture medium from irradiated cells results in the occurrence of DNA double strand breaks in non-irradiated cells (assessed by the number of γ-H2AX foci) that are repaired at 24 hours post-irradiation whatever the dose. At low total irradiation doses the bystander effect observed does not affect DNA repair mechanisms in targeted and bystander cells. An increase in global methylation of ZF4 cells was observed in irradiated cells and bystander cells compared to control cells. We observed that pre-irradiated cells which are then irradiated for a second time with the same doses contained significantly less γ-H2AX foci than in 24 h gamma-irradiated control cells. We also showed that bystander cells that have been in contact with the pre-irradiated cells and then irradiated alone present less γ-H2AX foci compared to the control cells. This radioadaptation effect is significantly more pronounced at the highest doses. To determine the factors involved in the early events of the bystander effect, we performed an extensive comparative proteomic study of the ZF4 secretomes upon irradiation. In the experimental conditions assayed here, we showed that the early events of bystander effect are probably not due to the secretion of specific proteins neither the oxidation of these secreted proteins. These results suggest that early bystander effect may be due probably to a combination of multiple factors. PMID:24667817

Ionizing radiation-induced bystander mutagenesis and adaptation: Quantitative and temporal aspects

PubMed Central

Zhang, Ying; Zhou, Junqing; Baldwin, Joseph; Held, Kathryn D; Prise, Kevin M; Redmond, Robert W.; Liber, Howard L.

2009-01-01

This work explores several quantitative aspects of radiation-induced bystander mutagenesis in WTK1 human lymphoblast cells. Gamma-irradiation of cells was used to generate conditioned medium containing bystander signals, and that medium was transferred onto naïve recipient cells. Kinetic studies revealed that it required up to one hour to generate sufficient signal to induce the maximal level of mutations at the thymidine kinase locus in the bystander cells receiving the conditioned medium. Furthermore, it required at least one hour of exposure to the signal in the bystander cells to induce mutations. Bystander signal was fairly stable in the medium, requiring 12–24 hours to diminish. Medium that contained bystander signal was rendered ineffective by a 4-fold dilution; in contrast a greater than 20-fold decrease in the cell number irradiated to generate a bystander signal was needed to eliminate bystander-induced mutagenesis. This suggested some sort of feedback inhibition by bystander signal that prevented the signaling cells from releasing more signal. Finally, an ionizing radiation-induced adaptive response was shown to be effective in reducing bystander mutagenesis; in addition, low levels of exposure to bystander signal in the transferred medium induced adaptation that was effective in reducing mutations induced by subsequent γ-ray exposures. PMID:19695271

I know what you did: The effects of interpersonal deviance on bystanders.

PubMed

Ferguson, Merideth; Barry, Bruce

2011-01-01

Using social information processing theory, we explore how interpersonally directed deviance affects work group members who observe or are aware of these insidious behaviors. In a field study, we find that indirect knowledge of work group member interpersonal deviance leads to subsequent interpersonal deviance of a focal individual. We also find that when work group cohesion is high, direct observation of deviance is more likely to result in subsequent bystander deviance. These findings add concretely to theory and research on the bystander effects of workplace deviance.

Radiation-induced bystander effect and adaptive response in mammalian cells

NASA Technical Reports Server (NTRS)

Zhou, H.; Randers-Pehrson, G.; Waldren, C. A.; Hei, T. K.

2004-01-01

Two conflicting phenomena, bystander effect and adaptive response, are important in determining the biological responses at low doses of radiation and have the potential to impact the shape of the dose-response relationship. Using the Columbia University charged-particle microbeam and the highly sensitive AL cell mutagenic assay, we show here that non-irradiated cells acquire mutagenesis through direct contact with cells whose nuclei have been traversed with a single alpha particle each. Pretreatment of cells with a low dose of X-rays four hours before alpha particle irradiation significantly decreased this bystander mutagenic response. Results from the present study address some of the fundamental issues regarding both the actual target and radiation dose effect and can contribute to our current understanding in radiation risk assessment. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Debriefing bystanders of out-of-hospital cardiac arrest is valuable.

PubMed

Møller, Thea Palsgaard; Hansen, Carolina Malta; Fjordholt, Martin; Pedersen, Birgitte Dahl; Østergaard, Doris; Lippert, Freddy K

2014-11-01

To explore the concept of debriefing bystanders after participating in an out-of-hospital cardiac arrest resuscitation attempt including (1) bystanders' most commonly addressed reactions after participating in a resuscitation attempt when receiving debriefing from medical dispatchers; (2) their perception of effects of receiving debriefing and (3) bystanders' recommendations for a systematic debriefing concept. Qualitative study based on telephone debriefing to bystanders and interviews with bystanders who received debriefing. Data was analyzed using the phenomenological approach. Six themes emerged from analysis of debriefing audio files: (1) identification of OHCA; (2) emotional and perceptual experience with OHCA; (3) collaboration with healthcare professionals; (4) patients outcome; (5) coping with the experience and (6) general reflections. When evaluating the concept, bystanders expressed positive short term effect of receiving debriefing and a retention of this effect after two months. Recommendations for a future debriefing concept were given. Debriefing by emergency medical dispatchers to OHCA bystanders stimulates reflection, positively influencing the ability to cope with the emotional reactions and the cognitive perception of own performance and motivates improvement of CPR skills. Importantly, it increases confidence to provide CPR in the future. Implementation of telephone debriefing to bystanders at Emergency Medical Dispatch Centres is a low complexity and a low cost intervention though the logistic challenges have to be considered. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Damage of chromosoms under irradiation of human blood lymphocytes and development of bystander effect.

PubMed

Shemetun, O V

2016-12-01

the research the distribution of radiation induced damages among chromosomes and their bands in irra diated in vitro human blood lymphocytes and in unirradiated bystander cells.Material and methods of research: cultivation of human peripheral blood lymphocytes by semi micromethod D.A. Hungerford, modeling of radiation induced bystander effect in mixed cultures consisting of irradiated in vitro and non irradiated blood lymphocytes from persons of different gender, GTG staining of metaphase chromosomes and their cytogenetic analysis. Break points in chromosomes under the formation of aberrations were identified in exposed in vitro human peripheral blood lymphocytes in doses 0.25 Gy (95 breaks in 1248 cells) and 1.0 Gy (227 breaks in 726 cells) and in non irradiated bystander cells under their joint cultivation with irradiated in vitro human lymphocytes (51 breaks in 1137 cells at irradiation of adjacent populations of lymphocytes in dose 0.25 Gy and 75 breaks in 1321 cells at irradiation of adjacent population of lymphocytes in a dose 1.0 Gy). The distribution of injuries among the chromo somes and their bands was investigated. in radiation exposed in vitro human peripheral blood lymphocytes as well as in bystander cells the fre quency of damaged bands and number of breaks which localized in them exceeded the control value (p < 0.01). As under direct radiation exposure, as under formation of breaks due to induction of bystander effect, chromosomes were damaged according to their relative length. Location of bands with increasing number of breaks coincided with the «hot spots» of chromosome damage following irradiation and fragile sites. More sensitive to damage were G negative euchromatin chromosome bands, in which were localized 82 88 % breaks. Damageability of telomeric regions in the irradiated cells had no significant difference from the control, while in bystander cells was lower than control value (p < 0.05). O. V. Shemetun.

Proteomic overview and perspectives of the radiation-induced bystander effects.

PubMed

Chevalier, François; Hamdi, Dounia Houria; Saintigny, Yannick; Lefaix, Jean-Louis

2015-01-01

Radiation proteomics is a recent, promising and powerful tool to identify protein markers of direct and indirect consequences of ionizing radiation. The main challenges of modern radiobiology is to predict radio-sensitivity of patients and radio-resistance of tumor to be treated, but considerable evidences are now available regarding the significance of a bystander effect at low and high doses. This "radiation-induced bystander effect" (RIBE) is defined as the biological responses of non-irradiated cells that received signals from neighboring irradiated cells. Such intercellular signal is no more considered as a minor side-effect of radiotherapy in surrounding healthy tissue and its occurrence should be considered in adapting radiotherapy protocols, to limit the risk for radiation-induced secondary cancer. There is no consensus on a precise designation of RIBE, which involves a number of distinct signal-mediated effects within or outside the irradiated volume. Indeed, several cellular mechanisms were proposed, including the secretion of soluble factors by irradiated cells in the extracellular matrix, or the direct communication between irradiated and neighboring non-irradiated cells via gap junctions. This phenomenon is observed in a context of major local inflammation, linked with a global imbalance of oxidative metabolism which makes its analysis challenging using in vitro model systems. In this review article, the authors first define the radiation-induced bystander effect as a function of radiation type, in vitro analysis protocols, and cell type. In a second time, the authors present the current status of protein biomarkers and proteomic-based findings and discuss the capacities, limits and perspectives of such global approaches to explore these complex intercellular mechanisms. Copyright © 2014 Elsevier B.V. All rights reserved.

Role of ATM in bystander signaling between human monocytes and lung adenocarcinoma cells.

PubMed

Ghosh, Somnath; Ghosh, Anu; Krishna, Malini

2015-12-01

The response of a cell or tissue to ionizing radiation is mediated by direct damage to cellular components and indirect damage mediated by radiolysis of water. Radiation affects both irradiated cells and the surrounding cells and tissues. The radiation-induced bystander effect is defined by the presence of biological effects in cells that were not themselves in the field of irradiation. To establish the contribution of the bystander effect in the survival of the neighboring cells, lung carcinoma A549 cells were exposed to gamma-irradiation, 2Gy. The medium from the irradiated cells was transferred to non-irradiated A549 cells. Irradiated A549 cells as well as non-irradiated A549 cells cultured in the presence of medium from irradiated cells showed decrease in survival and increase in γ-H2AX and p-ATM foci, indicating a bystander effect. Bystander signaling was also observed between different cell types. Phorbol-12-myristate-13-acetate (PMA)-stimulated and gamma-irradiated U937 (human monocyte) cells induced a bystander response in non-irradiated A549 (lung carcinoma) cells as shown by decreased survival and increased γ-H2AX and p-ATM foci. Non-stimulated and/or irradiated U937 cells did not induce such effects in non-irradiated A549 cells. Since ATM protein was activated in irradiated cells as well as bystander cells, it was of interest to understand its role in bystander effect. Suppression of ATM with siRNA in A549 cells completely inhibited bystander effect in bystander A549 cells. On the other hand suppression of ATM with siRNA in PMA stimulated U937 cells caused only a partial inhibition of bystander effect in bystander A549 cells. These results indicate that apart from ATM, some additional factor may be involved in bystander effect between different cell types. Copyright © 2015 Elsevier B.V. All rights reserved.

Potential implications of the bystander effect on TCP and EUD when considering target volume dose heterogeneity.

PubMed

Balderson, Michael J; Kirkby, Charles

2015-01-01

In light of in vitro evidence suggesting that radiation-induced bystander effects may enhance non-local cell killing, there is potential for impact on radiotherapy treatment planning paradigms such as the goal of delivering a uniform dose throughout the clinical target volume (CTV). This work applies a bystander effect model to calculate equivalent uniform dose (EUD) and tumor control probability (TCP) for external beam prostate treatment and compares the results with a more common model where local response is dictated exclusively by local absorbed dose. The broad assumptions applied in the bystander effect model are intended to place an upper limit on the extent of the results in a clinical context. EUD and TCP of a prostate cancer target volume under conditions of increasing dose heterogeneity were calculated using two models: One incorporating bystander effects derived from previously published in vitro bystander data ( McMahon et al. 2012 , 2013a); and one using a common linear-quadratic (LQ) response that relies exclusively on local absorbed dose. Dose through the CTV was modelled as a normal distribution, where the degree of heterogeneity was then dictated by changing the standard deviation (SD). Also, a representative clinical dose distribution was examined as cold (low dose) sub-volumes were systematically introduced. The bystander model suggests a moderate degree of dose heterogeneity throughout a target volume will yield as good or better outcome compared to a uniform dose in terms of EUD and TCP. For a typical intermediate risk prostate prescription of 78 Gy over 39 fractions maxima in EUD and TCP as a function of increasing SD occurred at SD ∼ 5 Gy. The plots only dropped below the uniform dose values for SD ∼ 10 Gy, almost 13% of the prescribed dose. Small, but potentially significant differences in the outcome metrics between the models were identified in the clinically-derived dose distribution as cold sub-volumes were introduced. In terms of

Beta1-integrin and IL-1alpha expression as bystander effect of medium from irradiated cells: the pilot study.

PubMed

Osterreicher, Jan; Skopek, Jirí; Jahns, Juta; Hildebrandt, Guido; Psutka, Jan; Vilasová, Zdenka; Tanner, Judith Maria; Vogt, Jürgen; Butz, Tilman

2003-01-01

Bystander effects have been proposed as a third action pathway of ionising radiation besides direct and indirect effects. The purpose of the study was to investigate whether expression of interleukin-1alpha (IL-1alpha) and beta1-integrin is elevated in bystander cells as a marker for bystander effects in comparison with classical markers such as the clonogenic assay, apoptosis and the presence of micronuclei. The hybrid cell line E.A. hy.926 obtained by fusion of HUVEC cells with the epithelial cell line A 459 was irradiated with 0-5 Gy. Bystander effects were established via medium transfer at 45 min and 4 h after irradiation from irradiated to nonirradiated cell populations. In order to exclude effects of the irradiated medium itself, irradiated medium only was also used for transfer to nonirradiated cells. Then, cells were fixed at 1, 2, 6, and 24 h after irradiation or medium transport and IL-1alpha and beta1-integrin were detected and evaluated. A higher number of beta1-integrin-positive cells was observed in both irradiated and bystander cell populations than in the control group at 1 and 24 h after irradiation with 1 Gy or medium transfer. Significantly higher numbers of IL-1alpha-positive cells were found at 1, 2, and 6 h after irradiation with 1 Gy or medium transfer as well as at 2 and 6 h after irradiation with 5 Gy or medium transfer. Clonogenic survival decreased dependently on the dose in irradiated cells but did not show any significant difference between the bystander cell populations and sham-irradiated cells. The irradiated medium itself did not have any effect. It is concluded that beta1-integrin and IL-1alpha expression may serve as more sensitive markers of post-irradiation responses in bystander cell populations than the classical radiobiological markers. Moreover, overexpression of beta1-integrin and IL-1alpha may induce increased susceptibility to inflammation of bystander cells.

Improved Anticancer Photothermal Therapy Using the Bystander Effect Enhanced by Antiarrhythmic Peptide Conjugated Dopamine-Modified Reduced Graphene Oxide Nanocomposite.

PubMed

Yu, Jiantao; Lin, Yu-Hsin; Yang, Lingyan; Huang, Chih-Ching; Chen, Liliang; Wang, Wen-Cheng; Chen, Guan-Wen; Yan, Junyan; Sawettanun, Saranta; Lin, Chia-Hua

2017-01-01

Despite tremendous efforts toward developing novel near-infrared (NIR)-absorbing nanomaterials, improvement in therapeutic efficiency remains a formidable challenge in photothermal cancer therapy. This study aims to synthesize a specific peptide conjugated polydopamine-modified reduced graphene oxide (pDA/rGO) nanocomposite that promotes the bystander effect to facilitate cancer treatment using NIR-activated photothermal therapy. To prepare a nanoplatform capable of promoting the bystander effect in cancer cells, we immobilized antiarrhythmic peptide 10 (AAP10) on the surface of dopamine-modified rGO (AAP10-pDA/rGO). Our AAP10-pDA/rGO could promote the bystander effect by increasing the expression of connexin 43 protein in MCF-7 breast-cancer cells. Because of its tremendous ability to absorb NIR absorption, AAP10-pDA/rGO offers a high photothermal effect under NIR irradiation. This leads to a massive death of MCF-7 cells via the bystander effect. Using tumor-bearing mice as the model, it is found that NIR radiation effectively ablates breast tumor in the presence of AAP10-pDA/rGO and inhibits tumor growth by ≈100%. Therefore, this research integrates the bystander and photothermal effects into a single nanoplatform in order to facilitate an efficient photothermal therapy. Furthermore, our AAP10-pDA/rGO, which exhibits both hyperthermia and the bystander effect, can prevent breast-cancer recurrence and, therefore, has great potential for future clinical and research applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bystanders Are the Key to Stopping Bullying

ERIC Educational Resources Information Center

Padgett, Sharon; Notar, Charles E.

2013-01-01

Bullying is the dominance over another. Bullying occurs when there is an audience. Peer bystanders provide an audience 85% of instances of bullying. If you remove the audience bullying should stop. The article is a review of literature (2002-2013) on the role of bystanders; importance of bystanders; why bystanders behave as they do; resources to…

Does Non-Targeted Community CPR Training Increase Bystander CPR Frequency?

PubMed

Uber, Amy; Sadler, Richard C; Chassee, Todd; Reynolds, Joshua C

2018-05-01

Only 37% of out-of-hospital cardiac arrests (OHCA) receive bystander Cardiopulmonary resuscitation (CPR) in Kent County, MI. In May 2014, prehospital providers offered one-time, point-of-contact compression-only CPR training to 2,253 passersby at 7 public locations in Grand Rapids, Michigan. To assess the impact of this intervention, we compared bystander CPR frequency and clinical outcomes in regions surrounding training sites before and after the intervention, adjusting for prehospital covariates. We aimed to assess the effect of this broad, non-targeted intervention on bystander CPR frequency, type of CPR utilized, and clinical outcomes. We also tested for differences in geospatial variation of bystander CPR and clinical outcomes clustered around training sites. Retrospective, observational, before-after study of adult, EMS-treated OHCA in Kent County from January 1, 2010 to December 31, 2015. We generated a 5-kilometer radius surrounding each training site to estimate any geospatial influence that training sites might have on bystander CPR frequency in nearby OHCA cases. Chi-squared, Fisher's exact, and t-tests assessed differences in subject features. Difference-in-differences analysis with generalized estimating equation (GEE) modeling assessed bystander CPR frequency, adjusting for training site, covariates (age, sex, witnessed, shockable rhythm, public location), and clustering around training sites. Similar modeling tested for changes in bystander CPR type, return of spontaneous circulation (ROSC), survival to hospital discharge, and cerebral performance category (CPC) of 1-2 at hospital discharge. We included 899 cases before and 587 cases post-intervention. Overall, we observed no increase in the frequency of bystander CPR or favorable clinical outcomes. We did observe an increase in compression-only CPR, but this was paradoxically restricted to OHCA cases falling outside radii around training sites. In adjusted modeling, the bystander CPR training

Exposures involving perturbations of the EM field have non-linear effects on radiation response and can alter the expression of radiation induced bystander effects

NASA Astrophysics Data System (ADS)

Mothersill, Carmel; Seymour, Colin

2012-07-01

Our recent data suggest there is a physical component to the bystander signal induced by radiation exposure and that alternative medicine techniques such as Reiki and acupuncture or exposures to weak EM fields alter the response of cells to direct irradiation and either altered bystander signal production or altered the response of cells receiving bystander signals. Our proposed mechanism to explain these findings is that perturbation of electromagnetic (EM) fields is central to the induction of low radiation dose responses especially non-targeted bystander effects. In this presentation we review the alternative medicine data and other data sets from our laboratory which test our hypothesis that perturbation of bio-fields will modulate radiation response in the low dose region. The other data sets include exposure to MRI, shielding using lead and or Faraday cages, the use of physical barriers to bystander signal transmission and the use of membrane channel blockers. The data taken together strongly suggest that EM field perturbation can modulate low dose response and that in fact the EM field rather than the targeted deposition of ionizing energy in the DNA may be the key determinant of dose response in a cell or organism The results also lead us to suspect that at least when chemical transmission is blocked, bystander signals can be transmitted by other means. Our recent experiments suggest light signals and volatiles are not likely. We conclude that alternative medicine and other techniques involving electromagnetic perturbations can modify the response of cells to low doses of ionizing radiation and can induce bystander effects similar to those seen in medium transfer experiments. In addition to the obvious implications for mechanistic studies of low dose effects, this could perhaps provide a novel target to exploit in space radiation protection and in optimizing therapeutic gain during radiotherapy.

Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish

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

Smith, Richard W., E-mail: rich.wilson.smith@gmail.com; Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario; Seymour, Colin B.

The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48 h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyedmore » eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. - Highlights: • We evaluated the transgenerational effect of early life irradiation in rainbow trout. • Trout irradiated as eggs, yolk sac larvae or first feeders were crossed. • A transgenerational effect was evident in two generations after irradiation. • F1 and F2 generation fish induced a bystander effect in non-irradiated fish. • The precise effects were tissue specific and dependent

Are nonparticipants in prosocial behavior merely innocent bystanders?

PubMed

Anker, Ashley E; Feeley, Thomas Hugh

2011-01-01

Latané and Darley's (1970) bystander intervention theory was used to model individuals' participation in two prosocial behaviors (organ donation, green living). It is argued that nonparticipants in prosocial helping are innocent bystanders who likely fail to notice the need, do not interpret the cause as an emergency, do not accept responsibility for the need to help, and have little knowledge on how to help. Data in study 1 (n = 494) indicate support for the proposed innocent bystander path model (notice event → interpret event as emergency → accept responsibility → knowledge of how to help) in organ donation. Study 2 (n = 519) replicated the model in the context of green living and additionally found a direct path from noticing the event to knowledge of how to help. Implications of framing nonparticipation in prosocial behaviors as innocent bystander effects are discussed in context of campaign communication.

Reactive oxygen species formation and bystander effects in gradient irradiation on human breast cancer cells.

PubMed

Zhang, Dongqing; Zhou, Tingyang; He, Feng; Rong, Yi; Lee, Shin Hee; Wu, Shiyong; Zuo, Li

2016-07-05

Ionizing radiation (IR) in cancer radiotherapy can induce damage to neighboring cells via non-targeted effects by irradiated cells. These so-called bystander effects remain an area of interest as it may provide enhanced efficacy in killing carcinomas with minimal radiation. It is well known that reactive oxygen species (ROS) are ubiquitous among most biological activities. However, the role of ROS in bystander effects has not been thoroughly elucidated. We hypothesized that gradient irradiation (GI) has enhanced therapeutic effects via the ROS-mediated bystander pathways as compared to uniform irradiation (UI). We evaluated ROS generation, viability, and apoptosis in breast cancer cells (MCF-7) exposed to UI (5 Gy) or GI (8-2 Gy) in radiation fields at 2, 24 and 48 h after IR. We found that extracellular ROS release induced by GI was higher than that by UI at both 24 h (p < 0.001) and 48 h (p < 0.001). More apoptosis and less viability were observed in GI when compared to UI at either 24 h or 48 h after irradiation. The mean effective doses (ED) of GI were ~130% (24 h) and ~48% (48 h) higher than that of UI, respectively. Our results suggest that GI is superior to UI regarding redox mechanisms, ED, and toxic dosage to surrounding tissues.

The differential role of human macrophage in triggering secondary bystander effects after either gamma-ray or carbon beam irradiation

PubMed Central

Dong, Chen; He, Mingyuan; Tu, Wenzhi; Konishi, Teruaki; Liu, Weili; Xie, Yuexia; Dang, Bingrong; Li, Wenjian; Uchihori, Yukio; Hei, Tom K.; Shao, Chunlin

2015-01-01

The abscopal effect could be an underlying factor in evaluating prognosis of radiotherapy. This study established an in vitro system to examine whether tumor-generated bystander signals could be transmitted by macrophages to further trigger secondary cellular responses after different irradiations, where human lung cancer NCI-H446 cells were irradiated with either γ-rays or carbon ions and co-cultured with human macrophage U937 cells, then these U937 cells were used as a bystander signal transmitter and co-cultured with human bronchial epithelial cells BEAS-2B. Results showed that U937 cells were only activated by γ-irradiated NCI-H446 cells so that the secondary injuries in BEAS-2B cells under carbon ion irradiation were weaker than γ-rays. Both TNF-α and IL-1α were involved in γ-irradiation induced secondary bystander effect but only TNF-α contributed to the carbon ion induced response. Further assay disclosed that IL-1α but not TNF-α was largely responsible for the activation of macrophages and the formation of micronucleus in BEAS-2B cells. These data suggest that macrophages could transfer secondary bystander signals and play a key role in the secondary bystander effect of photon irradiation while carbon ion irradiation has conspicuous advantage due to its reduced secondary injury. PMID:25896631

The differential role of human macrophage in triggering secondary bystander effects after either gamma-ray or carbon beam irradiation.

PubMed

Dong, Chen; He, Mingyuan; Tu, Wenzhi; Konishi, Teruaki; Liu, Weili; Xie, Yuexia; Dang, Bingrong; Li, Wenjian; Uchihori, Yukio; Hei, Tom K; Shao, Chunlin

2015-07-10

The abscopal effect could be an underlying factor in evaluating prognosis of radiotherapy. This study established an in vitro system to examine whether tumor-generated bystander signals could be transmitted by macrophages to further trigger secondary cellular responses after different irradiations, where human lung cancer NCI-H446 cells were irradiated with either γ-rays or carbon ions and co-cultured with human macrophage U937 cells, then these U937 cells were used as a bystander signal transmitter and co-cultured with human bronchial epithelial cells BEAS-2B. Results showed that U937 cells were only activated by γ-irradiated NCI-H446 cells so that the secondary injuries in BEAS-2B cells under carbon ion irradiation were weaker than γ-rays. Both TNF-α and IL-1α were involved in the γ-irradiation induced secondary bystander effect but only TNF-α contributed to the carbon ion induced response. Further assay disclosed that IL-1α but not TNF-α was largely responsible for the activation of macrophages and the formation of micronucleus in BEAS-2B cells. These data suggest that macrophages could transfer secondary bystander signals and play a key role in the secondary bystander effect of photon irradiation, while carbon ion irradiation has conspicuous advantage due to its reduced secondary injury. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

TakeCARE, a Video to Promote Bystander Behavior on College Campuses: Replication and Extension.

PubMed

Jouriles, Ernest N; Sargent, Kelli S; Salis, Katie Lee; Caiozzo, Christina; Rosenfield, David; Cascardi, Michele; Grych, John H; O'Leary, K Daniel; McDonald, Renee

2017-08-01

Previous research has demonstrated that college students who view TakeCARE, a video bystander program designed to encourage students to take action to prevent sexual and relationship violence (i.e., bystander behavior), display more bystander behavior relative to students who view a control video. The current study aimed to replicate and extend these findings by testing two different methods of administering TakeCARE and examining moderators of TakeCARE's effects on bystander behavior. Students at four universities ( n = 557) were randomly assigned to one of three conditions: (a) view TakeCARE in a monitored computer lab, (b) view TakeCARE at their own convenience after receiving an email link to the video, or (c) view a video about study skills (control group). Participants completed measures of bystander behavior at baseline and at a 1-month follow-up. Participants in both TakeCARE conditions reported more bystander behavior at follow-up assessments, compared with participants in the control condition. The beneficial effect of TakeCARE did not differ significantly across administration methods. However, the effects of TakeCARE on bystander behavior were moderated by students' perceptions of campus responsiveness to sexual violence, with more potent effects when students perceived their institution as responsive to reports of sexual violence.

X-ray-induced bystander responses reduce spontaneous mutations in V79 cells

PubMed Central

Maeda, Munetoshi; Kobayashi, Katsumi; Matsumoto, Hideki; Usami, Noriko; Tomita, Masanori

2013-01-01

The potential for carcinogenic risks is increased by radiation-induced bystander responses; these responses are the biological effects in unirradiated cells that receive signals from the neighboring irradiated cells. Bystander responses have attracted attention in modern radiobiology because they are characterized by non-linear responses to low-dose radiation. We used a synchrotron X-ray microbeam irradiation system developed at the Photon Factory, High Energy Accelerator Research Organization, KEK, and showed that nitric oxide (NO)-mediated bystander cell death increased biphasically in a dose-dependent manner. Here, we irradiated five cell nuclei using 10 × 10 µm2 5.35 keV X-ray beams and then measured the mutation frequency at the hypoxanthine-guanosine phosphoribosyl transferase (HPRT) locus in bystander cells. The mutation frequency with the null radiation dose was 2.6 × 10–5 (background level), and the frequency decreased to 5.3 × 10–6 with a dose of approximately 1 Gy (absorbed dose in the nucleus of irradiated cells). At high doses, the mutation frequency returned to the background level. A similar biphasic dose-response effect was observed for bystander cell death. Furthermore, we found that incubation with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), a specific scavenger of NO, suppressed not only the biphasic increase in bystander cell death but also the biphasic reduction in mutation frequency of bystander cells. These results indicate that the increase in bystander cell death involves mechanisms that suppress mutagenesis. This study has thus shown that radiation-induced bystander responses could affect processes that protect the cell against naturally occurring alterations such as mutations. PMID:23660275

Rethinking the bystander role in school violence prevention.

PubMed

Stueve, Ann; Dash, Kimberly; O'Donnell, Lydia; Tehranifar, Parisa; Wilson-Simmons, Renée; Slaby, Ronald G; Link, Bruce G

2006-01-01

Public concerns about school shootings and safety draw attention to the role bystanders can play in preventing school violence. Although school violence prevention plans are often required, there is little guidance about whether these should address the roles of bystanders and what actions bystanders should take in different circumstances, from more common instances of bullying and fighting to rare, but potentially lethal, threats and use of weapons. Literature pertaining to bystanders is reviewed and applied to the school setting. The definition of bystander is expanded, including parents, teachers, and other school staff as well as youths and those who have information about potential violence as well as those who witness its occurrence. Barriers preventing bystanders from taking positive actions are discussed. The authors call on health promotion researchers and practitioners to work with school communities to identify norms, attitudes, and outcome expectancies that shape bystander behaviors to inform prevention efforts.

Bystander Programs: Accommodating or Derailing Sexism?

PubMed Central

Reid, Adam; Dundes, Lauren

2017-01-01

Bystander programs implemented to meet federal requirements to reduce sexual assaults on college campuses in the United States must include primary prevention. Survey data (n = 280) and interview data (n = 20) presented in this paper explore students’ hypothetical and actual willingness to intervene as bystanders. Although most students surveyed (57%) claim they would be very likely to intervene, fewer than half would be very suspicious of someone leading away an intoxicated individual at a party (45% of women and 28% of men: p < 0.01). Interview data reveal how students perceive risk factors at college parties and what types of bystander measures they attempt, including “distractions”, a nonconfrontational tactic in which bystanders avoid more direct but socially risky interventions. Subsumed in many current bystander programs is an invisible element of valorizing harmony. Condoning bystanders’ unwillingness to directly confront seemingly predatory individuals could make change seem out of reach and could also embolden offenders whose behavior is observed and only temporarily thwarted. PMID:29299348

Propagation Distance of the α-Particle-Induced Bystander Effect: The Role of Nuclear Traversal and Gap Junction Communication

PubMed Central

Gaillard, Sylvain; Pusset, David; de Toledo, Sonia M.; Fromm, Michel; Azzam, Edouard I.

2009-01-01

When cell populations are exposed to low-dose α-particle radiation, a significant fraction of the cells will not be traversed by a radiation track. However, stressful effects occur in both irradiated and bystander cells in the population. Characterizing these effects, and investigating their underlying mechanism(s), is critical to understanding human health risks associated with exposure to α particles. To this end, confluent normal human fibroblast cultures were grown on polyethylene terephthalate foil grafted to an ultrathin solid-state nuclear track detector and exposed under non-perturbing conditions to low-fluence α particles from a broadbeam irradiator. Irradiated and affected bystander cells were localized with micrometer precision. The stress-responsive protein p21Waf1 (also known as CDKN1A) was induced in bystander cells within a 100-µm radius from an irradiated cell. The mean propagation distance ranged from 20 to 40 µm around the intranuclear α-particle impact point, which corresponds to a set of ∼30 cells. Nuclear traversal, induced DNA damage, and gap junction communication were critical contributors to propagation of this stressful effect The strategy described here may be ideal to investigate the size of radiation-affected target and the relative contribution of different cellular organelles to bystander effects induced by energetic particles, which is relevant to radioprotection and cancer radiotherapy. PMID:19580486

Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish.

PubMed

Smith, Richard W; Seymour, Colin B; Moccia, Richard D; Mothersill, Carmel E

2016-02-01

The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. Copyright © 2015 Elsevier Inc. All rights reserved.

Not All Behind Closed Doors: Examining Bystander Involvement in Intimate Partner Violence.

PubMed

Taylor, Elizabeth; Banyard, Victoria; Grych, John; Hamby, Sherry

2016-10-01

It is often said that intimate partner violence (IPV) happens "behind closed doors"; however, research on IPV and other crimes suggests that witnesses are sometimes present. This suggests that bystanders may be in a position to help victims or potential victims of violence. Bystander behavior has been studied primarily in school settings, and consequently, little is known about how often it occurs or what its effects may be in the broader community. This study examined IPV incidents in a rural sample to assess the presence and potential impact of bystanders on victim-reported outcomes. One thousand nine hundred seventy-seven adult participants completed a questionnaire that asked about five violent behaviors (my partner threatened to hurt me; pushed, grabbed, or shook me; hit me; beat me up; sexually assaulted me), bystander characteristics, and victim outcomes (fear; injury; disruption of daily routines; mental health). Adult or teen bystanders were present for each IPV approximately one third of the time, except in the case of sexual assault (14.3%). When a bystander was present, victims reported higher rates of injury, greater disruption in their routines, and poorer mental health. When a bystander's safety was threatened, victims reported more physical injury and more routine disruption. A considerable number of IPV incidents do not happen behind closed doors, and the presence of a bystander was associated with worse outcomes for victims. Prevention efforts for adult IPV may need to take a more cautious or nuanced approach to encouraging bystander action, especially when confronted with more severe incidents. Bystander safety should be a priority for violence prevention.

Do dispatcher instructions facilitate bystander-initiated cardiopulmonary resuscitation and improve outcomes in patients with out-of-hospital cardiac arrest? A comparison of family and non-family bystanders.

PubMed

Fujie, Keiko; Nakata, Yoshio; Yasuda, Susumu; Mizutani, Taro; Hashimoto, Koichi

2014-03-01

Bystander-initiated cardiopulmonary resuscitation (CPR) has been reported to increase the possibility of survival in patients with out-of-hospital cardiopulmonary arrest (OHCA). We evaluated the effects of CPR instructions by emergency medical dispatchers on the frequency of bystander CPR and outcomes, and whether these effects differed between family and non-family bystanders. We conducted a retrospective cohort study, using Utstein-style records of OHCA taken in a rural area of Japan between January 2004 and December 2009. Of the 559 patients with non-traumatic OHCA witnessed by laypeople, 231 (41.3%) were given bystander CPR. More OHCA patients received resuscitation when the OHCA was witnessed by non-family bystanders than when it was witnessed by family members (61.4% vs. 34.2%). The patients with non-family-witnessed OHCA were more likely to be given conventional CPR (chest compression plus rescue breathing) or defibrillation with an AED than were those with family-witnessed OHCA. Dispatcher instructions significantly increased the provision of bystander CPR regardless of who the witnesses were. Neurologically favorable survival was increased by CPR in non-family-witnessed, but not in family-witnessed, OHCA patients. No difference in survival rate was observed between the cases provided with dispatcher instructions and those not provided with the instructions. Dispatcher instructions increased the frequency of bystander CPR, but did not improve the rate of neurologically favorable survival in patients with witnessed OHCA. Efforts to enhance the frequency and quality of resuscitation, especially by family members, are required for dispatcher-assisted CPR. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

3D-modelling of radon-induced cellular radiobiological effects in bronchial airway bifurcations: direct versus bystander effects.

PubMed

Szőke, István; Farkas, Arpád; Balásházy, Imre; Hofmann, Werner; Madas, Balázs G; Szőke, Réka

2012-06-01

The primary objective of this paper was to investigate the distribution of radiation doses and the related biological responses in cells of a central airway bifurcation of the human lung of a hypothetical worker of the New Mexico uranium mines during approximately 12 hours of exposure to short-lived radon progenies. State-of-the-art computational modelling techniques were applied to simulate the relevant biophysical and biological processes in a central human airway bifurcation. The non-uniform deposition pattern of inhaled radon daughters caused a non-uniform distribution of energy deposition among cells, and of related cell inactivation and cell transformation probabilities. When damage propagation via bystander signalling was assessed, it produced more cell killing and cell transformation events than did direct effects. If bystander signalling was considered, variations of the average probabilities of cell killing and cell transformation were supra-linear over time. Our results are very sensitive to the radiobiological parameters, derived from in vitro experiments (e.g., range of bystander signalling), applied in this work and suggest that these parameters may not be directly applicable to realistic three-dimensional (3D) epithelium models.

Stochastic models of the bystander effect and of transmissible genomic instability: implications for mechanisms and low dose risks

NASA Astrophysics Data System (ADS)

Little, M. P.

Bystander effects following exposure to α -particles have been observed in C3H 10T cells and in other experimental systems, and imply that linearly extrapolating low dose risks from high-dose data might materially underestimate risk. In many experimental systems there is evidence of saturation of dose response that would be expected from the bystander effect. The ratio of lung cancer risk among persons exposed to low and high doses of radon daughters is 2.4 -- 4.0, with an upper 95% confidence limit of about 14. Assuming the bystander effect observed in the C3H 10T data applies to human lung cells in vivo, the epidemiological data imply that the number of neighbouring cells that can contribute to the bystander effect is between 0 and 1, with an upper 95% confidence limit of about 7. As a consequence, the bystander effect observed in the C3H 10T system probably does not play a large part in the process of radon-induced lung carcinogenesis in humans. Other experimental data relating to the bystander effect after α -particle exposure are surveyed; some of these data are more compatible with the epidemiological data. Three models of genomic instability recently developed by Little and Wright (Math. Biosci. 2003;183:111-34), with two, three and five stages, are compared with the four-stage model proposed by Luebeck and Moolgavkar (PNAS 2002;99:15095-100) and the two-stage model of Nowak et al. (PNAS 2002;99:16226-31). All models are fitted to SEER colon cancer data. Although the five-stage model of Little and Wright (2003) provides the best fit, it is not much superior to that of the model of Nowak et al. (2002) or the two- and three-stage models of Little and Wright (2003). The fit of the model of Luebeck and Moolgavkar (2002) is somewhat worse than these three, particularly for females under the age of 40. Comparison of the predictions of the two-stage models of Little and Wright (2003) and Nowak (2002) with patterns of excess risk in the Japanese atomic bomb

Predicting Improvement After a Bystander Program for the Prevention of Sexual and Dating Violence.

PubMed

Hines, Denise A; Palm Reed, Kathleen M

2015-07-01

Although evidence suggests that bystander prevention programs are promising interventions for decreasing sexual violence and dating violence on college campuses, there have been no studies to date evaluating moderators of bystander program effectiveness. The current study evaluates whether different demographic characteristics, attitudes, knowledge, and behaviors at pretest predict change over a 6-month follow-up for students who participated in a bystander prevention program. Participants in the three assessments (pretest, posttest, 6-month follow-up) included 296 college students who were mandated to attend a bystander program during their first year orientation. Analyses showed that with few exceptions, the bystander program worked best for students who were most at risk given their pretest demographics and levels of attitudes condoning dating violence and sexual violence, bystander efficacy, and bystander behaviors. Results are discussed in terms of suggestions for future research. © 2014 Society for Public Health Education.

Spatially Fractionated Radiation Induces Cytotoxicity and Changes in Gene Expression in Bystander and Radiation Adjacent Murine Carcinoma Cells

PubMed Central

Asur, Rajalakshmi S.; Sharma, Sunil; Chang, Ching-Wei; Penagaricano, Jose; Kommuru, Indira M.; Moros, Eduardo G.; Corry, Peter M.; Griffin, Robert J.

2012-01-01

Radiation-induced bystander effects have been extensively studied at low doses, since evidence of bystander induced cell killing and other effects on unirradiated cells were found to be predominant at doses up to 0.5 Gy. Therefore, few studies have examined bystander effects induced by exposure to higher doses of radiation, such as spatially fractionated radiation (GRID) treatment. In the present study, we evaluate the ability of GRID treatment to induce changes in GRID adjacent (bystander) regions, in two different murine carcinoma cell lines following exposure to a single irradiation dose of 10 Gy. Murine SCK mammary carcinoma cells and SCCVII squamous carcinoma cells were irradiated using a brass collimator to create a GRID pattern of nine circular fields 12 mm in diameter with a center-to-center distance of 18 mm. Similar to the typical clinical implementation of GRID, this is approximately a 50:50 ratio of direct and bystander exposure. We also performed experiments by irradiating separate cultures and transferring the medium to unirradiated bystander cultures. Clonogenic survival was evaluated in both cell lines to determine the occurrence of radiation-induced bystander effects. For the purpose of our study, we have defined bystander cells as GRID adjacent cells that received approximately 1 Gy scatter dose or unirradiated cells receiving conditioned medium from irradiated cells. We observed significant bystander killing of cells adjacent to the GRID irradiated regions compared to sham treated controls. We also observed bystander killing of SCK and SCCVII cells cultured in conditioned medium obtained from cells irradiated with 10 Gy. Therefore, our results confirm the occurrence of bystander effects following exposure to a high-dose of radiation and suggest that cell-to-cell contact is not required for these effects. In addition, the gene expression profile for DNA damage and cellular stress response signaling in SCCVII cells after GRID exposure was studied

Radiation-induced genomic instability and bystander effects: related inflammatory-type responses to radiation-induced stress and injury? A review.

PubMed

Lorimore, S A; Wright, E G

2003-01-01

To review studies of radiation responses in the haemopoietic system in the context of radiation-induced genomic instability, bystander effects and inflammatory-type processes. There is considerable evidence that cells that themselves are not exposed to ionizing radiation but are the progeny of cells irradiated many cell divisions previously may express a high frequency of gene mutations, chromosomal aberrations and cell death. These effects are collectively known as radiation-induced genomic instability. A second untargeted effect results in non-irradiated cells exhibiting responses typically associated with direct radiation exposure but occurs as a consequence of contact with irradiated cells or by receiving soluble signals from irradiated cells. These effects are collectively known as radiation-induced bystander effects. Reported effects include increases or decreases in damage-inducible and stress-related proteins; increases or decreases in reactive oxygen species, cell death or cell proliferation, and induction of mutations and chromosome aberrations. This array of responses is reminiscent of effects mediated by cytokines and other similar regulatory factors that may involve, but do not necessarily require, gap junction-mediated transfer, have multiple inducers and a variety of context-dependent consequences in different cell systems. That chromosomal instability in haemopoietic cells can be induced by an indirect bystander-type mechanism both in vitro and in vivo provides a potential link between these two untargeted effects and there are radiation responses in vivo consistent with the microenvironment contributing secondary cell damage as a consequence of an inflammatory-type response to radiation-induced injury. Intercellular signalling, production of cytokines and free radicals are features of inflammatory responses that have the potential for both bystander-mediated and persisting damage as well as for conferring a predisposition to malignancy. The

Theoretical models and simulation codes to investigate bystander effects and cellular communication at low doses

NASA Astrophysics Data System (ADS)

Ballarini, F.; Alloni, D.; Facoetti, A.; Mairani, A.; Nano, R.; Ottolenghi, A.

Astronauts in space are continuously exposed to low doses of ionizing radiation from Galactic Cosmic Rays During the last ten years the effects of low radiation doses have been widely re-discussed following a large number of observations on the so-called non targeted effects in particular bystander effects The latter consist of induction of cytogenetic damage in cells not directly traversed by radiation most likely as a response to molecular messengers released by directly irradiated cells Bystander effects which are observed both for lethal endpoints e g clonogenic inactivation and apoptosis and for non-lethal ones e g mutations and neoplastic transformation tend to show non-linear dose responses This might have significant consequences in terms of low-dose risk which is generally calculated on the basis of the Linear No Threshold hypothesis Although the mechanisms underlying bystander effects are still largely unknown it is now clear that two types of cellular communication i e via gap junctions and or release of molecular messengers into the extracellular environment play a fundamental role Theoretical models and simulation codes can be of help in elucidating such mechanisms In the present paper we will review different available modelling approaches including one that is being developed at the University of Pavia The focus will be on the different assumptions adopted by the various authors and on the implications of such assumptions in terms of non-targeted radiobiological damage and more generally low-dose

Selective replication of oncolytic virus M1 results in a bystander killing effect that is potentiated by Smac mimetics.

PubMed

Cai, Jing; Lin, Yuan; Zhang, Haipeng; Liang, Jiankai; Tan, Yaqian; Cavenee, Webster K; Yan, Guangmei

2017-06-27

Oncolytic virotherapy is a treatment modality that uses native or genetically modified viruses that selectively replicate in and kill tumor cells. Viruses represent a type of pathogen-associated molecular pattern and thereby induce the up-regulation of dozens of cytokines via activating the host innate immune system. Second mitochondria-derived activator of caspases (Smac) mimetic compounds (SMCs), which antagonize the function of inhibitor of apoptosis proteins (IAPs) and induce apoptosis, sensitize tumor cells to multiple cytokines. Therefore, we sought to determine whether SMCs sensitize tumor cells to cytokines induced by the oncolytic M1 virus, thus enhancing a bystander killing effect. Here, we report that SMCs potentiate the oncolytic effect of M1 in vitro, in vivo, and ex vivo. This strengthened oncolytic efficacy resulted from the enhanced bystander killing effect caused by the M1 virus via cytokine induction. Through a microarray analysis and subsequent validation using recombinant cytokines, we identified IL-8, IL-1A, and TRAIL as the key cytokines in the bystander killing effect. Furthermore, SMCs increased the replication of M1, and the accumulation of virus protein induced irreversible endoplasmic reticulum stress- and c-Jun N-terminal kinase-mediated apoptosis. Nevertheless, the combined treatment with M1 and SMCs had little effect on normal and human primary cells. Because SMCs selectively and significantly enhance the bystander killing effect and the replication of oncolytic virus M1 specifically in cancer cells, this combined treatment may represent a promising therapeutic strategy.

Is there a common mechanism underlying genomic instability, bystander effects and other nontargeted effects of exposure to ionizing radiation?

NASA Technical Reports Server (NTRS)

Morgan, William F.

2003-01-01

A number of nontargeted and delayed effects associated with radiation exposure have now been described. These include radiation-induced genomic instability, death-inducing and bystander effects, clastogenic factors and transgenerational effects. It is unlikely that these nontargeted effects are directly induced by cellular irradiation. Instead, it is proposed that some as yet to be identified secreted factor can be produced by irradiated cells that can stimulate effects in nonirradiated cells (death-inducing and bystander effects, clastogenic factors) and perpetuate genomic instability in the clonally expanded progeny of an irradiated cell. The proposed factor must be soluble and capable of being transported between cells by cell-to-cell gap junction communication channels. Furthermore, it must have the potential to stimulate cellular cytokines and/or reactive oxygen species. While it is difficult to imagine a role for such a secreted factor in contributing to transgenerational effects, the other nontargeted effects of radiation may all share a common mechanism.

Do Sexual Assault Bystander Interventions Change Men's Intentions? Applying the Theory of Normative Social Behavior to Predicting Bystander Outcomes.

PubMed

Mabry, Amanda; Turner, Monique Mitchell

2016-01-01

The high prevalence of sexual assault on college campuses has led to the implementation of health communication programs to prevent sexual assault. A few novel programs focus on primary prevention by targeting social norms related to gender and masculinity among men through bystander intervention. Guided by the theory of normative social behavior, this study sought to examine the relative effect of campaigns communicating positive versus negative injunctive norms and the interaction between exposure to such campaign messages and perceived descriptive norms and relevant cognitive moderators (e.g., outcome expectations, injunctive norms, group identity, ego involvement) among men. A 2 (high/low descriptive norms) × 2 (high/low moderator) × 3 (public service announcement) independent groups quasi-experimental design (N = 332) was used. Results indicated that messages communicating positive injunctive norms were most effective among men who were least likely to engage in bystander intervention. Furthermore, descriptive norms played a significant role in behavioral intentions, such that those with stronger norms were more likely to report intentions to engage in bystander behaviors in the future. Similarly, the moderators of aspiration, injunctive norms, social approval, and ego involvement had a significant positive effect on behavioral intentions. These findings have important implications for future message design strategy and audience segmentation.

Mechanism of bystander-blaming: defensive attribution, counterfactual thinking, and gender.

PubMed

Levy, Inna; Ben-David, Sarah

2015-01-01

Contemporary victimology recognizes that an understanding of the mechanism of blaming requires a comprehensive approach that includes the victim, the offender, and the bystander. However, most of the existing research on blaming focuses on the victim and the offender, ignoring the issue of bystander-blaming. This study highlights the bystander and investigates bystander-blaming by exploring some theoretical explanations, including counterfactual thinking, defensive attribution, and gender differences. The study included 363 young male and female participants, who read vignettes describing the behavior of the victim and the bystander in a rape scenario and answered questions regarding bystander-blaming. The results show that both counterfactual thinking and defensive attribution play a role in bystander-blaming. This article addresses the theoretical and practical implications of these findings. © The Author(s) 2013.

Tanshinone IIA Increases the Bystander Effect of Herpes Simplex Virus Thymidine Kinase/Ganciclovir Gene Therapy via Enhanced Gap Junctional Intercellular Communication

PubMed Central

Liu, Xijuan; Wu, Yingya; Du, Biaoyan; Li, Jiefen; Zhou, Jing; Li, Jingjing; Tan, Yuhui

2013-01-01

The bystander effect is an intriguing phenomenon by which adjacent cells become sensitized to drug treatment during gene therapy with herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV). This effect is reported to be mediated by gap junctional intercellular communication (GJIC), and therefore, we postulated that upregulation of genes that facilitate GJIC may enhance the HSV-tk/GCV bystander effect. Previous findings have shown Tanshinone IIA (Tan IIA), a chemical substance derived from a Chinese medicine herb, promotes the upregulation of the connexins Cx26 and Cx43 in B16 cells. Because gap junctions are formed by connexins, we hypothesized that Tan IIA might increase GJIC. Our results show that Tan IIA increased GJIC in B16 melanoma cells, leading to more efficient GCV-induced bystander killing in cells stably expressing HSV-tk. Additionally, in vivo experiments demonstrated that tumors in mice with 10% HSV-tk positive B16 cells and 90% wild-type B16 cells became smaller following treatment with the combination of GCV and Tan IIA as compared to GCV or Tan IIA alone. These data demonstrate that Tan IIA can augment the bystander effect of HSV-tk/GCV system through increased gap junction coupling, which adds strength to the promising strategy that develops connexins inducer to potentiate the effects of suicide gene therapy. PMID:23861780

Bystander motivation in bullying incidents: to intervene or not to intervene?

PubMed

Thornberg, Robert; Tenenbaum, Laura; Varjas, Kris; Meyers, Joel; Jungert, Tomas; Vanegas, Gina

2012-08-01

This research sought to extend knowledge about bystanders in bullying situations with a focus on the motivations that lead them to different responses. The 2 primary goals of this study were to investigate the reasons for children's decisions to help or not to help a victim when witnessing bullying, and to generate a grounded theory (or conceptual framework) of bystander motivation in bullying situations. Thirty students ranging in age from 9 to 15 years (M = 11.9; SD = 1.7) from an elementary and middle school in the southeastern United States participated in this study. Open- ended, semi-structured interviews were used, and sessions ranged from 30 to 45 minutes. We conducted qualitative methodology and analyses to gain an in-depth understanding of children's perspectives and concerns when witnessing bullying. A key finding was a conceptual framework of bystander motivation to intervene in bullying situations suggesting that deciding whether to help or not help the victim in a bullying situation depends on how bystanders define and evaluate the situation, the social context, and their own agency. Qualitative analysis revealed 5 themes related to bystander motives and included: interpretation of harm in the bullying situation, emotional reactions, social evaluating, moral evaluating, and intervention self-efficacy. Given the themes that emerged surrounding bystanders' motives to intervene or abstain from intervening, respondents reported 3 key elements that need to be confirmed in future research and that may have implications for future work on bullying prevention. These included: first, the potential importance of clear communication to children that adults expect bystanders to intervene when witnessing bullying; second, the potential of direct education about how bystanders can intervene to increase children's self-efficacy as defenders of those who are victims of bullying; and third, the assumption that it may be effective to encourage children's belief that

BYSTANDER EFFECTS GENOMIC INSTABILITY, ADAPTIVE RESPONSE AND CANCER RISK ASSESSMENT FOR RADIAION AND CHEMICAL EXPOSURES

EPA Science Inventory

BYSTANDER EFFECTS, GENOMIC INSTABILITY, ADAPTIVE RESPONSE AND CANCER RISK ASSESSMENT FOR RADIATION AND CHEMICAL EXPOSURES

R. Julian Preston
Environmental Carcinogenesis Division, U.S. Environmental Protection Agency, Research Triangle Park, N.C. 27711, USA

There ...

Getting angry matters: Going beyond perspective taking and empathic concern to understand bystanders' behavior in bullying.

PubMed

Pozzoli, Tiziana; Gini, Gianluca; Thornberg, Robert

2017-12-01

The present study examined the relations between different empathic dimensions and bystanders' behavior in bullying. Specifically, the indirect effects of empathic concern and perspective taking via empathic anger on defending and passive bystanding were tested in a sample of Italian young adolescents (N = 398; M age  = 12 years, 3 months, 47.2% girls). Path analysis confirmed the direct and indirect effects, via empathic anger, of empathic concern and perspective taking on bystanders' behavior, with the exception of the direct association between perspective taking and passive bystanding that was not significant. Our findings suggest that considering empathic anger together with empathic concern and perspective taking could help researchers to better understand the links between empathic dispositions and bystanders' behavior in bullying. Copyright © 2017. Published by Elsevier Ltd.

A correlation of long term effects and radiation quality in the progeny of bystander cells after microbeam radiations: The experimental study of radiotherapy for cancer risk mitigation

NASA Astrophysics Data System (ADS)

Autsavapromporn, N.; Konishi, T.; Liu, C.; Plante, I.; Funayama, T.; Usami, N.; Azzam, EI; Suzuki, M.

2017-06-01

The goal of this study is to investigate the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of delayed stressful effects in the progeny of bystander human skin fibroblasts cultures (NB1RGB). Briefly, confluent NB1RGB cells in the presence and absence of gap junction inhibitor (AGA) were exposed to ionizing radiation (IR) with a different linear energy transfer (LET) either 5.35 keV X rays (LET ∼6 keV/μm) or 18.3 MeV/u carbon (LET ∼103 keV/μm) microbeam radiations. Following 20 populations post-irradiation, the progeny of bystander NB1RGB cells were harvested and assayed for several of biological endpoints. Our results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET. The progeny of bystander cells exposed to low-LET X rays showed the persistence of oxidative stress and it was correlated with the increased mutant fraction. Such effect were not observed after high-LET carbon ions. Interestingly, inhibition of GJIC mitigated the toxic effects in the progeny of bystander cells. Together, the results contribute to the understanding of the fundamental radiation biology relating to the high-LET carbon ions to mitigate cancer risk after radiotherapy. Furthermore, GJIC be considered as a critical mediator in the bystander mutagenic effect.

Action of methotrexate and tofacitinib on directly stimulated and bystander-activated lymphocytes.

PubMed

Piscianz, Elisa; Candilera, Vanessa; Valencic, Erica; Loganes, Claudia; Paron, Greta; De Iudicibus, Sara; Decorti, Giuliana; Tommasini, Alberto

2016-07-01

Chronic inflammation associated with autoimmune activation is characteristic of rheumatic diseases from childhood to adulthood. In recent decades, significant improvements in the treatment of these types of disease have been achieved using disease modifying anti-rheumatic drugs (DMARDs), such as methotrexate (MTX) and, more recently, using biologic inhibitors. The recent introduction of kinase inhibitors (for example, tofacitinib; Tofa) further increases the available ARDs. However, there are patients that do not respond to any treatment strategies, for whom combination therapies are proposed. The data regarding the combined action of different drugs is lacking and the knowledge of the mechanisms of ARDs and their actions upon pathogenic lymphocytes, which are hypothesized to sustain disease, is poor. An in vitro model of inflammation was developed in the current study, in which stimulated and unstimulated lymphocytes were cultured together, but tracked separately, to investigate the action of MTX and Tofa on the two populations. By analysing lymphocyte proliferation and activation, and cytokine secretion in the culture supernatants, it was established that, due to the presence of activated cells, unstimulated cells underwent a bystander activation that was modulated by the ARDs. Additionally, varying administration schedules were demonstrated to affect lymphocytes differently in vitro, either directly or via bystander activation. Furthermore, MTX and Tofa exerted different effects; while MTX showed an antiproliferative effect, Tofa marginally effected activation, although only a slight antiproliferative action, which could be potentiated by sequential treatment with MTX. Thus, it was hypothesized that these differences may be exploited in sequential therapeutic strategies, to maximize the anti‑rheumatic effect. These findings are notable and must be accounted for, as bystander‑activated cells in vivo could contribute to the spread of autoimmune activation

Dose Calculations for [131I] Meta-Iodobenzylguanidine-Induced Bystander Effects

PubMed Central

Gow, M. D.; Seymour, C. B.; Boyd, M.; Mairs, R. J.; Prestiwch, W. V.; Mothersill, C. E.

2014-01-01

Targeted radiotherapy is a potentially useful treatment for some cancers and may be potentiated by bystander effects. However, without estimation of absorbed dose, it is difficult to compare the effects with conventional external radiation treatment. Methods: Using the Vynckier – Wambersie dose point kernel, a model for dose rate evaluation was created allowing for calculation of absorbed dose values to two cell lines transfected with the noradrenaline transporter (NAT) gene and treated with [131I]MIBG. Results: The mean doses required to decrease surviving fractions of UVW/NAT and EJ138/NAT cells, which received medium from [131I]MIBG-treated cells, to 25 – 30% were 1.6 and 1.7 Gy respectively. The maximum mean dose rates achieved during [131I]MIBG treatment were 0.09 – 0.75 Gy/h for UVW/NAT and 0.07 – 0.78 Gy/h for EJ138/NAT. These were significantly lower than the external beam gamma radiation dose rate of 15 Gy/h. In the case of control lines which were incapable of [131I]MIBG uptake the mean absorbed doses following radiopharmaceutical were 0.03 – 0.23 Gy for UVW and 0.03 – 0.32 Gy for EJ138. Conclusion: [131I]MIBG treatment for ICCM production elicited a bystander dose-response profile similar to that generated by external beam gamma irradiation but with significantly greater cell death. PMID:24659931

Genetic Signatures of HIV-1 Envelope-mediated Bystander Apoptosis

PubMed Central

Joshi, Anjali; Lee, Raphael T. C.; Mohl, Jonathan; Sedano, Melina; Khong, Wei Xin; Ng, Oon Tek; Maurer-Stroh, Sebastian; Garg, Himanshu

2014-01-01

The envelope (Env) glycoprotein of HIV is an important determinant of viral pathogenesis. Several lines of evidence support the role of HIV-1 Env in inducing bystander apoptosis that may be a contributing factor in CD4+ T cell loss. However, most of the studies testing this phenomenon have been conducted with laboratory-adapted HIV-1 isolates. This raises the question of whether primary Envs derived from HIV-infected patients are capable of inducing bystander apoptosis and whether specific Env signatures are associated with this phenomenon. We developed a high throughput assay to determine the bystander apoptosis inducing activity of a panel of primary Envs. We tested 38 different Envs for bystander apoptosis, virion infectivity, neutralizing antibody sensitivity, and putative N-linked glycosylation sites along with a comprehensive sequence analysis to determine if specific sequence signatures within the viral Env are associated with bystander apoptosis. Our studies show that primary Envs vary considerably in their bystander apoptosis-inducing potential, a phenomenon that correlates inversely with putative N-linked glycosylation sites and positively with virion infectivity. By use of a novel phylogenetic analysis that avoids subtype bias coupled with structural considerations, we found specific residues like Arg-476 and Asn-425 that were associated with differences in bystander apoptosis induction. A specific role of these residues was also confirmed experimentally. These data demonstrate for the first time the potential of primary R5 Envs to mediate bystander apoptosis in CD4+ T cells. Furthermore, we identify specific genetic signatures within the Env that may be associated with the bystander apoptosis-inducing phenotype. PMID:24265318

Factors influencing Chinese university students' willingness to performing bystander cardiopulmonary resuscitation.

PubMed

Lu, Cui; Jin, Ying-Hui; Shi, Xiao-Tong; Ma, Wen-Jing; Wang, Yun-Yun; Wang, Wei; Zhang, Yao

2017-05-01

Low rates of bystander-initiated CPR are a major obstacle to improved survival rates, and the aim of this study is to elucidate the factors associated with university students' attitudes toward performing bystander CPR. Questionnaires were distributed to 18 universities across three metropolises in China. One question asking for respondents' attitudes toward performing bystander CPR was set as the dependent variable, and the logistic regression models were used to extract independent factors for respondents' attitudes toward performing bystander CPR. 2934 questionnaires were completed, with a response rate of 81.5%. Results suggested that predictors of willingness to perform bystander CPR were: previous experience of performing bystander CPR, higher self-perceived ability to perform bystander CPR properly after instruction, medicine and law discipline, male gender, not being the single child of their parents, higher participation in university societies, being used to taking decisive action immediately, less self-perceived life stress and higher self-perceived knowledge level of CPR. Persons having previous experience of performing bystander CPR and those who thought they would have the ability to perform bystander CPR properly are predominantly associated with willingness to perform bystander CPR. Psychological and cultural factors need further study. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Meta-Analysis of School-Based Bullying Prevention Programs' Effects on Bystander Intervention Behavior

ERIC Educational Resources Information Center

Polanin, Joshua R.; Espelage, Dorothy L.; Pigott, Therese D.

2012-01-01

This meta-analysis synthesized bullying prevention programs' effectiveness at increasing bystander intervention in bullying situations. Evidence from 12 school-based programs, involving 12,874 students, indicated that overall the programs were successful (Hedges's g = 0.20, 95% confidence interval [CI] = 0.11 to 0.29, p = 0.001), with larger…

Effects of repetitive or intensified instructions in telephone assisted, bystander cardiopulmonary resuscitation: an investigator-blinded, 4-armed, randomized, factorial simulation trial.

PubMed

van Tulder, R; Roth, D; Krammel, M; Laggner, R; Heidinger, B; Kienbacher, C; Novosad, H; Chwojka, C; Havel, C; Sterz, F; Schreiber, W; Herkner, H

2014-01-01

Compression depth is frequently suboptimal in cardiopulmonary resuscitation (CPR). We investigated effects of intensified wording and/or repetitive target depth instructions on compression depth in telephone-assisted, protocol driven, bystander CPR on a simulation manikin. Thirty-two volunteers performed 10 min of compression only-CPR in a prospective, investigator-blinded, 4-armed, factorial setting. Participants were randomized either to standard wording ("push down firmly 5 cm"), intensified wording ("it is very important to push down 5 cm every time") or standard or intensified wording repeated every 20s. Three dispatchers were randomized to give these instructions. Primary outcome was relative compression depth (absolute compression depth minus leaning depth). Secondary outcomes were absolute distance, hands-off times as well as BORG-scale and nine-hole peg test (NHPT), pulse rate and blood pressure to reflect physical exertion. We applied a random effects linear regression model. Relative compression depth was 35 ± 10 mm (standard) versus 31 ± 11 mm (intensified wording) versus 25 ± 8 mm (repeated standard) and 31 ± 14 mm (repeated intensified wording). Adjusted for design, body mass index and female sex, intensified wording and repetition led to decreased compression depth of 13 (95%CI -25 to -1) mm (p=0.04) and 9 (95%CI -21 to 3) mm (p=0.13), respectively. Secondary outcomes regarding intensified wording showed significant differences for absolute distance (43 ± 2 versus 20 (95%CI 3-37) mm; p=0.01) and hands-off times (60 ± 40 versus 157 (95%CI 63-251) s; p=0.04). In protocol driven, telephone-assisted, bystander CPR, intensified wording and/or repetitive target depth instruction will not improve compression depth compared to the standard instruction. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Modifiers of Neighbors' Bystander Intervention in Intimate Partner Violence: A Concept Mapping Study.

PubMed

Wee, Sara; Todd, Mary-Justine; Oshiro, Michael; Greene, Emily; Frye, Victoria

2016-03-01

Encouraging bystander intervention in intimate partner violence (IPV) against women is potentially an important method of reducing the prevalence of such violence in urban communities. Most existing research has been conducted on campuses and in relation to sexual violence among teens or young adults. Our understanding of which bystander behaviors are feasible is nascent, and our knowledge of which situational factors influence neighbors' self-reported willingness to intervene is underdeveloped. We conducted a concept mapping study to identify potential bystander intervention behaviors in IPV among neighbors in urban settings; we also assessed whether perceived feasibility and effectiveness of those behaviors varied by situational characteristics. Using data collected from 41 residents of a low-income New York City neighborhood in late 2011, concept mapping was used to create a conceptual map of the 74 behaviors identified by participants. We examined participant differences in mean feasibility (i.e., that the participants "could" or "would" enact a behavior), feasibility given two situational characteristics (if the couple was perceived to have a history of IPV, and if children were believed to be involved or present), and perceived effectiveness of bystander behaviors. Differences across select sociodemographic factors of participants were also analyzed. A 13-cluster solution emerged, with clusters of bystander behaviors grouped into four larger cluster areas: victim focused, parenting/education focused, perpetrator focused, and community involvement focused. Bivariate analyses revealed that participants rated the four cluster areas as more feasible when a child was believed to be involved. Male participants rated intervention as less feasible when the couple was believed to have a history of IPV. Participants who reported a history of IPV victimization rated all four cluster areas as less effective on average, as compared with participants without a history of

Bystander first aid in trauma - prevalence and quality: a prospective observational study.

PubMed

Bakke, H K; Steinvik, T; Eidissen, S-I; Gilbert, M; Wisborg, T

2015-10-01

Bystander first aid and basic life support can likely improve victim survival in trauma. In contrast to bystander first aid and out-of-hospital cardiac arrest, little is known about the role of bystanders in trauma response. Our aim was to determine how frequently first aid is given to trauma victims by bystanders, the quality of this aid, the professional background of first-aid providers, and whether previous first-aid training affects aid quality. We conducted a prospective 18-month study in two mixed urban-rural Norwegian counties. The personnel on the first ambulance responding to trauma calls assessed and documented first aid performed by bystanders using a standard form. A total of 330 trauma calls were included, with bystanders present in 97% of cases. Securing an open airway was correctly performed for 76% of the 43 patients in need of this first-aid measure. Bleeding control was provided correctly for 81% of 63 patients for whom this measure was indicated, and prevention of hypothermia for 62% of 204 patients. Among the first-aid providers studied, 35% had some training in first aid. Bystanders with documented first-aid training gave better first aid than those where first-aid training status was unknown. A majority of the trauma patients studied received correct pre-hospital first aid, but still there is need for considerable improvement, particularly hypothermia prevention. Previous first-aid training seems to improve the quality of first aid provided. The effect on patient survival needs to be investigated. © 2015 The Authors. The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Radiation quality dependence of signal transmission and bystander induced cell killing

NASA Astrophysics Data System (ADS)

Esposito, Giuseppe; Bertolotti, Alessia; Facoetti, Angelica; Grande, Sveva; Mariotti, Luca; Ottolenghi, Andrea; Ranza, Elena; Simone, Giustina; Sorrentino, Eugenio; Antonella Tabocchini, Maria

Low dose radiobiological studies have shown effects, observable in cells that are in the vicinity of irradiated cells, which are due to the release by irradiated cells of several cellular mediators among which Reactive Oxygen and Nitrogen Species (ROS, NRS), and cytokines are likely to play a key role. Despite the large number in the literature of studies on bystander effects induced by ionizing radiation the results are still conflicting, and further studies are therefore needed on the possible underlying mechanisms. The dependence on radiation quality deserve particular attention because bystander mechanisms are probably more important with high-LET irradi-ations, where many cells are not hit (bystander). Moreover, due to the different patterns of energy deposition, the cellular response to low LET and high LET radiation can be different. Understanding whether these cells can contribute to the adverse effects of low radiation doses in a radiation quality-dependent fashion might have important implications in risk estimates for both cancer induction and non-cancer diseases. In this context, we addressed to the study of the bystander induced cell killing after incubation with "conditioned medium" from primary human fibroblasts irradiated with 0.1 and 0.5 Gy of α-particles or γ-rays. Medium transfer was performed after 1h incubation from irradiation. The results have confirmed a reduction in clonogenic survival after incubation with medium from α-irradiated cells, independently of the dose; similar results were obtained after γ-irradiation, although in this case a slight dose depen-dence could be envisaged. Interleukin-6 (IL-6) and Interleukin-8 (IL-8) levels were measured in the conditioned medium collected up to 20 hours after irradiation with α-particles and γ-rays in the dose-range of 0.1-1.0 Gy, in parallel with evaluation of their receptor expression in irradi-ated and bystander cells. Concerning IL-6, we observed the strongest modulation of its release

Effects of a Rape Awareness Program on College Women: Increasing Bystander Efficacy and Willingness to Intervene

ERIC Educational Resources Information Center

Foubert, John D.; Langhinrichsen-Rohling, Jennifer; Brasfield, Hope; Hill, Brent

2010-01-01

An experimental study evaluated the efficacy of a sexual assault risk-reduction program on 279 college women that focused on learning characteristics of male perpetrators and teaching bystander intervention techniques. After seeing The Women's Program, participants reported significantly greater bystander efficacy and significantly greater…

A Bully's Bystanders Are Never Innocent

ERIC Educational Resources Information Center

Coloroso, Barbara

2005-01-01

Though they play the least active role, bystanders are a critical element in bullying. With peers looking on and providing at least tacit support, the bully is no longer acting alone. The bystanders have become allies to the point of magnifying the supposed negative attributes of the target. If the bullying cycle is to be broken, the role of the…

Booze, Bars, and Bystander Behavior: People Who Consumed Alcohol Help Faster in the Presence of Others

PubMed Central

van Bommel, Marco; van Prooijen, Jan-Willem; Elffers, Henk; Van Lange, Paul A. M.

2016-01-01

People help each other less often and less quickly when bystanders are present. In this paper, we propose that alcohol consumption could attenuate or reverse this so-called bystander effect. Alcohol impairs people cognitively and perceptually, leading them to think less about the presence of others and behave less inhibited. Moreover, alcohol makes people more prone to see the benefits of helping and not the costs. To provide an initial test of these lines of reasoning, we invited visitors of bars in Amsterdam to join our study at a secluded spot at the bar. We manipulated bystander presence, and at the end of the study, we measured alcohol consumption. When participants took their seats, the experimenter dropped some items. We measured how many items were picked up and how quickly participants engaged in helping. Results revealed that alcohol did not influence the bystander effect in terms of the amount of help given. But importantly, it did influence the bystander effect in terms of response times: people who consumed alcohol actually came to aid faster in the presence of others. PMID:26903929

Extracellular signaling through the microenvironment: a hypothesis relating carcinogenesis, bystander effects, and genomic instability

NASA Technical Reports Server (NTRS)

Barcellos-Hoff, M. H.; Brooks, A. L.; Chatterjee, A. (Principal Investigator)

2001-01-01

Cell growth, differentiation and death are directed in large part by extracellular signaling through the interactions of cells with other cells and with the extracellular matrix; these interactions are in turn modulated by cytokines and growth factors, i.e. the microenvironment. Here we discuss the idea that extracellular signaling integrates multicellular damage responses that are important deterrents to the development of cancer through mechanisms that eliminate abnormal cells and inhibit neoplastic behavior. As an example, we discuss the action of transforming growth factor beta (TGFB1) as an extracellular sensor of damage. We propose that radiation-induced bystander effects and genomic instability are, respectively, positive and negative manifestations of this homeostatic process. Bystander effects exhibited predominantly after a low-dose or a nonhomogeneous radiation exposure are extracellular signaling pathways that modulate cellular repair and death programs. Persistent disruption of extracellular signaling after exposure to relatively high doses of ionizing radiation may lead to the accumulation of aberrant cells that are genomically unstable. Understanding radiation effects in terms of coordinated multicellular responses that affect decisions regarding the fate of a cell may necessitate re-evaluation of radiation dose and risk concepts and provide avenues for intervention.

Factors associated with bystander behaviors of Korean youth in school bullying situations: A cross-sectional study.

PubMed

Yang, Seung Ae; Kim, Dong Hee

2017-08-01

The behaviors of bystanders can have important effects on their peers. The aim of this study was to identify psychosocial and contextual factors associated with 3 types of bystander behavior (bully followers, outsiders, and defenders of victims) among Korean youth. A descriptive and cross-sectional study was conducted among 416 7th and 8th-grade students from 1 middle school in Korea. The Rosenberg Self Esteem Scale, the Korean version of the Social Problem-Solving Inventory, and measurements of relationships with friends and teachers, empathy, concerns about being bullied, attitudes toward bullying, and bystander behaviors were all used in the assessment. Empathy, relationship of teachers, attitudes toward bullying, and concerns about being bullied were significantly associated with all 3 types of bystanders' behaviors. Although, self-esteem, social problem solving ability were significantly associated with just defender of victim behaviors. These results suggest that several significant factors to cultivate constructive bystander behaviors should be considered to develop effective antibullying intervention.

Grid therapy using high definition multileaf collimators: realizing benefits of the bystander effect.

PubMed

Peng, Valery; Suchowerska, Natalka; Rogers, Linda; Claridge Mackonis, Elizabeth; Oakes, Samantha; McKenzie, David R

2017-08-01

In microbeam radiotherapy (MRT), parallel arrays of high-intensity synchrotron x-ray beams achieve normal tissue sparing without compromising tumor control. Grid-therapy using clinical linacs has spatial modulation on a larger scale and achieves promising results for palliative treatments of bulky tumors. The availability of high definition multileaf collimators (HDMLCs) with 2.5 mm leaves provides an opportunity for grid-therapy to more closely approach MRT. However, challenges to the wider implementation of grid-therapy remain because spatial modulation of the target volume runs counter to current radiotherapy practice and mechanisms for the beneficial effects of MRT are not fully understood. Without more knowledge of cell dose responses, a quantitative basis for planning treatments is difficult. The aim of this study is to determine if therapeutic benefits of MRT can be achieved using a linac with HDMLCs and if so, to develop a predictive model to support treatment planning. HD120-MLCs of a Varian Novalis TX TM were used to generate grid patterns of 2.5 and 5.0 mm spacing, which were characterized dosimetrically using Gafchromic TM EBT3 film. Clonogenic survival of normal (HUVEC) and cancer (NCI-H460, HCC-1954) cell lines following irradiation under the grid and open fields using a 6 MV photon beam were compared in-vitro for the same average dose. Relative to an open field, survival of normal cells in a 2.5 mm striped field was the same, while the survival of both cancer cell lines was significantly lower. A mathematical model was developed to incorporate dose gradients of the spatial modulation into the standard linear quadratic model. Our new bystander extended LQ model assumes spatial gradients drive the diffusion of soluble factors that influence survival through bystander effects, successfully predicting the experimental results that show an increased therapeutic ratio. Our results challenge conventional radiotherapy practice and propose that

Variations in Involvement: Motivating Bystanders to Care for Senior Citizens.

PubMed

Keller, Sarah N; Wilkinson, Tim

2017-01-01

The purpose of this study was to determine the impact of a senior service advertising campaign designed to increase volunteerism and financial donations among bystanders. A cross-sectional mail survey was administered to 2,500 adults; 384 usable responses were obtained. Survey responses were analyzed by level of exposure and involvement in senior care. High involvement individuals viewed the ads more favorably and exhibited stronger senior caretaking intentions. Low-involvement consumers were less likely to see their own potential contributions to senior care services as effective. It is argued that nonparticipants in prosocial helping may fail to notice the need (low awareness), fail to view the cause as urgent (low perceived susceptibility), or have low prior experience with the issue. A typology of involvement could be developed that can be used for audience segmentation in marketing health behaviors to bystanders. With limited theoretical and practical guidance on how to motivate bystanders to engage in prosocial behaviors, health communicators and marketers are challenged to tap into the vital resource that bystanders potentially could provide. The research reviewed and presented here indicates hope for engaging the public to become active players in making the nation a safer and healthier place.

“Protective Bystander Effects Simulated with the State-Vector Model”—HeLa x Skin Exposure to 137Cs Not Protective Bystander Response But Mammogram and Diagnostic X-Rays Are

PubMed Central

Leonard, Bobby E.

2008-01-01

The recent Dose Response journal article “Protective Bystander Effects Simulated with the State-Vector Model” (Schollnberger and Eckl 2007) identified the suppressive (below natural occurring, zero primer dose, spontaneous level) dose response for HeLa x skin exposure to 137Cs gamma rays (Redpath et al 2001) as a protective Bystander Effect (BE) behavior. I had previously analyzed the Redpath et al (2001) data with a Microdose Model and conclusively showed that the suppressive response was from Adaptive Response (AR) radio-protection (Leonard 2005, 2007a). The significance of my microdose analysis has been that low LET radiation induced single (i.e. only one) charged particle traversals through a cell can initiate a Poisson distributed activation of AR radio-protection. The purpose of this correspondence is to clarify the distinctions relative to the BE and the AR behaviors for the Redpath groups 137Cs data, show conversely however that the Redpath group data for mammography (Ko et al 2004) and diagnostic (Redpath et al 2003) X-rays do conclusively reflect protective bystander behavior and also herein emphasize the need for radio-biologist to apply microdosimetry in planning and analyzing their experiments for BE and AR. Whether we are adamantly pro-LNT, adamantly anti-LNT or, like most of us, just simple scientists searching for the truth in radio-biology, it is important that we accurately identify our results, especially when related to the LNT hypothesis controversy. PMID:18846260

We need to include bystander first aid in trauma research.

PubMed

Bakke, Håkon Kvåle; Wisborg, Torben

2017-03-23

The chain of trauma survival is a concept that originated in the area of out-of-hospital cardiac arrest (OHCA) and was adapted to the treatment of trauma. In out-of-hospital cardiac arrest research into bystander first aid has resulted in improved outcome. Whereas, in trauma research the first link of the chain of survival is almost ignored. In OHCA, cardiopulmonary resuscitation (CPR) from bystanders has been subject of a vast amount of research, as well as measures and programs to raise the rate of bystander CPR to cardiac arrest victims. These efforts have resulted in improved survival. The research effort has been well grounded in the research community, as demonstrated by its natural inclusion in the uniform reporting template (Utstein) for the treatment of OHCA. In trauma the bystander may contribute by providing an open airway, staunch bleedings, or prevent hypothermia. In trauma however, while the chain of survival has been adopted along with it distinct links, including bystander first aid, the consensus-based uniform reporting template for trauma (the Utstein template) does not include the bystander first aid efforts. There is extremely little research on what first aid measures bystanders provide to trauma victims, and on what impact such measures have on outcome. An important step to improve research on bystander first aid in trauma would be to include this as part of the uniform reporting template for trauma CONCLUSION: The lack of research on bystander first aid makes the first link in the trauma chain of survival the weakest link. We, the trauma research community, should either improve our research and knowledge in this area, or remove the link from the chain of survival.

Action Research Evaluation of Bystander Intervention Training Created by Munche, Stern, and O'Brien

ERIC Educational Resources Information Center

Shiflet, Jacqueline H.

2013-01-01

This qualitative, appreciative inquiry study was an examination of bystander intervention as related to sexual assault in the military. The purpose of the study was to examine how military personnel and Department of Defense civilian employees reflecting diverse backgrounds perceived the effectiveness of bystander intervention training and sexual…

Moral Disengagement among Bystanders to School Bullying

ERIC Educational Resources Information Center

Obermann, Marie-Louise

2011-01-01

This study examined the use of moral disengagement among children indirectly involved in bullying (bystanders). A sample of Danish adolescents (N = 660, M age 12.6 years) were divided into four groups depending on their bystander status: (a) outsiders, who did not experience bullying among their peers; (b) defenders, who were likely to help the…

Virtual bystanders in a language lesson: examining the effect of social evaluation, vicarious experience, cognitive consistency and praising on students' beliefs, self-efficacy and anxiety in a virtual reality environment.

PubMed

Qu, Chao; Ling, Yun; Heynderickx, Ingrid; Brinkman, Willem-Paul

2015-01-01

Bystanders in a real world's social setting have the ability to influence people's beliefs and behavior. This study examines whether this effect can be recreated in a virtual environment, by exposing people to virtual bystanders in a classroom setting. Participants (n = 26) first witnessed virtual students answering questions from an English teacher, after which they were also asked to answer questions from the teacher as part of a simulated training for spoken English. During the experiment the attitudes of the other virtual students in the classroom was manipulated; they could whisper either positive or negative remarks to each other when a virtual student was talking or when a participant was talking. The results show that the expressed attitude of virtual bystanders towards the participants affected their self-efficacy, and their avoidance behavior. Furthermore, the experience of witnessing bystanders commenting negatively on the performance of other students raised the participants' heart rate when it was their turn to speak. Two-way interaction effects were also found on self-reported anxiety and self-efficacy. After witnessing bystanders' positive attitude towards peer students, participants' self-efficacy when answering questions received a boost when bystanders were also positive towards them, and a blow when bystanders reversed their attitude by being negative towards them. Still, inconsistency, instead of consistency, between the bystanders' attitudes towards virtual peers and the participants was not found to result in a larger change in the participants' beliefs. Finally the results also reveal that virtual flattering or destructive criticizing affected the participants' beliefs not only about the virtual bystanders, but also about the neutral teacher. Together these findings show that virtual bystanders in a classroom can affect people's beliefs, anxiety and behavior.

A High School-Based Evaluation of TakeCARE, a Video Bystander Program to Prevent Adolescent Relationship Violence.

PubMed

Sargent, Kelli S; Jouriles, Ernest N; Rosenfield, David; McDonald, Renee

2017-03-01

Although bystander programs to prevent relationship and sexual violence have been evaluated with college students, few evaluations have been conducted with high school students. This study evaluated the effectiveness of TakeCARE, a brief video bystander program designed to promote helpful bystander behavior in situations involving relationship violence among high school students. Students (N = 1295; 52.5% female; 72.3% Hispanic) reported their bystander behavior at a baseline assessment. Classrooms (N = 66) were randomized to view TakeCARE or to a control condition, and high school counselors administered the video in the classrooms assigned to view TakeCARE. Students again reported their bystander behavior at a follow-up assessment approximately 3 months afterward. Results indicate that students who viewed TakeCARE reported more helpful bystander behavior at the follow-up assessment than students in the control condition. Results of exploratory analyses of the likelihood of encountering and intervening upon specific situations calling for bystander behavior are also reported. TakeCARE is efficacious when implemented in an urban high school by high school counselors.

Raising a Red Flag on Dating Violence: Evaluation of a Low-Resource, College-Based Bystander Behavior Intervention Program.

PubMed

Borsky, Amanda E; McDonnell, Karen; Turner, Monique Mitchell; Rimal, Rajiv

2016-03-09

Encouraging bystanders to intervene safely and effectively in situations that could escalate to violence-known as bystander behavior programs-is a growing yet largely untested strategy to prevent dating violence. Using a quasi-experimental design, we evaluate a low-resource, low-intensity intervention aimed at preventing dating violence among college students. The integrated behavioral model (IBM) was used to guide the evaluation. We also assess which IBM variables were most strongly associated with bystander behaviors. Participants were drawn from two Virginia colleges that predominantly train females in the health profession sciences. The intervention group (n = 329) participated in a university-wide bystander behavior intervention consisting of a 30-min presentation on dating violence at new-student orientation and a week-long "red flag" social marketing campaign on campus to raise awareness of dating violence. Controlling for changes at the comparison university, results showed an increase in bystander behaviors, such as encouraging a friend who may be in an abusive relationship to get help, after the intervention and adjusting for potential confounders (increase of 1.41 bystander behaviors, p = .04). However, no significant changes were found for bystander intentions, self-efficacy, social norms, or attitudes related to dating violence from pre- to post-intervention. Self-efficacy had a direct relationship with bystander behaviors. Results suggest that low-resource interventions have a modest effect on increasing bystander behaviors. However, higher resource interventions likely are needed for a larger impact, especially among students who already demonstrate strong baseline intentions to intervene and prevent dating violence. © The Author(s) 2016.

Variations in Involvement: Motivating Bystanders to Care for Senior Citizens

PubMed Central

Keller, Sarah N.; Wilkinson, Tim

2017-01-01

Purpose The purpose of this study was to determine the impact of a senior service advertising campaign designed to increase volunteerism and financial donations among bystanders. Design/methodology/approach A cross-sectional mail survey was administered to 2,500 adults; 384 usable responses were obtained. Survey responses were analyzed by level of exposure and involvement in senior care. Findings High involvement individuals viewed the ads more favorably and exhibited stronger senior caretaking intentions. Low-involvement consumers were less likely to see their own potential contributions to senior care services as effective. Results/implications It is argued that nonparticipants in prosocial helping may fail to notice the need (low awareness), fail to view the cause as urgent (low perceived susceptibility), or have low prior experience with the issue. Practical implications A typology of involvement could be developed that can be used for audience segmentation in marketing health behaviors to bystanders. Originality With limited theoretical and practical guidance on how to motivate bystanders to engage in prosocial behaviors, health communicators and marketers are challenged to tap into the vital resource that bystanders potentially could provide. The research reviewed and presented here indicates hope for engaging the public to become active players in making the nation a safer and healthier place. PMID:28824705

Friends, strangers, and bystanders: Informal practices of sexual assault intervention.

PubMed

Wamboldt, Alexander; Khan, Shamus R; Mellins, Claude Ann; Hirsch, Jennifer S

2018-05-07

Sexual assault is a part of many students' experiences in higher education. In U.S. universities, one in four women and one in ten men report being sexually assaulted before graduation. Bystander training programmes have been shown to modestly reduce campus sexual assault. Like all public health interventions, however, they have unintended social consequences; this research examines how undergraduate men on one campus understand bystander interventions and how those understandings shape their actual practices. We draw on ethnographic data collected between August 2015 and January 2017 at Columbia University and Barnard College. Our findings show that university training and an earnest desire to be responsible lead many men to intervene in possible sexual assaults. However, students' gendered methods target more socially vulnerable and socially distant men while protecting popular men and those to whom they are socially connected. Students' actual bystander practices thus reproduce social hierarchies in which low prestige may or may not be connected to actual risks of sexual assault. These results suggest that understanding intragroup dynamics and social hierarchies is essential to assault prevention in universities and that students' actions as bystanders may be effective at preventing assaults in some circumstances but may lead to new risks of sexual assault.

Impact of neighbourhood socio-economic status on bystander cardiopulmonary resuscitation in Paris.

PubMed

Dahan, Benjamin; Jabre, Patricia; Karam, Nicole; Misslin, Renaud; Tafflet, Muriel; Bougouin, Wulfran; Jost, Daniel; Beganton, Frankie; Marijon, Eloi; Jouven, Xavier

2017-01-01

No European data currently describe the relation between neighbourhood socio-economic status (SES) and rates of out-of-hospital cardiac arrest (OHCA) bystander cardiopulmonary resuscitation (CPR). This study aims to analyse this effect with a robust deprivation index. Data about all OHCA in Paris were collected prospectively between 2000 and 2010. A geographical neighbourhood unit was assigned to each case. Median household income, and rates of blue-collar workers, unemployment, and adults without high school diplomas were selected as SES characteristics and used to classify neighbourhoods as low SES or higher SES. We analysed the relationship between neighbourhood SES characteristics and the probability of receiving bystander CPR. Of the 4009 OHCA with mappable addresses recorded, 777 (19.4%) received bystander CPR. Compared to OHCA who did not receive bystander CPR, those receiving CPR were significantly more likely to have occurred in public locations, have had a witness to their OHCA, and not to have collapsed in a low SES neighbourhood, or in a neighbourhood with a median household income in the lowest quartile and with rates of no high school diplomas and blue-collar workers in the highest quartile. In the multilevel analyses, bystander CPR provision was significantly less frequent in low than in higher SES neighbourhoods (OR 0.85; 95% confidence interval [CI] 0.72-0.99). In the city of Paris, OHCA victims were less likely to receive bystander CPR in low SES neighbourhoods. These first European data are consistent with observations in North America and Asia. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The influence of smoking on radiation-induced bystander signal production in esophageal cancer patients.

PubMed

Hanu, C; Timotin, E; Wong, R; Sur, R K; Hayward, J E; Seymour, C B; Mothersill, C E

2016-05-01

The relevance of radiation-induced bystander effects in humans is unclear. Much of the existing data relate to cell lines but the effect of bystander signals in complex human tissues is unclear. A phase II clinical study was untaken, where blood sera from 60 patients along with 15 cancer-free volunteers were used to detect whether measurable bystander factor(s) could be found in the blood following high dose rate (HDR) brachytherapy. Overall, there was no significant change in bystander signal production (measured in a human keratinocyte reporter system) before and after one treatment fraction of HDR brachytherapy (p>0.05). Further assessment of patient characteristics and environmental modifiable factors including smoking were also analyzed. Similar to previously published data, samples taken from smokers produced weaker signals compared to non-smokers (p<0.05). Although the number of non-smoking subjects was low, there was a clear decrease in cloning efficiency observed in keratinocyte cultures for these patients that requires further study. This study found that samples taken from smokers do not produce bystander signals, whereas samples taken from non-smokers can produce such signals following HDR brachytherapy. These findings highlight the importance of studying the interactions of multiple stressors including environmental modifiers with radiation, since some factors such as smoking may elicit protection in tumor cells which could counteract the effectiveness of radiation therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

Bystander programs addressing sexual violence on college campuses: A systematic review and meta-analysis of program outcomes and delivery methods.

PubMed

Jouriles, Ernest N; Krauss, Alison; Vu, Nicole L; Banyard, Victoria L; McDonald, Renee

2018-02-06

This systematic review and meta-analysis evaluates the effectiveness of bystander programs that address sexual violence on college campuses. Program effects on student attitudes/beliefs and bystander behavior were examined. Durability of program outcomes and the influence of program-delivery methods (e.g., facilitator-led programs vs. video, online or poster campaign programs) and program-parameters (e.g., program length) were also evaluated. Twenty-four studies met criteria for inclusion in the meta-analysis, and 207 separate results from these studies were coded. Students who participated in a bystander program, compared to those who had not, had more pro-social attitudes/beliefs about sexual violence and intervening to prevent it, and engaged in more bystander behavior. Program effects diminished over time, but meaningful changes persisted for at least three months following program delivery. Longer programs had greater effects than shorter programs on attitudes/beliefs. Bystander programs can be a valuable addition to colleges' violence prevention efforts.

Nitric oxide-mediated bystander signal transduction induced by heavy-ion microbeam irradiation

NASA Astrophysics Data System (ADS)

Tomita, Masanori; Matsumoto, Hideki; Funayama, Tomoo; Yokota, Yuichiro; Otsuka, Kensuke; Maeda, Munetoshi; Kobayashi, Yasuhiko

2015-07-01

In general, a radiation-induced bystander response is known to be a cellular response induced in non-irradiated cells after receiving bystander signaling factors released from directly irradiated cells within a cell population. Bystander responses induced by high-linear energy transfer (LET) heavy ions at low fluence are an important health problem for astronauts in space. Bystander responses are mediated via physical cell-cell contact, such as gap-junction intercellular communication (GJIC) and/or diffusive factors released into the medium in cell culture conditions. Nitric oxide (NO) is a well-known major initiator/mediator of intercellular signaling within culture medium during bystander responses. In this study, we investigated the NO-mediated bystander signal transduction induced by high-LET argon (Ar)-ion microbeam irradiation of normal human fibroblasts. Foci formation by DNA double-strand break repair proteins was induced in non-irradiated cells, which were co-cultured with those irradiated by high-LET Ar-ion microbeams in the same culture plate. Foci formation was suppressed significantly by pretreatment with an NO scavenger. Furthermore, NO-mediated reproductive cell death was also induced in bystander cells. Phosphorylation of NF-κB and Akt were induced during NO-mediated bystander signaling in the irradiated and bystander cells. However, the activation of these proteins depended on the incubation time after irradiation. The accumulation of cyclooxygenase-2 (COX-2), a downstream target of NO and NF-κB, was observed in the bystander cells 6 h after irradiation but not in the directly irradiated cells. Our findings suggest that Akt- and NF-κB-dependent signaling pathways involving COX-2 play important roles in NO-mediated high-LET heavy-ion-induced bystander responses. In addition, COX-2 may be used as a molecular marker of high-LET heavy-ion-induced bystander cells to distinguish them from directly irradiated cells, although this may depend on the time

LGBT Discrimination on Campus and Heterosexual Bystanders: Understanding Intentions to Intervene

ERIC Educational Resources Information Center

Dessel, Adrienne B.; Goodman, Kevin D.; Woodford, Michael R.

2017-01-01

Discrimination targeting lesbian, gay, bisexual, and transgender (LGBT) students on college campuses occurs. Bystander intervention is important in supporting targeted students and improving campus climate for LGBT students. Peer-familiarity context (i.e., who the bystander knows in the situation) can play a role in bystander intervention, but…

Critical role of gap junction communication, calcium and nitric oxide signaling in bystander responses to focal photodynamic injury.

PubMed

Calì, Bianca; Ceolin, Stefano; Ceriani, Federico; Bortolozzi, Mario; Agnellini, Andrielly H R; Zorzi, Veronica; Predonzani, Andrea; Bronte, Vincenzo; Molon, Barbara; Mammano, Fabio

2015-04-30

Ionizing and nonionizing radiation affect not only directly targeted cells but also surrounding "bystander" cells. The underlying mechanisms and therapeutic role of bystander responses remain incompletely defined. Here we show that photosentizer activation in a single cell triggers apoptosis in bystander cancer cells, which are electrically coupled by gap junction channels and support the propagation of a Ca2+ wave initiated in the irradiated cell. The latter also acts as source of nitric oxide (NO) that diffuses to bystander cells, in which NO levels are further increased by a mechanism compatible with Ca(2+)-dependent enzymatic production. We detected similar signals in tumors grown in dorsal skinfold chambers applied to live mice. Pharmacological blockade of connexin channels significantly reduced the extent of apoptosis in bystander cells, consistent with a critical role played by intercellular communication, Ca2+ and NO in the bystander effects triggered by photodynamic therapy.

Marketing defibrillation training programs and bystander intervention support.

PubMed

Sneath, Julie Z; Lacey, Russell

2009-01-01

This exploratory study identifies perceptions of and participation in resuscitation training programs, and bystanders' willingness to resuscitate cardiac arrest victims. While most of the study's participants greatly appreciate the importance of saving someone's life, many indicated that they did not feel comfortable assuming this role. The findings also demonstrate there is a relationship between type of victim and bystanders' willingness to intervene. Yet, bystander intervention discomfort can be overcome with cardiopulmonary resuscitation and defibrillation training, particularly when the victim is a coworker or stranger. Further implications of these findings are discussed and modifications to public access defibrillation (PAD) training programs' strategy and communications are proposed.

Human Lung Cancer Risks from Radon – Part I - Influence from Bystander Effects - A Microdose Analysis

PubMed Central

Leonard, Bobby E.; Thompson, Richard E.; Beecher, Georgia C.

2010-01-01

Since the publication of the BEIR VI report in 1999 on health risks from radon, a significant amount of new data has been published showing various mechanisms that may affect the ultimate assessment of radon as a carcinogen, at low domestic and workplace radon levels, in particular the Bystander Effect (BE) and the Adaptive Response radio-protection (AR). We analyzed the microbeam and broadbeam alpha particle data of Miller et al. (1995, 1999), Zhou et al. (2001, 2003, 2004), Nagasawa and Little (1999, 2002), Hei et al. (1999), Sawant et al. (2001a) and found that the shape of the cellular response to alphas is relatively independent of cell species and LET of the alphas. The same alpha particle traversal dose response behavior should be true for human lung tissue exposure to radon progeny alpha particles. In the Bystander Damage Region of the alpha particle response, there is a variation of RBE from about 10 to 35. There is a transition region between the Bystander Damage Region and Direct Damage Region of between one and two microdose alpha particle traversals indicating that perhaps two alpha particle “hits” are necessary to produce the direct damage. Extrapolation of underground miners lung cancer risks to human risks at domestic and workplace levels may not be valid. PMID:21731539

Beyond Yes or No: Understanding Undergraduate Students' Responses as Bystanders to Sexual Assault Risk Situations.

PubMed

Hoxmeier, Jill C; McMahon, Sarah; O'Connor, Julia

2017-08-01

The White House Task Force to Protect Students From Sexual Assault recommends bystander engagement programming as part of campus sexual assault prevention efforts. Measuring students' bystander behavior, and thus, assessing the effectiveness of such programming, is a challenging endeavor due to the range of risk situations students may witness, as well as the nuances in potential barriers students may face in these situations. Currently, many studies include dichotomous measures of bystander behavior without gathering further information about students' opportunities to intervene, barriers to intervening, and intervention strategies. The current study sought to implement a more comprehensive approach to understanding the types of sexual assault risk situations students report to witness, as well as their response in those situations, reasons for not intervening, and any gender differences therein. In 2014, undergraduate students ( n = 9,358) at a large, public university in the Northeast completed a web-based survey to assess bystander opportunities and responses for six different risk situations. Results show that prosocial bystander responses varied depending on the risk situation. Of those students with opportunities to intervene, noninterveners reported the situation was "none of their business" or that they were "unsure of what to do." Interveners reported to have either "confronted the situation directly" or "went and got assistance." We also observed significant gender differences in students' reported intervention opportunities and bystander responses. The findings of this study have several important implications for bystander engagement programming and future research.

Peer bystanders to bullying: who wants to play with the victim?

PubMed

Howard, Anne M; Landau, Steven; Pryor, John B

2014-02-01

Given widespread concern associated with school-based bullying, researchers have looked beyond a dyadic perspective (i.e., bullies and victims only), and now consider the broader social ecology of the peer group. In this research, we examined how the behaviors of peer bystanders influence subsequent reactions to bullies and their victims. Two hundred and six 10- to 15-year-old boys (Mage = 12.46) were invited to play a computer game with three other boys allegedly located at another school. Before the start of the game, participants "met the other players" apparently sitting in a waiting room. These child actors depicted an escalating bullying episode in which the behavior of the bystander was manipulated: aide to the bully, defender of the victim, or passive outsider. Immediately after exposure to the bullying, each participant played a ball toss game (Cyberball) with the three other boys in the video. Individual differences among participants were examined as moderators of the effect of bystander behavior on participants' willingness to include the "victim" in the game. Results indicated that, when exposed to a passive bystander, boys' normative beliefs about aggression, as well as their tendency to morally disengage from observed egregious acts, decreased their willingness to include the victim in the game.

Bystander Intervention Prior to The Arrival of Emergency Medical Services: Comparing Assistance across Types of Medical Emergencies.

PubMed

Faul, Mark; Aikman, Shelley N; Sasser, Scott M

2016-01-01

situational factors and the type of medical emergency. A higher risk of patient death is likely to prompt bystander action. These novel study results can lead to more effective first aid training programs. bystander; EMS; rural; cardiac distress; trauma.

Changes in vocal parameters with social context in humpback whales: considering the effect of bystanders.

PubMed

Dunlop, Rebecca A

Many theories and communication models developed from terrestrial studies focus on a simple dyadic exchange between a sender and receiver. During social interactions, the "frequency code" hypothesis suggests that frequency characteristics of vocal signals can simultaneously encode for static signaler attributes (size or sex) and dynamic information, such as motivation or emotional state. However, the additional presence of a bystander may result in a change of signaling behavior if the costs and benefits associated with the presence of this bystander are different from that of a simple dyad. In this study, two common humpback whale social calls ("wops" and "grumbles") were tested for differences related to group social behavior and the presence of bystanders. "Wop" parameters were stable with group social behavior, but were emitted at lower (14 dB) levels in the presence of a nearby singing whale compared to when a singing whale was not in the area. "Grumbles" were emitted at lower (30-39 Hz) fundamental frequencies in affiliative compared to non-affiliative groups and, in the presence of a nearby singing whale, were also emitted at lower (14 dB) levels. Vocal rates did not significantly change. The results suggest that, in humpbacks, the frequency in certain sound types relates to the social behavior of the vocalizing group, implying a frequency code system. The presence of a nearby audible bystander (a singing whale) had no effect on this frequency code, but by reducing their acoustic level, the signal-to-noise ratio at the singer would have been below 0, making it difficult for the singer to audibly detect the group. The frequency, duration, and amplitude parameters of humpback whale social vocalizations were tested between different social contexts: group social behavior (affiliating versus non-affiliating), the presence of a nearby singing whale, and the presence of a nearby non-singing group. "Grumbles" (commonly heard low-frequency unmodulated sounds

Implications for sexual assault prevention: college students as prosocial bystanders.

PubMed

Exner, Deinera; Cummings, Nina

2011-01-01

Prosocial bystander interventions are promising approaches to sexual assault prevention on college campuses. To assess bystander attitudes among undergraduate students at a northeastern university. A convenience sample of 188 students from 4 undergraduate classes was surveyed during regularly scheduled class sessions. Participants completed a short survey on bystander efficacy, readiness to change, and barriers to intervention prior to the start of class. The majority of students were not involved in activities or programs focused on sexual assault prevention. Although students agreed that violence could be prevented, they perceived many barriers to their own participation in intervention. There is a need for gender-targeted prevention programming that introduces the idea of prosocial bystander intervention, with a focus on increasing self-efficacy and lowering barriers.

Risk Factors Associated with Peer Victimization and Bystander Behaviors among Adolescent Students.

PubMed

Huang, Zepeng; Liu, Zhenni; Liu, Xiangxiang; Lv, Laiwen; Zhang, Yan; Ou, Limin; Li, Liping

2016-07-27

Despite the prevalence of the phenomena of peer victimization and bystander behaviors, little data has generated to describe their relationships and risk factors. In this paper, a self-administered survey using a cross-sectional cluster-random sampling method in a sample of 5450 participants (2734 girls and 2716 boys) between 4th and 11th grades was conducted at six schools (two primary schools and four middle schools) located in Shantou, China. Self-reported peer victimization, bystander behaviors and information regarding parents' risky behaviors and individual behavioral factors were collected. Multinomial logistic regression analysis was applied to evaluate risk factors affecting peer victimization and bystander behaviors. The results indicated that urban participants were more likely to become bullying victims but less likely to become passive bystanders. Contrarily, bullying victimization was related to the increasing of passive bystander behaviors. Father drinking and mother smoking as independent factors were risk factors for peer victimization. Participants who were smoking or drinking had a tendency to be involved in both peer victimization and passive bystander behaviors. This study suggested that bystander behaviors, victims' and parents' educations play a more important role in peer victimization than previously thought.

Human Lung Cancer Risks from Radon – Part II – Influence from Combined Adaptive Response and Bystander Effects – A Microdose Analysis

PubMed Central

Leonard, Bobby E.; Thompson, Richard E.; Beecher, Georgia C.

2010-01-01

In the prior Part I, the potential influence of the low level alpha radiation induced bystander effect (BE) on human lung cancer risks was examined. Recent analysis of adaptive response (AR) research results with a Microdose Model has shown that single low LET radiation induced charged particles traversals through the cell nucleus activates AR. We have here conducted an analysis based on what is presently known about adaptive response and the bystander effect (BE) and what new research is needed that can assist in the further evaluation human cancer risks from radon. We find that, at the UNSCEAR (2000) worldwide average human exposures from natural background and man-made radiations, the human lung receives about a 25% adaptive response protection against the radon alpha bystander damage. At the UNSCEAR (2000) minimum range of background exposure levels, the lung receives minimal AR protection but at higher background levels, in the high UNSCEAR (2000) range, the lung receives essentially 100% protection from both the radon alpha damage and also the endogenic, spontaneously occurring, potentially carcinogenic, lung cellular damage. PMID:22461760

The effect of basic life support education on laypersons' willingness in performing bystander hands only cardiopulmonary resuscitation.

PubMed

Cho, Gyu Chong; Sohn, You Dong; Kang, Ku Hyun; Lee, Won Woong; Lim, Kyung Soo; Kim, Won; Oh, Bum Jin; Choi, Dai Hai; Yeom, Seok Ran; Lim, Hoon

2010-06-01

Recently, hands only CPR (cardiopulmonary resuscitation) has been proposed as an alternative to standard CPR for bystanders. The present study was performed to identify the effect of basic life support (BLS) training on laypersons' willingness in performing standard CPR and hands only CPR. The participants for this study were non-medical personnel who applied for BLS training program that took place in 7 university hospitals in and around Korea for 6 months. Before and after BLS training, all the participants were given questionnaires for bystander CPR, and 890 respondents were included in the final analyses. Self-assessed confidence score for bystander CPR, using a visual analogue scale from 0 to 100, increased from 51.5+/-30.0 before BLS training to 87.0+/-13.7 after the training with statistical significance (p 0.001). Before the training, 19% of respondents reported willingness to perform standard CPR on a stranger, and 30.1% to perform hands only CPR. After the training, this increased to 56.7% of respondents reporting willingness to perform standard CPR, and 71.9%, hands only CPR, on strangers. Before and after BLS training, the odds ratio of willingness to perform hands only CPR versus standard CPR were 1.8 (95% CI 1.5-2.3) and 2.0 (95% CI 1.7-2.6) for a stranger, respectively. Most of the respondents, who reported they would decline to perform standard CPR, stated that fear of liability and fear of disease transmission were deciding factors after the BLS training. The BLS training increases laypersons' confidence and willingness to perform bystander CPR on a stranger. However, laypersons are more willing to perform hands only CPR rather than to perform standard CPR on a stranger regardless of the BLS training. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Student Voices: What Can Bystanders Do to Prevent Bullying of Students Who Are Different (or Perceived as Different) from Others?

ERIC Educational Resources Information Center

Nordseth, Anna; Vepachedu, Vikas; Shipman, Grant; Alayachew, David

2012-01-01

In this article, four students share their ideas on what bystanders can do to prevent bullying of students who are different or perceived as different from others. Anna Nordseth says what bystanders need to realize is how to recognize bullying and what a lasting effect it can have on the individuals involved. One bold, compassionate bystander can…

Determinants of self-reported bystander behavior in cyberbullying incidents amongst adolescents.

PubMed

DeSmet, Ann; Veldeman, Charlene; Poels, Karolien; Bastiaensens, Sara; Van Cleemput, Katrien; Vandebosch, Heidi; De Bourdeaudhuij, Ilse

2014-04-01

This study explores behavioral determinants of self-reported cyberbullying bystander behavior from a behavioral change theoretical perspective, to provide levers for interventions. Nine focus groups were conducted with 61 young adolescents (aged 12-16 years, 52% girls). Assertive defending, reporting to others, providing advice, and seeking support were the most mentioned behaviors. Self-reported bystander behavior heavily depended on contextual factors, and should not be considered a fixed participant role. Bystanders preferred to handle cyberbullying offline and in person, and comforting the victim was considered more feasible than facing the bully. Most prevailing behavioral determinants to defend or support the victim were low moral disengagement, that the victim is an ingroup member, and that the bystander is popular. Youngsters felt they received little encouragement from their environment to perform positive bystanding behavior, since peers have a high acceptance for not defending and perceived parental support for defending behavior is largely lacking. These results suggest multilevel models for cyberbullying research, and interventions are needed. With much previous research into cyberbullying insufficiently founded in theoretical models, the employed framework of the Integrative Model and Social Cognitive Theory may inspire future studies into bystander behavior.

Virtual Bystanders in a Language Lesson: Examining the Effect of Social Evaluation, Vicarious Experience, Cognitive Consistency and Praising on Students' Beliefs, Self-Efficacy and Anxiety in a Virtual Reality Environment

PubMed Central

Qu, Chao; Ling, Yun; Heynderickx, Ingrid; Brinkman, Willem-Paul

2015-01-01

Bystanders in a real world's social setting have the ability to influence people’s beliefs and behavior. This study examines whether this effect can be recreated in a virtual environment, by exposing people to virtual bystanders in a classroom setting. Participants (n = 26) first witnessed virtual students answering questions from an English teacher, after which they were also asked to answer questions from the teacher as part of a simulated training for spoken English. During the experiment the attitudes of the other virtual students in the classroom was manipulated; they could whisper either positive or negative remarks to each other when a virtual student was talking or when a participant was talking. The results show that the expressed attitude of virtual bystanders towards the participants affected their self-efficacy, and their avoidance behavior. Furthermore, the experience of witnessing bystanders commenting negatively on the performance of other students raised the participants’ heart rate when it was their turn to speak. Two-way interaction effects were also found on self-reported anxiety and self-efficacy. After witnessing bystanders’ positive attitude towards peer students, participants’ self-efficacy when answering questions received a boost when bystanders were also positive towards them, and a blow when bystanders reversed their attitude by being negative towards them. Still, inconsistency, instead of consistency, between the bystanders’ attitudes towards virtual peers and the participants was not found to result in a larger change in the participants’ beliefs. Finally the results also reveal that virtual flattering or destructive criticizing affected the participants’ beliefs not only about the virtual bystanders, but also about the neutral teacher. Together these findings show that virtual bystanders in a classroom can affect people’s beliefs, anxiety and behavior. PMID:25884211

A heterotypic bystander effect for tumor cell killing after adeno-associated virus/phage-mediated, vascular-targeted suicide gene transfer.

PubMed

Trepel, Martin; Stoneham, Charlotte A; Eleftherohorinou, Hariklia; Mazarakis, Nicholas D; Pasqualini, Renata; Arap, Wadih; Hajitou, Amin

2009-08-01

Suicide gene transfer is the most commonly used cytotoxic approach in cancer gene therapy; however, a successful suicide gene therapy depends on the generation of efficient targeted systemic gene delivery vectors. We recently reported that selective systemic delivery of suicide genes such as herpes simplex virus thymidine kinase (HSVtk) to tumor endothelial cells through a novel targeted adeno-associated virus/phage vector leads to suppression of tumor growth. This marked effect has been postulated to result primarily from the death of cancer cells by hypoxia following the targeted disruption of tumor blood vessels. Here, we investigated whether an additional mechanism of action is involved. We show that there is a heterotypic "bystander" effect between endothelial cells expressing the HSVtk suicide gene and tumor cells. Treatment of cocultures of HSVtk-transduced endothelial cells and non-HSVtk-transduced tumor cells with ganciclovir results in the death of both endothelial and tumor cells. Blocking of this effect by 18alpha-glycyrrhetinic acid indicates that gap junctions between endothelial and tumor cells are largely responsible for this phenomenon. Moreover, the observed bystander killing is mediated by connexins 43 and 26, which are expressed in endothelial and tumor cell types. Finally, this heterotypic bystander effect is accompanied by a suppression of tumor growth in vivo that is independent of primary gene transfer into host-derived tumor vascular endothelium. These findings add an alternative nonmutually exclusive and potentially synergistic cytotoxic mechanism to cancer gene therapy based on targeted adeno-associated virus/phage and further support the promising role of nonmalignant tumor stromal cells as therapeutic targets.

Prosocial Bystander Behavior in Bullying Dynamics: Assessing the Impact of Social Capital.

PubMed

Evans, Caroline B R; Smokowski, Paul R

2015-12-01

Individuals who observe a bullying event, but are not directly involved as a bully or victim, are referred to as bystanders. Prosocial bystanders are those individuals who actively intervene in bullying dynamics to support the victim and this prosocial behavior often ends the bullying. The current study examines how social capital in the form of social support, community engagement, mental health functioning, and positive school experiences and characteristics is associated with the likelihood of engaging in prosocial bystander behavior in a large sample (N = 5752; 51.03% female) of racially/ethnically diverse rural youth. It was hypothesized that social capital would be associated with an increased likelihood of engaging in prosocial bystander behavior. Following multiple imputation, an ordered logistic regression with robust standard errors was run. The hypothesis was partially supported and results indicated that social capital in the form of friend and teacher support, ethnic identity, religious orientation, and future optimism were significantly associated with an increased likelihood of engaging in prosocial bystander behavior. Contrary to the hypothesis, a decreased rate of self-esteem was significantly associated with an increased likelihood of engaging in prosocial bystander behavior. The findings highlight the importance of positive social relationships and community engagement in increasing prosocial bystander behavior and ultimately decreasing school bullying. Implications were discussed.

Bystander Intervention Prior to The Arrival of Emergency Medical Services: Comparing Assistance across Types of Medical Emergencies

PubMed Central

Faul, Mark; Aikman, Shelley N.; Sasser, Scott M.

2016-01-01

.57–1.71). Conclusion Bystander intervention varies greatly on situational factors and the type of medical emergency. A higher risk of patient death is likely to prompt bystander action. These novel study results can lead to more effective first aid training programs. PMID:26807490

A Pragmatic Study of Relational Identity in Bystander Intervention

ERIC Educational Resources Information Center

Huang, Xu

2018-01-01

Given that intervention has been relatively under-researched in pragmatics, this paper offers a linguistic-pragmatic examination of a case of bystander intervention, a notion which is generally known in social psychology. This study approaches the phenomenon of bystander intervention by analyzing discourse data transcribed from a video posted…

Measurement of the bystander intervention model for bullying and sexual harassment.

PubMed

Nickerson, Amanda B; Aloe, Ariel M; Livingston, Jennifer A; Feeley, Thomas Hugh

2014-06-01

Although peer bystanders can exacerbate or prevent bullying and sexual harassment, research has been hindered by the absence of a validated assessment tool to measure the process and sequential steps of the bystander intervention model. A measure was developed based on the five steps of Latané and Darley's (1970) bystander intervention model applied to bullying and sexual harassment. Confirmatory factor analysis with a sample of 562 secondary school students confirmed the five-factor structure of the measure. Structural equation modeling revealed that all the steps were influenced by the previous step in the model, as the theory proposed. In addition, the bystander intervention measure was positively correlated with empathy, attitudes toward bullying and sexual harassment, and awareness of bullying and sexual harassment facts. This measure can be used for future research and to inform intervention efforts related to the process of bystander intervention for bullying and sexual harassment. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

An Application of the Reasoned Action Approach to Bystander Intervention for Sexual Assault.

PubMed

Lukacena, Kaylee M; Reynolds-Tylus, Tobias; Quick, Brian L

2017-10-25

The high prevalence of sexual assault in US college campuses has led to a widespread implementation of bystander intervention programs aimed at preventing sexual assault. The current study examines predictors of college students' intentions to engage in bystander intervention through the theoretical lens of the reasoned action approach. An online survey with college students (N = 186) was conducted at a large Midwestern university. Our results indicated experiential attitudes, instrumental attitudes, descriptive norms, autonomy, and capacity, each positively associated with participants' intentions to intervene to stop a sexual assault. Against expectations, injunctive norms were unrelated to bystander intervention intentions. Finally, in addition to these main effects, an experiential attitude by autonomy interaction was also observed. The results are discussed with a focus on the theoretical and practical implications of our findings.

Bullying victimization and the social and emotional maladjustment of bystanders: A propensity score analysis.

PubMed

Werth, Jilynn M; Nickerson, Amanda B; Aloe, Ariel M; Swearer, Susan M

2015-08-01

This study investigated how bystanders, who have and have not been bullied, perceive their social and emotional maladjustment depending on the form of bullying (physical or verbal) they witness. Using propensity score matching, equivalent groups of 270 victimized and 270 non-victimized bystander groups were created based on middle school students' responses on the Bully Survey-Student Version (BYS-S; Swearer, 2001). Victimized bystanders experienced higher social maladjustment than non-victimized bystanders. Path analysis results suggest that social and emotional maladjustment as a bystander is related not only to social-emotional maladjustment as victim, but to gender and the form of bullying witnessed. The way in which bystanders are influenced by their personal victimization may be a critical factor in predicting, understanding, and increasing active bystander intervention. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Bystander's willingness to report theft, physical assault, and sexual assault: the impact of gender, anonymity, and relationship with the offender.

PubMed

Nicksa, Sarah C

2014-01-01

This research examines bystander willingness to report three different crimes to the police or campus authorities among a college student sample (n = 295). Twelve original vignettes varied anonymity when reporting, bystander's relationship with the offender (friend or stranger), and crime type. A factorial analysis of variance showed that main effects were found for crime type, bystander's gender, and bystander's relationship with the offender; anonymity was not significant. The physical assault was the most likely to be reported (4.47), followed by theft (3.26), and sexual assault (2.36). Women were more likely than men to report each crime type, and bystanders who were good friends of the offender were less likely to report than strangers. No two- or three-way interactions were significant, but a significant four-way interaction indicated that anonymity, relationship with the offender, and bystander's gender predicted willingness to report for the sexual assault scenario.

Bystander fatigue and CPR quality by older bystanders: a randomized crossover trial comparing continuous chest compressions and 30:2 compressions to ventilations.

PubMed

Liu, Shawn; Vaillancourt, Christian; Kasaboski, Ann; Taljaard, Monica

2016-11-01

This study sought to measure bystander fatigue and cardiopulmonary resuscitation (CPR) quality after five minutes of CPR using the continuous chest compression (CCC) versus the 30:2 chest compression to ventilation method in older lay persons, a population most likely to perform CPR on cardiac arrest victims. This randomized crossover trial took place at three tertiary care hospitals and a seniors' center. Participants were aged ≥55 years without significant physical limitations (frailty score ≤3/7). They completed two 5-minute CPR sessions (using 30:2 and CCC) on manikins; sessions were separated by a rest period. We used concealed block randomization to determine CPR method order. Metronome feedback maintained a compression rate of 100/minute. We measured heart rate (HR), mean arterial pressure (MAP), and Borg Exertion Scale. CPR quality measures included total number of compressions and number of adequate compressions (depth ≥5 cm). Sixty-three participants were enrolled: mean age 70.8 years, female 66.7%, past CPR training 60.3%. Bystander fatigue was similar between CPR methods: mean difference in HR -0.59 (95% CI -3.51-2.33), MAP 1.64 (95% CI -0.23-3.50), and Borg 0.46 (95% CI 0.07-0.84). Compared to 30:2, participants using CCC performed more chest compressions (480.0 v. 376.3, mean difference 107.7; p<0.0001) and more adequate chest compressions (381.5 v. 324.9, mean difference. 62.0; p=0.0001), although good compressions/minute declined significantly faster with the CCC method (p=0.0002). CPR quality decreased significantly faster when performing CCC compared to 30:2. However, performing CCC produced more adequate compressions overall with a similar level of fatigue compared to the 30:2 method.

Bystander Approaches: Empowering Students to Model Ethical Sexual Behavior

ERIC Educational Resources Information Center

Lynch, Annette; Fleming, Wm. Michael

2005-01-01

Sexual violence on college campuses is well documented. Prevention education has emerged as an alternative to victim-- and perpetrator--oriented approaches used in the past. One sexual violence prevention education approach focuses on educating and empowering the bystander to become a point of ethical intervention. In this model, bystanders to…

Critical role of gap junction communication, calcium and nitric oxide signaling in bystander responses to focal photodynamic injury

PubMed Central

Calì, Bianca; Ceolin, Stefano; Ceriani, Federico; Bortolozzi, Mario; Agnellini, Andrielly H.R.; Zorzi, Veronica; Predonzani, Andrea; Bronte, Vincenzo

2015-01-01

Ionizing and nonionizing radiation affect not only directly targeted cells but also surrounding “bystander” cells. The underlying mechanisms and therapeutic role of bystander responses remain incompletely defined. Here we show that photosentizer activation in a single cell triggers apoptosis in bystander cancer cells, which are electrically coupled by gap junction channels and support the propagation of a Ca2+ wave initiated in the irradiated cell. The latter also acts as source of nitric oxide (NO) that diffuses to bystander cells, in which NO levels are further increased by a mechanism compatible with Ca2+-dependent enzymatic production. We detected similar signals in tumors grown in dorsal skinfold chambers applied to live mice. Pharmacological blockade of connexin channels significantly reduced the extent of apoptosis in bystander cells, consistent with a critical role played by intercellular communication, Ca2+ and NO in the bystander effects triggered by photodynamic therapy. PMID:25868859

Cyberbullying Among Adolescent Bystanders: Role of Affective Versus Cognitive Empathy in Increasing Prosocial Cyberbystander Behavior.

PubMed

Barlińska, Julia; Szuster, Anna; Winiewski, Mikołaj

2018-01-01

The purpose of this study was to investigate if affective (vicarious sharing of emotions) and cognitive empathy (mental perspective taking) induction may stimulate adolescent online bystanders' intervention in cyberbullying cases. The role of reporting the abuse is crucial because it is a form of active support to the victim, initiated by children, to stop the bullying. The effectiveness of empathy activation in decreasing negative cyberbystander reinforcing behavior has been proved in previous studies. The effects of affective and cognitive empathy activation on positive cyberbystander behavior, defined as reporting the bullying online, were explored in two follow-up studies N = 271 and N = 265. The influence of experiencing cyberbullying as perpetrator, victim, and as determined by gender on prosocial cyberbystander behavior was also controlled. The results indicate that only cognitive empathy activation increases the likelihood of intervening bystander behavior. Neither affective empathy induction, previous experience of cyberperpetration, cybervictimization, nor gender affected the engagement in prosocial bystander behavior. The conclusion of the research is that a program consequently activating more reflective cognitive empathy induction can contribute toward the establishment of healthier behavioral patterns among bystanders to cyberbullying, increasing the probability of their reporting the cyberbullying acts.

Addressing bystander exposure to agricultural pesticides in life cycle impact assessment.

PubMed

Ryberg, Morten Walbech; Rosenbaum, Ralph K; Mosqueron, Luc; Fantke, Peter

2018-04-01

Residents living near agricultural fields may be exposed to pesticides drifting from the fields after application to different field crops. To address this currently missing exposure pathway in life cycle assessment (LCA), we developed a modeling framework for quantifying exposure of bystanders to pesticide spray drift from agricultural fields. Our framework consists of three parts addressing: (1) loss of pesticides from an agricultural field via spray drift; (2) environmental fate of pesticide in air outside of the treated field; and (3) exposure of bystanders to pesticides via inhalation. A comparison with measured data in a case study on pesticides applied to potato fields shows that our model gives good predictions of pesticide air concentrations. We compared our bystander exposure estimates with pathways currently included in LCA, namely aggregated inhalation and ingestion exposure mediated via the environment for the general population, and general population exposure via ingestion of pesticide residues in consumed food crops. The results show that exposure of bystanders is limited relative to total population exposure from ingestion of pesticide residues in crops, but that the exposure magnitude of individual bystanders can be substantially larger than the exposure of populations not living in the proximity to agricultural fields. Our framework for assessing bystander exposure to pesticide applications closes a relevant gap in the exposure assessment included in LCA for agricultural pesticides. This inclusion aids decision-making based on LCA as previously restricted knowledge about exposure of bystanders can now be taken into account. Copyright © 2018 Elsevier Ltd. All rights reserved.

Examining Variation in Adolescent Bystanders' Responses to Bullying

ERIC Educational Resources Information Center

Waasdorp, Tracy Evian; Bradshaw, Catherine P.

2018-01-01

Latent class analysis was used to examine whether patterns of bystander responses varied as a function of both student- and school-level characteristics. Data from 18,863 high school students from 58 schools who "ever witnessed bullying" were used to identify five latent classes of bystander behavior. Three of the classes identified…

Bystander Cardiopulmonary Resuscitation Is Clustered and Associated With Neighborhood Socioeconomic Characteristics: A Geospatial Analysis of Kent County, Michigan.

PubMed

Uber, Amy; Sadler, Richard C; Chassee, Todd; Reynolds, Joshua C

2017-08-01

Geographic clustering of bystander cardiopulmonary resuscitation (CPR) is associated with demographic and socioeconomic features of the community where out-of-hospital cardiac arrest (OHCA) occurred, although this association remains largely untested in rural areas. With a significant rural component and relative racial homogeneity, Kent County, Michigan, provides a unique setting to externally validate or identify new community features associated with bystander CPR. Using a large, countywide data set, we tested for geographic clustering of bystander CPR and its associations with community socioeconomic features. Secondary analysis of adult OHCA subjects (2010-2015) in the Cardiac Arrest Registry to Enhance Survival (CARES) data set for Kent County, Michigan. After linking geocoded OHCA cases to U.S. census data, we used Moran's I-test to assess for spatial autocorrelation of population-weighted cardiac arrest rate by census block group. Getis-Ord Gi statistic assessed for spatial clustering of bystander CPR and mixed-effects hierarchical logistic regression estimated adjusted associations between community features and bystander CPR. Of 1,592 subjects, 1,465 met inclusion criteria. Geospatial analysis revealed significant clustering of OHCA in more populated/urban areas. Conversely, bystander CPR was less likely in these areas (99% confidence) and more likely in suburban and rural areas (99% confidence). Adjusting for clinical, demographic, and socioeconomic covariates, bystander CPR was associated with public location (odds ratio [OR] = 1.19; 95% confidence interval [CI] = 1.03-1.39), initially shockable rhythms (OR = 1.48; 95% CI = 1.12-1.96), and those in urban neighborhoods (OR = 0.54; 95% CI = 0.38-0.77). Out-of-hospital cardiac arrest and bystander CPR are geographically clustered in Kent County, Michigan, but bystander CPR is inversely associated with urban designation. These results offer new insight into bystander CPR patterns in mixed urban and rural

X-irradiation of human bronchial cancer cells causes the bystander effects in normal bronchial cells in vitro.

PubMed

Konopacka, M; Rogoliński, J

2010-01-01

Using X radiation commonly used in radiotherapy of cancers we investigated bystander interactions between human cells: irradiated A549 bronchial carcinoma human cells and non irradiated BEAS-2B normal bronchial epithelial cells. Non irradiated cells were incubated in medium transferred from irradiated A549 cells (ICM-irradiation conditioned medium) for 48h and next the chromosomal damage and apoptosis were estimated. Conditioned medium collected from irradiated cancer cells induced in non irradiated cells of the same line as well as in BEAS-2B normal cells genetic changes such as micronuclei, chromatid and chromosomal breaks and condensation of chromatin characteristic for processes of apoptosis. Addition of only 1% of conditioned medium to fresh medium was sufficient to induction of bystander response to normal bronchial cells. The presented results in this study could have implications for human radiation risk and in evaluating the secondary effects of radiotherapy.

It's Your Place: Development and Evaluation of an Evidence-Based Bystander Intervention Campaign.

PubMed

Sundstrom, Beth; Ferrara, Merissa; DeMaria, Andrea L; Gabel, Colby; Booth, Kathleen; Cabot, Jeri

2017-06-28

Preventing sexual assault on college campuses is a national priority. Bystander intervention offers a promising approach to change social norms and prevent sexual misconduct. This study presents the implementation and evaluation of a theory-based campaign to promote active bystander intervention. The theory of planned behavior (TPB) served as a conceptual framework throughout campaign development and evaluation. Formative research published elsewhere was used to develop campaign strategies, communication channels, and messages, including "It is your place to prevent sexual assault: You're not ruining a good time." The It's Your Place multi-media campaign fosters a culture of bystander intervention through peer-to-peer facilitation and training, as well as traditional and new media platforms. A cross-sectional post-test only web-based survey was designed to evaluate the campaign and test the TPB's ability to accurately predict intention to intervene. Survey data were collected from 1,505 currently enrolled students. The TPB model predicted intention to intervene. There was a significant effect of campaign exposure on attitude, subjective norms, and perceived behavioral intention. This theory-based communication campaign offers implications for promoting active bystander intervention and reducing sexual assault.

The survival benefit of bystander cardiopulmonary resuscitation in a paramedic served metropolitan area.

PubMed Central

Guzy, P M; Pearce, M L; Greenfield, S

1983-01-01

We investigated the survival benefit bystander cardiopulmonary resuscitation (CPR) for out-of-hospital emergencies in a paramedic served area of metropolitan Los Angeles. Clinical information for all events occurring between January 1 and December 31, 1978 was obtained from paramedic report forms and hospital medical records. Bystander CPR was performed for 93 cases and, of these, 20 (22 per cent) survived to hospital discharge, as compared to 7 (5 per cent) of the 150 patients not receiving bystander CPR (p less than 0.001). Twelve (27 per cent) of the 45 patients in ventricular fibrillation (VF) who had bystander CPR survived, as compared to 4 (6 per cent) of 70 VF patients without bystander CPR (p less than 0.01). We conclude that bystander CPR, initiated prior to arrival of paramedics, produced a fourfold improvement in survival. Overall there was a 10 per cent survival rate at hospital discharge. Survival rates reported from Seattle may not necessarily be generalized to larger cities. PMID:6859360

Adolescent bystanders' perspectives of aggression in the online versus school environments.

PubMed

Patterson, Lisa J; Allan, Alfred; Cross, Donna

2016-06-01

Researchers' understanding of bystanders' perspectives in the cyber-environment fails to take young people's perceptions into account and remains imperfect. Interventions encouraging adolescents to help targets of cyber-aggression are therefore typically based upon traditional school-based aggression research. Twenty-four in-depth interviews with Australian 13-16 year-olds revealed two themes that reflect how young bystanders perceive differences between aggression online and at school. The physical presence theme suggests that young bystanders struggle to determine online intentions in the absence of body language, leading to hesitancy in reactions and furthermore make it easier for them to ignore online transgressions and avoid becoming involved. The authority theme indicates young bystanders perceive that, compared to the school environment, the online environment lacks clearly established rules, authority figures and formal reporting mechanisms. These differences indicate that unique strategies should be developed to encourage young bystanders to intervene in cyber-aggression situations. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Sci—Fri PM: Topics — 04: What if bystander effects influence cell kill within a target volume? Potential consequences of dose heterogeneity on TCP and EUD on intermediate risk prostate patients

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

Balderson, M.J.; Kirkby, C.; Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta

In vitro evidence has suggested that radiation induced bystander effects may enhance non-local cell killing which may influence radiotherapy treatment planning paradigms. This work applies a bystander effect model, which has been derived from published in vitro data, to calculate equivalent uniform dose (EUD) and tumour control probability (TCP) and compare them with predictions from standard linear quadratic (LQ) models that assume a response due only to local absorbed dose. Comparisons between the models were made under increasing dose heterogeneity scenarios. Dose throughout the CTV was modeled with normal distributions, where the degree of heterogeneity was then dictated by changingmore » the standard deviation (SD). The broad assumptions applied in the bystander effect model are intended to place an upper limit on the extent of the results in a clinical context. The bystander model suggests a moderate degree of dose heterogeneity yields as good or better outcome compared to a uniform dose in terms of EUD and TCP. Intermediate risk prostate prescriptions of 78 Gy over 39 fractions had maximum EUD and TCP values at SD of around 5Gy. The plots only dropped below the uniform dose values for SD ∼ 10 Gy, almost 13% of the prescribed dose. The bystander model demonstrates the potential to deviate from the common local LQ model predictions as dose heterogeneity through a prostate CTV is varies. The results suggest the potential for allowing some degree of dose heterogeneity within a CTV, although further investigations of the assumptions of the bystander model are warranted.« less

A composite microdose Adaptive Response (AR) and Bystander Effect (BE) model-application to low LET and high LET AR and BE data.

PubMed

Leonard, Bobby E

2008-08-01

It has been suggested that Adaptive Response (AR) may reduce risk of adverse health effects due to ionizing radiation. But very low dose Bystander Effects (BE) may impose dominant deleterious human risks. These conflicting behaviors have stimulated controversy regarding the Linear No-Threshold human risk model. A dose and dose rate-dependent microdose model, to examine AR behavior, was developed in prior work. In the prior work a number of in vitro and in vivo dose response data were examined with the model. Recent new data show AR behavior with some evidence of very low dose BE. The purpose of this work is to supplement the microdose model to encompass the Brenner and colleagues BaD (Bystander and Direct Damage) model and apply this composite model to obtain new knowledge regarding AR and BE and illustrate the use of the model to plan radio-biology experiments. The biophysical composite AR and BE Microdose Model quantifies the accumulation of hits (Poisson distributed, microdose specific energy depositions) to cell nucleus volumes. This new composite AR and BE model provides predictions of dose response at very low dose BE levels, higher dose AR levels and even higher dose Direct (linear-quadratic) Damage radiation levels. We find good fits of the model to both BE data from the Columbia University microbeam facility and combined AR and BE data for low Linear Energy Transfer (LET) and high LET data. A Bystander Factor of about 27,000 and an AR protection factor of 0.61 are obtained for the low LET in vivo mouse spleen exposures. A Bystander Factor of 317 and an AR protection factor of 0.53 are obtained for high LET radon alpha particles in human lymphocytes. In both cases the AR is activated at most by one or two radiation induced charged particle traversals through the cell nucleus. The results of the model analysis is consistent with a premise that both Bystander damage and Adaptive Response radioprotection can occur in the same cell type, derived from the same

Multi-College Bystander Intervention Evaluation for Violence Prevention.

PubMed

Coker, Ann L; Bush, Heather M; Fisher, Bonnie S; Swan, Suzanne C; Williams, Corrine M; Clear, Emily R; DeGue, Sarah

2016-03-01

The 2013 Campus Sexual Violence Elimination Act requires U.S. colleges to provide bystander-based training to reduce sexual violence, but little is known about the efficacy of such programs for preventing violent behavior. This study provides the first multiyear evaluation of a bystander intervention's campus-level impact on reducing interpersonal violence victimization and perpetration behavior on college campuses. First-year students attending three similarly sized public university campuses were randomly selected and invited to complete online surveys in the spring terms of 2010-2013. On one campus, the Green Dot bystander intervention was implemented in 2008 (Intervention, n=2,979) and two comparison campuses had no bystander programming at baseline (Comparison, n=4,132). Data analyses conducted in 2014-2015 compared violence rates by condition over the four survey periods. Multivariable logistic regression was used to estimate violence risk on Intervention relative to Comparison campuses, adjusting for demographic factors and time (2010-2013). Interpersonal violence victimization rates (measured in the past academic year) were 17% lower among students attending the Intervention (46.4%) relative to Comparison (55.7%) campuses (adjusted rate ratio=0.83; 95% CI=0.79, 0.88); a similar pattern held for interpersonal violence perpetration (25.5% in Intervention; 32.2% in Comparison; adjusted rate ratio=0.79; 95% CI=0.71, 0.86). Violence rates were lower on Intervention versus Comparison campuses for unwanted sexual victimization, sexual harassment, stalking, and psychological dating violence victimization and perpetration (p<0.01). Green Dot may be an efficacious intervention to reduce violence at the community level and meet Campus Sexual Violence Elimination Act bystander training requirements. Copyright © 2016 American Journal of Preventive Medicine. All rights reserved.

Multi–College Bystander Intervention Evaluationon for Violence Prevention

PubMed Central

Coker, Ann L.; Bush, Heather M.; Fisher, Bonnie S.; Swan, Suzanne C.; Williams, Corrine M.; Clear, Emily R.; DeGue, Sarah

2015-01-01

Introduction The 2013 Campus Sexual Violence Elimination Act requires U.S. colleges to provide bystander-based training to reduce sexual violence, but little is known about the efficacy of such programs for preventing violent behavior. This study provides the first multiyear evaluation of a bystander intervention’s campus-level impact on reducing interpersonal violence victimization and perpetration behavior on college campuses. Methods First-year students attending three similarly sized public university campuses were randomly selected and invited to complete online surveys in the spring terms of 2010–2013. On one campus, the Green Dot bystander intervention had been implemented since 2008 (Intervention, n=2,979) and two Comparison campuses had no bystander programming at baseline (Comparison, n=4,132). Data analyses conducted in 2014–2015 compared violence rates by condition over the four survey periods. Multivariable logistic regression was used to estimate violence risk on Intervention relative to Comparison campuses adjusting for demographic factors and time (2010–2013). Results Interpersonal violence victimization rates (measured in the past academic year) were 17% lower among students attending the Intervention (46.4%) relative to Comparison (55.7%) campuses (adjusted rate ratio, 0.83; 95% CI=0.79, 0.88); a similar pattern held for interpersonal violence perpetration (25.5% in Intervention; 32.2% in Comparison; adjusted rate ratio, 0.79; 95% CI=0.71, 0.86). Violence rates were lower on Intervention versus Comparison campuses for unwanted sexual victimization, sexual harassment, stalking, and psychological dating violence victimization and perpetration (p<0.01). Conclusions Green Dot may be an efficacious intervention to reduce violence at the community-level and meet Campus Sexual Violence Elimination Act bystander training requirements. PMID:26541099

Measuring Bystander Attitudes and Behavior to Prevent Sexual Violence

ERIC Educational Resources Information Center

McMahon, Sarah; Allen, Christopher T.; Postmus, Judy L.; McMahon, Sheila M.; Peterson, N. Andrew; Lowe Hoffman, Melanie

2014-01-01

Objective: The purpose of this study is to further investigate the factor structure and strength of the Bystander Attitude Scale-Revised and Bystander Behavior Scale-Revised (BAS-R and BBS-R). Participants: First-year students (N = 4,054) at a large public university in the Northeast completed a survey in 2010 as part of a larger longitudinal…

Engaging Upstanders: Class-Wide Approach to Promoting Positive Bystander Behavior

ERIC Educational Resources Information Center

Wood, Laura; Smith, Jennifer; Varjas, Kris; Meyers, Joel

2016-01-01

Positive and supportive bystander behaviors have been associated with decreases in the frequency and negative impact of bullying. This article addresses the design, implementation, evaluation, and continuation of a classroom-based intervention that promotes positive bystander behaviors. The Engaging Upstanders curriculum was piloted with two…

Implications for Sexual Assault Prevention: College Students as Prosocial Bystanders

ERIC Educational Resources Information Center

Exner, Deinera; Cummings, Nina

2011-01-01

Prosocial bystander interventions are promising approaches to sexual assault prevention on college campuses. Objective: To assess bystander attitudes among undergraduate students at a northeastern university. Participants: A convenience sample of 188 students from 4 undergraduate classes was surveyed during regularly scheduled class sessions.…

TakeCARE, a Video Bystander Program to Help Prevent Sexual Violence on College Campuses: Results of Two Randomized, Controlled Trials

PubMed Central

Jouriles, Ernest N.; McDonald, Renee; Rosenfield, David; Levy, Nicole; Sargent, Kelli; Caiozzo, Christina; Grych, John H.

2015-01-01

Objective The present research reports on two randomized controlled trials evaluating TakeCARE, a video bystander program designed to help prevent sexual violence on college campuses. Method In Study 1, students were recruited from psychology courses at two universities. In Study 2, first-year students were recruited from a required course at one university. In both studies, students were randomly assigned to view one of two videos: TakeCARE or a control video on study skills. Just before viewing the videos, students completed measures of bystander behavior toward friends and ratings of self-efficacy for performing such behaviors. The efficacy measure was administered again after the video, and both the bystander behavior measure and the efficacy measure were administered at either one (Study 1) or two (Study 2) months later. Results In both studies, students who viewed TakeCARE, compared to students who viewed the control video, reported engaging in more bystander behavior toward friends and greater feelings of efficacy for performing such behavior. In Study 1, feelings of efficacy mediated effects of TakeCARE on bystander behavior; this result did not emerge in Study 2. Conclusions This research demonstrates that TakeCARE, a video bystander program, can positively influence bystander behavior toward friends. Given its potential to be easily distributed to an entire campus community, TakeCARE might be an effective addition to campus efforts to prevent sexual violence. PMID:27867694

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

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

First aid: level of knowledge of relatives and bystanders in emergency situations.

PubMed

Tomruk, Onder; Soysal, Suna; Gunay, Turkan; Cimrin, Arif H

2007-01-01

Bystanders who are able to provide immediate first aid to patients who require emergency care can make a big difference in the outcome. Thus, first-aid training should be made available to as many people as possible. The aims of this study were to assess the level of first-aid knowledge among bystanders in emergency situations and to identify factors that affected this level of knowledge. At Dokuz Eylul University Emergency Service between February 1 and February 15, 2002, 318 bystanders were given a questionnaire. The first part of the questionnaire was concerned with demographic characteristics and factors that would affect first-aid knowledge level. The second part consisted of 16 multiple choice questions about first aid. Bystanders answered an average of 7.16+/-3.14 questions correctly. Bystanders who had graduated from a university, were health care personnel, had taken a first-aid course, had a first-aid certificate, or had a driver's license were considered to be more successful.

Effect and accuracy of emergency dispatch telephone guidance to bystanders in trauma: post-hoc analysis of a prospective observational study.

PubMed

Bakke, Håkon Kvåle; Steinvik, Tine; Ruud, Håkon; Wisborg, Torben

2017-03-07

Emergency medical communication centres (EMCCs) dispatch and allocate ambulance resources, and provide first-aid guidance to on-scene bystanders. We aimed to 1) evaluate whether dispatcher guidance improved bystander first aid in trauma, and 2) to evaluate whether dispatchers and on-scene emergency medical services (EMS) crews identified the same first aid measures as indicated. For 18 months, the crew on the first EMS crew responding to trauma calls used a standard form to assess bystander first aid. Audio recordings of the corresponding telephone calls from bystanders to the EMCC were reviewed. A total of 311 trauma calls were included. The on-scene EMS crew identified needs for the following first-aid measures: free airway in 26 patients, CPR in 6 patients, and hypothermia prevention in 179 patients. EMCC dispatchers advised these measures, respectively, in 16 (62%), 5 (83%), and 54 (30%) of these cases. Dispatcher guidance was not correlated with correctly performed bystander first aid. For potentially life saving first aid measures, all (20/20) callers who received dispatcher guidance attempted first aid, while only some few (4/22) of the callers who did not receive dispatcher guidance did not attempt first aid. Overall, the EMCC dispatchers had low sensitivity and specificity for correctly identifying trauma patients requiring first-aid measures. Dispatcher guidance did not significantly influence whether on-scene bystander first aid was performed correctly or attempted in this study setting, with a remarkably high willingness to perform first-aid. However, the findings for potentially lifesaving measures suggests that there may be differences that this study was unable to detect. This study found a high rate of first-aid willingness and performance, even without dispatcher prompting, and a low precision in dispatcher advice. This underlines the need for further knowledge about how to increase EMCC dispatchers' possibility to identify trauma patients in need

Rape Myth Beliefs and Bystander Attitudes among Incoming College Students

ERIC Educational Resources Information Center

McMahon, Sarah

2010-01-01

Objective: The bystander approach to rape prevention is gaining popularity on college campuses, although research is limited. This study explored bystander attitudes and their relationship with rape myths in a sample of college students. Participants: Surveys from 2,338 incoming undergraduate students at a large, northeastern university were…

Predicting bystander intervention among middle school students.

PubMed

Menolascino, Nicole; Jenkins, Lyndsay N

2018-06-01

Bullying is a prevalent issue in schools, and the importance of involving bystanders in bullying prevention has been recognized; however, there are few studies that examine personal characteristics that relate to the five steps of Latané and Darley's (1970) Bystander Intervention Model (notice the event, interpret as an emergency, accept responsibility, know what to do, and act). This study examined cognitive and affective empathy and perceived popularity and their relation to each of the five steps of the Bystander Intervention Model in Bullying (Nickerson, Aloe, Livingston, & Feeley, 2014), as well as explored if gender changed those relations. With a sample of 346 sixth to eighth grade students, we found a negative relation between perceived popularity and noticing bullying events. For boys, higher affective empathy was associated with a greater likelihood of interpreting bullying as an emergency and accepting responsibility for intervening, but for girls, their perception of bullying as an emergency and accepting responsibility was stable regardless of their level of affective empathy. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Association of initial rhythm with neurologically favorable survival in non-shockable out-of-hospital cardiac arrest without a bystander witness or bystander cardiopulmonary resuscitation.

PubMed

Fukuda, Tatsuma; Ohashi-Fukuda, Naoko; Matsubara, Takehiro; Doi, Kent; Kitsuta, Yoichi; Nakajima, Susumu; Yahagi, Naoki

2016-05-01

Out-of-hospital cardiac arrest (OHCA) has a predominantly non-shockable rhythm. Non-shockable rhythm, and the absence of a bystander witness or bystander cardiopulmonary resuscitation (CPR) are associated with poor outcomes. However, the association between the type of non-shockable rhythm and outcomes is not well known. To examine the association between the initial rhythm and neurologically favorable outcomes after non-shockable OHCA without a bystander witness or bystander CPR. In a nationwide, population-based, cohort study, we analyzed 213,984 adult OHCA patients with a non-shockable rhythm who had neither a bystander witness nor bystander CPR. They were identified through the Japanese national OHCA registry data from January 1, 2005 to December 31, 2010. The primary outcome was neurologically favorable survival. Among 213,984 patients, the initial rhythm was Pulseless Electrical Activity (PEA) in 31,179 patients (14.6%) and Asystole in 182,805 patients (85.4%). The neurological outcome was more favorable in PEA than in Asystole (1.4% vs. 0.2%, p<0.0001). After adjusting for age, sex, etiology of arrest, epinephrine administration, advanced airway management, time from call to contact with patient, and calendar year, PEA was associated with an increased neurologically favorable survival rate (odds ratio 7.86; 95% confidence interval 6.81-9.07). In subgroup analysis stratified by age group (18-64, 65-84, or ≥85years), the neurologically favorable survival rate was ≥1% in PEA, even for patients aged ≥85years, but <1% in Asystole among all age groups. PEA and Asystole should not be considered to be identical to non-shockable rhythm, but rather should be clearly distinguished from each other from the perspective of quantitative medical futility. Copyright © 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Chronic bystander infections and immunity to unrelated antigens

PubMed Central

Stelekati, Erietta; Wherry, E. John

2012-01-01

Chronic infections with persistent pathogens such as helminths, mycobacteria, Plasmodium and hepatitis viruses affect more than a third of the human population and are associated with increased susceptibility to other pathogens as well as reduced vaccine efficacy. Although these observations suggest an impact of chronic infections in modulating immunity to unrelated antigens, little is known regarding the underlying mechanisms. Here, we summarize evidence of the most prevalent infections affecting immunity to unrelated pathogens and vaccines, and discuss potential mechanisms of how different bystander chronic infections might impact immune responses. We suggest that bystander chronic infections affect different stages of host responses and may impact transmission of other pathogens, recognition and innate immune responses, priming and differentiation of adaptive effector responses, as well as the development and maintenance of immunological memory. Further understanding of the immunological effects of co-infection should provide opportunities to enhance vaccine efficacy and control infectious diseases. PMID:23084915

No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblasts after alpha particle irradiation

NASA Astrophysics Data System (ADS)

Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K.

2013-02-01

A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G2 phase premature chromosome condensation (G2-PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. mFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblast after alpha particle irradiation.

PubMed

Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K

2013-02-01

A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G 2 phase premature chromosome condensation (G 2 -PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. MFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

Non-targeted and delayed effects of exposure to ionizing radiation: I. Radiation-induced genomic instability and bystander effects in vitro

NASA Technical Reports Server (NTRS)

Morgan, William F.

2003-01-01

A long-standing dogma in the radiation sciences is that energy from radiation must be deposited in the cell nucleus to elicit a biological effect. A number of non-targeted, delayed effects of ionizing radiation have been described that challenge this dogma and pose new challenges to evaluating potential hazards associated with radiation exposure. These effects include induced genomic instability and non-targeted bystander effects. The in vitro evidence for non-targeted effects in radiation biology will be reviewed, but the question as to how one extrapolates from these in vitro observations to the risk of radiation-induced adverse health effects such as cancer remains open.

Designing, implementing, and evaluating a media campaign illustrating the bystander role.

PubMed

Potter, Sharyn J; Stapleton, Jane G; Moynihan, Mary M

2008-01-01

Recent research found that training men and women to understand the role of bystanders in situations where violence against women (VAW) is occurring may reduce the incidence of VAW (Moynihan & Banyard, 2004). Therefore a public awareness campaign to increase understanding of the prosocial role of bystanders in reducing VAW was developed and implemented. The current article discusses the role of media campaigns in addressing public health issues and describes the initial development, implementation, and evaluation of a media campaign focused on the bystander role in reducing the incidence of VAW. Conclusions and future directions of this exploratory project are discussed.

School personnel social support and nonsupport for bystanders of bullying: Exploring student perspectives.

PubMed

Wood, Laura; Smith, Jennifer; Varjas, Kris; Meyers, Joel

2017-04-01

Defending behaviors by bystanders in bullying situations have been associated with decreases in the frequency and negative effects of bullying incidents. The current study utilized qualitative methodology to investigate the role of perceived school personnel support and nonsupport in students' decisions to display defending behaviors. Forty-six semi-structured interviews were conducted with upper-elementary (n=26) and middle school (n=20) students in the southeastern United States. Qualitative data were analyzed using constant comparison and a recursive inductive-deductive approach. The findings resulted in the conceptualization of a combined social support-nonsupport framework that provides details about the source, description, evaluation, and perceived effects of different types of support and nonsupport bystanders receive from school personnel. Unique contributions to the literature included expanding the sources of support and nonsupport to consider school personnel other than teachers, providing descriptions and evaluations of support and nonsupport specific to bystanders, and demonstrating an overlap between various types of support and nonsupport reiterating the need to consider both supports and nonsupports concurrently. Implications for research and practice are discussed. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Being a Positive Bystander: Male Antiviolence Allies’ Experiences of “Stepping Up”

PubMed Central

Casey, Erin A.; Ohler, Kristin

2014-01-01

As bystander approaches become increasingly prevalent elements of sexual and domestic violence prevention efforts, it is necessary to better understand the factors that support or impede individuals in taking positive action in the face of aggressive or disrespectful behavior from others. This study presents descriptive findings about the bystander experiences of 27 men who recently became involved in antiviolence against women work. More specifically, we describe the consistency with which respondents actively intervene in the speech or behavior of others, the strategies they use, and the factors they weigh as they deliberate taking action. Respondents report a complex and interrelated set of individual and contextual influences on their choices within bystander opportunities, which hold implications for both violence-specific models of bystander behavior and for prevention intervention development. PMID:21859757

Role of the MAPK pathway in the observed bystander effect in lymphocytes co-cultured with macrophages irradiated with γ-rays or carbon ions.

PubMed

Dong, Chen; He, Mingyuan; Ren, Ruiping; Xie, Yuexia; Yuan, Dexiao; Dang, Bingrong; Li, Wenjian; Shao, Chunlin

2015-04-15

The radiation-induced bystander effect (RIBE) has potential implications in cancer risks from space particle radiation; however, the mechanisms underlying RIBE are unclear. The role of the MAPK pathway in the RIBEs of different linear energy transfer (LET) was investigated. Human macrophage U937 cells were irradiated with γ-rays or carbon ions and then co-cultured with nonirradiated HMy2.CIR (HMy) lymphocytes for different periods. The activation of MAPK proteins and the generation of intracellular nitric oxide (NO) and reactive oxygen species (ROS) in the irradiated U937 cells were measured. Micronuclei (MN) formation in the HMy cells was applied to evaluate the bystander damage. Some U937 cells were pretreated with different MAPK inhibitors before irradiation. Additional MN formation was induced in the HMy cells after co-culturing with irradiated U937 cells, and the yield of this bystander MN formation was dependent on the co-culture period with γ-ray irradiation but remained high after 1h of co-culture with carbon irradiation. Further investigations disclosed that the time response of the RIBEs had a relationship with LET, where ERK played a different role from JNK and p38 in regulating RIBEs by regulating the generation of the bystander signaling factors NO and ROS. The finding that the RIBE of high-LET radiation could persist for a much longer period than that of γ-rays implies that particle radiation during space flight could have a high risk of long-term harmful effects. An appropriate intervention targeting the MAPK pathway may have significant implications in reducing this risk. Copyright © 2015 Elsevier Inc. All rights reserved.

Bystander Attitudes to Prevent Sexual Assault: A Study of College Students in the United States, Japan, India, Vietnam, and China.

PubMed

Kamimura, Akiko; Trinh, Ha Ngoc; Nguyen, Hanh; Yamawaki, Niwako; Bhattacharya, Haimanti; Mo, Wenjing; Birkholz, Ryan; Makomenaw, Angie; Olson, Lenora M

2016-01-01

College women are at a high risk of sexual assault. Although programs that aim to change bystander behaviors have been shown to be potentially effective in preventing sexual assault on campuses in the United States, little is known about bystander behaviors outside of the United States. The purpose of this study was to explore and compare factors affecting bystander behaviors regarding sexual assault intervention and prevention among undergraduate students in the United States, Japan, India, Vietnam, and China. A total of 1,136 students participated in a self-reported survey. Results demonstrate substantial variations across countries. Bystander behaviors are associated with multilevel factors, including gender, knowledge of individuals who have experienced a sexual assault, and knowledge about campus or community organizations.

Why Do Bystanders of Bullying Help or Not? A Multidimensional Model

ERIC Educational Resources Information Center

Pozzoli, Tiziana; Gini, Gianluca

2013-01-01

The authors employed Latane and Darley's model about bystanders' behavior to explain children's active defending and passive bystanding behavior in school bullying. The three central steps of the model were operationalized by measuring provictim attitudes, personal responsibility for intervention, and coping strategies. Moreover, the role of…

Quantifying the bystander-effect of 2.5G mobile telephones on the speech perception of digital hearing aid users.

PubMed

Vlastarakos, P V; Nikolopoulos, T P; Manolopoulos, L; Stamou, A; Halkiotis, K K; Ferekidis, E; Georgiou, E

2012-01-01

To quantify the bystander-effect of 2.5G mobile telephones (2.5G-MTs) on the speech perception of digital hearing-aid (dHA) users. Differences in the susceptibility of behind-the-ear (BTE) compared to in-to-the-ear (ITE) dHAs were also assessed. Prospective-comparative study conducted at a tertiary referral centre (ENT Department) and a HA-fitting laboratory. Key-word recognition scores from open-sentence lists were calculated. Power-analysis determined that a minimum of 60 subjects with SNHL (30 in each group), using either BTE or ITE dHAs, were required for reliable study outcomes. Sixty-four adults were tested with a functioning 2.5G-MT at almost physical contact with their ear; thirty subjects used BTE and 34 ITE dHAs. Aided word recognition score differences between studied groups and within each group, while a 2.5G-MT was activated. Cut-off inclusion criterion regarding baseline aided word recognition score was 75%. Baseline aided word recognition scores for ITE dHAs were better compared to BTE ones (p < 0.01). Following the 2.5G-MT activation, this difference disappeared. No statistically significant difference in word recognition was observed between the examined groups, or within the BTE group, from the bystander-effect of the 2.5G-MT. ITE dHAs proved more susceptible to electromagnetic interference (p < 0.05). The bystander-effect of 2.5G-MTs on the speech perception of dHA users is either minimal, or not significant. The observed compatibility has a positive impact on the lives of millions of people worldwide. The long-standing theory of more interference in BTE compared to ITE HAs is not confirmed by the results of the present study. EBM level of evidence: 2c.

Activation of caspase-3 noninvolved in the bystander effect of the herpes simplex virus thymidine kinase gene/ganciclovir (HSV-tk/GCV) system.

PubMed

Zhang, Zhihong; Lin, Juqiang; Chu, Jun; Ma, Yan; Zeng, Shaoqun; Luo, Qingming

2008-01-01

Use of the herpes simplex virus thymidine kinase gene/ganciclovir (HSV-tk/GCV) system is one of the promising approaches in the rapidly growing area of gene therapy. The "bystander effect," a phenomenon in which HSV-tk+ cells exposed to GCV are toxic to adjacent HSV-tk- cells, was reported to play an important role in suicide gene therapy. However, the mechanism by which HSV-tk/GCV induces the bystander effect is poorly understood. We monitored the activation of caspase-3 in living cells induced by the HSV-tk/GCV system using a genetically encoded fluorescence resonance energy transfer (FRET) probe CD3, , a caspase-3 recognition site fused with a cyan fluorescent protien (CFP) and a red fluorescent protein (DsRed) which we reported and named in a previous paper. Fluorescence protein (FP)-based multicolor cellular labeling, combined with the multichannel fluorescence imaging and FRET imaging techniques, provides a novel and improved approach to directly determine whether the activation of caspase-3 involved in the HSV-tk/GCV system induces cell apoptosis in tk gene-expressing cells and their neighboring cells. FRET ratio images of CD3, and fluorescence images of the fusion protein of thymidine kinase linked with green fluorescent protein (TK-GFP), indicated that HSV-tk/GCV system-induced apoptosis in human adenoid cystic carcinoma (ACC-M) cells was via a caspase-3 pathway, and the activation of caspase-3 was not involved in the bystander effect of HSV-tk/GCV system.

Mechanisms and biological importance of photon-induced bystander responses: do they have an impact on low-dose radiation responses

PubMed Central

Tomita, Masanori; Maeda, Munetoshi

2015-01-01

Abstract Elucidating the biological effect of low linear energy transfer (LET), low-dose and/or low-dose-rate ionizing radiation is essential in ensuring radiation safety. Over the past two decades, non-targeted effects, which are not only a direct consequence of radiation-induced initial lesions produced in cellular DNA but also of intra- and inter-cellular communications involving both targeted and non-targeted cells, have been reported and are currently defining a new paradigm in radiation biology. These effects include radiation-induced adaptive response, low-dose hypersensitivity, genomic instability, and radiation-induced bystander response (RIBR). RIBR is generally defined as a cellular response that is induced in non-irradiated cells that receive bystander signals from directly irradiated cells. RIBR could thus play an important biological role in low-dose irradiation conditions. However, this suggestion was mainly based on findings obtained using high-LET charged-particle radiations. The human population (especially the Japanese, who are exposed to lower doses of radon than the world average) is more frequently exposed to low-LET photons (X-rays or γ-rays) than to high-LET charged-particle radiation on a daily basis. There are currently a growing number of reports describing a distinguishing feature between photon-induced bystander response and high-LET RIBR. In particular, photon-induced bystander response is strongly influenced by irradiation dose, the irradiated region of the targeted cells, and p53 status. The present review focuses on the photon-induced bystander response, and discusses its impact on the low-dose radiation effect. PMID:25361549

Promoting Prosocial Behaviors to Prevent Dating Violence among College Students: Evaluation of a Bystander Intervention

ERIC Educational Resources Information Center

Borsky, Amanda E.

2014-01-01

The objective of this dissertation was to evaluate a bystander behavior program at the Jefferson College of Health Sciences (JCHS) in Roanoke, Virginia. Specifically, this dissertation examined the: (1) preliminary measurement properties of a newly developed bystander behavior intention scale; (2) impact of the bystander intervention at JCHS; and…

A Randomized Controlled Trial of a Multi-Dose Bystander Intervention Program Using Peer Education Theater

ERIC Educational Resources Information Center

McMahon, Sarah; Winter, Samantha C.; Palmer, Jane E.; Postmus, Judy L.; Peterson, N. Andrew; Zucker, Sharon; Koenick, RuthAnne

2015-01-01

This article reports findings from a longitudinal, experimental evaluation of a peer education theater program, Students Challenging Realities and Educating Against Myths (SCREAM) Theater. This study examines the impact of SCREAM Theater on a range of bystander-related outcomes (i.e. bystander intentions, bystander efficacy, perception of friend…

Are Chinese Students Willing to Learn and Perform Bystander Cardiopulmonary Resuscitation?

PubMed

Huang, Qiao; Hu, Cuihuan; Mao, Jing

2016-12-01

Immediate cardiopulmonary resuscitation (CPR) can improve survival rate from cardiac arrest and students are potentially important bystander CPR providers. Our aim was to investigate the willingness among Chinese students to learn and perform bystander CPR. Questionnaires were distributed to 1407 students. The survey investigated the willingness to learn and perform bystander CPR and the barriers to performing CPR on family members and strangers, assuming that students had mastered CPR. Only 14.6% of respondents reported having ever attended CPR training classes, however, 88.3% expressed their willingness to learn. The main characteristics of the students who were willing to learn were the following: they considered the development of the local emergency system excellent (odds ratio [OR] = 3.15); cardiovascular diseases were present within their family (OR = 2.74); and they had previously heard about CPR (OR = 2.43). Almost all respondents (94.6%) reported that they would conduct bystander CPR on family members, while only 59.7% of respondents would do it for strangers. A lack of confidence was the principal barrier to doing CPR for family members (78.4%) and the leading barrier to stranger CPR was the fear of legal liability if their lifesaving attempts failed (90.8%). The complicated process of performing CPR was also a major barrier in both scenarios. When there is a great desire to learn CPR, the rate and effect of training can be significantly improved by providing students with regular CPR training, especially compression-only CPR training. Training classes should focus on enhancing the participants' confidence. In addition, legislation by the government is needed to protect the rescuers. Copyright © 2016 Elsevier Inc. All rights reserved.

Bystander Intervention Among College Men: The Role of Alcohol and Correlates of Sexual Aggression.

PubMed

Orchowski, Lindsay M; Berkowitz, Alan; Boggis, Jesse; Oesterle, Daniel

2016-10-01

Current efforts to reduce sexual violence in college campuses underscore the role of engaging men in prosocial bystander behavior. The current study implemented an online survey to explore associations between engaging in heavy drinking and attitudes toward bystander intervention among a sample of college men (N = 242). Correlates of sexual aggression were also explored as mediators of the hypothesized relationship between engaging in heavy drinking and attitudes toward bystander intervention. Data indicated that men who engaged in two or more episodes of heavy drinking over the past month reported lower prosocial bystander attitudes compared with men who did not engage in such behavior. The association between engaging in heavy drinking and lower prosocial bystander attitudes was mediated by men's perception of their peers' approval for sexual aggression, their own comfort with sexism, and engagement in coercive sexual behavior. Implications for sexual assault prevention are discussed. © The Author(s) 2015.

The release of bystander factor(s) from tissue explant cultures of rainbow trout (Onchorhynchus mykiss) after exposure to gamma radiation.

PubMed

O'Dowd, Colm; Mothersill, Carmel E; Cairns, Michael T; Austin, Brian; McClean, Brendan; Lyng, Fiona M; Murphy, James E J

2006-10-01

The bystander response has been documented in cell lines and cell cultures derived from aquatic species over the past several years. However, little work has been undertaken to identify a similar bystander response in tissue explant cultures from fish. In this study, indirect effects of ionizing gamma radiation on tissue explant cultures of fish were investigated. Tissue explants in culture were exposed to 0.5 Gy and 5 Gy gamma radiation from a 60Co teletherapy unit. A bystander response in Epithelioma papulosum cyprini (EPC) cells exposed to gamma-irradiated tissue conditioned medium from rainbow trout explants was investigated, and the effects on cell survival were quantified by the clonogenic survival assay. Dichlorofluorescein and rhodamine 123 fluorescent dyes were used to identify alterations in reactive oxygen species (ROS) and mitochondrial membrane potential (MMP), respectively. Results indicate a different response for the three tissue types investigated. Clonogenic assay results vary from a decrease in cell survival (gill) to no effect (skin) to a stimulatory effect (spleen). Results from fluorescence assays of ROS and MMP show similarities to clonogenic assay results. This study identifies a useful model for further studies relating to the bystander effect in aquatic organisms in vivo and ex vivo.

Genetic changes in progeny of bystander human fibroblasts after microbeam irradiation with X-rays, protons or carbon ions: the relevance to cancer risk.

PubMed

Autsavapromporn, Narongchai; Plante, Ianik; Liu, Cuihua; Konishi, Teruaki; Usami, Noriko; Funayama, Tomoo; Azzam, Edouard I; Murakami, Takeshi; Suzuki, Masao

2015-01-01

Radiation-induced bystander effects have important implications in radiotherapy. Their persistence in normal cells may contribute to risk of health hazards, including cancer. This study investigates the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of harmful effects in progeny of bystander cells. Confluent human skin fibroblasts were exposed to microbeam radiations with different linear energy transfer (LET) at mean absorbed doses of 0.4 Gy by which 0.036-0.4% of the cells were directly targeted by radiation. Following 20 population doublings, the cells were harvested and assayed for micronucleus formation, gene mutation and protein oxidation. Our results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET. The progeny of bystander cells exposed to X-rays (LET ∼6 keV/μm) or protons (LET ∼11 keV/μm) showed persistent oxidative stress, which correlated with increased micronucleus formation and mutation at the hypoxanthine-guanine phosphoribosyl-transferase (HPRT) locus. Such effects were not observed after irradiation by carbon ions (LET ∼103 keV/μm). Interestingly, progeny of bystander cells from cultures exposed to protons or carbon ions under conditions where GJIC was inhibited harbored reduced oxidative and genetic damage. This mitigating effect was not detected when the cultures were exposed to X-rays. These findings suggest that cellular exposure to proton and heavy charged particle with LET properties similar to those used here can reduce the risk of lesions associated with cancer. The ability of cells to communicate via gap junctions at the time of irradiation appears to impact residual damage in progeny of bystander cells.

Regions With Low Rates of Bystander Cardiopulmonary Resuscitation (CPR) Have Lower Rates of CPR Training in Victoria, Australia.

PubMed

Bray, Janet E; Straney, Lahn; Smith, Karen; Cartledge, Susie; Case, Rosalind; Bernard, Stephen; Finn, Judith

2017-06-05

Bystander cardiopulmonary resuscitation (CPR) more than doubles the chance of surviving an out-of-hospital cardiac arrest. Recent data have shown considerable regional variation in bystander CPR rates across the Australian state of Victoria. This study aims to determine whether there is associated regional variation in rates of CPR training and willingness to perform CPR in these communities. We categorized each Victorian postcode as either a low or high bystander CPR region using data on adult, bystander-witnessed, out-of-hospital cardiac arrests of presumed cardiac etiology (n=7175) from the Victorian Ambulance Cardiac Arrest Registry. We then surveyed adult Victorians (n=404) and compared CPR training data of the respondents from low and high bystander CPR regions. Of the 404 adults surveyed, 223 (55%) resided in regions with low bystander CPR. Compared with respondents from high bystander CPR regions, respondents residing in regions with low bystander CPR had lower rates of CPR training (62% versus 75%, P =0.009) and lower self-ratings for their overall knowledge of CPR (76% versus 84%, P =0.04). There were no differences between the regions in their reasons for not having undergone CPR training or in their willingness to perform CPR. Rates of survival for bystander-witnessed, out-of-hospital cardiac arrests were significantly lower in low bystander CPR regions (15.7% versus 17.0%, P <0.001). This study found lower rates of CPR training and lower survival in regions with lower rates of bystander CPR in Victoria, Australia. Targeting these regions with CPR training programs may improve bystander CPR rates and out-of-hospital cardiac arrest outcomes. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Delayed innocent bystander cell death following hypoxia in Caenorhabditis elegans.

PubMed

Sun, C-L; Kim, E; Crowder, C M

2014-04-01

After hypoxia, cells may die immediately or have a protracted course, living or dying depending on an incompletely understood set of cell autonomous and nonautonomous factors. In stroke, for example, some neurons are thought to die from direct hypoxic injury by cell autonomous primary mechanisms, whereas other so called innocent bystander neurons die from factors released from the primarily injured cells. A major limitation in identifying these factors is the inability of current in vivo models to selectively target a set of cells for hypoxic injury so that the primarily injured cells and the innocent bystanders are clearly delineated. In order to develop such a model, we generated transgenic Caenorhabditis elegans strains where 2-3% of somatic cells were made selectively sensitive to hypoxia. This was accomplished by cell type-specific wild-type rescue in either pharyngeal myocytes or GABAergic neurons of a hypoxia resistance-producing translation factor mutation. Surprisingly, hypoxic targeting of these relatively small subsets of non-essential cells produced widespread innocent bystander cell injury, behavioral dysfunction and eventual organismal death. The hypoxic injury phenotypes of the myocyte or neuron sensitized strains were virtually identical. Using this model, we show that the C. elegans insulin receptor/FOXO transcription factor pathway improves survival when activated only after hypoxic injury and blocks innocent bystander death.

Workplace mobbing: How the victim's coping behavior influences bystander responses.

PubMed

Mulder, Roelie; Bos, Arjan E R; Pouwelse, Mieneke; van Dam, Karen

2017-01-01

Victims of workplace mobbing show diverse coping behavior. We investigated the impact of this behavior on bystander cognitions, emotions, and helping toward the victim, integrating coping literature with attribution theory. Adult part-time university students (N = 161) working at various organizations participated in a study with a 3(Coping: approach/avoidance/neutral) × 2(Gender Victim: male/female) × 2(Gender Bystander: male/female) design. Victims showing approach (vs. avoidance) coping were considered to be more self-reliant and less responsible for the continuation of the mobbing, and they elicited less anger. Continuation responsibility and self-reliance mediated the relationship between the victim's coping behavior and bystanders' helping intentions. Female (vs. male) participants reported more sympathy for the victim and greater willingness to help, and female (vs. male) victims elicited less anger. Theoretical and practical implications of the findings are discussed.

Group vs. Individual Bystander Response to a Violent Assault: A Field Experiment.

ERIC Educational Resources Information Center

Harari, Herbert; And Others

Research studies on group versus individual bystander responses either have involved nonviolent emergencies or laboratory simulations. To investigate group versus individual bystander response to a violent assualt in a natural setting, 80 male college students (from an original pool of 393 white, male students) were observed either individually or…

Sorority Women's and Fraternity Men's Rape Myth Acceptance and Bystander Intervention Attitudes

ERIC Educational Resources Information Center

Bannon, R. Sean; Brosi, Matthew W.; Foubert, John D.

2013-01-01

Sorority women and fraternity men are more likely than other students to be survivors and perpetrators of sexual assault, respectively. The present study examined sorority and fraternity members' rape myth acceptance, bystander efficacy, and bystander willingness to help in potential sexual assault situations. Sorority women were more rejecting of…

Identifiable Images of Bystanders Extracted from Corneal Reflections

PubMed Central

Jenkins, Rob; Kerr, Christie

2013-01-01

Criminal investigations often use photographic evidence to identify suspects. Here we combined robust face perception and high-resolution photography to mine face photographs for hidden information. By zooming in on high-resolution face photographs, we were able to recover images of unseen bystanders from reflections in the subjects' eyes. To establish whether these bystanders could be identified from the reflection images, we presented them as stimuli in a face matching task (Experiment 1). Accuracy in the face matching task was well above chance (50%), despite the unpromising source of the stimuli. Participants who were unfamiliar with the bystanders' faces (n = 16) performed at 71% accuracy [t(15) = 7.64, p<.0001, d = 1.91], and participants who were familiar with the faces (n = 16) performed at 84% accuracy [t(15) = 11.15, p<.0001, d = 2.79]. In a test of spontaneous recognition (Experiment 2), observers could reliably name a familiar face from an eye reflection image. For crimes in which the victims are photographed (e.g., hostage taking, child sex abuse), reflections in the eyes of the photographic subject could help to identify perpetrators. PMID:24386177

Contributions of Personal and Situational Factors to Bystanders' Reactions to School Bullying

ERIC Educational Resources Information Center

Oh, Insoo; Hazler, Richard J.

2009-01-01

The intent of this study was to explore bystanders' personal and situational variables predicting their behavioural reactions to school bullying by investigating a sample of 298 college students who had witnessed bullying during middle or high school. Results indicated that the bystander personal variables, gender and past experience as a bully or…

Conceptualizing the Engaging Bystander Approach to Sexual Violence Prevention on College Campuses

ERIC Educational Resources Information Center

McMahon, Sarah; Postmus, Judy L.; Koenick, Ruth Anne

2011-01-01

Bystander intervention offers promise as a sexual violence prevention tool for student affairs administrators on college campuses, but the conceptualization and definition of the approach is in its infancy and needs further development. In an effort to emphasize the potential role of bystanders in the primary prevention of sexual violence, we put…

Adolescent Bystander Behavior in the School and Online Environments and the Implications for Interventions Targeting Cyberbullying

ERIC Educational Resources Information Center

Patterson, Lisa J.; Allan, Alfred; Cross, Donna

2017-01-01

The aim of this study was to add to the emerging knowledge about the role of bystanders in cyberbullying. To differentiate online versus offline bystander behaviors, 292 Australian children (mean age = 15.2; female = 54.4%) reviewed hypothetical scenarios experimentally manipulated by bystander sex, relationship to target and perpetrator, and…

Cyberbullying Among Adolescent Bystanders: Role of Affective Versus Cognitive Empathy in Increasing Prosocial Cyberbystander Behavior

PubMed Central

Barlińska, Julia; Szuster, Anna; Winiewski, Mikołaj

2018-01-01

The purpose of this study was to investigate if affective (vicarious sharing of emotions) and cognitive empathy (mental perspective taking) induction may stimulate adolescent online bystanders’ intervention in cyberbullying cases. The role of reporting the abuse is crucial because it is a form of active support to the victim, initiated by children, to stop the bullying. The effectiveness of empathy activation in decreasing negative cyberbystander reinforcing behavior has been proved in previous studies. The effects of affective and cognitive empathy activation on positive cyberbystander behavior, defined as reporting the bullying online, were explored in two follow-up studies N = 271 and N = 265. The influence of experiencing cyberbullying as perpetrator, victim, and as determined by gender on prosocial cyberbystander behavior was also controlled. The results indicate that only cognitive empathy activation increases the likelihood of intervening bystander behavior. Neither affective empathy induction, previous experience of cyberperpetration, cybervictimization, nor gender affected the engagement in prosocial bystander behavior. The conclusion of the research is that a program consequently activating more reflective cognitive empathy induction can contribute toward the establishment of healthier behavioral patterns among bystanders to cyberbullying, increasing the probability of their reporting the cyberbullying acts. PMID:29899715

"Please. Don't. Die.": A Grounded Theory Study of Bystander Cardiopulmonary Resuscitation.

PubMed

Mausz, Justin; Snobelen, Paul; Tavares, Walter

2018-02-01

Bystander cardiopulmonary resuscitation (CPR) is an important determinant of survival from out-of-hospital cardiac arrest (OHCA), yet rates of bystander CPR are highly variable. In an effort to promote bystander CPR, the procedure has been streamlined, and ultrashort teaching modalities have been introduced. CPR has been increasingly reconceptualized as simple, safe, and easy to perform; however, current methods of CPR instruction may not adequately prepare lay rescuers for the various logistical, conceptual, and emotional challenges of resuscitating a victim of cardiac arrest. We adopted a constructivist grounded theory methodology to qualitatively explore bystander CPR and invited lay rescuers who had recently (ie, within 1 week) intervened in an OHCA to participate in semistructured interviews and focus groups. We used constant comparative analysis until theoretical saturation to derive a midrange explanatory theory of bystander CPR. We constructed a 3-stage theoretical model describing a common experiential process for lay rescuer intervention in OHCA: Being called to act is disturbing, causing panic, shock, and disbelief that must ultimately be overcome. Taking action to save the victim is complicated by several misconceptions about cardiac arrest, where victims are mistakenly believed to be choking, and agonal respirations are misinterpreted to mean the victim is alive. Making sense of the experience is challenging, at least in the short term, where lay rescuers have to contend with self-doubt, unanswered questions, and uncomfortable emotional reactions to a traumatic event. Our study suggests that current CPR training programs may not adequately prepare lay rescuers for the reality of an OHCA and identifies several key knowledge gaps that should be addressed. The long-term psychological consequences of bystander intervention in OHCA remain poorly understood and warrant further study. © 2018 American Heart Association, Inc.

Delayed innocent bystander cell death following hypoxia in Caenorhabditis elegans

PubMed Central

Sun, C-L; Kim, E; Crowder, C M

2014-01-01

After hypoxia, cells may die immediately or have a protracted course, living or dying depending on an incompletely understood set of cell autonomous and nonautonomous factors. In stroke, for example, some neurons are thought to die from direct hypoxic injury by cell autonomous primary mechanisms, whereas other so called innocent bystander neurons die from factors released from the primarily injured cells. A major limitation in identifying these factors is the inability of current in vivo models to selectively target a set of cells for hypoxic injury so that the primarily injured cells and the innocent bystanders are clearly delineated. In order to develop such a model, we generated transgenic Caenorhabditis elegans strains where 2–3% of somatic cells were made selectively sensitive to hypoxia. This was accomplished by cell type-specific wild-type rescue in either pharyngeal myocytes or GABAergic neurons of a hypoxia resistance-producing translation factor mutation. Surprisingly, hypoxic targeting of these relatively small subsets of non-essential cells produced widespread innocent bystander cell injury, behavioral dysfunction and eventual organismal death. The hypoxic injury phenotypes of the myocyte or neuron sensitized strains were virtually identical. Using this model, we show that the C. elegans insulin receptor/FOXO transcription factor pathway improves survival when activated only after hypoxic injury and blocks innocent bystander death. PMID:24317200

An Examination of the Social Influence Hypothesis of Bystander Intervention in Emergencies.

ERIC Educational Resources Information Center

Teger, Allan I.; Henderson James E.

Data is brought to bear on the social influence hypothesis, according to which the behavior of one bystander influences other bystanders by providing information leading to a definition of the situation. The study placed a subject in an emergency situation in which one of 3 confederates served as a model: (1) male peer; (2) female peer; or (3)…

Bystander effects in radiation-induced genomic instability

NASA Technical Reports Server (NTRS)

Morgan, William F.; Hartmann, Andreas; Limoli, Charles L.; Nagar, Shruti; Ponnaiya, Brian

2002-01-01

Exposure of GM10115 hamster-human hybrid cells to X-rays can result in the induction of chromosomal instability in the progeny of surviving cells. This instability manifests as the dynamic production of novel sub-populations of cells with unique cytogenetic rearrangements involving the "marker" human chromosome. We have used the comet assay to investigate whether there was an elevated level of endogenous DNA breaks in chromosomally unstable clones that could provide a source for the chromosomal rearrangements and thus account for the persistent instability observed. Our results indicate no significant difference in comet tail measurement between non-irradiated and radiation-induced chromosomally unstable clones. Using two-color fluorescence in situ hybridization we also investigated whether recombinational events involving the interstitial telomere repeat-like sequences in GM10115 cells were involved at frequencies higher than random processes would otherwise predict. Nine of 11 clones demonstrated a significantly higher than expected involvement of these interstitial telomere repeat-like sequences at the recombination junction between the human and hamster chromosomes. Since elevated levels of endogenous breaks were not detected in unstable clones we propose that epigenetic or bystander effects (BSEs) lead to the activation of recombinational pathways that perpetuate the unstable phenotype. Specifically, we expand upon the hypothesis that radiation induces conditions and/or factors that stimulate the production of reactive oxygen species (ROS). These reactive intermediates then contribute to a chronic pro-oxidant environment that cycles over multiple generations, promoting chromosomal recombination and other phenotypes associated with genomic instability.

Association of Bystander Cardiopulmonary Resuscitation and Survival According to Ambulance Response Times After Out-of-Hospital Cardiac Arrest.

PubMed

Rajan, Shahzleen; Wissenberg, Mads; Folke, Fredrik; Hansen, Steen Møller; Gerds, Thomas A; Kragholm, Kristian; Hansen, Carolina Malta; Karlsson, Lena; Lippert, Freddy K; Køber, Lars; Gislason, Gunnar H; Torp-Pedersen, Christian

2016-12-20

Bystander-initiated cardiopulmonary resuscitation (CPR) increases patient survival after out-of-hospital cardiac arrest, but it is unknown to what degree bystander CPR remains positively associated with survival with increasing time to potential defibrillation. The main objective was to examine the association of bystander CPR with survival as time to advanced treatment increases. We studied 7623 out-of-hospital cardiac arrest patients between 2005 and 2011, identified through the nationwide Danish Cardiac Arrest Registry. Multiple logistic regression analysis was used to examine the association between time from 911 call to emergency medical service arrival (response time) and survival according to whether bystander CPR was provided (yes or no). Reported are 30-day survival chances with 95% bootstrap confidence intervals. With increasing response times, adjusted 30-day survival chances decreased for both patients with bystander CPR and those without. However, the contrast between the survival chances of patients with versus without bystander CPR increased over time: within 5 minutes, 30-day survival was 14.5% (95% confidence interval [CI]: 12.8-16.4) versus 6.3% (95% CI: 5.1-7.6), corresponding to 2.3 times higher chances of survival associated with bystander CPR; within 10 minutes, 30-day survival chances were 6.7% (95% CI: 5.4-8.1) versus 2.2% (95% CI: 1.5-3.1), corresponding to 3.0 times higher chances of 30-day survival associated with bystander CPR. The contrast in 30-day survival became statistically insignificant when response time was >13 minutes (bystander CPR vs no bystander CPR: 3.7% [95% CI: 2.2-5.4] vs 1.5% [95% CI: 0.6-2.7]), but 30-day survival was still 2.5 times higher associated with bystander CPR. Based on the model and Danish out-of-hospital cardiac arrest statistics, an additional 233 patients could potentially be saved annually if response time was reduced from 10 to 5 minutes and 119 patients if response time was reduced from 7 (the median

Students as Prosocial Bystanders to Sexual Assault: Demographic Correlates of Intervention Norms, Intentions, and Missed Opportunities.

PubMed

Hoxmeier, Jill C; Acock, Alan C; Flay, Brian R

2017-01-01

Sexual assault is a major public health issue. Bystander engagement programs are becoming widely used to combat sexual assault on college campuses. The purpose of this study was to examine students' intervention norms, intentions, opportunities, and behaviors as bystanders to sexual assault. Undergraduate students ( N = 779) completed the Sexual Assault Bystander Behavior Questionnaire in the fall of 2014. The t tests revealed differences in students' intervention norms, intentions, opportunities, and missed opportunities based on sex, race/ethnicity, athletic participation, and fraternity/sorority membership. The findings support the use of additional measures to assess bystander behavior and to identify student subpopulations that may benefit from programs aimed at increasing prosocial intervention.

Predictors of Sexual Assault-Specific Prosocial Bystander Behavior and Intentions: A Prospective Analysis.

PubMed

Austin, Megan J Murphy; Dardis, Christina M; Wilson, Milo S; Gidycz, Christine A; Berkowitz, Alan D

2016-01-01

This study prospectively examined the impact of men's own attitudes and behaviors and perceptions of peer attitudes and behaviors on intentions and engagement in prosocial bystander behavior. Undergraduate men completed surveys at baseline and 4- and 7-month follow-ups. Men's perceptions of peer attitudes and behaviors and their own attitudes and behaviors were both important predictors of intentions. However, men's own attitudes and behaviors appeared to be more robustly predictive of behavior. Intentions to engage in bystander behavior were not predictive of behavior. Results support two specific areas of bystander intervention programming addressing misperceptions of social norms and personal attitudes and behaviors. © The Author(s) 2015.

Role of connexin43 and ATP in long-range bystander radiation damage and oncogenesis in vivo.

PubMed

Mancuso, M; Pasquali, E; Leonardi, S; Rebessi, S; Tanori, M; Giardullo, P; Borra, F; Pazzaglia, S; Naus, C C; Di Majo, V; Saran, A

2011-11-10

Ionizing radiation is a genotoxic agent and human carcinogen. Recent work has questioned long-held dogmas by showing that cancer-associated genetic alterations occur in cells and tissues not directly exposed to radiation, questioning the robustness of the current system of radiation risk assessment. In vitro, diverse mechanisms involving secreted soluble factors, gap junction intercellular communication (GJIC) and oxidative metabolism are proposed to mediate these indirect effects. In vivo, the mechanisms behind long-range 'bystander' responses remain largely unknown. Here, we investigate the role of GJIC in propagating radiation stress signals in vivo, and in mediating radiation-associated bystander tumorigenesis in mouse central nervous system using a mouse model in which intercellular communication is downregulated by targeted deletion of the connexin43 (Cx43) gene. We show that GJIC is critical for transmission of oncogenic radiation damage to the non-targeted cerebellum, and that a mechanism involving adenosine triphosphate release and upregulation of Cx43, the major GJIC constituent, regulates transduction of oncogenic damage to unirradiated tissues in vivo. Our data provide a novel hypothesis for transduction of distant bystander effects and suggest that the highly branched nervous system, similar to the vascular network, has an important role.

Role of TGF-β1 and nitric oxide in the bystander response of irradiated glioma cells

PubMed Central

Shao, C; Folkard, M; Prise, KM

2010-01-01

The radiation-induced bystander effect (RIBE) increases the probability of cellular response and therefore has important implications for cancer risk assessment following low-dose irradiation and for the likelihood of secondary cancers after radiotherapy. However, our knowledge of bystander signaling factors, especially those having long half-lives, is still limited. The present study found that, when a fraction of cells within a glioblastoma population were individually irradiated with helium ions from a particle microbeam, the yield of micronuclei (MN) in the nontargeted cells was increased, but these bystander MN were eliminated by treating the cells with either aminoguanidine (an inhibitor of inducible nitric oxide (NO) synthase) or anti-transforming growth factor β1 (anti-TGF-β1), indicating that NO and TGF-β1 are involved in the RIBE. Intracellular NO was detected in the bystander cells, and additional TGF-β1 was detected in the medium from irradiated T98G cells, but it was diminished by aminoguanidine. Consistent with this, an NO donor, diethylamine nitric oxide (DEANO), induced TGF-β1 generation in T98G cells. Conversely, treatment of cells with recombinant TGF-β1 could also induce NO and MN in T98G cells. Treatment of T98G cells with anti-TGF-β1 inhibited the NO production when only 1% of cells were targeted, but not when 100% of cells were targeted. Our results indicate that, downstream of radiation-induced NO, TGF-β1 can be released from targeted T98G cells and plays a key role as a signaling factor in the RIBE by further inducing free radicals and DNA damage in the nontargeted bystander cells. PMID:17621264

Fas Ligand-Mediated Lysis of Self Bystander Targets by Human Papillomavirus-Specific CD8+ Cytotoxic T Lymphocytes

PubMed Central

Smyth, Mark J.; Krasovskis, Erika; Johnstone, Ricky W.

1998-01-01

Mouse cytotoxic T lymphocytes (CTL) reactive with a H-2Db-presented 9-mer peptide of the human papillomavirus type 16 protein E749-57 (RAHYNIVTF) were generated from the spleen cells of wild-type C57BL/6 (B6) or B6 perforin-deficient (B6.P0) mice. CD8+ B6 CTL displayed peptide-specific perforin- and Fas-mediated lysis of E7-transfected mouse RMA lymphoma cells (RMA-E7), while CD8+ CTL from B6.P0 mice lysed RMA-E7 cells via Fas ligand (FasL) exclusively. Rapid and efficient lysis of syngeneic bystander B6 blasts or RMA cells by either B6 or B6.P0 Ag-activated CTL was mediated by a FasL-Fas mechanism. Fas-resistant bystanders were not lysed, nor were allogeneic Fas-sensitive C3H/HeJ (H-2k) or BALB/c (H-2d) bystander blasts. Interestingly, however, phorbol myristate acetate-ionomycin preactivation of B6.P0 effectors enabled lysis of allogeneic H-2k and H-2d bystanders even in the absence of antigenic stimulation. Lysis of syngeneic bystander cells was always FasL-Fas dependent and required effector-bystander contact and, in particular, an interaction between CTL LFA-1 and bystander ICAM-1. Thus, in the context of major histocompatibility complex class I molecule-peptide ligation of the T-cell receptors of CD8+ CTL, neighboring bystander cells that are syngeneic and Fas sensitive and express the adhesion molecule ICAM-1 are potential targets of CTL attack. PMID:9621057

The influence of a bystander agent's beliefs on children's and adults' decision-making process.

PubMed

Buttelmann, Frances; Buttelmann, David

2017-01-01

The ability to attribute and represent others' mental states (e.g., beliefs; so-called "theory of mind") is essential for participation in human social interaction. Despite a considerable body of research using tasks in which protagonists in the participants' attentional focus held false or true beliefs, the question of automatic belief attribution to bystander agents has received little attention. In the current study, we presented adults and 6-year-olds (N=92) with an implicit computer-based avoidance false-belief task in which participants were asked to place an object into one of three boxes. While doing so, we manipulated the beliefs of an irrelevant human-like or non-human-like bystander agent who was visible on the screen. Importantly, the bystander agent's beliefs were irrelevant for solving the task. Still, children's decision making was significantly influenced by the bystander agent's beliefs even if this was a non-human-like self-propelled object. Such an influence did not become obvious in adults' deliberate decisions but occurred only in their reaction times, which suggests that they also processed the bystander agent's beliefs but were able to suppress the influence of such beliefs on their behavior regulation. The results of a control study (N=53) ruled out low-level explanations and confirmed that self-propelledness of agents is a necessary factor for belief attribution to occur. Thus, not only do humans spontaneously ascribe beliefs to self-propelled bystander agents, but those beliefs even influence meaningful decisions in children. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

Participation in High School Sports and Bystander Intentions, Efficacy to Intervene, and Rape Myth Beliefs.

PubMed

McMahon, Sarah

2015-10-01

Debate exists as to whether male athletes are more prone to commit acts of sexual violence and maintain problematic attitudes about sexual assault. To contribute to the literature on this relationship, this study posed the following research questions: (1) Do those students who participated in high school sports and those who did not differ significantly in their attitudes about sexual violence and willingness to intervene as a bystander? Do these differ among types of rape myths and bystander intervention situations? (2) Within a group of athletes, are there significant differences by gender or type of sport (contact sport vs. non-contact?) To answer these questions, surveys were analyzed with a sample of recent high school graduates the summer before entering college (N = 3,588). Results indicate that there were only minor differences between those students who participated in high school varsity sports and those who did not. Students who participated in sports had greater acceptance of three out of five types of rape myths, and less willingness to intervene with perpetrators after an assault; however, the effect sizes were small. There were no significant differences for bystander efficacy. The interaction between sport and gender was significant, but contact sport was not. The findings suggest that there may be aspects of male athletic participation in sports that needs to be addressed, yet there also exists the potential for engaging athletes as leaders who can act as prosocial bystanders. © The Author(s) 2014.

Low-dose energetic protons induce adaptive and bystander effects that protect human cells against DNA damage caused by a subsequent exposure to energetic iron ions

PubMed Central

Buonanno, Manuela; De Toledo, Sonia M.; Howell, Roger W.; Azzam, Edouard I.

2015-01-01

During interplanetary missions, astronauts are exposed to mixed types of ionizing radiation. The low ‘flux’ of the high atomic number and high energy (HZE) radiations relative to the higher ‘flux’ of low linear energy transfer (LET) protons makes it highly probable that for any given cell in the body, proton events will precede any HZE event. Whereas progress has been made in our understanding of the biological effects of low-LET protons and high-LET HZE particles, the interplay between the biochemical processes modulated by these radiations is unclear. Here we show that exposure of normal human fibroblasts to a low mean absorbed dose of 20 cGy of 0.05 or 1-GeV protons (LET ∼ 1.25 or 0.2 keV/μm, respectively) protects the irradiated cells (P < 0.0001) against chromosomal damage induced by a subsequent exposure to a mean absorbed dose of 50 cGy from 1 GeV/u iron ions (LET ∼ 151 keV/μm). Surprisingly, unirradiated (i.e. bystander) cells with which the proton-irradiated cells were co-cultured were also significantly protected from the DNA-damaging effects of the challenge dose. The mitigating effect persisted for at least 24 h. These results highlight the interactions of biological effects due to direct cellular traversal by radiation with those due to bystander effects in cell populations exposed to mixed radiation fields. They show that protective adaptive responses can spread from cells targeted by low-LET space radiation to bystander cells in their vicinity. The findings are relevant to understanding the health hazards of space travel. PMID:25805407

A Bystander Bullying Psychoeducation Program with Middle School Students: A Preliminary Report

ERIC Educational Resources Information Center

Midgett, Aida; Doumas, Diana; Sears, Dara; Lundquist, Amanda; Hausheer, Robin

2015-01-01

This study evaluated the effectiveness of a brief, stand-alone bystander bullying psychoeducation program for middle school students. The purpose of the program was to train students to take action as peer advocates. Pre- and post-tests indicated that after completing the 90-minute psychoeducation program, students reported an increase in their…

Total and Marginal Cost Analysis for a High School Based Bystander Intervention

ERIC Educational Resources Information Center

Bush, Joshua L.; Bush, Heather M.; Coker, Ann L.; Brancato, Candace J.; Clear, Emily R.; Recktenwald, Eileen A.

2018-01-01

Costs of providing the Green Dot bystander-based intervention, shown to be effective in the reduction of sexual violence among Kentucky high school students, were estimated based on data from a large cluster-randomized clinical trial. Rape Crisis Center Educators were trained to provide Green Dot curriculum to students. Implementing Green Dot in…

Cell cycle tracking for irradiated and unirradiated bystander cells in a single colony with exposure to a soft X-ray microbeam.

PubMed

Kaminaga, Kiichi; Noguchi, Miho; Narita, Ayumi; Hattori, Yuya; Usami, Noriko; Yokoya, Akinari

2016-11-01

To establish a new experimental technique to explore the photoelectric and subsequent Auger effects on the cell cycles of soft X-ray microbeam-irradiated cells and unirradiated bystander cells in a single colony. Several cells located in the center of a microcolony of HeLa-Fucci cells consisting of 20-80 cells were irradiated with soft X-ray (5.35 keV) microbeam using synchrotron radiation as a light source. All cells in the colony were tracked for 72 h by time-lapse microscopy imaging. Cell cycle progression, division, and death of each cell in the movies obtained were analyzed by pedigree assay. The number of cell divisions in the microcolony was also determined. The fates of these cells were clarified by tracking both irradiated and unirradiated bystander cells. Irradiated cells showed significant cell cycle retardation, explosive cell death, or cell fusion after a few divisions. These serious effects were also observed in 15 and 26% of the bystander cells for 10 and 20 Gy irradiation, respectively, and frequently appeared in at least two daughter or granddaughter cells from a single-parent cell. We successfully tracked the fates of microbeam-irradiated cells and unirradiated bystander cells with live cell recordings, which have revealed the dynamics of soft X-ray irradiated and unirradiated bystander cells for the first time. Notably, cell deaths or cell cycle arrests frequently arose in closely related cells. These details would not have been revealed by a conventional immunostaining imaging method. Our approach promises to reveal the dynamic cellular effects of soft X-ray microbeam irradiation and subsequent Auger processes from various endpoints in future studies.

That's What Friends Are For: Bystander Responses to Friends or Strangers at Risk for Party Rape Victimization.

PubMed

Katz, Jennifer; Pazienza, Rena; Olin, Rachel; Rich, Hillary

2015-10-01

The present research examined bystander responses to potential party rape scenarios involving either a friend or a stranger at risk. Undergraduate students (N = 151) imagined attending a party and seeing a man lead an intoxicated woman (friend or stranger) into a bedroom. After random assignment to conditions, participants reported on intentions to help, barriers to helping, victim blame, and empathic concern. As expected, based on their shared social group membership, bystanders intended to offer more help to friends than to strangers. Bystanders also reported more personal responsibility to help and more empathic concern when the potential victim was a friend rather than stranger. Observing a friend versus stranger at risk did not affect audience inhibition or perceived victim blame. Compared with women, men reported more blame and less empathic concern for potential victims. However, there were no gender differences in bystander intent to help or barriers to helping. In multivariate analyses, both responsibility to help and empathic concern for the potential victim uniquely predicted bystanders' intent to help a woman at risk for party rape. Results suggest that promoting social identification with peers at risk could increase bystander intervention. © The Author(s) 2014.

Non-targeted and delayed effects of exposure to ionizing radiation: II. Radiation-induced genomic instability and bystander effects in vivo, clastogenic factors and transgenerational effects

NASA Technical Reports Server (NTRS)

Morgan, William F.

2003-01-01

The goal of this review is to summarize the evidence for non-targeted and delayed effects of exposure to ionizing radiation in vivo. Currently, human health risks associated with radiation exposures are based primarily on the assumption that the detrimental effects of radiation occur in irradiated cells. Over the years a number of non-targeted effects of radiation exposure in vivo have been described that challenge this concept. These include radiation-induced genomic instability, bystander effects, clastogenic factors produced in plasma from irradiated individuals that can cause chromosomal damage when cultured with nonirradiated cells, and transgenerational effects of parental irradiation that can manifest in the progeny. These effects pose new challenges to evaluating the risk(s) associated with radiation exposure and understanding radiation-induced carcinogenesis.

Evaluation of the Green Dot Bystander Intervention to Reduce Interpersonal Violence Among College Students Across Three Campuses.

PubMed

Coker, Ann L; Fisher, Bonnie S; Bush, Heather M; Swan, Suzanne C; Williams, Corrine M; Clear, Emily R; DeGue, Sarah

2015-12-01

Evidence suggests that interventions to engage bystanders in violence prevention increase bystander intentions and efficacy to intervene, yet the impact of such programs on violence remains unknown. This study compared rates of violence by type among undergraduate students attending a college campus with the Green Dot bystander intervention (n = 2,768) with students at two colleges without bystander programs (n = 4,258). Violent victimization rates were significantly (p < .01) lower among students attending the campus with Green Dot relative to the two comparison campuses. Violence perpetration rates were lower among males attending the intervention campus. Implications of these results for research and practice are discussed. © The Author(s) 2014.

Evaluation of the Green Dot Bystander Intervention to Reduce Interpersonal Violence Among College Students Across Three Campuses

PubMed Central

Coker, Ann L.; Fisher, Bonnie S.; Bush, Heather M.; Swan, Suzanne C.; Williams, Corrine M.; Clear, Emily R.; DeGue, Sarah

2018-01-01

Evidence suggests that interventions to engage bystanders in violence prevention increase bystander intentions and efficacy to intervene, yet the impact of such programs on violence remains unknown. This study compared rates of violence by type among undergraduate students attending a college campus with the Green Dot bystander intervention (n = 2,768) with students at two colleges without bystander programs (n = 4,258). Violent victimization rates were significantly (p < .01) lower among students attending the campus with Green Dot relative to the two comparison campuses. Violence perpetration rates were lower among males attending the intervention campus. Implications of these results for research and practice are discussed. PMID:25125493

The future impacts of non-targeted effects.

PubMed

Bright, Scott; Kadhim, Munira

2018-04-11

Ionizing radiation was traditionally thought to exert its detrimental effects through interaction with sensitive cellular targets, nuclear DNA being of most importance. This theory has since merged with a more recently described radiation response called non-targeted effects (NTE). This review will briefly look at the various types of NTE and the potential implications they may have for radiobiology research and its applications. The most well-known NTE are genomic instability (GI) and bystander effects (BE). Other NTE include abscopal effects, which are similar to bystander effects but are generally based in a clinical environment with immune involvement as the defining feature. Currently, our understanding of NTE is limited to certain signaling pathways/molecules, and as yet there is no theory that describes or can accurately predict the occurrence or outcome of these NTE. There are numerous groups investigating these processes in vitro and in vivo, and thus steady progress is being made. Developing a deeper understanding of NTE has potential impacts for therapy and diagnosis, safer occupational exposures, space flight and our general understanding of radiation biology.

Bystanders not so innocent after all.

PubMed

Batten, Marcel; Ghilardi, Nico

2012-06-29

Interleukin 27 (IL-27) regulates immune responses, including T helper 17 (Th17) cell activity. In this issue of Immunity, Hirahara et al. (2012) demonstrate that IL-27 suppresses Th17 cells in trans through induction of the inhibitory ligand PD-L1 on bystander T cells. Copyright © 2012 Elsevier Inc. All rights reserved.

Collaborative effects of bystander-initiated cardiopulmonary resuscitation and prehospital advanced cardiac life support by physicians on survival of out-of-hospital cardiac arrest: a nationwide population-based observational study.

PubMed

Yasunaga, Hideo; Horiguchi, Hiromasa; Tanabe, Seizan; Akahane, Manabu; Ogawa, Toshio; Koike, Soichi; Imamura, Tomoaki

2010-01-01

There are inconsistent data about the effectiveness of prehospital physician-staffed advanced cardiac life support (ACLS) on the outcomes of out-of-hospital cardiac arrest (OHCA). Furthermore, the relative importance of bystander-initiated cardiopulmonary resuscitation (BCPR) and ACLS and the effectiveness of their combination have not been clearly demonstrated. Using a prospective, nationwide, population-based registry of all OHCA patients in Japan, we enrolled 95,072 patients whose arrests were witnessed by bystanders and 23,127 patients witnessed by emergency medical service providers between 2005 and 2007. We divided the bystander-witnessed arrest patients into Group A (ACLS by emergency life-saving technicians without BCPR), Group B (ACLS by emergency life-saving technicians with BCPR), Group C (ACLS by physicians without BCPR) and Group D (ACLS by physicians with BCPR). The outcome data included 1-month survival and neurological outcomes determined by the cerebral performance category. Among the 95,072 bystander-witnessed arrest patients, 7,722 (8.1%) were alive at 1 month, including 2,754 (2.9%) with good performance and 3,171 (3.3%) with vegetative status or worse. BCPR occurred in 42% of bystander-witnessed arrests. In comparison with Group A, the rates of good-performance survival were significantly higher in Group B (odds ratio (OR), 2.23; 95% confidence interval, 2.05 to 2.42; P < 0.01) and Group D (OR, 2.80; 95% confidence interval, 2.28 to 3.43; P < 0.01), while no significant difference was seen for Group C (OR, 1.18; 95% confidence interval, 0.86 to 1.61; P = 0.32). The occurrence of vegetative status or worse at 1 month was highest in Group C (OR, 1.92; 95% confidence interval, 1.55 to 2.37; P < 0.01). In this registry-based study, BCPR significantly improved the survival of OHCA with good cerebral outcome. The groups with BCPR and ACLS by physicians had the best outcomes. However, receiving ACLS by physicians without preceding BCPR significantly

Caffeine and theanine exert opposite effects on attention under emotional arousal.

PubMed

Giles, Grace E; Mahoney, Caroline R; Brunyé, Tad T; Taylor, Holly A; Kanarek, Robin B

2017-01-01

Tea is perceived as more relaxing than coffee, even though both contain caffeine. L-theanine in tea may account for the difference. Consumed together, caffeine and theanine exert similar cognitive effects to that of caffeine alone, but exert opposite effects on arousal, in that caffeine accentuates and theanine mitigates physiological and felt stress responses. We evaluated whether caffeine and theanine influenced cognition under emotional arousal. Using a double-blind, repeated-measures design, 36 participants received 4 treatments (200 mg caffeine + 0 mg theanine, 0 mg caffeine + 200 mg theanine, 200 mg caffeine + 200 mg theanine, 0 mg caffeine + 0 mg theanine) on separate days. Emotional arousal was induced by highly arousing negative film clips and pictures. Mood, salivary cortisol, and visual attention were evaluated. Caffeine accentuated global processing of visual attention on the hierarchical shape task (p < 0.05), theanine accentuated local processing (p < 0.05), and the combination did not differ from placebo. Caffeine reduced flanker conflict difference scores on the Attention Network Test (p < 0.05), theanine increased difference scores (p < 0.05), and the combination did not differ from placebo. Thus, under emotional arousal, caffeine and theanine exert opposite effects on certain attentional processes, but when consumed together, they counteract the effects of each other.

Bystanders' responses to offline bullying and cyberbullying: The role of empathy and normative beliefs about aggression.

PubMed

Machackova, Hana; Pfetsch, Jan

2016-04-01

Cyberbullying often takes place with the virtual presence or knowledge of bystanders. While we have some evidence about the determinants of bystanders' responses to offline bullying, we lack empirical studies concerning the variables that influence bystanders' responses to cyberbullying. The current study examines bystanders' responses to offline bullying and cyberbullying incidents. Two types of responses were captured: support toward the victims and the reinforcement of bullies' actions. Using data from 321 German adolescents (ages 12-18; M = 14.99; 44% girls), the association between bystanders' responses and normative beliefs about verbal aggression and cyberaggression, and affective and cognitive empathy, were tested in a path model. Both types of normative beliefs positively predicted the reinforcement of bullies, and normative belief about verbal aggression also predicted support for the victims of offline bullying. Both types of empathy predicted support in offline bullying, but only affective empathy predicted support in cyberbullying. There was no link between affective or cognitive empathy to the reinforcement of bullies. Moreover, bystanders' tendencies to respond supportively to the victim or to reinforce the bully were rather consistent in both cyber- and offline bullying, but there was no link between support and reinforcement. The findings are discussed with regard to implications for prevention and intervention efforts. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Building upon Bystander Intervention: A Multi-Component Prevention Programming Approach for University Sorority Members

ERIC Educational Resources Information Center

Steward, Jennifer M.

2017-01-01

Sexual violence on college campuses is a pervasive problem with the potential for extensive physical and psychological health consequences. Institutions have begun implementing prevention programs; however, more research is needed to understand whether these programs are effective. Bystander intervention programs have increased in popularity…

Low-dose energetic protons induce adaptive and bystander effects that protect human cells against DNA damage caused by a subsequent exposure to energetic iron ions.

PubMed

Buonanno, Manuela; De Toledo, Sonia M; Howell, Roger W; Azzam, Edouard I

2015-05-01

During interplanetary missions, astronauts are exposed to mixed types of ionizing radiation. The low 'flux' of the high atomic number and high energy (HZE) radiations relative to the higher 'flux' of low linear energy transfer (LET) protons makes it highly probable that for any given cell in the body, proton events will precede any HZE event. Whereas progress has been made in our understanding of the biological effects of low-LET protons and high-LET HZE particles, the interplay between the biochemical processes modulated by these radiations is unclear. Here we show that exposure of normal human fibroblasts to a low mean absorbed dose of 20 cGy of 0.05 or 1-GeV protons (LET ∼ 1.25 or 0.2 keV/μm, respectively) protects the irradiated cells (P < 0.0001) against chromosomal damage induced by a subsequent exposure to a mean absorbed dose of 50 cGy from 1 GeV/u iron ions (LET ∼ 151 keV/μm). Surprisingly, unirradiated (i.e. bystander) cells with which the proton-irradiated cells were co-cultured were also significantly protected from the DNA-damaging effects of the challenge dose. The mitigating effect persisted for at least 24 h. These results highlight the interactions of biological effects due to direct cellular traversal by radiation with those due to bystander effects in cell populations exposed to mixed radiation fields. They show that protective adaptive responses can spread from cells targeted by low-LET space radiation to bystander cells in their vicinity. The findings are relevant to understanding the health hazards of space travel. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Control, Norms, and Attitudes: Differences Between Students Who Do and Do Not Intervene as Bystanders to Sexual Assault.

PubMed

Hoxmeier, Jill C; Flay, Brian R; Acock, Alan C

2016-01-14

Sexual assault is a major concern on the U.S. college campus. Engaging students as pro-social bystanders has become more common as a potentially effective mechanism for reducing the incidence of sexual assault and mitigating the harm of assaults that have already occurred. Understanding the influences of pro-social bystander behavior is imperative to developing effective programs, and the use of an evidence-based theoretical framework can help identify the differences between students who intervene and those who do not when presented with the opportunity. A sample of 815 undergraduate university students completed the Sexual Assault Bystander Behavior Questionnaire, a survey based on the theory of planned behavior (TPB) that investigates students' perceived behavioral control to intervene, subjective norms that support intervening, attitudes toward intervening, and intent to intervene in the future. Two-tailed t tests revealed interveners reported significantly greater perceived behavioral control than non-interveners for eight of the 12 intervention behaviors, more supportive subjective norms than non-interveners for seven of the 12 intervention behaviors, more positive attitudes than non-interveners for only one of the 12 intervention behaviors, and greater intent to intervene in the future for six of the 12 intervention behaviors. Differences in the four TPB variables were not consistent for the 12 intervention behaviors. The use of a theoretical framework found to be effective in explaining-and changing-other health-related behaviors, and the inquiry into students' opportunities to intervene to compare against their reported intervention behaviors, is new to this body of literature and contributes to the understanding of the influences of pro-social bystander behavior. © The Author(s) 2016.

On Standby? A Comparison of Online and Offline Witnesses to Bullying and Their Bystander Behaviour

ERIC Educational Resources Information Center

Quirk, Roslynn; Campbell, Marilyn

2015-01-01

Given their ubiquitous presence as witnesses to school-yard bullying, the role of the "bystander" has been studied extensively. The prevalence and behaviour of bystanders to "cyberbullying," however, is less understood. In an anonymous, school-based questionnaire, 716 secondary school students from South-East Queensland…

Bystander Interventions for Sexual Assault and Dating Violence on College Campuses: Are We Putting Bystanders in Harm's Way?

ERIC Educational Resources Information Center

Witte, Tricia H.; Casper, Deborah M.; Hackman, Christine L.; Mulla, Mazheruddin M.

2017-01-01

Objective: The present study investigated the well-being of bystanders who witness and intervene in sexual assault and dating violence situations on campus. Participants: Participants were 321 young men and women from a large university in the southeastern United States. Methods: Participants completed a survey at the end of the Spring semester of…

Human Lung Cancer Risks from Radon – Part III - Evidence of Influence of Combined Bystander and Adaptive Response Effects on Radon Case-Control Studies - A Microdose Analysis

PubMed Central

Leonard, Bobby E.; Thompson, Richard E.; Beecher, Georgia C.

2012-01-01

Since the publication of the BEIR VI (1999) report on health risks from radon, a significant amount of new data has been published showing various mechanisms that may affect the ultimate assessment of radon as a carcinogen, in particular the potentially deleterious Bystander Effect (BE) and the potentially beneficial Adaptive Response radio-protection (AR). The case-control radon lung cancer risk data of the pooled 13 European countries radon study (Darby et al 2005, 2006) and the 8 North American pooled study (Krewski et al 2005, 2006) have been evaluated. The large variation in the odds ratios of lung cancer from radon risk is reconciled, based on the large variation in geological and ecological conditions and variation in the degree of adaptive response radio-protection against the bystander effect induced lung damage. The analysis clearly shows Bystander Effect radon lung cancer induction and Adaptive Response reduction in lung cancer in some geographical regions. It is estimated that for radon levels up to about 400 Bq m−3 there is about a 30% probability that no human lung cancer risk from radon will be experienced and a 20% probability that the risk is below the zero-radon, endogenic spontaneous or perhaps even genetically inheritable lung cancer risk rate. The BEIR VI (1999) and EPA (2003) estimates of human lung cancer deaths from radon are most likely significantly excessive. The assumption of linearity of risk, by the Linear No-Threshold Model, with increasing radon exposure is invalid. PMID:22942874

Blame Conformity: Innocent Bystanders Can Be Blamed for a Crime as a Result of Misinformation from a Young, but Not Elderly, Adult Co-Witness

PubMed Central

Thorley, Craig

2015-01-01

This study examined whether or not exposing an eyewitness to a co-witness statement that incorrectly blames an innocent bystander for a crime can increase the likelihood of the eyewitness subsequently blaming the innocent bystander for the crime. It also examined whether or not the perceived age of the co-witness influences this effect. Participant eyewitnesses first watched a video of a crime featuring a perpetrator and an innocent bystander. They then read one of six bogus co-witness statements about the crime. All were presented as having been written by a female co-witness and they differed in terms of her age (young adult or elderly) and who she blamed for the crime (the perpetrator, the innocent bystander, or nobody). One week later the participants were asked who committed the crime. When the young adult co-witness had blamed the innocent bystander just over 40% of participants subsequently did the same. Few participants (less than 8%) in the other conditions subsequently blamed the innocent bystander. The elderly co-witness was also rated as less credible, less competent, and less accurate than the younger co-witness suggesting eyewitnesses were less likely to be influenced by her incorrect statement as they perceived her to be a less reliable source of information. The applied implications of these findings are discussed. PMID:26230523

Blame Conformity: Innocent Bystanders Can Be Blamed for a Crime as a Result of Misinformation from a Young, but Not Elderly, Adult Co-Witness.

PubMed

Thorley, Craig

2015-01-01

This study examined whether or not exposing an eyewitness to a co-witness statement that incorrectly blames an innocent bystander for a crime can increase the likelihood of the eyewitness subsequently blaming the innocent bystander for the crime. It also examined whether or not the perceived age of the co-witness influences this effect. Participant eyewitnesses first watched a video of a crime featuring a perpetrator and an innocent bystander. They then read one of six bogus co-witness statements about the crime. All were presented as having been written by a female co-witness and they differed in terms of her age (young adult or elderly) and who she blamed for the crime (the perpetrator, the innocent bystander, or nobody). One week later the participants were asked who committed the crime. When the young adult co-witness had blamed the innocent bystander just over 40% of participants subsequently did the same. Few participants (less than 8%) in the other conditions subsequently blamed the innocent bystander. The elderly co-witness was also rated as less credible, less competent, and less accurate than the younger co-witness suggesting eyewitnesses were less likely to be influenced by her incorrect statement as they perceived her to be a less reliable source of information. The applied implications of these findings are discussed.

Social Capital and Bystander Behavior in Bullying: Internalizing Problems as a Barrier to Prosocial Intervention.

PubMed

Jenkins, Lyndsay N; Fredrick, Stephanie Secord

2017-04-01

Theory and research suggests that individuals with greater social capital (i.e., resources and benefits gained from relationships, experiences, and social interactions) may be more likely to be active, prosocial bystanders in bullying situations. Therefore, the goal of the current study was to examine the association of social capital (social support and social skills) with prosocial bystander behavior, and the role of internalizing problems as a potential barrier to this relation among 299 students (45.8% girls, 95% White) in sixth, seventh, and eighth grades. Results indicate a positive relation between social capital and prosocial bystander behavior. In addition, internalizing problems were a significant risk factor that may hinder youth-particularly girls-from engaging in defending behavior. Prosocial bystanders are an essential component to prevent and reduce bullying and further research is needed to better understand how to foster prosocial behavior in bullying situations, perhaps by utilizing social capital, related to school bullying.

Bystander position taking in school bullying: the role of positive identity, self-efficacy, and self-determination.

PubMed

Tsang, Sandra K M; Hui, Eadaoin K P; Law, Bella C M

2011-01-01

School bullying has become an explicit, burgeoning problem challenging the healthy development of children and adolescents in Hong Kong. Many bullying prevention and intervention programs focus on victims and bullies, with bystanders treated as either nonexistent or irrelevant. This paper asserts that bystanders actually play pivotal roles in deciding whether the bullying process and dynamics are benign or adversarial. Bystanders' own abilities and characteristics often influence how they respond to victims and bullies. "P.A.T.H.S. to Adulthood: A Jockey Club Youth Enhancement Scheme" (P.A.T.H.S. = Positive Adolescent Training through Holistic Social Programmes) is an evidence-based positive youth development program which shows that primary intervention programs have constructive impacts on junior secondary school students' beliefs and behavior. This paper asserts that intrapsychic qualities, namely identity, self-efficacy, and self-determination, greatly influence how bystanders react in school bullying situations. The paper also explains how classroom-based educational programs based on the P.A.T.H.S. model have been designed to help junior secondary school students strengthen these characteristics, so that they can be constructive bystanders when they encounter school bullying.

The effect of bracing availability on one-hand isometric force exertion capability.

PubMed

Jones, Monica L H; Reed, Matthew P; Chaffin, Don B

2013-01-01

Environmental obstructions that workers encounter can kinematically limit the postures that they can achieve. However, such obstructions can also provide an opportunity for additional support by bracing with the hand, thigh or other body part. The reaction forces on bracing surfaces, which are in addition to those acting at the feet and task hand, are hypothesised to improve force exertion capability, and become required inputs to biomechanical analysis of tasks with bracing. The effects of kinematic constraints and associated bracing opportunities on isometric hand force were quantified in a laboratory study of 22 men and women. Analyses of one-hand maximal push, pull and lift tasks demonstrated that bracing surfaces available at the thighs and non-task hand enabled participants to exert an average of 43% more force at the task hand. Task hand force direction deviated significantly from the nominal direction for exertions performed with bracing at both medium and low task hand locations. This study quantifies the effect of bracing on kinematically constrained force exertions. Knowledge that appropriate bracing surfaces can substantially increase hand force is critical to the evaluation of task-oriented strength capability. Force estimates may also involve large off-axis components, which have clear implications for ergonomic analyses of manual tasks.

Roles of Fatalism and Parental Support in the Relationship between Bullying Victimization and Bystander Behaviors

ERIC Educational Resources Information Center

Li, Yiqiong; Chen, Peter Y.; Chen, Fu-Li; Wu, Wen-Chi

2015-01-01

This article examines how past bullied victims engage two types of bystander behaviors (defender and outsider) when they witness bullying situations.We also investigate if fatalism mediates the relationship between past victimization and two bystander behaviors. Finally, we test if parental support moderates the relationship between fatalism and…

What Would You Do? Strategies for Bystander Intervention to Prevent Sexual Violence by College Students

ERIC Educational Resources Information Center

McMahon, Sarah; Hoffman, Melanie Lowe; McMahon, Sheila M.; Zucker, Sharon; Koenick, Ruth Anne

2013-01-01

Bystander education is an increasingly utilized strategy for addressing sexual assault prevention and intervention on U.S. college campuses. Given the paramount importance of peers among college students, what types of pro-social bystander interventions do students themselves deem feasible in the campus context? Drawing on self-reports from…

Neighborhood characteristics, bystander automated external defibrillator use, and patient outcomes in public out-of-hospital cardiac arrest.

PubMed

Andersen, Lars W; Holmberg, Mathias J; Granfeldt, Asger; Løfgren, Bo; Vellano, Kimberly; McNally, Bryan F; Siegerink, Bob; Kurth, Tobias; Donnino, Michael W

2018-05-01

Automated external defibrillators (AEDs) can be used by bystanders to provide rapid defibrillation for patients with out-of-hospital cardiac arrest (OHCA). Whether neighborhood characteristics are associated with AED use is unknown. Furthermore, the association between AED use and outcomes has not been well characterized for all (i.e. shockable and non-shockable) public OHCAs. We included public, non-911-responder witnessed OHCAs registered in the Cardiac Arrest Registry to Enhance Survival (CARES) between 2013 and 2016. The primary patient outcome was survival to hospital discharge with a favorable functional outcome. We first assessed the association between neighborhood characteristics and bystander AED use using logistic regression and then assessed the association between bystander AED use and patient outcomes in a propensity score matched cohort. 25,182 OHCAs were included. Several neighborhood characteristics, including the proportion of people living alone, the proportion of white people, and the proportion with a high-school degree or higher, were associated with bystander AED use. 5132 OHCAs were included in the propensity score-matched cohort. Bystander AED use was associated with an increased risk of a favorable functional outcome (35% vs. 25%, risk difference: 9.7% [95% confidence interval: 7.2%, 12.2%], risk ratio: 1.38 [95% confidence interval: 1.27, 1.50]). This was driven by increased favorable functional outcomes with AED use in patients with shockable rhythms (58% vs. 39%) but not in patients with non-shockable rhythms (10% vs. 10%). Specific neighborhood characteristics were associated with bystander AED use in OHCA. Bystander AED use was associated with an increase in favorable functional outcome. Copyright © 2018 Elsevier B.V. All rights reserved.

Challenges of Bystander Intervention in Male-Dominated Professional Sport: Lessons From the Australian Football League.

PubMed

Corboz, Julienne; Flood, Michael; Dyson, Sue

2016-03-01

Programs aimed at preventing violence against women have increasingly adopted bystander approaches, yet large gaps remain in our knowledge about what drives bystanders to act or not, particularly in settings where there is an increased risk of violence against women occurring. This article contributes to this gap by examining data from research with professional male athletes from the Australian Football League. Drawing from a mixed methods approach, including a survey and interviews with football players, we outline some of the challenges to bystander intervention faced by professional athletes and discuss some of the possible similarities and differences between these and other groups of men. © The Author(s) 2015.

Bystander CD4+ T lymphocytes survive in HIV-infected human lymphoid tissue

NASA Technical Reports Server (NTRS)

Grivel, Jean-Charles; Biancotto, Angelique; Ito, Yoshinori; Lima, Rosangela G.; Margolis, Leonid B.

2003-01-01

HIV infection is associated with depletion of CD4(+) T cells. The mechanisms of this phenomenon remain to be understood. In particular, it remains controversial whether and to what extent uninfected ("bystander") CD4(+) T cells die in HIV-infected individuals. We address this question using a system of human lymphoid tissue ex vivo. Tissue blocks were inoculated with HIV-1. After productive infection was established, they were treated with the reverse transcriptase inhibitor nevirapine to protect from infection those CD4(+) T cells that had not yet been infected. These CD4(+) T cells residing in HIV-infected tissue are by definition bystanders. Our results demonstrate that after nevirapine application the number of bystander CD4(+) T cells is conserved. Thus, in the context of HIV-infected human lymphoid tissue, productive HIV infection kills infected cells but is not sufficient to cause the death of a significant number of uninfected CD4(+) T cells.

Brentuximab vedotin exerts profound antiproliferative and pro-apoptotic efficacy in CD30-positive as well as cocultured CD30-negative germ cell tumour cell lines.

PubMed

Schönberger, Stefan; van Beekum, Cornelius; Götz, Barbara; Nettersheim, Daniel; Schorle, Hubert; Schneider, Dominik T; Casati, Anna; Craveiro, Rogerio B; Calaminus, Gabriele; Dilloo, Dagmar

2018-01-01

Prognosis in patients suffering from high-risk, refractory and relapsed germ cell tumours (GCT) often comprising of CD30-positive embryonal carcinoma (EC) components remains poor. Thus, novel treatment strategies are warranted. The antibody-drug conjugate (ADC) brentuximab vedotin delivers the potent antimitotic drug monomethyl auristatin E (MMAE) to CD30-expressing tumour cells. After CD30 binding, internalization and intracellular linker cleavage cytotoxic MMAE can efflux and eradicate neighbouring CD30-negative cells. To analyse cytotoxicity and a potential bystander effect of brentuximab vedotin in GCT, we established an in vitro coculture model mimicking GCT of heterogeneous CD30 positivity and measured cell viability, proliferation and apoptosis after exposure to brentuximab vedotin and unbound MMAE by MTS- and flow cytometry-based CFSE/Hoechst assay. CD30 expression being assessed by quantitative RT-PCR and immunohistochemistry was apparent in all EC cell lines with different intensity. Brentuximab vedotin abrogates cell viability of CD30-positive GCT27 EC line exerting marked time-dependent antiproliferative and pro-apoptotic activity. CD30-negative JAR cultured alone barely responds to brentuximab vedotin, while in coculture with GCT27 brentuximab vedotin induces clear dose-dependent cytotoxicity. Cellular proliferation and cell death are significantly enhanced in CD30-negative JAR cocultured with CD30-positive GCT27 compared to JAR cultured alone in proof of substantial bystander activity of brentuximab vedotin in CD30-negative GCT. We present first evidence that in an in vitro model mimicking GCT of heterogeneous histology, brentuximab vedotin exerts potent antiproliferative and pro-apoptotic activity against both CD30-positive as well as CD30-negative GCT subsets. Our results strongly support translational efforts to evaluate clinical efficacy of brentuximab vedotin in high-risk GCT of heterogeneous CD30 positivity. © 2017 The Authors. Journal of

See Something, Do Something: Predicting Sexual Assault Bystander Intentions in the U.S. Military.

PubMed

Holland, Kathryn J; Rabelo, Verónica Caridad; Cortina, Lilia

2016-09-01

Sexual assault is a pervasive problem in the U.S. military, especially against women. Bystander intervention is increasingly promoted as important for reducing sexual violence, and it may be particularly helpful in contexts with high rates of sexual violence. Bystander training encourages and enables people to intervene safely and stop sexual violence. In this study, we drew from an ecological model to investigate intrapersonal, microsystem, and exosystem factors that predicted Service members' assumption of personal responsibility to intervene in an alcohol-involved sexual assault. Moreover, we examined how these predictors played a role in decisions about how to intervene: confronting the perpetrator, assisting the victim, or finding someone to help. We analyzed data from 24,610 active duty personnel collected by the Department of Defense. Several factors significantly related to Service members' bystander intentions: gender, rank, morale, attitudes about sexual assault, training, and trust in the military sexual assault system predicted the likelihood and method of bystander intervention. These findings help identify how and why people intervene (or fail to intervene) when they witness situations that could develop into sexual violence. © Society for Community Research and Action 2016.

Leukocyte function-associated antigen-1-dependent lysis of Fas+ (CD95+/Apo-1+) innocent bystanders by antigen-specific CD8+ CTL.

PubMed

Kojima, H; Eshima, K; Takayama, H; Sitkovsky, M V

1997-09-15

Exquisite specificity toward Ag-bearing cells (cognate targets) is one of the most important properties of CD8+ CTL-mediated cytotoxicity. Using highly Ag-specific CD8+ CTL lines and clones, which spare noncognate, Ag-free targets, we found that in the presence of Ag-bearing targets the CTL acquire the ability to lyse noncognate target cells (bystanders). It is shown that the unexpectedly rapid and efficient lysis of bystanders by Ag-activated CTL is mediated by a Fas ligand (FasL)/Fas-based mechanism and does not depend on perforin. The CTL lysed Fas-expressing bystanders, but spared the Fas-negative or anti-Fas mAb-resistant bystander cells. Accordingly, the FasL-deficient gld/gld CTL did not kill bystanders, while perforin-deficient CTL did. Unlike anti-Fas mAb-induced cell death, the lysis of bystanders was not only FasL/Fas dependent but also required adhesion molecule LFA-1 on the surface of the activated CTL. Lysis of bystanders is viewed as acceptable "collateral" damage, but the persistent presence of activated CTL could result in immunopathologies involving functional Fas-expressing tissues.

Recognising out-of-hospital cardiac arrest during emergency calls increases bystander cardiopulmonary resuscitation and survival.

PubMed

Viereck, Søren; Møller, Thea Palsgaard; Ersbøll, Annette Kjær; Bækgaard, Josefine Stokholm; Claesson, Andreas; Hollenberg, Jacob; Folke, Fredrik; Lippert, Freddy K

2017-06-01

Initiation of early bystander cardiopulmonary resuscitation (CPR) depends on bystanders' or medical dispatchers' recognition of out-of-hospital cardiac arrest (OHCA). The primary aim of our study was to investigate if OHCA recognition during the emergency call was associated with bystander CPR, return of spontaneous circulation (ROSC), and 30-day survival. Our secondary aim was to identify patient-, setting-, and dispatcher-related predictors of OHCA recognition. We performed an observational study of all OHCA patients' emergency calls in the Capital Region of Denmark from 01/01/2013-31/12/2013. OHCAs were collected from the Danish Cardiac Arrest Registry and the Mobile Critical Care Unit database. Emergency call recordings were identified and evaluated. Multivariable logistic regression analyses were applied to all OHCAs and witnessed OHCAs only to analyse the association between OHCA recognition and bystander CPR, ROSC, and 30-day survival. Univariable logistic regression analyses were applied to identify predictors of OHCA recognition. We included 779 emergency calls in the analyses. During the emergency calls, 70.1% (n=534) of OHCAs were recognised; OHCA recognition was positively associated with bystander CPR (odds ratio [OR]=7.84, 95% confidence interval [CI]: 5.10-12.05) in all OHCAs; and ROSC (OR=1.86, 95% CI: 1.13-3.06) and 30-day survival (OR=2.80, 95% CI: 1.58-4.96) in witnessed OHCA. Predictors of OHCA recognition were addressing breathing (OR=1.76, 95% CI: 1.17-2.66) and callers located by the patient's side (OR=2.16, 95% CI: 1.46-3.19). Recognition of OHCA during emergency calls was positively associated with the provision of bystander CPR, ROSC, and 30-day survival in witnessed OHCA. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Validity for an integrated laboratory analogue of sexual aggression and bystander intervention.

PubMed

Parrott, Dominic J; Tharp, Andra Teten; Swartout, Kevin M; Miller, Cameron A; Hall, Gordon C Nagayama; George, William H

2012-01-01

This study sought to develop and validate an integrated laboratory paradigm of sexual aggression and bystander intervention. Participants were a diverse community sample (54% African American) of heterosexual males (N = 156) between 21 and 35 years of age who were recruited to complete the study with a male friend and an ostensibly single, heterosexual female who reported a strong dislike of sexual content in the media. Participants viewed a sexually explicit or nonsexually explicit film clip as part of contrived media rating task and made individual choices of which film clip to show the female confederate. Immediately thereafter, participants were required to reach consensus on a group decision of which film clip to show the female confederate. Subjecting a target to an unwanted experience with a sexual connotation was operationalized as selection of the sexually explicit video, whereas successful bystander intervention was operationalized as the event of one partner individually selecting the sexually explicit video but then selecting the nonsexually explicit video for the group choice. Results demonstrated that a 1-year history of sexual aggression and endorsement of pertinent misogynistic attitudes significantly predicted selection of the sexually-explicit video. In addition, bystander efficacy significantly predicted men's successful prevention of their male peer's intent to show the female confederate a sexually explicit video. Discussion focused on how these data inform future research and bystander intervention programming for sexual aggression. © 2012 Wiley Periodicals, Inc.

Bystander capability to activate speaker function for continuous dispatcher assisted CPR in case of suspected cardiac arrest.

PubMed

Steensberg, Alvilda T; Eriksen, Mette M; Andersen, Lars B; Hendriksen, Ole M; Larsen, Heinrich D; Laier, Gunnar H; Thougaard, Thomas

2017-06-01

The European Resuscitation Council Guidelines 2015 recommend bystanders to activate their mobile phone speaker function, if possible, in case of suspected cardiac arrest. This is to facilitate continuous dialogue with the dispatcher including (if required) cardiopulmonary resuscitation instructions. The aim of this study was to measure the bystander capability to activate speaker function in case of suspected cardiac arrest. In 87days, a systematic prospective registration of bystander capability to activate the speaker function, when cardiac arrest was suspected, was performed. For those asked, "can you activate your mobile phone's speaker function", audio recordings were examined and categorized into groups according to the bystanders capability to activate speaker function on their own initiative, without instructions, or with instructions from the emergency medical dispatcher. Time delay was measured, in seconds, for the bystanders without pre-activated speaker function. 42.0% (58) was able to activate the speaker function without instructions, 2.9% (4) with instructions, 18.1% (25) on own initiative and 37.0% (51) were unable to activate the speaker function. The median time to activate speaker function was 19s and 8s, with and without instructions, respectively. Dispatcher assisted cardiopulmonary resuscitation with activated speaker function, in cases of suspected cardiac arrest, allows for continuous dialogue between the emergency medical dispatcher and the bystander. In this study, we found a 63.0% success rate of activating the speaker function in such situations. Copyright © 2017 Elsevier B.V. All rights reserved.

Workplace mobbing and bystanders' helping behaviour towards victims: the role of gender, perceived responsibility and anticipated stigma by association.

PubMed

Mulder, Roelie; Pouwelse, Mieneke; Lodewijkx, Hein; Bolman, Catherine

2014-08-01

We examined victims' perceived responsibility and bystanders' anticipated risk of being victimized themselves when others associate them with the victim (stigma by association, SBA) as possible antecedents of bystanders' helping behaviour towards a victim of workplace mobbing, and explored the effects of gender. Guided by the attribution model of social conduct (Weiner, 2006), a 2 × 2 vignette experiment was conducted. Participants were Dutch regional government employees (N = 161). Path analyses generally supported the hypotheses, but showed different results for women and men. In the strong (Vs. weak) responsibility condition, women reported less sympathy and more anger and men only more anger, which resulted in lower helping intention. Additionally, for men the results showed an unexpected direct positive effect of responsibility on helping intention. Furthermore, in the strong SBA condition, women and men reported more fear and men, unexpectedly, more anger. Consequently, helping intention decreased. The findings on gender are discussed in the context of social role theory, gender and emotion. Our findings suggest that to prevent and tackle mobbing, organizations and professionals should be aware of the attributional and emotional processes and gender differences in bystanders' helping behaviour. © 2013 International Union of Psychological Science.

Overexpression of SKP2 Inhibits the Radiation-Induced Bystander Effects of Esophageal Carcinoma.

PubMed

Wang, Xiao-Chun; Zhang, Tie-Jun; Guo, Zi-Jian; Xiao, Chang-Yan; Ding, Xiao-Wen; Fang, Fang; Sheng, Wen-Tao; Shu, Xu; Li, Jue

2017-02-06

To investigate the effects of S-phase kinase protein 2 (SKP2) expression on the radiation induced bystander effect (RIBE) in esophageal cancer (EC) cells. Western blot was used to detect the levels of SKP2, Rad51, and Ku70 in EC cells. Positive transfection, RNAi, micronucleus (MN), and γ-H2AX focus formation assay were used to investigate the effects of SKP2 on RIBE induced by irradiated cells. We found a significant negative correlation between SKP2 expression and MN frequency ( p < 0.05) induced by RIBE. The results were further confirmed by positive transfection, RNAi, and rescue experiments.γ-H2AX focus formation assay results indicated that overexpression of SKP2 in the irradiated cells inhibited the DNA damage of RIBE cells. However, when SKP2 expression decreased in irradiated cells, the DNA damage of RIBE cells increased. Increased or decreased expression levels of SKP2 had effects on Rad51 expression under the conditions of RIBE. These results showed, for the first time, that SKP2 expression can inhibit RIBE of EC cells. The mechanism may function, at least partly, through the regulation of Rad51 in the ability to repair DNA damage.

Speculations about Bystander and Biophotons

PubMed Central

Sanders, Charles L.

2014-01-01

Mothersill and many others during the last hundred years have shown that cells and now whole animals may communicate with each other by electromagnetic waves called biophotons. This would explain the source of the bystander phenomena. These ultra-weak photons are coherent, appear to originate and concentrate in DNA of the cell nucleus and rapidly carry large amounts of data to each cell and to the trillions of other cells in the human body. The implications of such a possibility can be wonderfully important. PMID:25552952

Speculations about Bystander and Biophotons.

PubMed

Sanders, Charles L

2014-12-01

Mothersill and many others during the last hundred years have shown that cells and now whole animals may communicate with each other by electromagnetic waves called biophotons. This would explain the source of the bystander phenomena. These ultra-weak photons are coherent, appear to originate and concentrate in DNA of the cell nucleus and rapidly carry large amounts of data to each cell and to the trillions of other cells in the human body. The implications of such a possibility can be wonderfully important.

Prehospital deaths from trauma: Are injuries survivable and do bystanders help?

PubMed

Oliver, G J; Walter, D P; Redmond, A D

2017-05-01

Deaths from trauma occurring in the prehospital phase of care are typically excluded from analysis in trauma registries. A direct historical comparison with Hussain and Redmond's study on preventable prehospital trauma deaths has shown that, two decades on, the number of potentially preventable deaths remains high. Using updated methodology, we aimed to determine the current nature, injury severity and survivability of traumatic prehospital deaths and to ascertain the presence of bystanders and their role following the point of injury including the frequency of first-aid delivery. We examined the Coroners' inquest files for deaths from trauma, occurring in the prehospital phase, over a three-year period in the Cheshire and Manchester (City), subsequently referred to as Manchester, Coronial jurisdictions. Injuries were scored using the Abbreviated-Injury-Scale (AIS-2008), Injury Severity Score (ISS) calculated and probability of survival estimated using the Trauma Audit and Research Network's outcome prediction model. One hundred and seventy-eight deaths were included in the study (one hundred and thirty-four Cheshire, forty-four Manchester). The World Health Organisation's recommendations consider those with a probability of survival between 25-50% as potentially preventable and those above 50% as preventable. The median ISS was 29 (Cheshire) and 27.5 (Manchester) with sixty-two (46%) and twenty-six (59%) respectively having a probability of survival in the potentially preventable and preventable ranges. Bystander presence during or immediately after the point of injury was 45% (Cheshire) and 39% (Manchester). Bystander intervention of any kind was 25% and 30% respectively. Excluding those found dead and those with a probability of survival less than 25%, bystanders were present immediately after the point of injury or "within minutes" in thirty-three of thirty-five (94%) Cheshire and ten of twelve (83%) Manchester. First aid of any form was attempted in fourteen

Analysis of bystander CPR quality during out-of-hospital cardiac arrest using data derived from automated external defibrillators.

PubMed

Fernando, Shannon M; Vaillancourt, Christian; Morrow, Stanley; Stiell, Ian G

2018-07-01

Little is known regarding the quality of cardiopulmonary resuscitation (CPR) performed by bystanders in out-of-hospital cardiac arrest (OHCA). We sought to determine quality of bystander CPR provided during OHCA using CPR quality data stored by Automated External Defibrillators (AEDs). We used the Resuscitation Outcomes Consortium database to identify OHCA cases of presumed cardiac etiology where an AED was utilized. We then matched AED data to each case identified. AED data was analyzed using manufacturer software in order to determine overall measures of bystander CPR quality, changes in bystander CPR quality over time, and adherence to existing 2010 Resuscitation Quality Guidelines. 100 cases of OHCA of presumed cardiac etiology involving bystander CPR and with corresponding AED data. Mean age was 62.3 years, and 75% were male. Bystanders demonstrated high-quality CPR over all minutes of resuscitation, with a chest compression fraction of 76%, a compression depth of 5.3 cm, and a compression rate of 111.2 compressions/min. Mean perishock pause was 26.8 s. Adherence rates to 2010 Resuscitation Guidelines for compression rate and depth were found to be 66% and 55%, respectively. CPR quality was lowest in the first minute, resulting from increased delay to rhythm analysis (mean 40.7 s). In cases involving shock delivery, latency from initiation of AED to shock delivery was 59.2 s. We found that bystanders perform high-quality CPR, with strong adherence rates to existing Resuscitation Guidelines. High-quality CPR is maintained over the first five minutes of resuscitation, but was lowest in the first minute. Copyright © 2018 Elsevier B.V. All rights reserved.

Host and Viral Factors in HIV-Mediated Bystander Apoptosis

PubMed Central

Garg, Himanshu; Joshi, Anjali

2017-01-01

Human immunodeficiency virus (HIV) infections lead to a progressive loss of CD4 T cells primarily via the process of apoptosis. With a limited number of infected cells and vastly disproportionate apoptosis in HIV infected patients, it is believed that apoptosis of uninfected bystander cells plays a significant role in this process. Disease progression in HIV infected individuals is highly variable suggesting that both host and viral factors may influence HIV mediated apoptosis. Amongst the viral factors, the role of Envelope (Env) glycoprotein in bystander apoptosis is well documented. Recent evidence on the variability in apoptosis induction by primary patient derived Envs underscores the role of Env glycoprotein in HIV disease. Amongst the host factors, the role of C-C Chemokine Receptor type 5 (CCR5), a coreceptor for HIV Env, is also becoming increasingly evident. Polymorphisms in the CCR5 gene and promoter affect CCR5 cell surface expression and correlate with both apoptosis and CD4 loss. Finally, chronic immune activation in HIV infections induces multiple defects in the immune system and has recently been shown to accelerate HIV Env mediated CD4 apoptosis. Consequently, those factors that affect CCR5 expression and/or immune activation in turn indirectly regulate HIV mediated apoptosis making this phenomenon both complex and multifactorial. This review explores the complex role of various host and viral factors in determining HIV mediated bystander apoptosis. PMID:28829402

Bystanders' Supportive and Passive Responses to Cyberaggression

ERIC Educational Resources Information Center

Machackova, Hana; Dedkova, Lenka; Sevcikova, Anna; Cerna, Alena

2018-01-01

Bystanders in cyberaggression can support the victim, join the aggressor, or remain passive. We examined how supportive and passive adolescent Czech cyberbystanders (N = 443, ages 12-18) differ in terms of individual characteristics, emotional responses, and contextual factors. The most substantial distinguishing factor between the two groups…

Negative Bystander Behavior in Bullying Dynamics: Assessing the Impact of Social Capital Deprivation and Anti-social Capital.

PubMed

Evans, Caroline B R; Smokowski, Paul R

2017-02-01

Bystanders witness bullying, but are not directly involved as a bully or victim; however, they often engage in negative bystander behavior. This study examines how social capital deprivation and anti-social capital are associated with the likelihood of engaging in negative bystander behavior in a sample (N = 5752) of racially/ethnically diverse rural youth. Data were collected using an online, youth self-report; the current study uses cross sectional data. Following multiple imputation, a binary logistic regression with robust standard errors was run. Results partially supported the hypothesis and indicated that social capital deprivation in the form of peer pressure and verbal victimization and anti-social capital in the form of delinquent friends, bullying perpetration, verbal perpetration, and physical perpetration were significantly associated with an increased likelihood of engaging in negative bystander behavior. Findings highlight the importance of establishing sources of positive social support for disenfranchised youth.

To act or not to act, that is the question? Barriers and facilitators of bystander intervention.

PubMed

Bennett, Sidney; Banyard, Victoria L; Garnhart, Lydia

2014-02-01

A promising line of inquiry in sexual violence prevention involves training potential bystanders to intervene in situations where there is risk for violence. Theories of bystander intervention often discuss barriers to helping behavior, but there has been little empirical inquiry into this question. We will present findings of a study of both barriers and facilitators of helping behavior in the context of sexual violence among first-semester college students. Two hundred and forty-two first year college students completed surveys during their first year of college. Measures included assessment of bystander behavior, perceived barriers to helping, as well as a variety of other variables identified in the literature as key correlates of helping. Quantitative and qualitative analyses were used to (a) describe barriers and facilitators of helping, (b) examine the relationship between barriers and self-reports of helping, and (c) model individual differences in helping behavior. In quantitative analyses, barriers, as assessed in this study, were better predictors of helping behavior directed at strangers than helping of friends. Results suggested that open-ended responses about the facilitators and barriers to helping for sexual violence map well onto social-psychological models of bystander behavior, and that greater prosocial tendencies, an intrapersonal variable, increase actual helping behavior. A more specific understanding of what promotes and hinders helping can be used to enhance prevention education efforts focused on increasing helpful bystander actions.

Exploring the Impact of Bullying on Young Bystanders

ERIC Educational Resources Information Center

Hutchinson, Matthew

2012-01-01

This study aimed to explore peer bullying events in schools by using Interpretative Phenomenological Analysis (IPA) to consider the experiences of young bystanders: the perceptions and understandings of students who had witnessed bullying. Participants were aged 12-13 and attended two neighbouring secondary schools in the UK. Four themes were…

A Randomized Controlled Study Evaluating a Brief, Bystander Bullying Intervention with Junior High School Students

ERIC Educational Resources Information Center

Midgett, Aida; Doumas, Diana; Trull, Rhiannon; Johnston, April D.

2017-01-01

A randomized controlled study evaluated a brief, bystander bullying intervention for junior high school students. Students in both groups reported an increase in knowledge and confidence to act as defenders and to utilize strategies to intervene on behalf of victims of bullying. Findings suggest possible carry-over effects from the intervention…

Lay Bystanders' Perspectives on What Facilitates Cardiopulmonary Resuscitation and Use of Automated External Defibrillators in Real Cardiac Arrests.

PubMed

Malta Hansen, Carolina; Rosenkranz, Simone Mørk; Folke, Fredrik; Zinckernagel, Line; Tjørnhøj-Thomsen, Tine; Torp-Pedersen, Christian; Sondergaard, Kathrine B; Nichol, Graham; Hulvej Rod, Morten

2017-03-13

Many patients who suffer an out-of-hospital cardiac arrest will fail to receive bystander intervention (cardiopulmonary resuscitation [CPR] or defibrillation) despite widespread CPR training and the dissemination of automated external defibrillators (AEDs). We sought to investigate what factors encourage lay bystanders to initiate CPR and AED use in a cohort of bystanders previously trained in CPR techniques who were present at an out-of-hospital cardiac arrest. One-hundred and twenty-eight semistructured qualitative interviews with CPR-trained lay bystanders to consecutive out-of-hospital cardiac arrest, where an AED was present were conducted (from January 2012 to April 2015, in Denmark). Purposive maximum variation sampling was used to establish the breadth of the bystander perspective. Twenty-six of the 128 interviews were chosen for further in-depth analyses, until data saturation. We used cross-sectional indexing (using software), and inductive in-depth thematic analyses, to identify those factors that facilitated CPR and AED use. In addition to prior hands-on CPR training, the following were described as facilitators: prior knowledge that intervention is crucial in improving survival, cannot cause substantial harm, and that the AED will provide guidance through CPR; prior hands-on training in AED use; during CPR performance, teamwork (ie, support), using the AED voice prompt and a ventilation mask, as well as demonstrating leadership and feeling a moral obligation to act. Several factors other than previous hands-on CPR training facilitate lay bystander instigation of CPR and AED use. The recognition and modification of these factors may increase lay bystander CPR rates and patient survival following an out-of-hospital cardiac arrest. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Real-time Molecular Study of Bystander Effects of Low dose Low LET radiation Using Living Cell Imaging and Nanoparticale Optics

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

Natarajan, Mohan; Xu, Nancy R; Mohan, Sumathy

2013-06-03

In this study two novel approaches are proposed to investigate precisely the low dose low LET radiation damage and its effect on bystander cells in real time. First, a flow shear model system, which would provide us a near in vivo situation where endothelial cells in the presence of extra cellular matrix experiencing continuous flow shear stress, will be used. Endothelial cells on matri-gel (simulated extra cellular matrix) will be subjected to physiological flow shear (that occurs in normal blood vessels). Second, a unique tool (Single nano particle/single live cell/single molecule microscopy and spectroscopy; Figure A) will be used tomore » track the molecular trafficking by single live cell imaging. Single molecule chemical microscopy allows one to single out and study rare events that otherwise might be lost in assembled average measurement, and monitor many target single molecules simultaneously in real-time. Multi color single novel metal nanoparticle probes allow one to prepare multicolor probes (Figure B) to monitor many single components (events) simultaneously and perform multi-complex analysis in real-time. These nano-particles resist to photo bleaching and hence serve as probes for unlimited timeframe of analysis. Single live cell microscopy allows one to image many single cells simultaneously in real-time. With the combination of these unique tools, we will be able to study under near-physiological conditions the cellular and sub-cellular responses (even subtle changes at one molecule level) to low and very low doses of low LET radiation in real time (milli-second or nano-second) at sub-10 nanometer spatial resolution. This would allow us to precisely identify, at least in part, the molecular mediators that are responsible of radiation damage in the irradiated cells and the mediators that are responsible for initiating the signaling in the neighboring cells. Endothelial cells subjected to flow shear (2 dynes/cm2 or 16 dynes/cm2) and exposed to 0.1, 1

Vaccination Expands Antigen-Specific CD4+ Memory T Cells and Mobilizes Bystander Central Memory T Cells

PubMed Central

Li Causi, Eleonora; Parikh, Suraj C.; Chudley, Lindsey; Layfield, David M.; Ottensmeier, Christian H.; Stevenson, Freda K.; Di Genova, Gianfranco

2015-01-01

CD4+ T helper memory (Thmem) cells influence both natural and vaccine-boosted immunity, but mechanisms for their maintenance remain unclear. Pro-survival signals from the common gamma-chain cytokines, in particular IL-7, appear important. Previously we showed in healthy volunteers that a booster vaccination with tetanus toxoid (TT) expanded peripheral blood TT-specific Thmem cells as expected, but was accompanied by parallel increase of Thmem cells specific for two unrelated and non cross-reactive common recall antigens. Here, in a new cohort of healthy human subjects, we compare blood vaccine-specific and bystander Thmem cells in terms of differentiation stage, function, activation and proliferative status. Both responses peaked 1 week post-vaccination. Vaccine-specific cytokine-producing Thmem cells were predominantly effector memory, whereas bystander cells were mainly of central memory phenotype. Importantly, TT-specific Thmem cells were activated (CD38High HLA-DR+), cycling or recently divided (Ki-67+), and apparently vulnerable to death (IL-7RαLow and Bcl-2 Low). In contrast, bystander Thmem cells were resting (CD38Low HLA-DR- Ki-67-) with high expression of IL-7Rα and Bcl-2. These findings allow a clear distinction between vaccine-specific and bystander Thmem cells, suggesting the latter do not derive from recent proliferation but from cells mobilized from as yet undefined reservoirs. Furthermore, they reveal the interdependent dynamics of specific and bystander T-cell responses which will inform assessments of responses to vaccines. PMID:26332995

Musical agency reduces perceived exertion during strenuous physical performance

PubMed Central

Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc

2013-01-01

Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting. PMID:24127588

Musical agency reduces perceived exertion during strenuous physical performance.

PubMed

Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc

2013-10-29

Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting.

Increased frequency of spontaneous neoplastic transformation in progeny of bystander cells from cultures exposed to densely ionizing radiation.

PubMed

Buonanno, Manuela; de Toledo, Sonia M; Azzam, Edouard I

2011-01-01

An increased risk of carcinogenesis caused by exposure to space radiation during prolonged space travel is a limiting factor for human space exploration. Typically, astronauts are exposed to low fluences of ionizing particles that target only a few cells in a tissue at any one time. The propagation of stressful effects from irradiated to neighboring bystander cells and their transmission to progeny cells would be of importance in estimates of the health risks of exposure to space radiation. With relevance to the risk of carcinogenesis, we investigated, in model C3H 10T½ mouse embryo fibroblasts (MEFs), modulation of the spontaneous frequency of neoplastic transformation in the progeny of bystander MEFs that had been in co-culture 10 population doublings earlier with MEFs exposed to moderate doses of densely ionizing iron ions (1 GeV/nucleon) or sparsely ionizing protons (1 GeV). An increase (P<0.05) in neoplastic transformation frequency, likely mediated by intercellular communication through gap junctions, was observed in the progeny of bystander cells that had been in co-culture with cells irradiated with iron ions, but not with protons.

Incoming College Students' Bystander Behaviors to Prevent Sexual Violence

ERIC Educational Resources Information Center

McMahon, Sarah; Banyard, Victoria L.; McMahon, Sheila M.

2015-01-01

Evaluations of bystander intervention education programs demonstrate that this approach results in students' increased willingness to intervene in prosocial ways to prevent sexual violence (e.g., Moynihan, Banyard, Arnold, Eckstein, & Stapleton, 2010). These programs often focus on first-year college students, though theories and research on…

Association between bystander cardiopulmonary resuscitation and redeemed prescriptions for antidepressants and anxiolytics in out-of-hospital cardiac arrest survivors.

PubMed

Bundgaard, Kristian; Hansen, Steen M; Mortensen, Rikke Nørmark; Wissenberg, Mads; Hansen, Malta; Lippert, Freddy; Gislason, Gunnar; Køber, Lars; Nielsen, Jimmi; Torp-Pedersen, Christian; Rasmussen, Bodil Steen; Kragholm, Kristian

2017-06-01

This study aimed to examine rates of redeemed prescriptions of antidepressants and anxiolytics, used as markers for cerebral dysfunction in out-of-hospital cardiac arrest (OHCA) survivors, and examine the association between bystander CPR and these psychoactive drugs. We included all 30-day survivors of OHCA in Denmark between 2001 and 2011, who had not redeemed prescriptions for antidepressants or anxiolytics in the last six months prior to OHCA. Main outcome measures were redeemed prescriptions of antidepressants and anxiolytics within one year after OHCA. Among 2,001 30-day survivors, 174 (8.6% died and 12.0% redeemed a first prescription for an antidepressant and 8.2% for an anxiolytic drug within one year after arrest. The corresponding frequencies for redeemed prescribed drugs among age- and sex-matched population controls were 7.5% and 5.2%, respectively. Among survivors who received bystander CPR, prescriptions for antidepressants and anxiolytics were redeemed in 11.1% [95% CI 9.2-13.3%] and 6.3% [95% CI 4.9-8.0%] of the cases, respectively, versus 17.2% [95% CI 13.9-21.1%] and 13.4% [95% CI 10.5-17.0%], respectively, among patients who had not received bystander CPR. Adjusted for age, sex, year of arrest, comorbidity, witnessed status and socioeconomic status, bystander CPR was associated with significant reductions in redeemed prescriptions for antidepressants, Hazard Ratio (HR) 0.71 [95% CI 0.52-0.98], P=0.031; and anxiolytics, HR 0.55 [95% CI 0.38-0.81], P=0.002. Relative to no bystander CPR, redeemed prescriptions for antidepressants and anxiolytics were significantly lower among 30-day survivors of OHCA who received bystander CPR, suggesting a cerebral dysfunction-lowering potential of bystander CPR. Copyright © 2017 Elsevier B.V. All rights reserved.

Prior Acute Mental Exertion in Exercise and Sport

PubMed Central

Silva-Júnior, Fernando Lopes e; Emanuel, Patrick; Sousa, Jordan; Silva, Matheus; Teixeira, Silmar; Pires, Flávio Oliveira; Machado, Sérgio; Arias-Carrion, Oscar

2016-01-01

Introduction: Mental exertion is a psychophysiological state caused by sustained and prolonged cognitive activity. The understanding of the possible effects of acute mental exertion on physical performance, and their physiological and psychological responses are of great importance for the performance of different occupations, such as military, construction workers, athletes (professional or recreational) or simply practicing regular exercise, since these occupations often combine physical and mental tasks while performing their activities. However, the effects of implementation of a cognitive task on responses to aerobic exercise and sports are poorly understood. Our narrative review aims to provide information on the current research related to the effects of prior acute mental fatigue on physical performance and their physiological and psychological responses associated with exercise and sports. Methods: The literature search was conducted using the databases PubMed, ISI Web of Knowledge and PsycInfo using the following terms and their combinations: “mental exertion”, “mental fatigue”, “mental fatigue and performance”, “mental exertion and sports” “mental exertion and exercise”. Results: We concluded that prior acute mental exertion affects effectively the physiological and psychophysiological responses during the cognitive task, and performance in exercise. Conclusion: Additional studies involving prior acute mental exertion, exercise/sports and physical performance still need to be carried out in order to analyze the physiological, psychophysiological and neurophysiological responses subsequently to acute mental exertion in order to identify cardiovascular factors, psychological, neuropsychological associates. PMID:27867415

Personal Responsibility and Behavioral Disengagement in Innocent Bystanders during Classroom Management Events: The Moderating Effect of Teacher Aggressive Tendencies

ERIC Educational Resources Information Center

Montuoro, Paul; Lewis, Ramon

2018-01-01

Recent studies have shown that student behavioral engagement is malleable. For example, these studies have reported that students who feel emotionally supported by their teachers experience higher levels of behavioral engagement. The authors contributed to this research by investigating behavioral disengagement among innocent bystanders during…

Identifying barriers to the provision of bystander cardiopulmonary resuscitation (CPR) in high-risk regions: a qualitative review of emergency calls.

PubMed

Case, Rosalind; Cartledge, Susie; Siedenburg, Josine; Smith, Karen; Straney, Lahn; Barger, Bill; Finn, Judith; Bray, Janet E

2018-06-01

Understanding regional variation in bystander cardiopulmonary resuscitation (CPR) is important to improving out-of-hospital cardiac arrest (OHCA) survival. In this study we aimed to identify barriers to providing bystander CPR in regions with low rates of bystander CPR and where OHCA was recognised in the emergency call. We retrospectively reviewed emergency calls for adults in regions of low bystander CPR in the Australian state of Victoria. Included calls were those where OHCA was identified during the call but no bystander CPR was given. A thematic content analysis was independently conducted by two investigators. Saturation of themes was reached after listening to 139 calls. Calls progressed to the point of compression instructions before EMS arrival in only 26 (18.7%) of cases. Three types of barriers were identified: procedural barriers (time lost due to language barriers and communication issues; telephone problems), CPR knowledge (skill deficits; perceived benefit) and personal factors (physical frailty or disability; patient position; emotional factors). A range of factors are associated with barriers to delivering bystander CPR even in the presence of dispatcher instructions -some of which are modifiable. To overcome these barriers in high-risk regions, targeted public education needs to provide information about what occurs in an emergency call, how to recognise an OHCA and to improve CPR knowledge and skills. Copyright © 2018. Published by Elsevier B.V.

Changing attitudes about being a bystander to violence: translating an in-person sexual violence prevention program to a new campus.

PubMed

Cares, Alison C; Banyard, Victoria L; Moynihan, Mary M; Williams, Linda M; Potter, Sharyn J; Stapleton, Jane G

2015-02-01

Bystander approaches to reducing sexual violence train community members in prosocial roles to interrupt situations with risk of sexual violence and be supportive community allies after an assault. This study employs a true experimental design to evaluate the effectiveness of Bringing in the Bystander™ through 1-year post-implementation with first-year students from two universities (one rural, primarily residential; one urban, heavily commuter). We found significant change in bystander attitudes for male and female student program participants compared with the control group on both campuses, although the pattern of change depended on the combination of gender and campus. © The Author(s) 2014.

Recommendations in dispatcher-assisted bystander resuscitation from emergency call center.

PubMed

García del Águila, J; López-Messa, J; Rosell-Ortiz, F; de Elías Hernández, R; Martínez del Valle, M; Sánchez-Santos, L; López-Herce, J; Cerdà-Vila, M; Roza-Alonso, C L; Bernardez-Otero, M

2015-01-01

Dispatch-assisted bystander cardiopulmonary resuscitation in out-of-hospital cardiac arrest has been shown as an effective measure to improve the survival of this process. The development of a unified protocol for all dispatch centers of the different emergency medical services can be a first step towards this goal in our environment. The process of developing a recommendations document and the realization of posters of dispatch-assisted cardiopulmonary resuscitation, agreed by different actors and promoted by the Spanish Resuscitation Council, is presented. Copyright © 2015 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

A Qualitative Exploration of Cyber-Bystanders and Moral Engagement

ERIC Educational Resources Information Center

Price, Deborah; Green, Deborah; Spears, Barbara; Scrimgeour, Margaret; Barnes, Alan; Geer, Ruth; Johnson, Bruce

2014-01-01

Studies have found that moral disengagement plays a significant role in the continuation of bullying situations (Bonanno, 2005); however, the moral stance of cyber-bystanders--those who witness online bullying--is not yet clear. While research into traditional face-to-face bullying reported that peers would probably or certainly intervene to…

Examining Effects of Physical Exertion on the Dynamic Visual Acuity Test in Collegiate Athletes.

PubMed

Patterson, Jessie N; Murphy, Anna M; Honaker, Julie A

2017-01-01

Acute symptoms of dizziness and/or imbalance commonly experienced in athletes postconcussion are speculated to arise from dysfunction at multiple levels (i.e., inner ear or central vestibular system) to appropriately integrate afferent sensory information. Disruption along any pathway of the balance system can result in symptoms of dizziness, decreased postural control function (vestibulospinal reflex), and reduced vestibulo-ocular reflex function. This may also lead to decreased gaze stability with movements of the head and may account for symptoms of blurred vision or diplopia reported in almost half of athletes sustaining a concussion. Current concussion position statements include measures of postural control to examine changes to the balance system postconcussion. The Balance Error Scoring System (BESS) is a commonly used low-cost postural control measure for concussion assessment. Although this is a widely used measure for documenting balance function on both immediate (sideline) and recovery monitoring, the BESS has been shown to be affected by physical exertion. Therefore, the BESS may not be the most efficient means of examining functional changes to the balance system immediately after head injury. Dynamic Visual Acuity Test (DVAT) has been found to effectively evaluate and monitor changes to the gaze stability system postinjury. Thus, DVAT may be an additional measure in the concussion assessment battery, as well as an alternative for more immediate sideline assessment to help make objective return-to-play decisions. The aim of the study was to determine the effects of physical exertion on a clinical vestibular assessment, the DVAT, in collegiate athletes, as a first step in defining the role of this measure in the concussion assessment battery. Cross-sectional, repeated-measures design. Twenty-eight healthy collegiate athletes (20 males, 8 females; age = 20.25 ± 1.46 yr, range = 18-25 yr) volunteered to participate in the study. Participants were

A Longitudinal Study of the Associations between Moral Disengagement and Active Defending versus Passive Bystanding during Bullying Situations

ERIC Educational Resources Information Center

Doramajian, Caroline; Bukowski, William M.

2015-01-01

This study investigated the prospective association between moral disengagement and bystander behaviors in bullying situations, including both defending and passive bystanding. A diverse sample of Canadian school children (N = 130; 68 boys and 62 girls; mean age = 11.36 years) participated in a three-wave longitudinal study over a 4-month period.…

Absent bystanders and cognitive dissonance: a comment on Timmins & de Vries.

PubMed

Paley, John

2015-04-01

Timmins & de Vries are more sympathetic to my editorial than other critics, but they take issue with the details. They doubt whether the bystander phenomenon applies to Mid Staffs nurses; they believe that cognitive dissonance is a better explanation of why nurses fail to behave compassionately; and they think that I am 'perhaps a bit rash' to conclude that 'teaching compassion may be fruitless'. In this comment, I discuss all three points. I suggest that the bystander phenomenon is irrelevant; that Timmins & de Vries give an incomplete account of cognitive dissonance; and that it isn't rash to propose that educating nurses 'for compassion' is a red herring. Additionally, I comment on the idea that I wish to mount a 'defence of healthcare staff'. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gata3 hypermethylation and Foxp3 hypomethylation are associated with sustained protection and bystander effect following epicutaneous immunotherapy in peanut-sensitized mice.

PubMed

Mondoulet, Lucie; Dioszeghy, Vincent; Busato, Florence; Plaquet, Camille; Dhelft, Véronique; Bethune, Kevin; Leclere, Laurence; Daviaud, Christian; Ligouis, Mélanie; Sampson, Hugh; Dupont, Christophe; Tost, Jörg

2018-05-19

Epicutaneous immunotherapy (EPIT) is a promising method for treating food allergies. In animal models, EPIT induces sustained unresponsiveness and prevents further sensitization mediated by Tregs. Here, we elucidate the mechanisms underlying the therapeutic effect of EPIT, by characterizing the kinetics of DNA methylation changes in sorted cells from spleen and blood and by evaluating its persistence and bystander effect compared to oral immunotherapy (OIT). BALB/c mice orally sensitized to peanut proteins (PPE) were treated by EPIT using a PPE-patch or by PPE-OIT. Another set of peanut-sensitized mice treated by EPIT or OIT were sacrificed following a protocol of sensitization to OVA. DNA methylation was analysed during immunotherapy and 8 weeks after the end of treatment in sorted cells from spleen and blood by pyrosequencing. Humoral and cellular responses were measured during and after immunotherapy. Analyses showed a significant hypermethylation of the Gata3 promoter detectable only in Th2 cells for EPIT from the 4 th week and a significant hypomethylation of the Foxp3 promoter in CD62L + Tregs, which was sustained only for EPIT. In addition, mice treated with EPIT were protected from subsequent sensitization and maintained the epigenetic signature characteristic for EPIT. Our study demonstrates that EPIT leads to a unique and stable epigenetic signature in specific T cell compartments with down regulation of Th2 key regulators and upregulation of Treg transcription factors, likely explaining the sustainability of protection and the observed bystander effect. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

How Community and Peer Perceptions Promote College Students' Pro-Social Bystander Actions to Prevent Sexual Violence.

PubMed

Banyard, Victoria L; Rizzo, Andrew J; Bencosme, Yamilex; Cares, Alison C; Moynihan, Mary M

2018-06-01

The prevalence of sexual violence crimes on U.S. college campuses is prompting institutions of higher education to increasingly invest in centers to support survivors and programs to prevent the violence before it happens. Understanding bystanders to sexual violence and what may motivate them to step in and help is a promising prevention strategy. The purpose of this study was to understand how potential active bystanders' (first-year college students) perceptions of community (including a sense of one's influence in the community and positive peer norms for helping) and individual beliefs about self (including sense of responsibility and self-efficacy) affect their self-reports of performing bystander behavior to address sexual violence risks. Participants were 948 students at two different universities (one a rural, primarily residential campus and the other an urban, mostly commuter campus) in the northeastern United States. Regression and path analysis quantitative results suggest that individual-level characteristics may mediate some of the impact that community-level norms and perceptions have on bystander outcomes, explaining some of the mixed findings in previous research. Prevention strategies should work to change community norms and perceptions of mattering and perceptions of community influence in addition to the more traditional focus on individual-level violence specific attitudes.

Addressing sexual and relationship violence in the LGBT community using a bystander framework.

PubMed

Potter, Sharyn J; Fountain, Kim; Stapleton, Jane G

2012-01-01

Sexual and relationship violence are two major public health issues that affect an alarming number of undergraduate students. As a result, many colleges and universities have protocols to serve victims of these forms of violence. Despite federal legislation stating that all students should have equitable experiences, current protocols and programs focus primarily on heterosexual students. College student victims of sexual and relationship violence who identify as lesbian, gay, bisexual, or transgender can face particular challenges, including disclosure of their sexual and gender orientations, and revictimization when seeking services. In recent years an increasing number of campuses have adopted bystander prevention strategies to address sexual and relationship violence. These strategies seek to engage community members in the prevention of sexual and relationship violence by training them to identify and safely intervene in situations where sexual or relationship violence is about to occur, is occurring, or has occurred. In this article we review published bystander prevention strategies that focus on preventing sexual and relationship violence in the campus community, and discuss how bystander strategies are addressing or can address relationship and sexual violence in the LGBT community.

The role of the bystander in the social architecture of bullying and violence in schools and communities.

PubMed

Twemlow, Stuart W; Fonagy, Peter; Sacco, Frank C

2004-12-01

The bystander is defined as an active and involved participant in the social architecture of school violence, rather than a passive witness. Bullying is redefined from a triadic (bully-victim-bystander) rather than dyadic (bully-victim) perspective. Teachers, including administrators, and students can promote or ameliorate bullying and other forms of violence when in this social role. Cases are used to illustrate this phenomenon, including one in which a teacher is murdered. Data are presented from a study of teachers' perceptions of other teachers who bully students, suggesting that bullying of students by teachers and bullying of teachers by students is a factor in the aggravation of school bullying and violence that needs to be more openly discussed. An intervention in nine elementary schools involving 3,600 students is outlined to illustrate how a focus on reflective mentalizing and awareness of the importance of the helpful bystander role can promote a peaceful school-learning environment for students and teachers. The paper concludes with an outline for research into how communities and schools adopt bystanding roles when faced with complex problems like youth violence, and how they may avoid facing the problems by blaming law enforcement and educators.

The Role of Self-Efficacy for Bystander Helping Behaviors in Risky Alcohol Situations

PubMed Central

Krieger, Heather; Serrano, Surizaday; Neighbors, Clayton

2017-01-01

We examined the role of self-efficacy in preventing bystander inaction in dangerous alcohol situations. Participants (N = 504) completed an online survey that assessed whether they had previously witnessed or intervened in alcohol-related emergencies, their self-efficacy for intervening, and their likelihood of intervening in the future. Previously intervening was positively associated with self-efficacy and likelihood of intervening in the future. Furthermore, self-efficacy mediated the association between previously intervening and likelihood of intervening in the future. In conclusion, self-efficacy for intervening in social situations is associated with intervening in alcohol-related emergencies and is an important factor to consider when designing bystander interventions. PMID:29097835

The Role of Self-Efficacy for Bystander Helping Behaviors in Risky Alcohol Situations.

PubMed

Krieger, Heather; Serrano, Surizaday; Neighbors, Clayton

2017-04-01

We examined the role of self-efficacy in preventing bystander inaction in dangerous alcohol situations. Participants (N = 504) completed an online survey that assessed whether they had previously witnessed or intervened in alcohol-related emergencies, their self-efficacy for intervening, and their likelihood of intervening in the future. Previously intervening was positively associated with self-efficacy and likelihood of intervening in the future. Furthermore, self-efficacy mediated the association between previously intervening and likelihood of intervening in the future. In conclusion, self-efficacy for intervening in social situations is associated with intervening in alcohol-related emergencies and is an important factor to consider when designing bystander interventions.

Standing Up for the Victim, Siding with the Bully or Standing By? Bystander Responses in Bullying Situations

ERIC Educational Resources Information Center

Poyhonen, Virpi; Juvonen, Jaana; Salmivalli, Christina

2012-01-01

In this study we examined children's self-efficacy, outcome expectations, and outcome values in relation to bystander responses in bullying situations. We proposed that beyond the effect of self-efficacy, the decision to defend the victim of bullying vs. remain passive vs. reinforce the bully depends on outcomes children expect from defending, and…

Responding to Gendered Violence among College Students: The Impact of Participant Characteristics on Direct Bystander Intervention Behavior

ERIC Educational Resources Information Center

Franklin, Cortney A.; Brady, Patrick Q.; Jurek, Alicia L.

2017-01-01

Bystander intervention has been an effective strategy for crime prevention and has been successful in the context of campus sexual assault. Less is known about the extent to which individual-level factors correlate with intervention behavior in situations of intimate partner violence (IPV) and sexual harassment. The present study used a sample of…

Rehearsing for real life: the impact of the InterACT Sexual Assault Prevention Program on self-reported likelihood of engaging in bystander interventions.

PubMed

Ahrens, Courtney E; Rich, Marc D; Ullman, Jodie B

2011-06-01

The interACT Sexual Assault Prevention Program is an interactive, skill-building performance based on the pedagogy of Augusto Boal's Theatre of the Oppressed. A longitudinal evaluation of this program compared pretest, posttest, and 3-month follow-up data from 509 university student participants. Results suggested that the interACT performance was successful in increasing participants' beliefs about the effectiveness of bystander interventions and the self-rated likelihood that participants would engage in bystander interventions in the future. Differences in both overall ratings and rates of change were noted. Implications of these results for research and practice are discussed.

Hydrocortisone Infusion Exerts Dose- and Sex-Dependent Effects on Attention to Emotional Stimuli

ERIC Educational Resources Information Center

Breitberg, Alaina; Drevets, Wayne C.; Wood, Suzanne E.; Mah, Linda; Schulkin, Jay; Sahakian, Barbara J.; Erickson, Kristine

2013-01-01

Glucocorticoid administration has been shown to exert complex effects on cognitive and emotional processing. In the current study we investigated the effects of glucocorticoid administration on attention towards emotional words, using an Affective Go/No-go task on which healthy humans have shown an attentional bias towards positive as compared to…

Defining the Focus of Attention: Effects of Attention on Perceived Exertion and Fatigue

PubMed Central

Lohse, Keith R.; Sherwood, David E.

2011-01-01

This manuscript presents two experiments designed to explore the effects of attention on perceived exertion and time to failure in a fatiguing athletic task. There were two major motivating factors for these experiments. First, there are few studies evaluating attentional focus effects in endurance tasks and, second, there is a lack of integration between studies of attentional focus as external/internal (e.g., Wulf, 2007a) compared to associative/dissociative (e.g., Stevinson and Biddle, 1998). In Experiment 1, we used a fatiguing wall-sit posture (essentially a complex, isometric task) to compare two different types of external attention with an internal focus on the position of the legs. An external focus (regardless of type) increased the time taken to failure and reduced perceived exertion. In Experiment 2, we manipulated subjects’ expectancy of fatigue to test the interaction of attention and expectancy (both top-down factors) in this highly fatiguing task. Previous theories of attention during endurance tasks have suggested that as fatigue/pain increase, bottom-up factors begin to dominate subjects’ attention. While this may be true, Experiment 2 showed that even in a highly fatiguing task, attentional strategies, and expectancies affected the time to failure and perceived exertion. PMID:22102843

Pirfenidone exerts antifibrotic effects through inhibition of GLI transcription factors.

PubMed

Didiasova, Miroslava; Singh, Rajeev; Wilhelm, Jochen; Kwapiszewska, Grazyna; Wujak, Lukasz; Zakrzewicz, Dariusz; Schaefer, Liliana; Markart, Philipp; Seeger, Werner; Lauth, Matthias; Wygrecka, Malgorzata

2017-05-01

Pirfenidone is an antifibrotic drug, recently approved for the treatment of patients with idiopathic pulmonary fibrosis (IPF). Although pirfenidone exhibits anti-inflammatory, antioxidant, and antifibrotic properties, the molecular mechanism underlying its protective effects remains unknown. Here, we link pirfenidone action with the regulation of the profibrotic hedgehog (Hh) signaling pathway. We demonstrate that pirfenidone selectively destabilizes the glioma-associated oncogene homolog (GLI)2 protein, the primary activator of Hh-mediated gene transcription. Consequently, pirfenidone decreases overall Hh pathway activity in patients with IPF and in patient-derived primary lung fibroblasts and leads to diminished levels of Hh target genes, such as GLI1, Hh receptor Patched-1, α-smooth muscle actin, and fibronectin, and to reduced cell migration and proliferation. Interestingly, Hh-triggered TGF-β1 expression potentiated Hh responsiveness of primary lung fibroblasts by elevating the available pool of glioma-associated oncogene homolog (GLI)1/GLI2, thus creating a vicious cycle of amplifying fibrotic processes. Because GLI transcription factors are not only crucial for Hh-mediated changes but are also required as mediators of TGF-β signaling, our findings suggest that pirfenidone exerts its clinically beneficial effects through dual Hh/TGF-β inhibition by targeting the GLI2 protein.-Didiasova, M., Singh, R., Wilhelm, J., Kwapiszewska, G., Wujak, L., Zakrzewicz, D., Schaefer, L., Markart, P., Seeger, W., Lauth, M., Wygrecka, M. Pirfenidone exerts antifibrotic effects through inhibition of GLI transcription factors. © FASEB.

Empowering bystanders to prevent campus violence against women: a preliminary evaluation of a poster campaign.

PubMed

Potter, Sharyn J; Moynihan, Mary M; Stapleton, Jane G; Banyard, Victoria L

2009-01-01

Researchers at a midsized public northeastern university evaluated the efficacy of a poster campaign to determine if students increase their knowledge of prosocial bystander behaviors and willingness to intervene in instances of sexual violence after viewing a series of campaign posters where student actors model appropriate bystander behaviors. During the last week of the campaign, undergraduates were invited to participate in a Web survey. The results of this preliminary evaluation indicate promising variation in the awareness of students who reported seeing the campaign compared to those who did not.

The response time threshold for predicting favourable neurological outcomes in patients with bystander-witnessed out-of-hospital cardiac arrest.

PubMed

Ono, Yuichi; Hayakawa, Mineji; Iijima, Hiroaki; Maekawa, Kunihiko; Kodate, Akira; Sadamoto, Yoshihiro; Mizugaki, Asumi; Murakami, Hiromoto; Katabami, Kenichi; Sawamura, Atsushi; Gando, Satoshi

2016-10-01

It is well established that the period of time between a call being made to emergency medical services (EMS) and the time at which the EMS arrive at the scene (i.e. the response time) affects survival outcomes in patients who experience out-of-hospital cardiac arrest (OHCA). However, the relationship between the response time and favourable neurological outcomes remains unclear. We therefore aimed to determine a response time threshold in patients with bystander-witnessed OHCA that is associated with positive neurological outcomes and to assess the relationship between the response time and neurological outcomes in patients with OHCA. This study was a retrospective, observational analysis of data from 204,277 episodes of bystander-witnessed OHCA between 2006 and 2012 in Japan. We used classification and regression trees (CARTs) and receiver operating characteristic (ROC) curve analyses to determine the threshold of response time associated with favourable neurological outcomes (Cerebral Performance Category 1 or 2) 1 month after cardiac arrest. Both CARTs and ROC analyses indicated that a threshold of 6.5min was associated with improved neurological outcomes in all bystander-witnessed OHCA events of cardiac origin. Furthermore, bystander cardiopulmonary resuscitation (CPR) prolonged the threshold of response time by 1min (up to 7.5min). The adjusted odds ratio for favourable neurological outcomes in patients with OHCA who received care within ≤6.5min was 1.935 (95% confidential interval: 1.834-2.041, P<0.001). A response time of ≤6.5min was closely associated with favourable neurological outcomes in all bystander-witnessed patients with OHCA. Bystander CPR prolonged the response time threshold by 1min. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effect of Carbohydrate Ingestion on Ratings of Perceived Exertion during a Marathon.

ERIC Educational Resources Information Center

Utter, Alan C.; Kang, Jie; Robertson, Robert J.; Nieman, David C.; Chaloupka, Edward C.; Suminski, Richard R.; Piccinni, Cristiana R.

2002-01-01

Investigated the effects of carbohydrate substrate availability on ratings of perceived exertion (RPE) and hormonal regulation during a competitive marathon. Data on marathon runners randomly assigned to receive carbohydrate or placebo indicated that those who ingested carbohydrate rather than placebo beverages were able to run at a higher…

Radiation-induced biologic bystander effect elicited in vitro by targeted radiopharmaceuticals labeled with alpha-, beta-, and auger electron-emitting radionuclides.

PubMed

Boyd, Marie; Ross, Susan C; Dorrens, Jennifer; Fullerton, Natasha E; Tan, Ker Wei; Zalutsky, Michael R; Mairs, Robert J

2006-06-01

Recent studies have shown that indirect effects of ionizing radiation may contribute significantly to the effectiveness of radiotherapy by sterilizing malignant cells that are not directly hit by the radiation. However, there have been few investigations of the importance of indirect effects in targeted radionuclide treatment. Our purpose was to compare the induction of bystander effects by external beam gamma-radiation with those resultant from exposure to 3 radiohaloanalogs of metaiodobenzylguanidine (MIBG): (131)I-MIBG (low-linear-energy-transfer [LET] beta-emitter), (123)I-MIBG (potentially high-LET Auger electron emitter), and meta-(211)At-astatobenzylguanidine ((211)At-MABG) (high-LET alpha-emitter). Two human tumor cell lines-UVW (glioma) and EJ138 (transitional cell carcinoma of bladder)-were transfected with the noradrenaline transporter (NAT) gene to enable active uptake of MIBG. Medium from cells that accumulated the radiopharmaceuticals or were treated with external beam radiation was transferred to cells that had not been exposed to radioactivity, and clonogenic survival was determined in donor and recipient cultures. Over the dose range 0-9 Gy of external beam radiation of donor cells, 2 Gy caused 30%-40% clonogenic cell kill in recipient cultures. This potency was maintained but not increased by higher dosage. In contrast, no corresponding saturation of bystander cell kill was observed after treatment with a range of activity concentrations of (131)I-MIBG, which resulted in up to 97% death of donor cells. Cellular uptake of (123)I-MIBG and (211)At-MABG induced increasing recipient cell kill up to levels that resulted in direct kill of 35%-70% of clonogens. Thereafter, the administration of higher activity concentrations of these high-LET emitters was inversely related to the kill of recipient cells. Over the range of activity concentrations examined, neither direct nor indirect kill was observed in cultures of cells not expressing the NAT and, thus

Preventing Sexual Violence Through Bystander Intervention: Attitudes, Behaviors, Missed Opportunities, and Barriers to Intervention Among Australian University Students.

PubMed

Kania, Rachel; Cale, Jesse

2018-03-01

The concept of bystander intervention is gaining popularity in universities as a mechanism to prevent sexual violence. Prior research has focused on correlates of bystanders' intentions to intervene and intervention behaviors in situations where there is a risk of sexual violence. The current study builds on this literature by exploring the nature of missed opportunities, including perceived barriers to intervention. In all, 380 Australian undergraduate university students completed an online survey. Measures included a rape myth acceptance scale, bystander intentions to intervene, actual intervention behaviors, missed opportunities for intervention, and perceived barriers for missed opportunities. Promisingly, students reported high levels of intentions to intervene in situations where there was a risk of sexual violence and reported relatively few missed opportunities to do so when these situations did occur. Intervention behaviors varied by important demographic characteristics such as gender, age, attitudes toward sexual violence, and the nature of the situation. Younger female students, with lower levels of rape myth acceptance, who had previously engaged in bystander intervention behaviors were more likely to report intentions to intervene in future risky situations, and female international students reported fewer missed opportunities for intervention. The most common barrier to intervention for identified missed opportunities was a failure to recognize situations as having a potential risk for sexual violence, and students were most likely to intervene in situations when the opportunity to help a friend in distress arose. This study provides some preliminary empirical evidence about bystander intervention against sexual violence among Australian university students, and identifies unique contexts for intervention and what current barriers to intervention may be.

Uninfected Bystander Cells Impact the Measurement of HIV-Specific Antibody-Dependent Cellular Cytotoxicity Responses

PubMed Central

Richard, Jonathan; Prévost, Jérémie; Baxter, Amy E.; Ding, Shilei; Medjahed, Halima; Delgado, Gloria G.; Brassard, Nathalie; Stürzel, Christina M.; Kirchhoff, Frank; Hahn, Beatrice H.; Parsons, Matthew S.; Kaufmann, Daniel E.; Evans, David T.

2018-01-01

ABSTRACT The conformation of the HIV-1 envelope glycoprotein (Env) substantially impacts antibody recognition and antibody-dependent cellular cytotoxicity (ADCC) responses. In the absence of the CD4 receptor at the cell surface, primary Envs sample a “closed” conformation that occludes CD4-induced (CD4i) epitopes. The virus controls CD4 expression through the actions of Nef and Vpu accessory proteins, thus protecting infected cells from ADCC responses. However, gp120 shed from infected cells can bind to CD4 present on uninfected bystander cells, sensitizing them to ADCC mediated by CD4i antibodies (Abs). Therefore, we hypothesized that these bystander cells could impact the interpretation of ADCC measurements. To investigate this, we evaluated the ability of antibodies to CD4i epitopes and broadly neutralizing Abs (bNAbs) to mediate ADCC measured by five ADCC assays commonly used in the field. Our results indicate that the uninfected bystander cells coated with gp120 are efficiently recognized by the CD4i ligands but not the bNabs. Consequently, the uninfected bystander cells substantially affect in vitro measurements made with ADCC assays that fail to identify responses against infected versus uninfected cells. Moreover, using an mRNA flow technique that detects productively infected cells, we found that the vast majority of HIV-1-infected cells in in vitro cultures or ex vivo samples from HIV-1-infected individuals are CD4 negative and therefore do not expose significant levels of CD4i epitopes. Altogether, our results indicate that ADCC assays unable to differentiate responses against infected versus uninfected cells overestimate responses mediated by CD4i ligands. PMID:29559570

The 4Rs of Aquatic Rescue: educating the public about safety and risks of bystander rescue.

PubMed

Moran, Kevin; Webber, Jonathon; Stanley, Teresa

2017-09-01

From 1980 to 2014, 87 persons drowned in New Zealand while attempting to rescue others; all incidents occurred in open water and most (80%) fatalities were male. While bystander rescue has been promoted as a way of preventing drowning, little is known about the knowledge base that informs potential rescuers. This study utilized a family water safety programme to promote a resource entitled the 4Rs of Aquatic Rescue. Participants (n = 174) completed a pre-intervention survey and were then provided with information and access to electronic resources on safe bystander rescue techniques. Most respondents (71%) had never been taught rescue techniques, and males were more confident of their rescue ability. Upon completion of the programme, significant differences were evident in respondents' understanding of rescue safety, but this did not translate to greater confidence or disposition towards performing a rescue. Ways of promoting bystander safety around water are discussed and recommendations for future studies are made.

L Particles Transmit Viral Proteins from Herpes Simplex Virus 1-Infected Mature Dendritic Cells to Uninfected Bystander Cells, Inducing CD83 Downmodulation.

PubMed

Heilingloh, Christiane S; Kummer, Mirko; Mühl-Zürbes, Petra; Drassner, Christina; Daniel, Christoph; Klewer, Monika; Steinkasserer, Alexander

2015-11-01

Mature dendritic cells (mDCs) are known as the most potent antigen-presenting cells (APCs) since they are also able to prime/induce naive T cells. Thus, mDCs play a pivotal role during the induction of antiviral immune responses. Remarkably, the cell surface molecule CD83, which was shown to have costimulatory properties, is targeted by herpes simplex virus 1 (HSV-1) for viral immune escape. Infection of mDCs with HSV-1 results in downmodulation of CD83, resulting in reduced T cell stimulation. In this study, we report that not only infected mDCs but also uninfected bystander cells in an infected culture show a significant CD83 reduction. We demonstrate that this effect is independent of phagocytosis and transmissible from infected to uninfected mDCs. The presence of specific viral proteins found in these uninfected bystander cells led to the hypothesis that viral proteins are transferred from infected to uninfected cells via L particles. These L particles are generated during lytic replication in parallel with full virions, called H particles. L particles contain viral proteins but lack the viral capsid and DNA. Therefore, these particles are not infectious but are able to transfer several viral proteins. Incubation of mDCs with L particles indeed reduced CD83 expression on uninfected bystander DCs, providing for the first time evidence that functional viral proteins are transmitted via L particles from infected mDCs to uninfected bystander cells, thereby inducing CD83 downmodulation. HSV-1 has evolved a number of strategies to evade the host's immune system. Among others, HSV-1 infection of mDCs results in an inhibited T cell activation caused by degradation of CD83. Interestingly, CD83 is lost not only from HSV-1-infected mDCs but also from uninfected bystander cells. The release of so-called L particles, which contain several viral proteins but lack capsid and DNA, during infection is a common phenomenon observed among several viruses, such as human

The effects of acclimatization on blood clotting parameters in exertional heat stress.

PubMed

Vesić, Zoran; Vukasinović-Vesić, Milica; Dincić, Dragan; Surbatović, Maja; Radaković, Sonja S

2013-07-01

Exertional heat stress is a common problem in military services. Considering the coagulation abnormalities are of major importance in development of severe heat stroke, we wanted to examine changes in hemostatic parameters in soldiers during exertional heat stress test as well as the effects of a 10-day passive or active acclimatization in a climatic chamber. A total of 40 male soldiers with high aerobic capacity performed exertional heat stress test (EHST) either in cool [20 degrees C, 16 degrees C wet bulb globe temperature (WBGT)], or hot (40 degrees C, 29 degrees C, (WBGT) environment, unacclimatized (U) or after 10 days of passive (P) or active (A) acclimatization. Physiological strain was measured by tympanic temperatures (Tty) and heart rates (HR). Platelet count (PC), antithrombin III (AT), and prothrombin time (PT) were assessed in blood samples collected before and immediately after the EHST. EHST in hot conditions induced physiological heat stress (increase in Tty and HR), with a significant increase in prothrombin time in the groups U and A. Platelet counts were significantly higher after the EHST compared to the basic levels in all the investigated groups, regardless environmental conditions and acclimatization state. Antithrombin levels were not affected by EHST whatsoever. In the trained soldiers, physiological heat stress caused mild changes in some serum parameters of blood clotting such as prothrombin time, while others such as antithrombin levels were not affected. Platelet counts were increased after EHST in all groups. A 10-day passive or active acclimatization in climatic chamber showed no effect on parameters investigated.

Do placebo expectations influence perceived exertion during physical exercise?

PubMed

Mothes, Hendrik; Leukel, Christian; Seelig, Harald; Fuchs, Reinhard

2017-01-01

This study investigates the role of placebo expectations in individuals' perception of exertion during acute physical exercise. Building upon findings from placebo and marketing research, we examined how perceived exertion is affected by expectations regarding a) the effects of exercise and b) the effects of the exercise product worn during the exercise. We also investigated whether these effects are moderated by physical self-concept. Seventy-eight participants conducted a moderate 30 min cycling exercise on an ergometer, with perceived exertion (RPE) measured every 5 minutes. Beforehand, each participant was randomly assigned to 1 of 4 conditions and watched a corresponding film clip presenting "scientific evidence" that the exercise would or would not result in health benefits and that the exercise product they were wearing (compression garment) would additionally enhance exercise benefits or would only be worn for control purposes. Participants' physical self-concept was assessed via questionnaire. Results partially demonstrated that participants with more positive expectations experienced reduced perceived exertion during the exercise. Furthermore, our results indicate a moderator effect of physical self-concept: Individuals with a high physical self-concept benefited (in terms of reduced perceived exertion levels) in particular from an induction of generally positive expectations. In contrast, individuals with a low physical self-concept benefited when positive expectations were related to the exercise product they were wearing. In sum, these results suggest that placebo expectations may be a further, previously neglected class of psychological factors that influence the perception of exertion.

Do placebo expectations influence perceived exertion during physical exercise?

PubMed Central

Leukel, Christian; Seelig, Harald; Fuchs, Reinhard

2017-01-01

This study investigates the role of placebo expectations in individuals’ perception of exertion during acute physical exercise. Building upon findings from placebo and marketing research, we examined how perceived exertion is affected by expectations regarding a) the effects of exercise and b) the effects of the exercise product worn during the exercise. We also investigated whether these effects are moderated by physical self-concept. Seventy-eight participants conducted a moderate 30 min cycling exercise on an ergometer, with perceived exertion (RPE) measured every 5 minutes. Beforehand, each participant was randomly assigned to 1 of 4 conditions and watched a corresponding film clip presenting “scientific evidence” that the exercise would or would not result in health benefits and that the exercise product they were wearing (compression garment) would additionally enhance exercise benefits or would only be worn for control purposes. Participants’ physical self-concept was assessed via questionnaire. Results partially demonstrated that participants with more positive expectations experienced reduced perceived exertion during the exercise. Furthermore, our results indicate a moderator effect of physical self-concept: Individuals with a high physical self-concept benefited (in terms of reduced perceived exertion levels) in particular from an induction of generally positive expectations. In contrast, individuals with a low physical self-concept benefited when positive expectations were related to the exercise product they were wearing. In sum, these results suggest that placebo expectations may be a further, previously neglected class of psychological factors that influence the perception of exertion. PMID:28662168

Instructions to "put the phone down" do not improve the quality of bystander initiated dispatcher-assisted cardiopulmonary resuscitation.

PubMed

Brown, Todd B; Saini, Devashish; Pepper, Tracy; Mirza, Muzna; Nandigam, Hari Krishna; Kaza, Niroop; Cofield, Stacey S

2008-02-01

The quality of early bystander CPR appears important in maximizing survival. This trial tests whether explicit instructions to "put the phone down" improve the quality of bystander initiated dispatch-assisted CPR. In a randomized, double-blinded, controlled trial, subjects were randomized to a modified version of the Medical Priority Dispatch System (MPDS) version 11.2 protocol or a simplified protocol, each with or without instruction to "put the phone down" during CPR. Data were recorded from a Laerdal Resusci Anne Skillreporter manikin. A simulated emergency medical dispatcher, contacted by cell phone, delivered standardized instructions. Primary outcome measures included chest compression rate, depth, and the proportion of compressions without error, with correct hand position, adequate depth, and total release. Time was measured in two distinct ways: time required for initiation of CPR and total amount of time hands were off the chest during CPR. Proportions were analyzed by Wilcoxon rank sum tests and time variables with ANOVA. All tests used a two-sided alpha-level of 0.05. Two hundred and fifteen subjects were randomized-107 in the "put the phone down" instruction group and 108 in the group without "put the phone down" instructions. The groups were comparable across demographic and experiential variables. The additional instruction to "put the phone down" had no effect on the proportion of compressions administered without error, with the correct depth, and with the correct hand position. Likewise, "put the phone down" did not affect the average compression depth, the average compression rate, the total hands-off-chest time, or the time to initiate chest compressions. A statistically significant, yet trivial, effect was found in the proportion of compressions with total release of the chest wall. Instructions to "put the phone down" had no effect on the quality of bystander initiated dispatcher-assisted CPR in this trial.

Bystander Reaction to Women Fighting: Developing a Theory of Intervention

ERIC Educational Resources Information Center

Lowe, Robert D.; Levine, Mark; Best, Rachel M.; Heim, Derek

2012-01-01

This article explores accounts of bystanders to female-on-female public violence. Group interviews with participants in the night-time economy are carried out. Whereas men tend to respond to the discussion topic of female-on-female violence with laughter, this laughter reveals ambivalence and discomfort as much as amusement. Men seem to negotiate…

R.U. Ready?: Peer Education and Bystander Intervention Sexual Assault Programming

ERIC Educational Resources Information Center

Schweer, Jen Luettel; Heather, Katie; Kay, Kathryn; Stewart, K. Leigh; Kovach, Laura

2012-01-01

R.U. Ready? at Georgetown University is an annual sexual assault awareness event that incorporates peer education and resources with opportunities for students, staff, and faculty to dialogue about providing bystander intervention throughout the campus community. Beyond dialogue, participants learn about student activism and the resources and…

Basolateral amygdalar D2 receptor activation is required for the companions-exerted suppressive effect on the cocaine conditioning.

PubMed

Tzeng, Wen-Yu; Cherng, Chian-Fang G; Yu, Lung; Wang, Ching-Yi

2017-01-01

The presence of companions renders decreases in cocaine-stimulated dopamine release in the nucleus accumbens and cocaine-induced conditioned place preference (CPP) magnitude. Limbic systems are widely believed to underlie the modulation of accumbal dopamine release and cocaine conditioning. Thus, this study aimed to assess whether intact basolateral nucleus of amygdala (BLA), dorsal hippocampus (DH), and dorsolateral striatum (DLS) is required for the companions-exerted suppressive effect on the cocaine-induced CPP. Three cage mates, serving as companions, were arranged to house with the experimental mice in the cocaine conditioning compartment throughout the cocaine conditioning sessions. Approximately 1week before the conditioning procedure, intracranial ibotenic acid infusions were done in an attempt to cause excitotoxic lesions targeting bilateral BLA, DH and DLS. Albeit their BLA, DH, and DLS lesions, the lesioned mice exhibited comparable cocaine-induced CPP magnitudes compared to the intact and sham lesion controls. Bilateral BLA, but not DH or DLS, lesions abolished the companions-exerted suppressive effect on the cocaine-induced CPP. Intact mice receiving intra-BLA infusion of raclopride, a selective D2 antagonist, 30min prior to the cocaine conditioning did not exhibit the companions-exerted suppressive effect on the cocaine-induced CPP. Intra-BLA infusion of Sch23390, a selective D1 antagonist, did not affect the companions-exerted suppressive effect on the CPP. These results, taken together, prompt us to conclude that the intactness of BLA is required for the companions-exerted suppressive effect on the cocaine-induced CPP. Importantly, activation of D2 receptor in the BLA is required for such suppressive effect on the CPP. Copyright © 2016 Elsevier Inc. All rights reserved.

Deconstructing Attitudes About Intimate Partner Violence and Bystander Intervention: The Roles of Perpetrator Gender and Severity of Aggression.

PubMed

Ermer, Ashley E; Roach, Andrea L; Coleman, Marilyn; Ganong, Lawrence

2017-10-01

In this mixed methods study, we explored how gender of an aggressor and the levels of aggression (i.e., yelling, throwing a drink, slapping, and punching) influenced attitudes about (a) public displays of intimate partner violence (IPV) and (b) bystander intervention. A feminist-informed, social constructionist perspective guided the study. Participants ( N = 562) responded online to randomly assigned factorial vignettes. Participants ranged in age between 18 and 70 years. The majority were female, self-identified as heterosexual, and identified as White. Logistic regressions revealed that participants significantly viewed aggression as unacceptable, especially in cases of more severe and male-perpetrated aggressions. Multinomial logistic regressions revealed that participants significantly thought bystanders or friends of the couple should intervene, especially in cases of male-perpetrated and/or more severe aggression. Analyses of qualitative responses indicated that participants viewed aggression as never okay, as poor communication, as justified if provoked, and discussed the gendered double standard of aggression (i.e., men should not be aggressive because they could cause more harm than females and female-perpetrated aggression is minor, in comparison). Regarding attitudes about bystander intervention, analyses of qualitative responses indicated that aggression severity, issues surrounding relationship privacy, factors relevant to the situation (e.g., if the event occurred once or repeatedly), perceptions that help was needed (e.g., if the victim was hurt), and the bystander's relationship with the victim (i.e., friend or not) were important to consider when thinking about the decision to intervene in public acts of violence. These findings have implications for bystander intervention programs and for how individuals view public acts of IPV.

Gender-Equitable Attitudes, Bystander Behavior, and Recent Abuse Perpetration Against Heterosexual Dating Partners of Male High School Athletes

PubMed Central

Tancredi, Daniel J.; Silverman, Jay G.; Decker, Michele R.; Austin, S. Bryn; McCormick, Marie C.; Virata, Maria Catrina; Miller, Elizabeth

2013-01-01

Objectives. We assessed the relationship between gender attitudes, identified as a critical component of violence prevention, and abuse toward dating partners among adolescent male athletes. Methods. Our sample comprised 1699 athletes from 16 high schools in northern California who were surveyed between December 2009 and October 2010 in the larger Coaching Boys Into Men trial. We used logistic regression to assess the association between gender-equitable attitudes, bystander behavior, and recent abuse incidents. Results. Athletes with more gender-equitable attitudes and greater intention to intervene were less likely (adjusted odds ratio [AOR] = 0.36; 95% confidence interval [CI] = 0.28, 0.46; and AOR = 0.60; 95% CI = 0.48, 0.75, respectively) and athletes who engaged in negative bystander behavior were more likely (AOR = 1.22, 95% CI = 1.10, 1.35) to perpetrate abuse against their female dating partners. Conclusions. Despite the shift among bystander intervention programs toward gender neutrality, our findings suggest a strong association between gender attitudes and dating violence. Programs designed for adolescents should include discussion of gender attitudes and target bystander behavior, because these components may operate on related but distinct pathways to reduce abuse. PMID:23947324

Being a Positive Bystander: Male Antiviolence Allies' Experiences of "Stepping up"

ERIC Educational Resources Information Center

Casey, Erin A.; Ohler, Kristin

2012-01-01

As bystander approaches become increasingly prevalent elements of sexual and domestic violence prevention efforts, it is necessary to better understand the factors that support or impede individuals in taking positive action in the face of aggressive or disrespectful behavior from others. This study presents descriptive findings about the…

Aggressive Attitudes and Prevalence of Bullying Bystander Behavior in Middle School

ERIC Educational Resources Information Center

Datta, Pooja; Cornell, Dewey; Huang, Francis

2016-01-01

Separate lines of research find that proaggressive attitudes promote peer aggression and that bystanders play a pivotal role in deterring or facilitating bullying behavior. The current study hypothesized that proaggressive attitudes in middle school would deter students from standing up to bullying and encourage them to reinforce bullying…

Selective Mitochondrial Targeting Exerts Anxiolytic Effects In Vivo.

PubMed

Nussbaumer, Markus; Asara, John M; Teplytska, Larysa; Murphy, Michael P; Logan, Angela; Turck, Christoph W; Filiou, Michaela D

2016-06-01

Current treatment strategies for anxiety disorders are predominantly symptom-based. However, a third of anxiety patients remain unresponsive to anxiolytics highlighting the need for more effective, mechanism-based therapeutic approaches. We have previously compared high vs low anxiety mice and identified changes in mitochondrial pathways, including oxidative phosphorylation and oxidative stress. In this work, we show that selective pharmacological targeting of these mitochondrial pathways exerts anxiolytic effects in vivo. We treated high anxiety-related behavior (HAB) mice with MitoQ, an antioxidant that selectively targets mitochondria. MitoQ administration resulted in decreased anxiety-related behavior in HAB mice. This anxiolytic effect was specific for high anxiety as MitoQ treatment did not affect the anxiety phenotype of C57BL/6N and DBA/2J mouse strains. We furthermore investigated the molecular underpinnings of the MitoQ-driven anxiolytic effect and found that MitoQ treatment alters the brain metabolome and that the response to MitoQ treatment is characterized by distinct molecular signatures. These results indicate that a mechanism-driven approach based on selective mitochondrial targeting has the potential to attenuate the high anxiety phenotype in vivo, thus paving the way for translational implementation as long-term MitoQ administration is well-tolerated with no reported side effects in mice and humans.

The impact of ultra-brief chest compression-only CPR video training on responsiveness, compression rate, and hands-off time interval among bystanders in a shopping mall.

PubMed

Panchal, Ashish R; Meziab, Omar; Stolz, Uwe; Anderson, Wes; Bartlett, Mitchell; Spaite, Daniel W; Bobrow, Bentley J; Kern, Karl B

2014-09-01

Recent studies have demonstrated higher-quality chest compressions (CCs) following a 60 s ultra-brief video (UBV) on compression-only CPR (CO-CPR). However, the effectiveness of UBVs as a CPR-teaching tool for lay bystanders in public venues remains unknown. Determine whether an UBV is effective in teaching laypersons CO-CPR in a public setting and if viewing leads to superior responsiveness and CPR skills. Adult lay bystanders were enrolled in a public shopping mall and randomized to: (1) Control (CTR): sat idle for 60 s; (2) UBV: watched a 60 s UBV on CO-CPR. Subjects were read a scenario detailing a sudden collapse in the mall and asked to do what they "thought was best" on a mannequin. Performance measures were recorded for 2 min: responsiveness (time to call 911 and first CCs) and CPR quality [CC depth, rate, hands-off interval (time without CC after first CC)]. One hundred subjects were enrolled. Demographics were similar between groups. UBV subjects called 911 more frequently (percent difference: 31%) and initiated CCs sooner in the arrest scenario (median difference (MD): 5 s). UBV cohort had increased CC rate (MD: 19 cpm) and decreased hands-off interval (MD: 27 s). There was no difference in CC depth. Bystanders with UBV training in a shopping mall had significantly improved responsiveness, CC rate, and decreased hands-off interval. Given the short length of training, UBV may have potential as a ubiquitous intervention for public venues to help improve bystander reaction to arrest and CO-CPR performance. Published by Elsevier Ireland Ltd.

RETRACTED ARTICLE: Personal distress, but not sympathy, predicts the negative influence of bystanders on responding to an emergency.

PubMed

2015-06-01

At the request of the authors this article has been retracted. During the preparation of a follow-up study, a mistake was found in the experimental script of the cued reaction time task of experiment 2. Four out of six conditions were mislabeled. Consequently, the reported findings and their interpretation and discussion are incorrect. Careful reexamination and reanalyzing of the data using the correct labels revealed a pattern of results that is not entirely compatible with several of the main claims of the article. Importantly, the corrected results show that reaction times do not increase with more bystanders present at an emergency.Moreover, not only personal distress but also perspective taking predicts the negative influence of bystanders on reaction times.We believe that these new findings undermine our central claim of decreased action preparation as a function of bystanders present at an emergency and the enhancement of this effect in people with higher levels of trait personal distress. While the results and discussion of experiment 1 and 3 remain correct, the new results of experiment 2 influence the article to such an extent that we currently see no other option than to retract the article from publication. We will continue to work on this topic and hope to publish the new results in due time. We deeply regret the publication of invalid results.We sincerely apologize to the Editor and reviewers of the manuscript, and the readers of Cognitive, Affective, & Behavioral Neuroscience.

Perceived exertion. Antecedents and applications.

PubMed

Watt, B; Grove, R

1993-04-01

The field of perceived exertion has largely concerned itself with the problem of identifying the primary antecedents to this psychophysiological phenomenon. A vast literature has evolved addressing this problem, but it is fraught with contradictions. At this stage a comprehensive theory of perceived exertion does not exist. It is generally accepted that perception of exertion is dominated by physiological determinants. Physiological sensory cues have been separated into 2 categories: local factors (sensations from the working muscles and joints), and central factors (sensations from the cardiopulmonary system). Major reviews in this area generally agree that local factors dominate perception of exertion. Recent work in perceived exertion has placed an emphasis on examining the contributing psychological factors. Research into the psychological factors affecting perceived exertion has been highly fragmented with no apparent theoretical framework as a base. At the same time it is clear that an integration of psychological and physiological variables is required to obtain theoretically meaningful knowledge of this multidimensional construct. The assumed dominance of physiological factors has been challenged by the contention that in field situations, in which a variety of social psychological influences operate, psychological determinants of perceived exertion may be vastly more influential than previously estimated. Identification of the primary determinants of perceived exertion and knowledge of how these factors are integrated is vital for a concrete theory of perceived exertion to evolve.

Educating for Justice: Creating a Mission-Driven Model of Bystander Intervention to Address Sexual Violence at U.S. Catholic Colleges and Universities

ERIC Educational Resources Information Center

Galarneau, Joy; O'Neill, Shannon

2015-01-01

This article presents bystander intervention education as a best-practice approach to sexual violence prevention in college settings. It draws out a connection between mission-specific resources that can be used to advance the prevention agenda, while examining how bystander intervention education can deepen community engagement in collegiate…

Bystander killing effect of DS-8201a, a novel anti-human epidermal growth factor receptor 2 antibody-drug conjugate, in tumors with human epidermal growth factor receptor 2 heterogeneity.

PubMed

Ogitani, Yusuke; Hagihara, Katsunobu; Oitate, Masataka; Naito, Hiroyuki; Agatsuma, Toshinori

2016-07-01

Antibody-drug conjugates deliver anticancer agents selectively and efficiently to tumor tissue and have significant antitumor efficacy with a wide therapeutic window. DS-8201a is a human epidermal growth factor receptor 2 (HER2)-targeting antibody-drug conjugate prepared using a novel linker-payload system with a potent topoisomerase I inhibitor, exatecan derivative (DX-8951 derivative, DXd). It was effective against trastuzumab emtansine (T-DM1)-insensitive patient-derived xenograft models with both high and low HER2 expression. In this study, the bystander killing effect of DS-8201a was evaluated and compared with that of T-DM1. We confirmed that the payload of DS-8201a, DXd (1), was highly membrane-permeable whereas that of T-DM1, Lys-SMCC-DM1, had a low level of permeability. Under a coculture condition of HER2-positive KPL-4 cells and negative MDA-MB-468 cells in vitro, DS-8201a killed both cells, whereas T-DM1 and an antibody-drug conjugate with a low permeable payload, anti-HER2-DXd (2), did not. In vivo evaluation was carried out using mice inoculated with a mixture of HER2-positive NCI-N87 cells and HER2-negative MDA-MB-468-Luc cells by using an in vivo imaging system. In vivo, DS-8201a reduced the luciferase signal of the mice, indicating suppression of the MDA-MB-468-Luc population; however, T-DM1 and anti-HER2-DXd (2) did not. Furthermore, it was confirmed that DS-8201a was not effective against MDA-MB-468-Luc tumors inoculated at the opposite side of the NCI-N87 tumor, suggesting that the bystander killing effect of DS-8201a is observed only in cells neighboring HER2-positive cells, indicating low concern in terms of systemic toxicity. These results indicated that DS-8201a has a potent bystander effect due to a highly membrane-permeable payload and is beneficial in treating tumors with HER2 heterogeneity that are unresponsive to T-DM1. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer

Electronic Cigarettes and Indoor Air Quality: A Simple Approach to Modeling Potential Bystander Exposures to Nicotine

PubMed Central

Colard, Stéphane; O’Connell, Grant; Verron, Thomas; Cahours, Xavier; Pritchard, John D.

2014-01-01

There has been rapid growth in the use of electronic cigarettes (“vaping”) in Europe, North America and elsewhere. With such increased prevalence, there is currently a debate on whether the aerosol exhaled following the use of e-cigarettes has implications for the quality of air breathed by bystanders. Conducting chemical analysis of the indoor environment can be costly and resource intensive, limiting the number of studies which can be conducted. However, this can be modelled reasonably accurately based on empirical emissions data and using some basic assumptions. Here, we present a simplified model, based on physical principles, which considers aerosol propagation, dilution and extraction to determine the potential contribution of a single puff from an e-cigarette to indoor air. From this, it was then possible to simulate the cumulative effect of vaping over time. The model was applied to a virtual, but plausible, scenario considering an e-cigarette user and a non-user working in the same office space. The model was also used to reproduce published experimental studies and showed good agreement with the published values of indoor air nicotine concentration. With some additional refinements, such an approach may be a cost-effective and rapid way of assessing the potential exposure of bystanders to exhaled e-cigarette aerosol constituents. PMID:25547398

Guidelines for Bystander First Aid 2016.

PubMed

Pek, Jen Heng

2017-07-01

Cardiac life support is a form of first aid for cardiac emergencies. However, research and evidence in this field is lacking compared with other forms of first aid. Having identified the common emergencies that are encountered in the hospital, based on the available evidence, we have put together what could be an evidence-based approach to the first aid management of some of these common emergencies, viz. breathlessness, chest pain, allergies, stroke, heat injury, poisoning, unconsciousness, seizures, and trauma situations such as bleeding, wounds, contusions, head injury, burns and fractures. Educating the public is the key to developing a first responder bystander. These guidelines could become the basis for training of the public. Copyright: © Singapore Medical Association.

Alkylating chemotherapy may exert a uniquely deleterious effect upon neo-antigen-targeting anticancer vaccination

PubMed Central

Litterman, Adam J; Dudek, Arkadiusz Z; Largaespada, David A

2013-01-01

Alkylating chemotherapy exerts both antineoplastic and immunostimulatory effects. However, in addition to depleting regulatory T cells (Treg), alkylating agents also mediate a long lasting antiproliferative effect on responder lymphocytes. Our recent findings indicate that this antiproliferative effect profoundly impairs vaccination-induced immune responses, especially in the case of vaccines that target specific tumor-associated neo-antigens that do not require Treg depletion. PMID:24251080

Bystander responses to a violent incident in an immersive virtual environment.

PubMed

Slater, Mel; Rovira, Aitor; Southern, Richard; Swapp, David; Zhang, Jian J; Campbell, Claire; Levine, Mark

2013-01-01

Under what conditions will a bystander intervene to try to stop a violent attack by one person on another? It is generally believed that the greater the size of the crowd of bystanders, the less the chance that any of them will intervene. A complementary model is that social identity is critical as an explanatory variable. For example, when the bystander shares common social identity with the victim the probability of intervention is enhanced, other things being equal. However, it is generally not possible to study such hypotheses experimentally for practical and ethical reasons. Here we show that an experiment that depicts a violent incident at life-size in immersive virtual reality lends support to the social identity explanation. 40 male supporters of Arsenal Football Club in England were recruited for a two-factor between-groups experiment: the victim was either an Arsenal supporter or not (in-group/out-group), and looked towards the participant for help or not during the confrontation. The response variables were the numbers of verbal and physical interventions by the participant during the violent argument. The number of physical interventions had a significantly greater mean in the in-group condition compared to the out-group. The more that participants perceived that the Victim was looking to them for help the greater the number of interventions in the in-group but not in the out-group. These results are supported by standard statistical analysis of variance, with more detailed findings obtained by a symbolic regression procedure based on genetic programming. Verbal interventions made during their experience, and analysis of post-experiment interview data suggest that in-group members were more prone to confrontational intervention compared to the out-group who were more prone to make statements to try to diffuse the situation.

Bystander Responses to a Violent Incident in an Immersive Virtual Environment

PubMed Central

Slater, Mel; Rovira, Aitor; Southern, Richard; Swapp, David; Zhang, Jian J.; Campbell, Claire; Levine, Mark

2013-01-01

Under what conditions will a bystander intervene to try to stop a violent attack by one person on another? It is generally believed that the greater the size of the crowd of bystanders, the less the chance that any of them will intervene. A complementary model is that social identity is critical as an explanatory variable. For example, when the bystander shares common social identity with the victim the probability of intervention is enhanced, other things being equal. However, it is generally not possible to study such hypotheses experimentally for practical and ethical reasons. Here we show that an experiment that depicts a violent incident at life-size in immersive virtual reality lends support to the social identity explanation. 40 male supporters of Arsenal Football Club in England were recruited for a two-factor between-groups experiment: the victim was either an Arsenal supporter or not (in-group/out-group), and looked towards the participant for help or not during the confrontation. The response variables were the numbers of verbal and physical interventions by the participant during the violent argument. The number of physical interventions had a significantly greater mean in the in-group condition compared to the out-group. The more that participants perceived that the Victim was looking to them for help the greater the number of interventions in the in-group but not in the out-group. These results are supported by standard statistical analysis of variance, with more detailed findings obtained by a symbolic regression procedure based on genetic programming. Verbal interventions made during their experience, and analysis of post-experiment interview data suggest that in-group members were more prone to confrontational intervention compared to the out-group who were more prone to make statements to try to diffuse the situation. PMID:23300991

Selective Mitochondrial Targeting Exerts Anxiolytic Effects In Vivo

PubMed Central

Nussbaumer, Markus; Asara, John M; Teplytska, Larysa; Murphy, Michael P; Logan, Angela; Turck, Christoph W; Filiou, Michaela D

2016-01-01

Current treatment strategies for anxiety disorders are predominantly symptom-based. However, a third of anxiety patients remain unresponsive to anxiolytics highlighting the need for more effective, mechanism-based therapeutic approaches. We have previously compared high vs low anxiety mice and identified changes in mitochondrial pathways, including oxidative phosphorylation and oxidative stress. In this work, we show that selective pharmacological targeting of these mitochondrial pathways exerts anxiolytic effects in vivo. We treated high anxiety-related behavior (HAB) mice with MitoQ, an antioxidant that selectively targets mitochondria. MitoQ administration resulted in decreased anxiety-related behavior in HAB mice. This anxiolytic effect was specific for high anxiety as MitoQ treatment did not affect the anxiety phenotype of C57BL/6N and DBA/2J mouse strains. We furthermore investigated the molecular underpinnings of the MitoQ-driven anxiolytic effect and found that MitoQ treatment alters the brain metabolome and that the response to MitoQ treatment is characterized by distinct molecular signatures. These results indicate that a mechanism-driven approach based on selective mitochondrial targeting has the potential to attenuate the high anxiety phenotype in vivo, thus paving the way for translational implementation as long-term MitoQ administration is well-tolerated with no reported side effects in mice and humans. PMID:26567514

Psychological stress exerts an adjuvant effect on skin dendritic cell functions in vivo.

PubMed

Saint-Mezard, Pierre; Chavagnac, Cyril; Bosset, Sophie; Ionescu, Marius; Peyron, Eric; Kaiserlian, Dominique; Nicolas, Jean-Francois; Bérard, Frédéric

2003-10-15

Psychological stress affects the pathophysiology of infectious, inflammatory, and autoimmune diseases. However, the mechanisms by which stress could modulate immune responses in vivo are poorly understood. In this study, we report that application of a psychological stress before immunization exerts an adjuvant effect on dendritic cell (DC), resulting in increased primary and memory Ag-specific T cell immune responses. Acute stress dramatically enhanced the skin delayed-type hypersensitivity reaction to haptens, which is mediated by CD8(+) CTLs. This effect was due to increased migration of skin DCs, resulting in augmented CD8(+) T cell priming in draining lymph nodes and enhanced recruitment of CD8(+) T cell effectors in the skin upon challenge. This adjuvant effect of stress was mediated by norepinephrine (NE), but not corticosteroids, as demonstrated by normalization of the skin delayed-type hypersensitivity reaction and DC migratory properties following selective depletion of NE. These results suggest that release of NE by sympathetic nerve termini during a psychological stress exerts an adjuvant effect on DC by promoting enhanced migration to lymph nodes, resulting in increased Ag-specific T cell responses. Our findings may open new ways in the treatment of inflammatory diseases, e.g., psoriasis, allergic contact dermatitis, and atopic dermatitis.

The role of gender, values, and culture in adolescent bystanders' strategies.

PubMed

Tamm, Anni; Tulviste, Tiia

2015-02-01

We examined the relationship between adolescent bystanders' strategies for intervening in the bullying-like situation and their gender, values, and cultural origin. The sample consisted of 682 Estonian and Russian-Estonian adolescents (M age = 13.02 years). They were shown a video of a bullying-like situation with a non-intervening adult bystander and asked to describe what they would do if they, instead of the adult, witnessed that situation. Only 10% said that they would not intervene. Girls were more likely than boys to suggest multiple actions. Adolescents who valued conformity were less likely to propose using physical aggression. Doing nothing was less likely suggested by those who placed more importance on conformity and less on power. Estonian adolescents were more likely than their Russian-Estonian peers to suggest finding out what is going on, and less likely to say that they would do nothing. The findings suggest that although most adolescents express willingness to help the victim, they might not actually know how to intervene. © The Author(s) 2014.

Active defending and passive bystanding behavior in bullying: the role of personal characteristics and perceived peer pressure.

PubMed

Pozzoli, Tiziana; Gini, Gianluca

2010-08-01

This study examined the role of pro-victim attitudes, personal responsibility, coping responses to observations of bullying, and perceived peer normative pressure in explaining defending the victim and passive bystanding behavior in bullying. A total of 462 Italian early adolescents (mean age = 13.4 years, SD = 9 months) participated in the study. The behaviors were measured through two informants: each individual student and the teachers. The findings of a series of hierarchical regressions showed that, regardless of the informant, problem solving coping strategies and perceived peer normative pressure for intervention were positively associated with active help towards a bullied peer and negatively related to passivity. In contrast, distancing strategies were positively associated with passive bystanding, whereas they were negatively associated with teacher-reported defending behavior. Moreover, self-reported defending behavior was positively associated with personal responsibility for intervention, but only under conditions of low perceived peer pressure. Finally, the perception of peer pressure for intervention buffered the negative influence of distancing on passive bystanding tendencies. Future directions are discussed.

The Bystander Approach to Sexual Assault Risk Reduction: Effects on Risk Recognition, Perceived Self-Efficacy, and Protective Behavior.

PubMed

Bannon, R Sean; Foubert, John D

2017-02-01

Several characteristics of sexual assault awareness programs for women are associated with meeting the goals of risk reduction. To date, the literature lacks an exploration of how single-sex programs affect women, particularly when they take a bystander intervention focus using women's risk recognition and avoidance as outcome measures. The purpose of this study was to investigate the effectiveness of The Women's Program (Foubert, 2011), a sexual assault awareness program geared toward women. Participants consisted of 103 undergraduate women attending a large, public university in the Midwest United States. Women in the treatment group viewed a presentation of The Women's Program, whereas the control group received no intervention. Consistent with hypotheses, program participants reported a greater ability to recognize risk cues, a greater willingness to engage in self-protective behaviors, and a greater level of perceived self-efficacy in handling threatening dating situations compared to the control group.

Helminthiasis, bystander diseases and vaccines: analysis of interaction.

PubMed

Markus, Miles B; Fincham, John E

2007-11-01

Helminthiasis has assumed a new medical and veterinary significance following the recognition of its immunomodulatory consequences for the severity of bystander conditions and the efficacy of immunization against non-helminthic diseases of humans and livestock. Recent papers by Jackson et al. and Turner et al. have an important bearing on research in these areas. One of the implications of their work is that the parasitological criterion of egg-positivity versus egg-negativity is too simplistic to use in co-infection and related studies unless accompanied by immunological analysis.

The impact of bystanding to workplace bullying on symptoms of depression among women and men in industry in Sweden: an empirical and theoretical longitudinal study.

PubMed

Emdad, R; Alipour, A; Hagberg, J; Jensen, I B

2013-08-01

Prospective studies on bystanding to workplace bullying and the health outcomes are scarce. To investigate the work environmental risk factors of depressive symptoms among bystanders to bullying in both women and men in four large industrial organizations in Sweden. The number of respondents at four large industrial enterprises with more than one year at the workplace at T1: n = 2,563 (Women: n = 342; Men: n = 2,227). Bystanders to bullying at T1: n = 305 (Women: n = 30; Men: n = 275). The total number of those with symptoms of depression at T2: Women: n = 30; Men: n = 161. Two thousand one hundred and seventy-seven employees answered the questionnaire on T1 and T2 with an 18-month interval. "To have depressive symptoms" was defined as not having depressive symptoms at T1 but having depressive symptoms at T2. The number of men who were bystanders to bullying was larger compared to women. However, the proportion of women who were bystanders to bullying and developed depressive symptoms 18 months later was higher in comparison with men (33.3 and 16.4 %, respectively). Further, "Being a bystander to bullying" 1.69 (1.13-2.53), "Rumors of changes in the workplace" 1.53 (1.10-2.14), "Reduced role clarity" 2.30 (1.21-4.32), "Lack of appreciation of being in the group" 1.76 (1.22-2.53) increased the risk of future symptoms of depression. "Job Strain" was not an adjusted risk factor for depression. Our results support previous findings that bystanding to workplace bullying is related to future depressive symptoms.

Perspectives on Exertional Rhabdomyolysis.

PubMed

Rawson, Eric S; Clarkson, Priscilla M; Tarnopolsky, Mark A

2017-03-01

Exertional (exercise-induced) rhabdomyolysis is a potentially life threatening condition that has been the subject of research, intense discussion, and media attention. The causes of rhabdomyolysis are numerous and can include direct muscle injury, unaccustomed exercise, ischemia, extreme temperatures, electrolyte abnormalities, endocrinologic conditions, genetic disorders, autoimmune disorders, infections, drugs, toxins, and venoms. The objective of this article is to review the literature on exertional rhabdomyolysis, identify precipitating factors, and examine the role of the dietary supplement creatine monohydrate. PubMed and SPORTDiscus databases were searched using the terms rhabdomyolysis, muscle damage, creatine, creatine supplementation, creatine monohydrate, and phosphocreatine. Additionally, the references of papers identified through this search were examined for relevant studies. A meta-analysis was not performed. Although the prevalence of rhabdomyolysis is low, instances still occur where exercise is improperly prescribed or used as punishment, or incomplete medical history is taken, and exertional rhabdomyolysis occurs. Creatine monohydrate does not appear to be a precipitating factor for exertional rhabdomyolysis. Healthcare professionals should be able to recognize the basic signs of exertional rhabdomyolysis so prompt treatment can be administered. For the risk of rhabdomyolysis to remain low, exercise testing and prescription must be properly conducted based on professional standards.

Enteropathogenic Escherichia coli: foe or innocent bystander?

PubMed Central

Hu, Jia; Torres, Alfredo G.

2015-01-01

Enteropathogenic Escherichia coli (EPEC) remain one the most important pathogens infecting children and they are one of the main causes of persistent diarrhea worldwide. Historically, typical EPEC (tEPEC), defined as those isolates with the attaching and effacement (A/E) genotype (eae+), which possess bfpA+ and lack the stx- genes are found strongly associated with diarrheal cases. However, occurrence of atypical EPEC (aEPEC; eae+ bfpA- stx-) in diarrheal and asymptomatic hosts has made investigators question the role of these pathogens in human disease. Current epidemiological data is helping answering the question whether EPEC is mainly a foe or an innocent bystander during infection. PMID:25726041

Video calls from lay bystanders to dispatch centers - risk assessment of information security.

PubMed

Bolle, Stein R; Hasvold, Per; Henriksen, Eva

2011-09-30

Video calls from mobile phones can improve communication during medical emergencies. Lay bystanders can be instructed and supervised by health professionals at Emergency Medical Communication Centers. Before implementation of video mobile calls in emergencies, issues of information security should be addressed. Information security was assessed for risk, based on the information security standard ISO/IEC 27005:2008. A multi-professional team used structured brainstorming to find threats to the information security aspects confidentiality, quality, integrity, and availability. Twenty security threats of different risk levels were identified and analyzed. Solutions were proposed to reduce the risk level. Given proper implementation, we found no risks to information security that would advocate against the use of video calls between lay bystanders and Emergency Medical Communication Centers. The identified threats should be used as input to formal requirements when planning and implementing video calls from mobile phones for these call centers.

Translating sexual assault prevention from a college campus to a United States military installation: piloting the know-your-power bystander social marketing campaign.

PubMed

Potter, Sharyn J; Stapleton, Jane G

2012-05-01

One population that shares both similar and different characteristics with traditional college-age students is the U.S. Military. Similarities include a high concentration of 18- to 26-year-olds dealing with new found independence, peer pressure, and the presence of social norms that support violence and hypermasculinity. Sexual violence is a major public health problem in the United States, and because of the similarities in the age group of college and military populations, the problems regarding sexual violence in both constituencies have been well-documented. In the current pilot study we seek to add to both current knowledge about and promising practices of translating prevention strategies from one target audience to another. We describe how we translated, administered, and evaluated a bystander intervention social marketing campaign focused on sexual assault prevention that had been found to significantly affect attitude change on a college campus for a U.S. Army installation in Europe. In addition to demonstrating the process of translating prevention strategies across target audiences, findings from this pilot study contribute to the evaluation data on the effectiveness of sexual violence prevention strategies implemented with members of the U.S. Military. From our analysis, we see that research participants indicate that the degree to which the images resonate with them and the familiarity of the context (i.e., social self-identification) significantly effect the participants' personal responsibility for reducing sexual assault, confidence in acting as a bystander, and reported engagement as a bystander.

The effects of therapeutic instrumental music performance on endurance level, self-perceived fatigue level, and self-perceived exertion of inpatients in physical rehabilitation.

PubMed

Lim, Hayoung A; Miller, Karen; Fabian, Chuck

2011-01-01

The present study investigated the effects of a Neurologic Music Therapy (NMT) sensory-motor rehabilitation technique, Therapeutic Instrumental Music Performance (TIMP) as compared to Traditional Occupational Therapy (TOT), on endurance, self-perceived fatigue, and self-perceived exertion of 35 hospitalized patients in physical rehabilitation. The present study attempted to examine whether an active musical experience such as TIMP with musical cueing (i.e., rhythmic auditory cueing) during physical exercises influences one's perception of pain, fatigue, and exertion. All participants were diagnosed with a neurologic disorder or had recently undergone orthopedic surgery. Investigators measured the effects of TOT and TIMP during upper extremity exercise of the less affected or stronger upper extremity. Results showed no significant difference on endurance measures between the 2 treatment conditions (TIMP and TOT). Statistically significant differences were found between TIMP and TOT when measuring their effects on perceived exertion and perceived fatigue. TIMP resulted in significantly less perception of fatigue and exertion levels than TOT. TIMP can be used foran effective sensory-motor rehabilitation technique to decrease perceived exertion and fatigue level of inpatients in physical rehabilitation.

Participant Roles in Bullying: How Can Peer Bystanders Be Utilized in Interventions?

ERIC Educational Resources Information Center

Salmivalli, Christina

2014-01-01

This article provides a view of school bullying as a group phenomenon and practical implications stemming from this approach. The motivation for bullying perpetration often relates to one's social standing in the group. Peer bystanders are typically present when bullying takes place, often providing the perpetrators with social rewards. The…

Bystanders to Bullying: Fourth-to Seventh-Grade Students' Perspectives on Their Reactions

ERIC Educational Resources Information Center

Forsberg, Camilla; Thornberg, Robert; Samuelsson, Marcus

2014-01-01

The aim with the present study was to investigate bystander actions in bullying situations as well as reasons behind these actions as they are articulated by Swedish students from fourth to seventh grade. Forty-three semi-structured individual interviews were conducted with students. Qualitative analysis of data was performed by methods from…

Losartan exerts no protective effects against acute pulmonary embolism-induced hemodynamic changes.

PubMed

Dias, Carlos A; Neto-Neves, Evandro M; Montenegro, Marcelo F; Tanus-Santos, Jose E

2012-02-01

The acute obstruction of pulmonary vessels by venous thrombi is a critical condition named acute pulmonary embolism (APE). During massive APE, severe pulmonary hypertension may lead to death secondary to right heart failure and circulatory shock. APE-induced pulmonary hypertension is aggravated by active pulmonary vasoconstriction. While blocking the effects of some vasoconstrictors exerts beneficial effects, no previous study has examined whether angiotensin II receptor blockers protect against the hemodynamic changes associated with APE. We examined the effects exerted by losartan on APE-induced hemodynamic changes. Hemodynamic evaluations were performed in non-embolized lambs treated with saline (n = 4) and in lambs that were embolized with silicon microspheres and treated with losartan (30 mg/kg followed by 1 mg/kg/h, n = 5) or saline (n = 7) infusions. The plasma and lung angiotensin-converting enzyme (ACE) activity were assessed using a fluorometric method. APE increased mean pulmonary arterial pressure (MPAP) and pulmonary vascular resistance index (PVRI) by 21 ± 2 mmHg and 375 ± 20 dyn s cm⁻⁵ m⁻², respectively (P < 0.05). Losartan decreased MPAP significantly (by approximately 15%), without significant changes in PVRI and tended to decrease cardiac index (P > 0.05). Lung and plasma ACE activity were similar in both embolized and non-embolized animals. Our findings show evidence of lack of activation of the renin-angiotensin system during APE. The lack of significant effects of losartan on the pulmonary vascular resistance suggests that losartan does not protect against the hemodynamic changes found during APE.

Exertion Testing in Youth with Mild Traumatic Brain Injury/Concussion.

PubMed

Dematteo, Carol; Volterman, Kimberly A; Breithaupt, Peter G; Claridge, Everett A; Adamich, John; Timmons, Brian W

2015-11-01

The decision regarding return to activity (RTA) after mild traumatic brain injuries/concussion is one of the most difficult and controversial areas in concussion management, particularly for youth. This study investigated how youth with postconcussion syndrome (PCS) are affected by exertion and whether standardized exertion testing using the McMaster All-Out Progressive Continuous Cycling Test can contribute to clinical decision making for safe RTA. Fifty-four youth (8.5-18.3 yr) with a previously confirmed concussion participated in the study. Each participant performed exertion testing on a cycle ergometer and completed a Postconcussion Symptom scale at the following time points: before exertion (baseline), 5 and 30 min, and 24 h after exertion. A modified Postconcussion Symptom scale was administered at 2-min intervals during exertion. Participants had a mean ± SD symptom duration of 6.3 ± 6.9 months after the most recent concussive injury, with a median of 4.1 months (range, 0.7-35 months). Sixty-three percent of participants had symptoms during exertion testing. Symptom profile (number and severity) significantly affected perception of exertion at 50% peak mechanical power. During acute assessment of symptoms (30-min after exertion), headache (P = 0.39), nausea (P = 0.63), and dizziness (P = 0.35) did not change. However, both the number and severity of symptoms significantly improved over 24 h, with 56.8% of youth showing improvements. The time from the most recent injury had a significant effect on the symptom score at baseline, 30 min after exertion, and 24 h after exertion. Exertion testing has an important role in the evaluation of symptoms and readiness to RTA, particularly in youth who are slow to recover. Overall, controlled exertion seemed to lesson symptoms for most youth.

BYSTANDERS, ADAPTIVE RESPONSES AND GENOMIC INSTABILITY - POTENTIAL MODIFIERS OF LOW-DOSE CANCER RESPONSES.

EPA Science Inventory

Bystanders, Adaptive Responses and Genomic Instability -Potential Modifiers ofLow-Dose
Cancer Responses
.
There has been a concerted effort in the field of radiation biology to better understand cellular
responses that could have an impact on the estin1ation of cancer...

Video calls from lay bystanders to dispatch centers - risk assessment of information security

PubMed Central

2011-01-01

Background Video calls from mobile phones can improve communication during medical emergencies. Lay bystanders can be instructed and supervised by health professionals at Emergency Medical Communication Centers. Before implementation of video mobile calls in emergencies, issues of information security should be addressed. Methods Information security was assessed for risk, based on the information security standard ISO/IEC 27005:2008. A multi-professional team used structured brainstorming to find threats to the information security aspects confidentiality, quality, integrity, and availability. Results Twenty security threats of different risk levels were identified and analyzed. Solutions were proposed to reduce the risk level. Conclusions Given proper implementation, we found no risks to information security that would advocate against the use of video calls between lay bystanders and Emergency Medical Communication Centers. The identified threats should be used as input to formal requirements when planning and implementing video calls from mobile phones for these call centers. PMID:21958387

Effects of the Visual Exercise Environments on Cognitive Directed Attention, Energy Expenditure and Perceived Exertion

PubMed Central

Rogerson, Mike; Barton, Jo

2015-01-01

Green exercise research often reports psychological health outcomes without rigorously controlling exercise. This study examines effects of visual exercise environments on directed attention, perceived exertion and time to exhaustion, whilst measuring and controlling the exercise component. Participants completed three experimental conditions in a randomized counterbalanced order. Conditions varied by video content viewed (nature; built; control) during two consistently-ordered exercise bouts (Exercise 1: 60% VO2peakInt for 15-mins; Exercise 2: 85% VO2peakInt to voluntary exhaustion). In each condition, participants completed modified Backwards Digit Span tests (a measure of directed attention) pre- and post-Exercise 1. Energy expenditure, respiratory exchange ratio and perceived exertion were measured during both exercise bouts. Time to exhaustion in Exercise 2 was also recorded. There was a significant time by condition interaction for Backwards Digit Span scores (F2,22 = 6.267, p = 0.007). Scores significantly improved in the nature condition (p < 0.001) but did not in the built or control conditions. There were no significant differences between conditions for either perceived exertion or physiological measures during either Exercise 1 or Exercise 2, or for time to exhaustion in Exercise 2. This was the first study to demonstrate effects of controlled exercise conducted in different visual environments on post-exercise directed attention. Via psychological mechanisms alone, visual nature facilitates attention restoration during moderate-intensity exercise. PMID:26133125

Effects of the Visual Exercise Environments on Cognitive Directed Attention, Energy Expenditure and Perceived Exertion.

PubMed

Rogerson, Mike; Barton, Jo

2015-06-30

Green exercise research often reports psychological health outcomes without rigorously controlling exercise. This study examines effects of visual exercise environments on directed attention, perceived exertion and time to exhaustion, whilst measuring and controlling the exercise component. Participants completed three experimental conditions in a randomized counterbalanced order. Conditions varied by video content viewed (nature; built; control) during two consistently-ordered exercise bouts (Exercise 1: 60% VO2peakInt for 15-mins; Exercise 2: 85% VO2peakInt to voluntary exhaustion). In each condition, participants completed modified Backwards Digit Span tests (a measure of directed attention) pre- and post-Exercise 1. Energy expenditure, respiratory exchange ratio and perceived exertion were measured during both exercise bouts. Time to exhaustion in Exercise 2 was also recorded. There was a significant time by condition interaction for Backwards Digit Span scores (F2,22 = 6.267, p = 0.007). Scores significantly improved in the nature condition (p < 0.001) but did not in the built or control conditions. There were no significant differences between conditions for either perceived exertion or physiological measures during either Exercise 1 or Exercise 2, or for time to exhaustion in Exercise 2. This was the first study to demonstrate effects of controlled exercise conducted in different visual environments on post-exercise directed attention. Via psychological mechanisms alone, visual nature facilitates attention restoration during moderate-intensity exercise.

ASP6537, a novel highly selective cyclooxygenase-1 inhibitor, exerts potent antithrombotic effect without "aspirin dilemma".

PubMed

Sakata, Chinatsu; Kawasaki, Tomihisa; Kato, Yasuko; Abe, Masaki; Suzuki, Ken-ichi; Ohmiya, Makoto; Funatsu, Toshiyuki; Morita, Yoshiaki; Okada, Masamichi

2013-07-01

Aspirin inhibits both the cyclooxygenase (COX)-1-dependent production of thromboxane A2 (TXA2) in platelets and COX-2-dependent production of anti-aggregatory prostaglandin I2 (PGI2) in vessel walls, resulting in "aspirin dilemma." Our objective is to investigate whether ASP6537 can overcome aspirin dilemma and exert a potent antithrombotic effect without a concurrent ulcerogenic effect. We evaluated the inhibitory effects of ASP6537 on recombinant human COX-1 (rhCOX-1) and rhCOX-2 activities using a COX-1/2 selectivity test. To determine whether ASP6537 induces aspirin dilemma, we examined the effects of ASP6537 on in vitro TXA2 and PGI2 metabolite production from platelets and isolated aorta of guinea pigs, and on plasma concentrations of TXA2 and PGI2 metabolites in aged rats. Finally, we evaluated the antithrombotic effects and ulcerogenic activity of ASP6537 using an electrically induced carotid arterial thrombosis model and a gastric ulcer model in guinea pigs. The IC50 ratios of rhCOX-2 to rhCOX-1 for ASP6537 and aspirin were >142,000 and 1.63 fold, respectively. ASP6537 inhibited TXA2 production more selectively than aspirin in in vitro and in vivo TXA2/PGI2 production studies. ASP6537 exerted a significant antithrombotic effect at ≥3 mg/kg, while aspirin tended to inhibit thrombosis at 300 mg/kg but it was not statistically significant. Further, ASP6537 did not induce ulcer formation at 100 mg/kg, whereas aspirin exhibited an ulcerogenic effect at doses of ≥100 mg/kg. ASP6537 functions as a highly selective COX-1 inhibitor with a superior ability to aspirin for normalizing TXA2/PGI2 balance, and exerts antithrombotic effect without ulcerogenic effect. Copyright © 2013 Elsevier Ltd. All rights reserved.

Bystander cardiopulmonary resuscitation training experience and self-efficacy of age and gender group: a nationwide community survey.

PubMed

Ro, Young Sun; Shin, Sang Do; Song, Kyoung Jun; Hong, Sung Ok; Kim, Young Taek; Cho, Sung-Il

2016-08-01

We hypothesized that recent hands-on practice for cardiopulmonary resuscitation (CPR) would be strongly associated with a higher likelihood of self-efficacy in bystander CPR among laypersons according to age and gender group. We used the National Korean Community Health Survey database of 228921 representatively sampled responders from 253 counties in 2012. Laypersons who had previous CPR training were eligible. Exposure variables were having had CPR training with hands-on practice session with a manikin (Practical-CPR-Training) and CPR training within the last 2 years (Recent-CPR-Training). Primary outcome was self-efficacy in bystander CPR. Multivariable logistic regression analysis was performed. The final model with an interaction term was evaluated to compare the effects of CPR training across different age and gender groups. Of 62425 eligible respondents who have had CPR training, 20213 (32.4%) had Practical-CPR-Training. Adjusted odds ratios (AORs) for self-efficacy were 4.08 (3.78-4.41) in Practical-CPR-Training, 2.61 (2.50-2.73) in male, 1.26 (1.16-1.36) in good self-rated health, 1.19 (1.10-1.29) in high school graduate, 1.19 (1.01-1.39) in persons living with stroke patients in household, and 1.17 (1.10-1.24) in Recent-CPR-Training. In interaction models, Practical-CPR-Training showed higher self-efficacy in all age and gender groups, whereas Recent-CPR-Training was not associated with better self-efficacy in elderly group, male (AOR, 0.90 [0.69-1.18]) and female (AOR, 0.94 [0.72-1.23]). Self-efficacy in bystander CPR was higher in person with recent CPR training with hands-on practice with a manikin. Copyright © 2015 Elsevier Inc. All rights reserved.

Cannabidiol exerts sebostatic and antiinflammatory effects on human sebocytes

PubMed Central

Oláh, Attila; Tóth, Balázs I.; Borbíró, István; Sugawara, Koji; Szöllõsi, Attila G.; Czifra, Gabriella; Pál, Balázs; Ambrus, Lídia; Kloepper, Jennifer; Camera, Emanuela; Ludovici, Matteo; Picardo, Mauro; Voets, Thomas; Zouboulis, Christos C.; Paus, Ralf; Bíró, Tamás

2014-01-01

The endocannabinoid system (ECS) regulates multiple physiological processes, including cutaneous cell growth and differentiation. Here, we explored the effects of the major nonpsychotropic phytocannabinoid of Cannabis sativa, (-)-cannabidiol (CBD), on human sebaceous gland function and determined that CBD behaves as a highly effective sebostatic agent. Administration of CBD to cultured human sebocytes and human skin organ culture inhibited the lipogenic actions of various compounds, including arachidonic acid and a combination of linoleic acid and testosterone, and suppressed sebocyte proliferation via the activation of transient receptor potential vanilloid-4 (TRPV4) ion channels. Activation of TRPV4 interfered with the prolipogenic ERK1/2 MAPK pathway and resulted in the downregulation of nuclear receptor interacting protein-1 (NRIP1), which influences glucose and lipid metabolism, thereby inhibiting sebocyte lipogenesis. CBD also exerted complex antiinflammatory actions that were coupled to A2a adenosine receptor-dependent upregulation of tribbles homolog 3 (TRIB3) and inhibition of the NF-κB signaling. Collectively, our findings suggest that, due to the combined lipostatic, antiproliferative, and antiinflammatory effects, CBD has potential as a promising therapeutic agent for the treatment of acne vulgaris. PMID:25061872

The Role of Self-Efficacy for Bystander Helping Behaviors in Risky Alcohol Situations

ERIC Educational Resources Information Center

Krieger, Heather; Serrano, Surizaday; Neighbors, Clayton

2017-01-01

We examined the role of self-efficacy in preventing bystander inaction in dangerous alcohol situations. Participants (N = 504) completed an online survey that assessed whether they had previously witnessed or intervened in alcohol-related emergencies, their self-efficacy for intervening, and their likelihood of intervening in the future.…

Reducing Sexual Violence on Campus: The Role of Student Leaders as Empowered Bystanders

ERIC Educational Resources Information Center

Banyard, Victoria L.; Moynihan, Mary M.; Crossman, Maria T.

2009-01-01

Sexual violence is a widespread problem for college communities. Students, faculty, and staff are increasingly involved in prevention efforts. To date, however, evaluation of sexual violence prevention programs has shown mixed results. One promising new practice teaches segments of college communities to be engaged, positive bystanders. It aims to…

Bystander Intervention, Bullying, and Victimization: A Multilevel Analysis of New Zealand High Schools

ERIC Educational Resources Information Center

Denny, Simon; Peterson, Elizabeth R.; Stuart, Jaimee; Utter, Jennifer; Bullen, Pat; Fleming, Theresa; Ameratunga, Shanthi; Clark, Terryann; Milfont, Taciano

2015-01-01

This study examines the association between schools and student bullying behaviors and victimization among a nationally representative sample (N = 9,107) of New Zealand high school students. In particular, the study sought to explore the role of characteristics of schools and school culture with respect to bystander behavior, while controlling for…

A Web-Based Sexual Violence Bystander Intervention for Male College Students: Randomized Controlled Trial

PubMed Central

Vivolo-Kantor, Alana; Hardin, James; Berkowitz, Alan

2014-01-01

Background Bystander intervention approaches offer promise for reducing rates of sexual violence on college campuses. Most interventions are in-person small-group formats, which limit their reach and reduce their overall public health impact. Objective This study evaluated the efficacy of RealConsent, a Web-based bystander approach to sexual violence prevention, in enhancing prosocial intervening behaviors and preventing sexual violence perpetration. Methods A random probability sample of 743 male undergraduate students (aged 18 to 24 years) attending a large, urban university located in the southeastern United States was recruited online and randomized to either RealConsent (n=376) or a Web-based general health promotion program (n=367). Participants were surveyed online at baseline, postintervention, and 6-months postintervention. RealConsent was delivered via a password-protected Web portal that contained six 30-minute media-based and interactive modules covering knowledge of informed consent, communication skills regarding sex, the role of alcohol and male socialization in sexual violence, empathy for rape victims, and bystander education. Primary outcomes were self-reported prosocial intervening behaviors and sexual violence perpetration. Secondary outcomes were theoretical mediators (eg, knowledge, attitudes). Results At 6-month follow-up RealConsent participants intervened more often (P=.04) and engaged in less sexual violence perpetration (P=.04) compared to controls. In addition, RealConsent participants reported greater legal knowledge of sexual assault (P<.001), greater knowledge of effective consent (P<.001), less rape myths (P<.001), greater empathy for rape victims (P<.001), less negative date rape attitudes (P<.001), less hostility toward women (P=.01), greater intentions to intervene (P=.04), less hyper-gender ideology (P<.001), less positive outcome expectancies for nonconsensual sex (P=.03), more positive outcome expectancies for intervening (P

The importance of serum serotonin levels in the measurement of radiation-induced bystander cell death in HaCaT cells.

PubMed

Lyng, Fiona M; Desplanques, Maxime; Jella, Kishore Kumar; Garcia, Amaya; McClean, Brendan

2012-10-01

The aim of this study was to investigate the importance of serum serotonin levels in the measurement of bystander cell death. The study was undertaken as part of an intercomparison exercise involving seven European laboratories funded under the European Union Sixth Framework Programme (FP6) Non-Targeted Effects (NOTE) integrated project. Three batches of foetal bovine serum were tested; serum with high and low serotonin content from the intercomparison exercise as well as serum from the home laboratory. Three sets of human keratinocytes (HaCaT cell line) were cultured in DMEM:F12 medium supplemented with serum with high or low serotonin content or serum from the home laboratory and both donor and recipient HaCaT cells were plated. The donor HaCaT cells were irradiated (0.5 Gy) using a cobalt 60 teletherapy unit, the medium was harvested 1 hour post irradiation and transferred to the recipient HaCaT cells. Bystander induced cell death was measured by the clonogenic survival assay and the Alamar blue viability assay. A significant reduction in cell survival, as measured by the clonogenic assay, and in cell viability, as measured by the Alamar blue assay, was observed in the recipient HaCaT cells treated with medium from irradiated cells compared to the cells treated with medium from unirradiated cells. No significant difference was found between the three batches of serum. The data suggest that in our cell system and with our endpoints (clonogenic assay and Alamar blue assay), serum serotonin levels do not play a role in bystander-induced cell death.

The Effect of Cognitive Behavioral Therapy and Cognitive Behavioral Therapy Plus Media on the Reduction of Bullying and Victimization and the Increase of Empathy and Bystander Response in a Bully Prevention Program for Urban Sixth-Grade Students

ERIC Educational Resources Information Center

McLaughlin, Laura Pierce

2009-01-01

The purpose of this study was to investigate the effect of cognitive behavioral therapy and cognitive behavioral therapy plus media on the reduction of bullying and victimization and the increase in empathy and bystander response in a bully prevention program for urban sixth-graders. Sixty-eight students participated. Because one of the…

Witnessed arrest, but not delayed bystander cardiopulmonary resuscitation improves prehospital cardiac arrest survival.

PubMed

Vukmir, R B

2004-05-01

This study correlated the effect of witnessing a cardiac arrest and instituting bystander CPR (ByCPR), as a secondary end point in a study evaluating the effect of bicarbonate on survival. This prospective, randomised, double blinded clinical intervention trial enrolled 874 prehospital cardiopulmonary arrest patients encountered in a prehospital urban, suburban, and rural regional emergency medical service (EMS) area. This group underwent conventional advanced cardiac life support intervention followed by empiric early administration of sodium bicarbonate (1 mEq/l), monitoring conventional resuscitation parameters. Survival was measured as presence of vital signs on emergency department (ED) arrival. Data were analysed using chi(2) with Pearson correlation and odds ratio where appropriate. The overall survival rate was 13.9% (110 of 792) of prehospital cardiac arrest patients. The mean (SD) time until provision of bystander cardiopulmonary resuscitation (ByCPR) by laymen was 2.08 (2.77) minutes, and basic life support (BLS) by emergency medical technicians was 6.62 (5.73) minutes. There was improved survival noted with witnessed cardiac arrest-a 2.2-fold increase in survival, 18.9% (76 of 402) versus 8.6% (27 of 315) compared with unwitnessed arrests (p<0.001) with a decreased risk ratio of mortality of 0.4534 (95% CI, 0.0857 to 0.1891). The presence of ByCPR occurred in 32% (228 of 716) of patients, but interestingly did not correlate with survival. The survival rate was 18.2% (33 of 181) if ByCPR was performed within two minutes and 12.8% (6 of 47), if performed >two minutes (p = 0.3752). Survival after prehospital cardiac arrest is more likely when witnessed, but not necessarily when ByCPR was performed by laymen.

Counseling and the Bystander-Equity Model of Supervisory Helping Behavior: Directions for EAP Research.

ERIC Educational Resources Information Center

Gerstein, Lawrence H.; Bayer, Gregory A.

1991-01-01

Discusses contribution of Bystander-Equity Model of Supervisory Helping Behavior to pursuit of employee assistance program (EAP) research based on traditions of field of counseling. Offers structure for pursuing empirical and applied activities in EAP settings. Encourages counseling researchers and practitioners to respond to challenge of working…

Quality of audio-assisted versus video-assisted dispatcher-instructed bystander cardiopulmonary resuscitation: A systematic review and meta-analysis.

PubMed

Lin, Yu-You; Chiang, Wen-Chu; Hsieh, Ming-Ju; Sun, Jen-Tang; Chang, Yi-Chung; Ma, Matthew Huei-Ming

2018-02-01

This study aimed to conduct a systematic review and meta-analysis comparing the effect of video-assistance and audio-assistance on quality of dispatcher-instructed cardiopulmonary resuscitation (DI-CPR) for bystanders. Five databases were searched, including PubMed, Cochrane library, Embase, Scopus and NIH clinical trial, to find randomized control trials published before June 2017. Qualitative analysis and meta-analysis were undertaken to examine the difference between the quality of video-instructed and audio-instructed dispatcher-instructed bystander CPR. The database search yielded 929 records, resulting in the inclusion of 9 relevant articles in this study. Of these, 6 were included in the meta-analysis. Initiation of chest compressions was slower in the video-instructed group than in the audio-instructed group (median delay 31.5 s; 95% CI: 10.94-52.09). The difference in the number of chest compressions per minute between the groups was 19.9 (95% CI: 10.50-29.38) with significantly faster compressions in the video-instructed group than in the audio-instructed group (104.8 vs. 80.6). The odds ratio (OR) for correct hand positioning was 0.8 (95% CI: 0.53-1.30) when comparing the audio-instructed and video-instructed groups. The differences in chest compression depth (mm) and time to first ventilation (seconds) between the video-instructed group and audio-instructed group were 1.6 mm (95% CI: -8.75, 5.55) and 7.5 s (95% CI: -56.84, 71.80), respectively. Video-instructed DI-CPR significantly improved the chest compression rate compared to the audio-instructed method, and a trend for correctness of hand position was also observed. However, this method caused a delay in the commencement of bystander-initiated CPR in the simulation setting. Copyright © 2017 Elsevier B.V. All rights reserved.

School Personnel's Bystander Action in Situations of Dating Violence, Sexual Violence, and Sexual Harassment Among High School Teens: A Qualitative Analysis.

PubMed

Edwards, Katie M; Rodenhizer, Kara Anne; Eckstein, Robert P

2017-04-01

We examined school personnel's engagement in bystander action in situations of teen dating violence (DV), sexual violence (SV), and sexual harassment (SH). We conducted focus groups with 22 school personnel from three high schools in New Hampshire. School personnel identified their own barriers to intervening in situations of teen DV, SV, and SH (e.g., not having the time or ability to intervene). School personnel also discussed the ways in which they intervened before (e.g., talking with teens about healthy relationships), during (e.g., breaking up fights between dating partners) and after (e.g., comforting victims) instances of teen DV, SV, and SH. These data can be used to support the development of bystander training for school personnel as one component of comprehensive DV, SV, and SH prevention for teens. In addition, these data provide information that can be used to develop measures that assess school personnel bystander action barriers and behaviors in instances of teen DV, SV, and SH.

Improvements in Modelling Bystander and Resident Exposure to Pesticide Spray Drift: Investigations into New Approaches for Characterizing the 'Collection Efficiency' of the Human Body.

PubMed

Butler Ellis, M Clare; Kennedy, Marc C; Kuster, Christian J; Alanis, Rafael; Tuck, Clive R

2018-05-28

The BREAM (Bystander and Resident Exposure Assessment Model) (Kennedy et al. in BREAM: A probabilistic bystander and resident exposure assessment model of spray drift from an agricultural boom sprayer. Comput Electron Agric 2012;88:63-71) for bystander and resident exposure to spray drift from boom sprayers has recently been incorporated into the European Food Safety Authority (EFSA) guidance for determining non-dietary exposures of humans to plant protection products. The component of BREAM, which relates airborne spray concentrations to bystander and resident dermal exposure, has been reviewed to identify whether it is possible to improve this and its description of variability captured in the model. Two approaches have been explored: a more rigorous statistical analysis of the empirical data and a semi-mechanistic model based on established studies combined with new data obtained in a wind tunnel. A statistical comparison between field data and model outputs was used to determine which approach gave the better prediction of exposures. The semi-mechanistic approach gave the better prediction of experimental data and resulted in a reduction in the proposed regulatory values for the 75th and 95th percentiles of the exposure distribution.

Exertional heat illness: emerging concepts and advances in prehospital care.

PubMed

Pryor, Riana R; Roth, Ronald N; Suyama, Joe; Hostler, David

2015-06-01

Exertional heat illness is a classification of disease with clinical presentations that are not always diagnosed easily. Exertional heat stroke is a significant cause of death in competitive sports, and the increasing popularity of marathons races and ultra-endurance competitions will make treating many heat illnesses more common for Emergency Medical Services (EMS) providers. Although evidence is available primarily from case series and healthy volunteer studies, the consensus for treating exertional heat illness, coupled with altered mental status, is whole body rapid cooling. Cold or ice water immersion remains the most effective treatment to achieve this goal. External thermometry is unreliable in the context of heat stress and direct internal temperature measurement by rectal or esophageal probes must be used when diagnosing heat illness and during cooling. With rapid recognition and implementation of effective cooling, most patients suffering from exertional heat stroke will recover quickly and can be discharged home with instructions to rest and to avoid heat stress and exercise for a minimum of 48 hours; although, further research pertaining to return to activity is warranted.

Comparison of Bystander Cardiopulmonary Resuscitation (BCPR) Performance in the Absence and Presence of Timing Devices for Coordinating Delivery of Ventilatory Breaths and Cardiac Compressions in a Model of Adult Cardiopulmonary Arrest

NASA Technical Reports Server (NTRS)

Hurst, Victor, IV; West, Sarah; Austin, Paul; Branson, Richard; Beck, George

2006-01-01

Astronaut crew medical officers (CMO) aboard the International Space Station (ISS) receive 40 hours of medical training during the 18 months preceding each mission. Part of this training ilncludes twoperson cardiopulmonary resuscitation (CPR) per training guidelines from the American Heart Association (AHA). Recent studies concluded that the use of metronomic tones improves the coordination of CPR by trained clinicians. Similar data for bystander or "trained lay people" (e.g. CMO) performance of CPR (BCPR) have been limited. The purpose of this study was to evailuate whether use of timing devices, such as audible metronomic tones, would improve BCPR perfomance by trained bystanders. Twenty pairs of bystanders trained in two-person BCPR performled BCPR for 4 minutes on a simulated cardiopulmonary arrest patient using three interventions: 1) BCPR with no timing devices, 2) BCPR plus metronomic tones for coordinating compression rate only, 3) BCPR with a timing device and metronome for coordinating ventilation and compression rates, respectively. Bystanders were evaluated on their ability to meet international and AHA CPR guidelines. Bystanders failed to provide the recommended number of breaths and number of compressions in the absence of a timing device and in the presence of audible metronomic tones for only coordinating compression rate. Bystanders using timing devices to coordinate both components of BCPR provided the reco number of breaths and were closer to providing the recommended number of compressions compared with the other interventions. Survey results indicated that bystanders preferred to use a metronome for delivery of compressions during BCPR. BCPR performance is improved by timing devices that coordinate both compressions and breaths.

Genomic instability, bystander effect, cytoplasmic irradiation and other phenomena that may achieve fame without fortune.

PubMed

Hall, E J

2001-01-01

The possible risk of induced malignancies in astronauts, as a consequence of the radiation environment in space, is a factor of concern for long term missions. Cancer risk estimates for high doses of low LET radiation are available from the epidemiological studies of the A-bomb survivors. Cancer risks at lower doses cannot be detected in epidemiological studies and must be inferred by extrapolation from the high dose risks. The standard setting bodies, such as the ICRP recommend a linear, no-threshold extrapolation of risks from high to low doses, but this is controversial. A study of mechanisms of carcinogenesis may shed some light on the validity of a linear extrapolation. The multi-step nature of carcinogenesis suggests that the role of radiation may be to induce a mutation leading to a mutator phenotype. High energy Fe ions, such as those encountered in space are highly effective in inducing genomic instability. Experiments involving the single particle microbeam have demonstrated a "bystander effect", ie a biological effect in cells not themselves hit, but in close proximity to those that are, as well as the induction of mutations in cells where only the cytoplasm, and not the nucleus, have been traversed by a charged particle. These recent experiments cast doubt on the validity of a simple linear extrapolation, but the data are so far fragmentary and conflicting. More studies are necessary. While mechanistic studies cannot replace epidemiology as a source of quantitative risk estimates, they may shed some light on the shape of the dose response relationship and therefore on the limitations of a linear extrapolation to low doses.

Genomic instability, bystander effect, cytoplasmic irradiation and other phenomena that may achieve fame without fortune

NASA Technical Reports Server (NTRS)

Hall, E. J.

2001-01-01

The possible risk of induced malignancies in astronauts, as a consequence of the radiation environment in space, is a factor of concern for long term missions. Cancer risk estimates for high doses of low LET radiation are available from the epidemiological studies of the A-bomb survivors. Cancer risks at lower doses cannot be detected in epidemiological studies and must be inferred by extrapolation from the high dose risks. The standard setting bodies, such as the ICRP recommend a linear, no-threshold extrapolation of risks from high to low doses, but this is controversial. A study of mechanisms of carcinogenesis may shed some light on the validity of a linear extrapolation. The multi-step nature of carcinogenesis suggests that the role of radiation may be to induce a mutation leading to a mutator phenotype. High energy Fe ions, such as those encountered in space are highly effective in inducing genomic instability. Experiments involving the single particle microbeam have demonstrated a "bystander effect", ie a biological effect in cells not themselves hit, but in close proximity to those that are, as well as the induction of mutations in cells where only the cytoplasm, and not the nucleus, have been traversed by a charged particle. These recent experiments cast doubt on the validity of a simple linear extrapolation, but the data are so far fragmentary and conflicting. More studies are necessary. While mechanistic studies cannot replace epidemiology as a source of quantitative risk estimates, they may shed some light on the shape of the dose response relationship and therefore on the limitations of a linear extrapolation to low doses.

Bystander Behavior in Bullying Situations: Basic Moral Sensitivity, Moral Disengagement and Defender Self-Efficacy

ERIC Educational Resources Information Center

Thornberg, Robert; Jungert, Tomas

2013-01-01

The aim of the present study was to investigate how basic moral sensitivity in bullying, moral disengagement in bullying and defender self-efficacy were related to different bystander behaviors in bullying. Therefore, we examined pathways that linked students' basic moral sensitivity, moral disengagement, and defender self-efficacy to different…

Effects of prior physical exertion on tolerance to hypoxia, orthostatic stress, and physical fatigue.

DOT National Transportation Integrated Search

1982-03-01

Ten healthy men, 20-35 years old, were tested for tolerance to hypoxia, orthostatic stress, and physical fatigue after a period of rest, and, on another occasion, after a period of physical exertion. Exertion consisted of four 10-min periods of pedal...

Preventing and Responding to Sexual Misconduct: Preliminary Efficacy of a Peer-Led Bystander Training Program for Preventing Sexual Misconduct and Reducing Heavy Drinking Among Collegiate Athletes.

PubMed

Morean, Meghan E; Darling, Nancy; Smit, Jessie; DeFeis, Jolie; Wergeles, Maya; Kurzer-Yashin, Dana; Custer, Kaitlyn

2018-06-01

Sexual misconduct occurs with disproportionate frequency on college campuses, and alcohol is involved in most sexual assaults. Importantly, collegiate athletes are at risk for both heavy drinking and sexual misconduct. Thus, the current study evaluated the efficacy of a novel, 2.5-hr, peer-facilitated, interactive, group-based bystander intervention program for student athletes that integrated information on sexual misconduct and risky drinking (Preventing and Responding to Sexual Misconduct [PRSM]). In all, 205 athletes completed 25-min surveys immediately before and after the training, and 76 (of 94 invited) completed a 3-month follow-up. Participating in the workshop was associated with significant increases in acknowledgment that sexual misconduct is a problem on campus, knowledge of where to get help if sexual misconduct occurs, knowledge about the college's procedures for addressing sexual misconduct, confidence that the college's procedures for addressing sexual misconduct are fair, bystander confidence, and engagement in a range of bystander activities. A significant decrease in rape myths also was observed. Participating in the workshop also produced changes in alcohol-related beliefs and behaviors. After participating in PRSM, athletes reported increased expectations that drinking alcohol can produce negative effects including aggression and acute intoxication. Participating in the workshop also was associated with significant reductions in drinking frequency, the total number of drinks consumed per month, the maximum drinks consumed in 24 hours, the frequency of binge-drinking episodes, and the experience of alcohol-related problems. In sum, the PRSM program evidenced preliminary efficacy as a program designed to increase prosocial bystander behavior and decrease high-risk drinking among collegiate athletes; changes in beliefs and behaviors consistent with reducing risk for sexual misconduct and problem drinking were observed after workshop participation

Using a Multimedia Social Marketing Campaign to Increase Active Bystanders on the College Campus

ERIC Educational Resources Information Center

Potter, Sharyn J.

2012-01-01

Objective: To evaluate the campus-wide administration of the Know Your Power bystander-oriented social marketing campaign. Participants: Undergraduate students at a public college were invited to participate in a public awareness survey before and after the 6-week campaign administration in February and March 2009. Methods: Pretest and posttests…

EGFR ligands exert diverging effects on male reproductive organs.

PubMed

Schneider, Marlon R; Gratao, Ana A; Dahlhoff, Maik; Boersma, Auke; Hrabé de Angelis, Martin; Hoang-Vu, Cuong; Wolf, Eckhard; Klonisch, Thomas

2010-02-01

While the EGFR and most of its ligands are expressed in the male reproductive tract, their functions in male reproduction are poorly understood. Interestingly, male transgenic mice overexpressing EGF are sterile, and transgenic mice overexpressing TGFA, another EGFR ligand, show an enlarged coagulation gland (anterior prostate) due to severe hyperplasia with focal dysplasia. We studied the male reproductive tract of transgenic mice overexpressing betacellulin (BTC-tg) under the control of a promoter conferring widespread transgene expression. Despite strong overexpression of BTC in different parts of the male reproductive tract, the gross appearance and histology of the reproductive organs of BTC-tg males were normal and the same were true for sperm parameters and the in vitro fertilization rate. Collectively, our findings demonstrate that excess of BTC exerts no deleterious effects on the structure or function of the male reproductive tract in mice and indicates unique, non-overlapping functions of specific EGFR ligands in male reproduction. Copyright 2009 Elsevier Inc. All rights reserved.

The Mediating Role of Self-Exertion on the Effects of Effort on Learning Virtues and Emotional Distress in Academic Failure in a Confucian Context

PubMed Central

Fwu, Bih-Jen; Chen, Shun-Wen; Wei, Chih-Fen; Wang, Hsiou-Huai

2017-01-01

Previous studies have found that in East Asian Confucian societies, hardworking students are often trapped in a dilemma of enjoying a positive moral image while suffering from emotional distress due to academic failure. This study intends to further explore whether the cultural-specific belief in self-exertion acts as a psychological mechanism to lessen these students’ negative emotions. A group of 288 college students in Taiwan were administered a questionnaire to record their responses to past academic failures. The results from structural equation modeling showed that self-exertion functioned as a mediator between the effects of effort on learning virtues and emotional distress. Self-exertion to fulfill one’s duty to oneself positively mediated the effect of effort on learning virtues, whereas self-exertion to fulfill one’s duty to one’s parents negatively mediated the effect of effort on emotional distress. Theoretical and cultural implications are further discussed. PMID:28119648

Significant improvement of the quality of bystander first aid using an expert system with a mobile multimedia device.

PubMed

Ertl, Lorenz; Christ, Frank

2007-08-01

Better quality bystander first-aid could improve outcome rates for emergency victims significantly. In this case-control study, we hypothesised that expert knowledge presented step-by-step to untrained helpers using a personal digital assistant (PDA), would improve the quality of bystanders basic life support. We confronted 101 lay-helpers with two standard emergency situations. (1) An unconscious trauma victim with severe bleeding. (2) Cardiopulmonary resuscitation (CPR). Performance was assessed using an Objective Structured Clinical Examination (OSCE). One group was supported by a PDA providing visual and audio instructions, whereas the control group acted only with their current knowledge. The expert system was programmed in HTML-code and displayed on the PDA's Internet browser. The maximum score obtainable was 24 points corresponding to optimal treatment. The control group without the PDA reached 14.8+/-3.5 (mean value+/-standard deviation), whereas the PDA supported group scored significantly higher (21.9+/-2.7, p<0.01). The difference in performance was measurable in all criteria tested and particularly notable in the items: placing in recovery position, airway management and quality of CPR. The PDA based expert system increased the performance of untrained helpers supplying emergency care significantly. Since Internet compatible mobile devices have become widely available, a significant quality improvement in bystander first-aid seems possible.

Synchrony and exertion during dance independently raise pain threshold and encourage social bonding

PubMed Central

Tarr, Bronwyn; Launay, Jacques; Cohen, Emma; Dunbar, Robin

2015-01-01

Group dancing is a ubiquitous human activity that involves exertive synchronized movement to music. It is hypothesized to play a role in social bonding, potentially via the release of endorphins, which are analgesic and reward-inducing, and have been implicated in primate social bonding. We used a 2 × 2 experimental design to examine effects of exertion and synchrony on bonding. Both demonstrated significant independent positive effects on pain threshold (a proxy for endorphin activation) and in-group bonding. This suggests that dance which involves both exertive and synchronized movement may be an effective group bonding activity. PMID:26510676

Effect of Stimulant Medication Use by Children with ADHD on Heart Rate and Perceived Exertion

ERIC Educational Resources Information Center

Mahon, Anthony D.; Woodruff, Megan E.; Horn, Mary P.; Marjerrison, Andrea D.; Cole, Andrew S.

2012-01-01

The effect of stimulant medication use by children with attention deficit/hyperactivity disorder (ADHD) on the rating of perceived exertion (RPE)--heart rate (HR) relationship was examined. Children with ADHD (n = 20; 11.3 [plus or minus] 1.8 yrs) and children without ADHD (n = 25; 11.2 [plus or minus] 2.1 yrs) were studied. Children with ADHD…

The effect of vocal and instrumental music on cardio respiratory variables, energy expenditure and exertion levels during sub maximal treadmill exercise.

PubMed

Savitha, D; Sejil, T V; Rao, Shwetha; Roshan, C J; Roshan, C J

2013-01-01

The purpose of the study was to investigate the effect of vocal and instrumental music on various physiological parameters during submaximal exercise. Each subject underwent three sessions of exercise protocol without music, with vocal music, and instrumental versions of same piece of music. The protocol consisted of 10 min treadmill exercise at 70% HR(max) and 20 min of recovery. Minute to minute heart rate and breath by breath recording of respiratory parameters, rate of energy expenditure and perceived exertion levels were measured. Music, irrespective of the presence or absence of lyrics, enabled the subjects to exercise at a significantly lower heart rate and oxygen consumption, reduced the metabolic cost and perceived exertion levels of exercise (P < 0.05). There was faster recovery of systolic and diastolic blood pressures and exertion levels during the post exercise period. Music having a relaxant effect could have probably increased the parasympathetic activation leading to these effects.

Fluoxetine Exerts Age-Dependent Effects on Behavior and Amygdala Neuroplasticity in the Rat

PubMed Central

Homberg, Judith R.; Olivier, Jocelien D. A.; Blom, Tom; Arentsen, Tim; van Brunschot, Chantal; Schipper, Pieter; Korte-Bouws, Gerdien; van Luijtelaar, Gilles; Reneman, Liesbeth

2011-01-01

The selective serotonin reuptake inhibitor (SSRI) Prozac® (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and thereby may have harmful effects in adolescents. Here we treated adolescent and adult rats chronically with fluoxetine (12 mg/kg) at postnatal day (PND) 25 to 46 and from PND 67 to 88, respectively, and tested the animals 7–14 days after the last injection when (nor)fluoxetine in blood plasma had been washed out, as determined by HPLC. Plasma (nor)fluoxetine levels were also measured 5 hrs after the last fluoxetine injection, and matched clinical levels. Adolescent rats displayed increased behavioral despair in the forced swim test, which was not seen in adult fluoxetine treated rats. In addition, beneficial effects of fluoxetine on wakefulness as measured by electroencephalography in adults was not seen in adolescent rats, and age-dependent effects on the acoustic startle response and prepulse inhibition were observed. On the other hand, adolescent rats showed resilience to the anorexic effects of fluoxetine. Exploratory behavior in the open field test was not affected by fluoxetine treatment, but anxiety levels in the elevated plus maze test were increased in both adolescent and adult fluoxetine treated rats. Finally, in the amygdala, but not the dorsal raphe nucleus and medial prefrontal cortex, the number of PSA-NCAM (marker for synaptic remodeling) immunoreactive neurons was increased in adolescent rats, and decreased in adult rats, as a consequence of chronic fluoxetine treatment. No fluoxetine-induced changes in 5-HT1A receptor immunoreactivity were observed. In conclusion, we show that fluoxetine exerts both harmful and beneficial age-dependent effects on depressive behavior, body weight and wakefulness, which may relate, in part, to differential fluoxetine

20 CFR 220.132 - Physical exertion requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Physical exertion requirements. 220.132... ACT DETERMINING DISABILITY Vocational Considerations § 220.132 Physical exertion requirements. To determine the physical exertion requirements of work in the national economy, jobs are classified as...

20 CFR 220.132 - Physical exertion requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Physical exertion requirements. 220.132... ACT DETERMINING DISABILITY Vocational Considerations § 220.132 Physical exertion requirements. To determine the physical exertion requirements of work in the national economy, jobs are classified as...

20 CFR 220.132 - Physical exertion requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Physical exertion requirements. 220.132... ACT DETERMINING DISABILITY Vocational Considerations § 220.132 Physical exertion requirements. To determine the physical exertion requirements of work in the national economy, jobs are classified as...

20 CFR 220.132 - Physical exertion requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Physical exertion requirements. 220.132... ACT DETERMINING DISABILITY Vocational Considerations § 220.132 Physical exertion requirements. To determine the physical exertion requirements of work in the national economy, jobs are classified as...

20 CFR 220.132 - Physical exertion requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Physical exertion requirements. 220.132... ACT DETERMINING DISABILITY Vocational Considerations § 220.132 Physical exertion requirements. To determine the physical exertion requirements of work in the national economy, jobs are classified as...

Viewing an ultra-brief chest compression only video improves some measures of bystander CPR performance and responsiveness at a mass gathering event.

PubMed

Beskind, Daniel L; Stolz, Uwe; Thiede, Rebecca; Hoyer, Riley; Robertson, Whitney; Brown, Jeffrey; Ludgate, Melissa; Tiutan, Timothy; Shane, Romy; McMorrow, Deven; Pleasants, Michael; Kern, Karl B; Panchal, Ashish R

2017-09-01

CPR training at mass gathering events is an important part of health initiatives to improve cardiac arrest survival. However, it is unclear whether training lay bystanders using an ultra-brief video at a mass gathering event improves CPR quality and responsiveness. To determine if showing a chest-compression only (CCO) Ultra-Brief Video (UBV) at a mass gathering event is effective in teaching lay bystanders CCO-CPR. Prospective control trial in adults (age >18) who attended either a women's University of Arizona or a men's Phoenix Suns basketball game. Participants were evaluated using a standardized cardiac arrest scenario with Laerdal Skillreporter™ mannequins. CPR responsiveness (calling 911, time to calling 911, starting compressions within two minutes) and quality (compression rate, depth, hands-off time) were assessed for participants and data collected at Baseline and Post-intervention. Different participants were tested before and after the exposure of the UBV. Data were analyzed via the intention to treat principle using logistic regression for binary outcomes and median regression for continuous outcomes, controlling for clustering by venue. A total of 96 people were consented (Baseline=45; Post intervention=51). CPR responsiveness post intervention improved with faster time to calling 911 (s) and time to starting compressions (sec). Likewise, CPR quality improved with deeper compressions and improved hands-off time. Showing a UBV at a mass gathering sporting event is associated with improved CPR responsiveness and performance for lay bystanders. This data provides further support for the use of mass media interventions. Copyright © 2017 Elsevier B.V. All rights reserved.

Sticks, Stones, and Stigma: Student Bystander Behavior in Response to Hearing the Word "Retard"

ERIC Educational Resources Information Center

Albert, Avery B.; Jacobs, Holly E.; Siperstein, Gary N.

2016-01-01

The present study explored the prevalence of the r-word in schools and students' bystander behavior in response to hearing the word. In total, 2,297 students from 12 high schools across the country participated in this study. Results revealed the r-word was used frequently among high school students, most often toward individuals without…

Gamma-H2AX as a biomarker of DNA damage induced by ionizing radiation in targeted and bystander human artificial skin models and peripheral blood lymphocytes

NASA Astrophysics Data System (ADS)

Redon, Christophe; Dickey, Jennifer; Bonner, William; Sedelnikova, Olga

30 min after irradiation and then declined at a relatively steady pace as the cell repaired the DNA damage. Radiation effects were still detectable after 48 hrs for doses greater than 1 Gy and remained linear to initial dose. Activated bystander lymphocytes cultured with media from irradiated lymphocytes exhibited a two-fold increased damage response as seen by gamma- H2AX formation. The effect reached a maximum 3 hrs post-exposure and was retained for over 24 hrs. Thus, detection of gamma-H2AX formation to determine DNA damage in a minimally invasive skin test and a non-invasive blood test could be useful and promising tools to analyze direct and indirect effects of radiation exposure.

Effectiveness of cold water immersion for treating exertional heat stress when immediate response is not possible.

PubMed

Flouris, A D; Friesen, B J; Carlson, M J; Casa, D J; Kenny, G P

2015-06-01

Immediate treatment with cold water immersion (CWI) is the gold standard for exertional heatstroke. In the field, however, treatment is often delayed due to delayed paramedic response and/or inaccurate diagnosis. We examined the effect of treatment (reduction of rectal temperature to 37.5 °C) delays of 5, 20, and 40 min on core cooling rates in eight exertionally heat-stressed (40.0 °C rectal temperature) individuals. We found that rectal temperature was elevated above baseline (P < 0.05) at the end of all delay periods (5 min: 40.08 ± 0.32; 20 min: 39.92 ± 0.40; 40 min: 39.57 ± 0.29 °C). Mean arterial pressure was reduced (P < 0.05) below baseline (92 ± 1.8 mm Hg) after all delay periods (5 min: 75 ± 2.6; 20 min: 74 ± 1.7; 40 min: 70 ± 2.1 mm Hg; P > 0.05). Rectal core cooling rates were similar among conditions (5 min: 0.20 ± 0.01; 20 min: 0.17 ± 0.02; 40 min: 0.17 ± 0.01 °C/min; P > 0.05). The rectal temperature afterdrop following CWI was similar across conditions (5 min: 35.95; 20 min: 35.61; 40 min: 35.87 °C; P > 0.05). We conclude that the effectiveness of 2 °C CWI as a treatment for exertional heat stress remains high even when applied with a delay of 40 min. Therefore, our results support that CWI is the most appropriate treatment for exertional heatstroke as it is capable of quickly reversing hyperthermia even when treatment is commenced with a significant delay. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Bystanders Matter: Associations between Reinforcing, Defending, and the Frequency of Bullying Behavior in Classrooms

ERIC Educational Resources Information Center

Salmivalli, Christina; Voeten, Marinus; Poskiparta, Elisa

2011-01-01

This study investigated whether the bystanders' behaviors (reinforcing the bully vs. defending the victim) in bullying situations are related to the frequency of bullying in a classroom. The sample consisted of 6,764 primary school children from Grades 3 to 5 (9-11 years of age), who were nested within 385 classrooms in 77 schools. The students…

Virtual exertions: evoking the sense of exerting forces in virtual reality using gestures and muscle activity.

PubMed

Chen, Karen B; Ponto, Kevin; Tredinnick, Ross D; Radwin, Robert G

2015-06-01

This study was a proof of concept for virtual exertions, a novel method that involves the use of body tracking and electromyography for grasping and moving projections of objects in virtual reality (VR). The user views objects in his or her hands during rehearsed co-contractions of the same agonist-antagonist muscles normally used for the desired activities to suggest exerting forces. Unlike physical objects, virtual objects are images and lack mass. There is currently no practical physically demanding way to interact with virtual objects to simulate strenuous activities. Eleven participants grasped and lifted similar physical and virtual objects of various weights in an immersive 3-D Cave Automatic Virtual Environment. Muscle activity, localized muscle fatigue, ratings of perceived exertions, and NASA Task Load Index were measured. Additionally, the relationship between levels of immersion (2-D vs. 3-D) was studied. Although the overall magnitude of biceps activity and workload were greater in VR, muscle activity trends and fatigue patterns for varying weights within VR and physical conditions were the same. Perceived exertions for varying weights were not significantly different between VR and physical conditions. Perceived exertion levels and muscle activity patterns corresponded to the assigned virtual loads, which supported the hypothesis that the method evoked the perception of physical exertions and showed that the method was promising. Ultimately this approach may offer opportunities for research and training individuals to perform strenuous activities under potentially safer conditions that mimic situations while seeing their own body and hands relative to the scene. © 2014, Human Factors and Ergonomics Society.

Tell the Teacher or Tell the Bully Off: Children's Strategy Production for Bystanders to Bullying

ERIC Educational Resources Information Center

Rock, Patrick F.; Baird, Jodie A.

2012-01-01

Although children's reticence to intervene as bystanders to bullying is well established, the reasons for their inaction remain unclear. One possibility is that they are incapable of generating appropriate response strategies in these situations. This study examined the number and type of strategies children (N = 104, 6-11 years) could generate…

Multiple Mechanisms of Anti-Cancer Effects Exerted by Astaxanthin

PubMed Central

Zhang, Li; Wang, Handong

2015-01-01

Astaxanthin (ATX) is a xanthophyll carotenoid which has been approved by the United States Food and Drug Administration (USFDA) as food colorant in animal and fish feed. It is widely found in algae and aquatic animals and has powerful anti-oxidative activity. Previous studies have revealed that ATX, with its anti-oxidative property, is beneficial as a therapeutic agent for various diseases without any side effects or toxicity. In addition, ATX also shows preclinical anti-tumor efficacy both in vivo and in vitro in various cancer models. Several researches have deciphered that ATX exerts its anti-proliferative, anti-apoptosis and anti-invasion influence via different molecules and pathways including signal transducer and activator of transcription 3 (STAT3), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and peroxisome proliferator-activated receptor gamma (PPARγ). Hence, ATX shows great promise as chemotherapeutic agents in cancer. Here, we review the rapidly advancing field of ATX in cancer therapy as well as some molecular targets of ATX. PMID:26184238

Uninfected Bystander Cells Impact the Measurement of HIV-Specific Antibody-Dependent Cellular Cytotoxicity Responses.

PubMed

Richard, Jonathan; Prévost, Jérémie; Baxter, Amy E; von Bredow, Benjamin; Ding, Shilei; Medjahed, Halima; Delgado, Gloria G; Brassard, Nathalie; Stürzel, Christina M; Kirchhoff, Frank; Hahn, Beatrice H; Parsons, Matthew S; Kaufmann, Daniel E; Evans, David T; Finzi, Andrés

2018-03-20

The conformation of the HIV-1 envelope glycoprotein (Env) substantially impacts antibody recognition and antibody-dependent cellular cytotoxicity (ADCC) responses. In the absence of the CD4 receptor at the cell surface, primary Envs sample a "closed" conformation that occludes CD4-induced (CD4i) epitopes. The virus controls CD4 expression through the actions of Nef and Vpu accessory proteins, thus protecting infected cells from ADCC responses. However, gp120 shed from infected cells can bind to CD4 present on uninfected bystander cells, sensitizing them to ADCC mediated by CD4i antibodies (Abs). Therefore, we hypothesized that these bystander cells could impact the interpretation of ADCC measurements. To investigate this, we evaluated the ability of antibodies to CD4i epitopes and broadly neutralizing Abs (bNAbs) to mediate ADCC measured by five ADCC assays commonly used in the field. Our results indicate that the uninfected bystander cells coated with gp120 are efficiently recognized by the CD4i ligands but not the bNabs. Consequently, the uninfected bystander cells substantially affect in vitro measurements made with ADCC assays that fail to identify responses against infected versus uninfected cells. Moreover, using an mRNA flow technique that detects productively infected cells, we found that the vast majority of HIV-1-infected cells in in vitro cultures or ex vivo samples from HIV-1-infected individuals are CD4 negative and therefore do not expose significant levels of CD4i epitopes. Altogether, our results indicate that ADCC assays unable to differentiate responses against infected versus uninfected cells overestimate responses mediated by CD4i ligands. IMPORTANCE Emerging evidence supports a role for antibody-dependent cellular cytotoxicity (ADCC) in protection against HIV-1 transmission and disease progression. However, there are conflicting reports regarding the ability of nonneutralizing antibodies targeting CD4-inducible (CD4i) Env epitopes to mediate

Exercise, physical activity, and exertion over the business cycle.

PubMed

Colman, Gregory; Dave, Dhaval

2013-09-01

Shifts in time and income constraints over economic expansions and contractions would be expected to affect individuals' behaviors. We explore the impact of the business cycle on individuals' exercise, time use, and total physical exertion, utilizing information on 112,000 individual records from the 2003-2010 American Time Use Surveys. In doing so, we test a key causal link that has been hypothesized in the relation between unemployment and health, but not heretofore assessed. Using more precise measures of exercise (and other activities) than previous studies, we find that as work-time decreases during a recession, recreational exercise, TV-watching, sleeping, childcare, and housework increase. This, however, does not compensate for the decrease in work-related exertion due to job-loss, and total physical exertion declines. These effects are strongest among low-educated men, which is validating given that employment in the Great Recession has declined most within manufacturing, mining, and construction. We also find evidence of intra-household spillover effects, wherein individuals respond to shifts in spousal employment conditional on their own labor supply. The decrease in total physical activity during recessions is especially problematic for vulnerable populations concentrated in boom-and-bust industries, and may have longer-term effects on obesity and related health outcomes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fruit extract of the medicinal plant Crataegus oxyacantha exerts genotoxic and mutagenic effects in cultured cells.

PubMed

de Quadros, Ana Paula Oliveira; Mazzeo, Dania Elisa Christofoletti; Marin-Morales, Maria Aparecida; Perazzo, Fábio Ferreira; Rosa, Paulo Cesar Pires; Maistro, Edson Luis

2017-01-01

Crataegus oxyacantha, a plant of the Rosaceae family also known "English hawthorn, haw, maybush, or whitethorn," has long been used for medicinal purposes such as digestive disorders, hyperlipidemia, dyspnea, inducing diuresis, and preventing kidney stones. However, the predominant use of this plant has been to treat cardiovascular disorders. Due to a lack of studies on the genotoxicity of C. oxyacantha, this investigation was undertaken to determine whether its fruit extract exerts cytotoxic, genotoxic, or clastogenic/aneugenic effects in leukocytes and HepG2 (liver hepatocellular carcinoma) cultured human cells, or mutagenic effects in TA100 and TA98 strains of Salmonella typhimurium bacterium. Genotoxicity analysis showed that the extract produced no marked genotoxic effects at concentrations of 2.5 or 5 µg/ml in either cell type; however, at concentrations of 10 µg/ml or higher significant DNA damage was detected. The micronucleus test also demonstrated that concentrations of 10 µg/ml or higher produced clastogenic/aneugenic responses. In the Ames test, the extract induced mutagenic effects in TA98 strain of S. typhimurium with metabolic activation at all tested concentrations (2.5 to 500 µg/ml). Data indicate that, under certain experimental conditions, the fruit extract of C. oxyacantha exerts genotoxic and clastogenic/aneugenic effects in cultured human cells, and with metabolism mutagenicity occurs in bacteria cells.

The Effects of Cell Phone Conversations on the Attention and Memory of Bystanders

PubMed Central

Galván, Veronica V.; Vessal, Rosa S.; Golley, Matthew T.

2013-01-01

The pervasive use of cell phones impacts many people–both cell phone users and bystanders exposed to conversations. This study examined the effects of overhearing a one-sided (cell phone) conversation versus a two-sided conversation on attention and memory. In our realistic design, participants were led to believe they were participating in a study examining the relationship between anagrams and reading comprehension. While the participant was completing an anagram task, the researcher left the room and participants overheard a scripted conversation, either two confederates talking with each other or one confederate talking on a cell phone. Upon the researcher’s return, the participant took a recognition memory task with words from the conversation, and completed a questionnaire measuring the distracting nature of the conversation. Participants who overheard the one-sided conversation rated the conversation as significantly higher in distractibility than those who overheard the two-sided conversation. Also, participants in the one-sided condition scored higher on the recognition task. In particular they were more confident and accurate in their responses to words from the conversation than participants in the two-sided condition. However, participants’ scores on the anagram task were not significantly different between conditions. As in real world situations, individual participants could pay varying amounts of attention to the conversation since they were not explicitly instructed to ignore it. Even though the conversation was irrelevant to the anagram task and contained less words and noise, one-sided conversations still impacted participants’ self-reported distractibility and memory, thus showing people are more attentive to cell phone conversations than two-sided conversations. Cell phone conversations may be a common source of distraction causing negative consequences in workplace environments and other public places. PMID:23516514

The effects of cell phone conversations on the attention and memory of bystanders.

PubMed

Galván, Veronica V; Vessal, Rosa S; Golley, Matthew T

2013-01-01

The pervasive use of cell phones impacts many people-both cell phone users and bystanders exposed to conversations. This study examined the effects of overhearing a one-sided (cell phone) conversation versus a two-sided conversation on attention and memory. In our realistic design, participants were led to believe they were participating in a study examining the relationship between anagrams and reading comprehension. While the participant was completing an anagram task, the researcher left the room and participants overheard a scripted conversation, either two confederates talking with each other or one confederate talking on a cell phone. Upon the researcher's return, the participant took a recognition memory task with words from the conversation, and completed a questionnaire measuring the distracting nature of the conversation. Participants who overheard the one-sided conversation rated the conversation as significantly higher in distractibility than those who overheard the two-sided conversation. Also, participants in the one-sided condition scored higher on the recognition task. In particular they were more confident and accurate in their responses to words from the conversation than participants in the two-sided condition. However, participants' scores on the anagram task were not significantly different between conditions. As in real world situations, individual participants could pay varying amounts of attention to the conversation since they were not explicitly instructed to ignore it. Even though the conversation was irrelevant to the anagram task and contained less words and noise, one-sided conversations still impacted participants' self-reported distractibility and memory, thus showing people are more attentive to cell phone conversations than two-sided conversations. Cell phone conversations may be a common source of distraction causing negative consequences in workplace environments and other public places.

H-Ras Exerts Opposing Effects on Type I Interferon Responses Depending on Its Activation Status.

PubMed

Chen, Guann-An; Lin, Yun-Ru; Chung, Hai-Ting; Hwang, Lih-Hwa

2017-01-01

Using shRNA high-throughput screening, we identified H-Ras as a regulator of antiviral activity, whose depletion could enhance Sindbis virus replication. Further analyses indicated that depletion of H-Ras results in a robust increase in vesicular stomatitis virus infection and a decrease in Sendai virus (SeV)-induced retinoic acid-inducible gene-I-like receptor (RLR) signaling. Interestingly, however, ectopic expression of wild-type H-Ras results in a biphasic mode of RLR signaling regulation: while low-level expression of H-Ras enhances SeV-induced RLR signaling, high-level expression of H-Ras significantly inhibits this signaling. The inhibitory effects correlate with the activation status of H-Ras. As a result, oncogenic H-Ras, H-RasV12, strongly inhibits SeV-induced IFN-β promoter activity and type I interferon signaling. Conversely, the positive effects exerted by H-Ras on RLR signaling are independent of its signaling activity, as a constitutively inactive form of H-Ras, H-RasN17, also positively regulates RLR signaling. Mechanistically, we demonstrate that depletion of H-Ras reduces the formation of MAVS-TNF receptor-associated factor 3 signaling complexes. These results reveal that the H-Ras protein plays a role in promoting MAVS signalosome assembly in the mitochondria, whereas oncogenic H-Ras exerts a negative effect on type I IFN responses.

A Mixed Methods Evaluation of the "Aged-Up" STAC Bullying Bystander Intervention for High School Students

ERIC Educational Resources Information Center

Johnston, April D.; Midgett, Aida; Doumas, Diana M.; Moody, Steve

2018-01-01

This mixed methods study assessed the appropriateness of an "aged-up," brief bullying bystander intervention (STAC) and explored the lived experiences of high school students trained in the program. Quantitative results included an increase in knowledge and confidence to intervene in bullying situations, awareness of bullying, and use of…

Classroom relationship qualities and social-cognitive correlates of defending and passive bystanding in school bullying in Sweden: A multilevel analysis.

PubMed

Thornberg, Robert; Wänström, Linda; Hong, Jun Sung; Espelage, Dorothy L

2017-08-01

Using the social-ecological and social cognitive theories as integrated guiding frameworks, the present study examined whether moral disengagement and defender self-efficacy at the individual level, and moral disengagement, quality of teacher-student relationships and quality of student-student relationships at the classroom level were associated with passive bystanding and defending in bullying situations. Participants were 900 Swedish students from 43 classrooms, ranging in age from 9 to 13years. Multilevel regression analyses revealed that passive reactions by bystanders were associated with greater moral disengagement and less defender self-efficacy. Defending, in turn, was associated with less moral disengagement and greater defender self-efficacy and classroom student-student relationship quality. Furthermore, students who scored high in moral disengagement were even less prone to defend victims when the classroom student-student relationship quality was low, but more prone to act as defenders when the classroom student-student relationship quality was high. In addition, the negative association between defender self-efficacy and passive bystanding was stronger both in classrooms with higher student-student relationship quality and in those with lower class moral disengagement. Implications for prevention are discussed. Copyright © 2017 Society for the Study of School Psychology. All rights reserved.

Coach Expectations About Off-Field Conduct and Bystander Intervention by U.S. College Football Players to Prevent Inappropriate Sexual Behavior.

PubMed

Kroshus, Emily; Paskus, Tom; Bell, Lydia

2015-09-21

The objective of the present study was to assess whether there is a positive association between expectations about off-field conduct set by the team coach and the likelihood that college football players intend to engage as prosocial bystanders in the prevention of what they consider to be inappropriate sexual behavior. In a sample of U.S. collegiate football players (N = 3,281), a path analysis model tested the association between coach expectations, perceived likelihood of discipline for off-field transgressions, and likelihood of intending to intervene to prevent inappropriate sexual behavior. Mediation of these relationships by the athlete's sense of exploitative entitlement and their attitudes about intervening were also assessed. Findings supported the hypothesized relationships, with expectations and discipline associated with bystander intentions both directly and indirectly through the mediating pathways of entitlement and attitudes about intervening. These findings provide evidence about the important role that sports team coaches can play in encouraging bystander intervention by clarifying expectations and consequences for conduct off the field of play. Athletic departments can provide a framework within which coaches are informed about the importance of setting and enforcing standards for off-field behavior, and are appropriately incentivized to do so. © The Author(s) 2015.

Nitrite exerts antioxidant effects, inhibits the mTOR pathway and reverses hypertension-induced cardiac hypertrophy.

PubMed

Guimaraes, Danielle A; Dos Passos, Madla A; Rizzi, Elen; Pinheiro, Lucas C; Amaral, Jefferson H; Gerlach, Raquel F; Castro, Michele M; Tanus-Santos, Jose E

2018-05-20

Cardiac hypertrophy is a common consequence of chronic hypertension and leads to heart failure and premature death. The anion nitrite is now considered as a bioactive molecule able to exert beneficial cardiovascular effects. Previous results showed that nitrite attenuates hypertension-induced increases in reactive oxygen species (ROS) production in the vasculature. Whether antioxidant effects induced by nitrite block critical signaling pathways involved in cardiac hypertrophy induced by hypertension has not been determined yet. The Akt/mTOR signaling pathway is responsible to activate protein synthesis during cardiac remodeling and is activated by increased ROS production, which is commonly found in hypertension. Here, we investigated the effects of nitrite treatment on cardiac remodeling and activation of this hypertrophic signaling pathway in 2 kidney-1 clip (2K1C) hypertension. Sham and 2K1C rats were treated with oral nitrite at 1 or 15 mg/kg for four weeks. Nitrite treatment (15 mg/kg) reduced systolic blood pressure and decreased ROS production in the heart tissue from hypertensive rats. This nitrite dose also blunted hypertension-induced activation of mTOR pathway and cardiac hypertrophy. While the lower nitrite dose (1 mg/kg) did not affect blood pressure, it exerted antioxidant effects and tended to attenuate mTOR pathway activation and cardiac hypertrophy induced by hypertension. Our findings provide strong evidence that nitrite treatment decreases cardiac remodeling induced by hypertension as a result of its antioxidant effects and downregulation of mTOR signaling pathway. This study may help to establish nitrite as an effective therapy in hypertension-induced cardiac hypertrophic remodeling. Copyright © 2018 Elsevier Inc. All rights reserved.

Bystanders' Reactions to Bullying: A Cross-Cultural Analysis of Personal Correlates among Italian and Singaporean Students

ERIC Educational Resources Information Center

Pozzoli, Tiziana; Ang, Rebecca P.; Gini, Gianluca

2012-01-01

This study examined the role of attitudes against bullying and perceived peer pressure for intervention in explaining defending the victim and passive bystanding behavior in bullying. Participants were 1031 school-age children from two culturally diverse settings, namely Italy and Singapore, which are similar on several dimensions (e.g., quality…

When exercise causes exertional rhabdomyolysis.

PubMed

Furman, Janet

2015-04-01

Exertional rhabdomyolysis is a clinical condition caused by intense, repetitive exercise or a sudden increase in exercise in an untrained person, although rhabdomyolysis can occur in trained athletes. In many cases, the presentation of early, uncomplicated rhabdomyolysis is subtle, but serious complications such as renal failure, compartment syndrome, and dysrhythmias may arise if severe exertional rhabdomyolysis is undiagnosed or untreated. Management is further complicated by the lack of concrete management guidelines for treating rhabdomyolysis and returning patients to activity.

Mangiferin inhibits hippocampal NLRP3 inflammasome and exerts antidepressant effects in a chronic mild stress mice model.

PubMed

Cao, Changfu; Su, Meiqing; Zhou, Feng

2017-08-01

A growing body of evidence suggests that inflammation may contribute toward the development of major depressive disorder. Mangiferin, a glucosylxanthone from Mangifera indica, exerts a number of biological actions, including anti-inflammatory effects. Although mangiferin has potential antidepressant activity, the mechanisms of this effect remain unclear. The present study investigated the effects of mangiferin on behavioral changes and inflammatory responses induced by chronic mild stress (CMS) in mice. We found that treatment with mangiferin for 3 weeks significantly increased the body weight of mice and ameliorated CMS-induced behavioral abnormalities by increasing sucrose consumption, improving locomotor activities, and decreasing the immobility time in the forced-swimming test and tail-suspension test. It also suppressed increased serum corticosterone levels in CMS mice. In response to CMS induction, the NLR family, pyrin domain containing 3 (NLRP3) inflammasome was activated and interleukin (IL)-1β and IL-18 levels were increased in the mouse hippocampus. Mangiferin treatment downregulated the expression of NLRP3, the adaptor protein ASC, and caspase-1, which subsequently reduced the production of IL-1β and IL-18 in CMS mice. In sum, our results indicate that mangiferin exerts antidepressant-like effects in CMS model, possibly by inhibiting IL-1β production and NLRP3 inflammasome expression.

Tramadol and propentofylline coadministration exerted synergistic effects on rat spinal nerve ligation-induced neuropathic pain.

PubMed

Zhang, Jin; Wu, Dan; Xie, Cheng; Wang, Huan; Wang, Wei; Zhang, Hui; Liu, Rui; Xu, Li-Xian; Mei, Xiao-Peng

2013-01-01

Neuropathic pain is an intractable clinical problem. Drug treatments such as tramadol have been reported to effectively decrease neuropathic pain by inhibiting the activity of nociceptive neurons. It has also been reported that modulating glial activation could also prevent or reverse neuropathic pain via the administration of a glial modulator or inhibitor, such as propentofylline. Thus far, there has been no clinical strategy incorporating both neuronal and glial participation for treating neuropathic pain. Therefore, the present research study was designed to assess whether coadministration of tramadol and propentofylline, as neuronal and glial activation inhibitors, respectively, would exert a synergistic effect on the reduction of rat spinal nerve ligation (SNL)-induced neuropathic pain. Rats underwent SNL surgery to induce neuropathic pain. Pain behavioral tests were conducted to ascertain the effect of drugs on SNL-induced mechanical allodynia with von-Frey hairs. Proinflammatory factor interleukin-1β (IL-1β) expression was also detected by Real-time RT-PCR. Intrathecal tramadol and propentofylline administered alone relieved SNL-induced mechanical allodynia in a dose-dependent manner. Tramadol and propentofylline coadministration exerted a more potent effect in a synergistic and dose dependent manner than the intrathecal administration of either drug alone. Real-time RT-PCR demonstrated IL-1β up-expression in the ipsilateral spinal dorsal horn after the lesion, which was significantly decreased by tramadol and propentofylline coadministration. Inhibiting proinflammatory factor IL-1β contributed to the synergistic effects of tramadol and propentofylline coadministration on rat peripheral nerve injury-induced neuropathic pain. Thus, our study provided a rationale for utilizing a novel strategy for treating neuropathic pain by blocking the proinflammatory factor related pathways in the central nervous system.

Tramadol and Propentofylline Coadministration Exerted Synergistic Effects on Rat Spinal Nerve Ligation-Induced Neuropathic Pain

PubMed Central

Wang, Huan; Wang, Wei; Zhang, Hui; Liu, Rui; Xu, Li-Xian; Mei, Xiao-Peng

2013-01-01

Neuropathic pain is an intractable clinical problem. Drug treatments such as tramadol have been reported to effectively decrease neuropathic pain by inhibiting the activity of nociceptive neurons. It has also been reported that modulating glial activation could also prevent or reverse neuropathic pain via the administration of a glial modulator or inhibitor, such as propentofylline. Thus far, there has been no clinical strategy incorporating both neuronal and glial participation for treating neuropathic pain. Therefore, the present research study was designed to assess whether coadministration of tramadol and propentofylline, as neuronal and glial activation inhibitors, respectively, would exert a synergistic effect on the reduction of rat spinal nerve ligation (SNL)-induced neuropathic pain. Rats underwent SNL surgery to induce neuropathic pain. Pain behavioral tests were conducted to ascertain the effect of drugs on SNL-induced mechanical allodynia with von-Frey hairs. Proinflammatory factor interleukin-1β (IL-1β) expression was also detected by Real-time RT-PCR. Intrathecal tramadol and propentofylline administered alone relieved SNL-induced mechanical allodynia in a dose-dependent manner. Tramadol and propentofylline coadministration exerted a more potent effect in a synergistic and dose dependent manner than the intrathecal administration of either drug alone. Real-time RT-PCR demonstrated IL-1β up-expression in the ipsilateral spinal dorsal horn after the lesion, which was significantly decreased by tramadol and propentofylline coadministration. Inhibiting proinflammatory factor IL-1β contributed to the synergistic effects of tramadol and propentofylline coadministration on rat peripheral nerve injury-induced neuropathic pain. Thus, our study provided a rationale for utilizing a novel strategy for treating neuropathic pain by blocking the proinflammatory factor related pathways in the central nervous system. PMID:24009718

Exertion and acute coronary artery injury.

PubMed

Black, A; Black, M M; Gensini, G

1975-12-01

Twelve cases of myocardial infarction as related to strenuous exertion are presented with the pathological findings in several of these cases. Three cases with coronary arteriography are also presented. The pathology of coronary arteriosclerotic plaques and the vulnerability to acute injury is reviewed and discussed. It is concluded that strenuous exertion can cause acute injury to coronary artery plaques due to the unusual stressful whip-like action to which coronary arteries are subject. These injuries may initiate as cracks in the plaques or subintimal hemorrhages and proceed to coronary occlusion and ultimate myocardial infarction. With this concept in mind we use the term of "crack in the plaque" (Black's Crack in the Plaque) to account for the sudden appearance of clinical coronary artery disease appearing during or shortly after exertion, or other stressful situations in patients without previous existing evidence of clinical coronary artery disease. This could also account for exacerbation of symptoms or death occurring after exertion in previously quiescent asymptomatic known coronary artery disease subjects. This concept may explain some of the puzzling features of coronary disease.

The DHEA metabolite 7β-hydroxy-epiandrosterone exerts anti-estrogenic effects on breast cancer cell lines.

PubMed

Sandra, Niro; Ester, Pereira; Marie-Agnès, Pélissier; Robert, Morfin; Olivier, Hennebert

2012-04-01

7β-Hydroxy-epiandrosterone (7β-OH-EpiA), an endogenous androgenic derivative of dehydroepiandrosterone, has previously been shown to exert anti-inflammatory action in vitro and in vivo via a shift from prostaglandin E2 (PGE2) to 15-deoxy-Δ(12,14)-PGJ2 production. This modulation in prostaglandin production was obtained with low concentrations of 7β-OH-EpiA (1-100nM) and suggested that it might act through a specific receptor. Inflammation and prostaglandin synthesis is important in the development and survival of estrogen-dependent mammary cancers. Estrogen induced PGE2 production and cell proliferation via its binding to estrogen receptors (ERs) in these tumors. Our objective was to test the effects of 7β-OH-EpiA on the proliferation (by counting with trypan blue exclusion), cell cycle and cell apoptosis (by flow cytometry) of breast cancer cell lines MCF-7 (ERα+, ERβ+, G-protein coupled receptor 30: GPR30+) and MDA-MB-231 (ERα-, ERβ+, GPR30+) and to identify a potential target of this steroid in these cell lineages (by transactivations) and in the nuclear ER-negative SKBr3 cells (GPR30+) (by proliferation assays). 7β-OH-EpiA exerted anti-estrogenic effects in MCF-7 and MDA-MB-231 cells associated with cell proliferation inhibition and cell cycle arrest. Moreover, transactivation and proliferation with ER agonists assays indicated that 7β-OH-EpiA interacted with ERβ. Data from proliferation assays on the MCF-7, MDA-MB-231 and SKBr3 cell lines suggested that 7β-OH-EpiA may also act through the membrane GPR30 receptor. These results support that this androgenic steroid acts as an anti-estrogenic compound. Moreover, this is the first evidence that low doses of androgenic steroid exert antiproliferative effects in these mammary cancer cells. Further investigations are needed to improve understanding of the observed actions of endogenous 7β-OH-EpiA. Copyright © 2012 Elsevier Inc. All rights reserved.

Athlete exertion injuries.

PubMed

Orava, S; Puranen, J

1978-01-01

Over a period of three years 829 cases of greater than or equal to 16-year-old athlete exertion injuries and syndromes were collected. There were 75 women and 754 men in the series. About 90% of the athletes had been training regularly for more than two years, and 75% of them trained 6 times a week or more. Approximately 52% of the injuries occurred in track and field athletics, about 17% in ball events, 13.6% in skiing, 7.4% in orienteering, and 4.7% in power events. Other sports were associated with fewer exertion injuries. 28.7% of the conditions occurred in the knee, 17% in the ankle, foot and heel, 14.8% in the leg, 8.2% in the back and trunk, 8.1% in the thigh, 7.4% in the achilles tendon. The rest were in the shoulder, neck and upper extremities. In 92% of the patients conservative treatment and rest were used. Only 8% of the cases were treated surgically.

Effects of Dispatcher-assisted Cardiopulmonary Resuscitation on Survival Outcomes in Infants, Children, and Adolescents with Out-of-hospital Cardiac Arrests.

PubMed

Ro, Young Sun; Shin, Sang Do; Song, Kyoung Jun; Hong, Ki Jeong; Ahn, Ki Ok; Kim, Do Kyun; Kwak, Young Ho

2016-11-01

We studied the effect of a dispatcher-assisted cardiopulmonary resuscitation (CPR) program on paediatric out-of-hospital cardiac arrest (OHCA) outcomes by age groups. All emergency medical services (EMS)-treated paediatric OHCAs in Korea were enrolled between 2012 and 2014, excluding cases witnessed by EMS providers and those with unknown outcomes. The cases were divided into three groups: bystander CPR with dispatcher assistance, bystander CPR without dispatcher assistance, and no-bystander CPR. The endpoint was survival until discharge from hospital. Multivariable logistic regression analysis was performed. The final model with an interaction term was evaluated to compare the effects across age groups. A total of 1529 patients (32.8% bystander CPR with dispatcher assistance, 17.3% without dispatcher assistance, and 54.6% no-bystander CPR) were included. Both bystander CPR groups were more likely to have higher rate of survival to discharge (8.8% and 12.1%) compared to no-bystander CPR (3.9%). The adjusted OR (95% CI) for survival to discharge were 1.77 (1.04-3.00) in bystander CPR with dispatcher assistance and 2.86 (1.61-5.08) in without dispatcher assistance compared with no-bystander CPR. By age groups, the adjusted OR (95% CI) in bystander CPR with and without dispatcher assistance were 2.18 (1.07-4.42) and 2.27 (1.01-5.14) for the group aged 9-18 years; 2.32 (0.64-8.44) and 6.21 (1.83-21.01) for the group aged 1-8 years; 1.06 (0.41-2.77) and 2.00 (0.64-6.18) for the group aged 0-12 months, respectively. Bystander CPR, regardless of dispatcher assistance, was associated with improved survival outcomes after OHCA in the paediatric population. However, the associations between dispatcher-assisted bystander CPR and survival outcomes varied by age. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Ways of increasing muscular activity by means of isometric muscular exertion

NASA Technical Reports Server (NTRS)

Kovalik, A. V.

1980-01-01

The effect of isometric muscular exertion on the human body was investigated by having subjects perform basic movements in a sitting position in the conventional manner with additional muscle tension at 50% maximum force and at maximum force. The pulse, arterial pressure, skin temperature, respiratory rate, minute respiratory volume and electrical activity of the muscles involved were all measured. Performance of the exercises with maximum muscular exertion for 20 sec and without movement resulted in the greatest shifts in these indices; in the conventional manner substantial changes did not occur; and with isometric muscular exertion with 50% maximum force with and without movement, optimal functional shifts resulted. The latter is recommended for use in industrial exercises for the prevention of hypodynamia. Ten exercises are suggested.

Perceptions of pesticides exposure risks by operators, workers, residents and bystanders in Greece, Italy and the UK.

PubMed

Remoundou, K; Brennan, M; Sacchettini, G; Panzone, L; Butler-Ellis, M C; Capri, E; Charistou, A; Chaideftou, E; Gerritsen-Ebben, M G; Machera, K; Spanoghe, P; Glass, R; Marchis, A; Doanngoc, K; Hart, A; Frewer, L J

2015-02-01

The EU Directive on the sustainable use of pesticides (EU128/2009/EC) requires European Member States to develop training activities targeting occupational exposure to pesticides, and communication material aimed at residents and bystanders. Risk perceptions, knowledge and attitudes associated with passive and occupational exposure to pesticide potentially influence the extent to which different stakeholders adopt self-protective behaviour. A methodology for assessing the link between attitudes, adoption of self-protective behaviours and exposure was developed and tested. A survey was implemented in the Greece, Italy and the UK, and targeted stakeholders associated with pesticide exposure linked to orchards, greenhouse crops and arable crops respectively. The results indicated that the adoption of protective measures is low for residents and bystanders, with the exception of residents in Greece, when compared to operators and workers, who tend to follow recommended safety practices. A regression analysis was used to examine the factors affecting the probability of adopting protective measures as well the as the level of exposure in the case of operators and workers where data are available. The results indicate that the likelihood of engaging in self-protective behaviour is not significantly affected by perceptions of own health being affected by pesticides for residents and bystanders. However, operators who perceive that their heath has been negatively affected by the use of pesticides are found to be more likely to adopt self-protective behaviours. Gender and country differences, in perceptions, attitudes and self-protection are also observed. Recommendations for improved communication, in particular for vulnerable groups, are provided. Copyright © 2014 Elsevier B.V. All rights reserved.

Dual effects exerted in vitro by micromolar concentrations of deoxynivalenol on undifferentiated caco-2 cells.

PubMed

Manda, Gina; Mocanu, Mihaela Andreea; Marin, Daniela Eliza; Taranu, Ionelia

2015-02-16

Contamination of crops used for food and feed production with Fusarium mycotoxins, such as deoxynivalenol (DON), raise important health and economic issues all along the food chain. Acute exposure to high DON concentrations can alter the intestinal barrier, while chronic exposure to lower doses may exert more subtle effects on signal transduction pathways, leading to disturbances in cellular homeostasis. Using real-time cellular impedance measurements, we studied the effects exerted in vitro by low concentrations of DON (0.37-1.50 μM), relevant for mycotoxin-contaminated food, on the proliferation of undifferentiated Caco-2 cells presenting a tumorigenic phenotype. A 1.5 μM concentration of DON maintained cell adherence of non-proliferating Caco-2 cells, whilst arresting the growth of actively proliferating cells compared with control Caco-2 cells in vitro. At 0.37 μM, DON enhanced Caco-2 cell metabolism, thereby triggering a moderate increase in cell proliferation. The results of the current study suggested that low concentrations of DON commonly detected in food may either limit or sustain the proliferation of colon cancer cells, depending on their proliferation status and on DON concentration. Soluble factors released by Lactobacillus strains can partially counteract the inhibitory action of DON on actively proliferating colon cancer cells. The study also emphasized that real-time cellular impedance measurements were a valuable tool for investigating the dynamics of cellular responses to xenobiotics.

Supraphysiological doses of performance enhancing anabolic-androgenic steroids exert direct toxic effects on neuron-like cells

PubMed Central

Basile, John R.; Binmadi, Nada O.; Zhou, Hua; Yang, Ying-Hua; Paoli, Antonio; Proia, Patrizia

2013-01-01

Anabolic-androgenic steroids (AAS) are lipophilic hormones often taken in excessive quantities by athletes and bodybuilders to enhance performance and increase muscle mass. AAS exert well known toxic effects on specific cell and tissue types and organ systems. The attention that androgen abuse has received lately should be used as an opportunity to educate both athletes and the general population regarding their adverse effects. Among numerous commercially available steroid hormones, very few have been specifically tested for direct neurotoxicity. We evaluated the effects of supraphysiological doses of methandienone and 17-α-methyltestosterone on sympathetic-like neuron cells. Vitality and apoptotic effects were analyzed, and immunofluorescence staining and western blot performed. In this study, we demonstrate that exposure of supraphysiological doses of methandienone and 17-α-methyltestosterone are toxic to the neuron-like differentiated pheochromocytoma cell line PC12, as confirmed by toxicity on neurite networks responding to nerve growth factor and the modulation of the survival and apoptosis-related proteins ERK, caspase-3, poly (ADP-ribose) polymerase and heat-shock protein 90. We observe, in contrast to some previous reports but in accordance with others, expression of the androgen receptor (AR) in neuron-like cells, which when inhibited mitigated the toxic effects of AAS tested, suggesting that the AR could be binding these steroid hormones to induce genomic effects. We also note elevated transcription of neuritin in treated cells, a neurotropic factor likely expressed in an attempt to resist neurotoxicity. Taken together, these results demonstrate that supraphysiological exposure to the AAS methandienone and 17-α-methyltestosterone exert neurotoxic effects by an increase in the activity of the intrinsic apoptotic pathway and alterations in neurite networks. PMID:23675320

Gasdermin D Exerts Anti-inflammatory Effects by Promoting Neutrophil Death.

PubMed

Kambara, Hiroto; Liu, Fei; Zhang, Xiaoyu; Liu, Peng; Bajrami, Besnik; Teng, Yan; Zhao, Li; Zhou, Shiyi; Yu, Hongbo; Zhou, Weidong; Silberstein, Leslie E; Cheng, Tao; Han, Mingzhe; Xu, Yuanfu; Luo, Hongbo R

2018-03-13

Gasdermin D (GSDMD) is considered a proinflammatory factor that mediates pyroptosis in macrophages to protect hosts from intracellular bacteria. Here, we reveal that GSDMD deficiency paradoxically augmented host responses to extracellular Escherichia coli, mainly by delaying neutrophil death, which established GSDMD as a negative regulator of innate immunity. In contrast to its activation in macrophages, in which activated inflammatory caspases cleave GSDMD to produce an N-terminal fragment (GSDMD-cNT) to trigger pyroptosis, GSDMD cleavage and activation in neutrophils was caspase independent. It was mediated by a neutrophil-specific serine protease, neutrophil elastase (ELANE), released from cytoplasmic granules into the cytosol in aging neutrophils. ELANE-mediated GSDMD cleavage was upstream of the caspase cleavage site and produced a fully active ELANE-derived NT fragment (GSDMD-eNT) that induced lytic cell death as efficiently as GSDMD-cNT. Thus, GSDMD is pleiotropic, exerting both pro- and anti-inflammatory effects that make it a potential target for antibacterial and anti-inflammatory therapies. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Genistein, a dietary soy isoflavone, exerts antidepressant-like effects in mice: Involvement of serotonergic system.

PubMed

Hu, Pei; Ma, Li; Wang, Yan-Gui; Ye, Feng; Wang, Chuang; Zhou, Wen-Hua; Zhao, Xin

2017-09-01

Genistein, a principal isoflavone property of soybeans, possesses multiple pharmacological activities such as neuroprotection. Recently, it was reported that genistein exerted antidepressant-like effects in animal models, but the mechanism of action remains ambiguous. The purpose of this study was to investigate the antidepressant-like effect of genistein in mice and explore the underlying mechanism(s), using two mouse models of depression, i.e. forced swim test (FST) and tail suspension test (TST). Chronic, but not acute (single dose), genistein treatment (5, 15 or 45 mg/kg, p.o., once per day for three weeks) exerted dose-dependently antidepressant-like effect in mice, concomitant with escalated levels of brain monoamines and suppressed monoamine oxidase (MAO) activity. Chemical depletion of brain serotonin by PCPA abrogated the antidepressant-like action of genistein, but it was not the case for ablation of NA by DSP-4. Moreover, the anti-depression by genistein was preferentially counteracted by co-administration of 5-HT 1A receptor antagonist WAY-100635, suggesting a pivotal role for 5-HT system coupled with 5-HT 1A receptors in mediating such genistein anti-depression. This point was further validated by the fact that genistein action was potentiated by co-treatment with 8-OH-DPAT, a selective 5-HT 1A receptor agonist. Collectively, these findings confirm that chronic genistein administration to mice engenders antidepressant-like efficacy evidenced by lessened behavioral despair. Serotonergic system that preferentially couples with 5-HT 1A receptors may be critically responsible for the present genistein anti-depression. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rate of Perceived Exertion of Female Aviation Workers Pertaining to Selected Aviation Workspace and Recommended Fitness Regime to Reduce Exertion

NASA Astrophysics Data System (ADS)

Harridon, Mohd

2018-05-01

In aviation maintenance, workers usually work in tight spaces to maintain or repair aircraft. These constricted spaces provide uncomfortable feeling to these workers and in return the workmanship of the workers declined in terms of quality and thus affect the safety of the aircraft. However, some workers are fit enough to go through these conditions without hassle or without much pain. This paper focused upon female aviation workers and collected data on their rate of perceived exertion pertaining to two selected aviation workspaces. The data and analyses showed that those who are fit felt less exertion while those who are not fit felt more exertion. This paper then recommended several physical exercises to increase their fitness and in turn reduce the exertion felt.

Heart rate variability during exertional heat stress: effects of heat production and treatment.

PubMed

Flouris, Andreas D; Bravi, Andrea; Wright-Beatty, Heather E; Green, Geoffrey; Seely, Andrew J; Kenny, Glen P

2014-04-01

We assessed the efficacy of different treatments (i.e., treatment with ice water immersion vs. natural recovery) and the effect of exercise intensities (i.e., low vs. high) for restoring heart rate variability (HRV) indices during recovery from exertional heat stress (EHS). Nine healthy adults (26 ± 3 years, 174.2 ± 3.8 cm, 74.6 ± 4.3 kg, 17.9 ± 2.8 % body fat, 57 ± 2 mL·kg·(-1) min(-1) peak oxygen uptake) completed four EHS sessions incorporating either walking (4.0-4.5 km·h(-1), 2 % incline) or jogging (~7.0 km·h(-1), 2 % incline) on a treadmill in a hot-dry environment (40 °C, 20-30 % relative humidity) while wearing a non-permeable rain poncho for a slow or fast rate of rectal temperature (T re) increase, respectively. Upon reaching a T re of 39.5 °C, participants recovered until T re returned to 38 °C either passively or with whole-body immersion in 2 °C water. A comprehensive panel of 93 HRV measures were computed from the time, frequency, time-frequency, scale-invariant, entropy and non-linear domains. Exertional heat stress significantly affected 60/93 HRV measures analysed. Analyses during recovery demonstrated that there were no significant differences between HRV measures that had been influenced by EHS at the end of passive recovery vs. whole-body cooling treatment (p > 0.05). Nevertheless, the cooling treatment required statistically significantly less time to reduce T re (p < 0.001). While EHS has a marked effect on autonomic nervous system modulation and whole-body immersion in 2 °C water results in faster cooling, there were no observed differences in restoration of autonomic heart rate modulation as measured by HRV indices with whole-body cold-water immersion compared to passive recovery in thermoneutral conditions.

Active Defending and Passive Bystanding Behavior in Bullying: The Role of Personal Characteristics and Perceived Peer Pressure

ERIC Educational Resources Information Center

Pozzoli, Tiziana; Gini, Gianluca

2010-01-01

This study examined the role of pro-victim attitudes, personal responsibility, coping responses to observations of bullying, and perceived peer normative pressure in explaining defending the victim and passive bystanding behavior in bullying. A total of 462 Italian early adolescents (mean age = 13.4 years, SD = 9 months) participated in the study.…

Psychological impact on dispatched local lay rescuers performing bystander cardiopulmonary resuscitation.

PubMed

Zijlstra, Jolande A; Beesems, Stefanie G; De Haan, Rob J; Koster, Rudolph W

2015-07-01

We studied the short-term psychological impact and post-traumatic stress disorder (PTSD)-related symptoms in lay rescuers performing cardiopulmonary resuscitation (CPR) after a text message (TM)-alert for out-of-hospital-cardiac arrest, and assessed which factors contribute to a higher level of PTSD-related symptoms. The lay rescuers received a TM-alert and simultaneously an email with a link to an online questionnaire. We analyzed all questionnaires from February 2013 until October 2014 measuring the short-term psychological impact. We interviewed by telephone all first arriving lay rescuers performing bystander CPR and assessed PTSD-related symptoms with the Impact of Event Scale (IES) 4-6 weeks after the resuscitation. IES-scores 0-8 reflected no stress, 9-25 mild, 26-43 moderate, and 44-75 severe stress. A score ≥ 26 indicated PTSD symptomatology. Of all alerted lay rescuers, 6572 completed the online questionnaire. Of these, 1955 responded to the alert and 507 assisted in the resuscitation. We interviewed 203 first arriving rescuers of whom 189 completed the IES. Of these, 41% perceived no/mild short-term impact, 46% bearable impact and 13% severe impact. On the IES, 81% scored no stress and 19% scored mild stress. None scored moderate or severe stress. Using a multivariable logistic regression model we identified three factors with an independent impact on mild stress level: no automated external defibrillator connected by the lay rescuer, severe short-term impact, and no (very) positive experience. Lay rescuers alerted by text messages, do not show PTSD-related symptoms 4-6 weeks after performing bystander CPR, even if they perceive severe short-term psychological impact. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Exertional Rhabdomyolysis after Spinning.

PubMed

Jeong, Youjin; Kweon, Hyuk-Jung; Oh, Eun-Jung; Ahn, Ah-Leum; Choi, Jae-Kyung; Cho, Dong-Yung

2016-11-01

Any strenuous muscular exercise may trigger rhabdomyolysis. We report an episode of clinically manifested exertional rhabdomyolysis due to stationary cycling, commonly known as spinning. Reports of spinning-related rhabdomyolysis are rare in the English literature, and the current case appears to be the first such case reported in South Korea. A previously healthy 21-year-old Asian woman presented with severe thigh pain and reddish-brown urinary discoloration 24-48 hours after attending a spinning class at a local gymnasium. Paired with key laboratory findings, her symptoms were suggestive of rhabdomyolysis. She required hospital admission to sustain renal function through fluid resuscitation therapy and fluid balance monitoring. Because exertional rhabdomyolysis may occur in any unfit but otherwise healthy individual who indulges in stationary cycling, the potential health risks of this activity must be considered.

Overexpression of GDNF in the uninjured DRG exerts analgesic effects on neuropathic pain following segmental spinal nerve ligation in mice.

PubMed

Takasu, Kumiko; Sakai, Atsushi; Hanawa, Hideki; Shimada, Takashi; Suzuki, Hidenori

2011-11-01

Glial cell line-derived neurotrophic factor (GDNF), a survival-promoting factor for a subset of nociceptive small-diameter neurons, has been shown to exert analgesic effects on neuropathic pain. However, its detailed mechanisms of action are still unknown. In the present study, we investigated the site-specific analgesic effects of GDNF in the neuropathic pain state using lentiviral vector-mediated GDNF overexpression in mice with left fifth lumbar (L5) spinal nerve ligation (SNL) as a neuropathic pain model. A lentiviral vector expressing both GDNF and enhanced green fluorescent protein (EGFP) was constructed and injected into the left dorsal spinal cord, uninjured fourth lumbar (L4) dorsal root ganglion (DRG), injured L5 DRG, or plantar skin of mice. In SNL mice, injection of the GDNF-EGFP-expressing lentivirus into the dorsal spinal cord or uninjured L4 DRG partially but significantly reduced the mechanical allodynia in association with an increase in GDNF protein expression in each virus injection site, whereas injection into the injured L5 DRG or plantar skin had no effects. These results suggest that GDNF exerts its analgesic effects in the neuropathic pain state by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by the uninjured DRG neurons. This article shows that GDNF exerts its analgesic effects on neuropathic pain by acting on the central terminals of uninjured DRG neurons and/or on the spinal cells targeted by these neurons. Therefore, research focusing on these GDNF-dependent neurons in the uninjured DRG would provide a new strategy for treating neuropathic pain. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

The effect of firefighter protective garments, self-contained breathing apparatus and exertion in the heat on postural sway.

PubMed

White, Scott C; Hostler, David

2017-08-01

Fire suppression wearing thermal protective clothing (TPC) and self-contained breathing apparatus (SCBA) challenges a firefighter's balance and may explain firefighter falls. Postural control based on force plate centre of pressure (COP) was compared for healthy subjects wearing TPC and SCBA before and after 20 min of heavy physical exertion in hot conditions. Baseline measures with and without TPC and SCBA (two different SCBA cylinder masses) were compared before and after exertion that included elements of fire suppression activities in an environmental chamber. COP excursion and variability increased with exertion for TPC and SCBA conditions compared to non-stressed conditions. The two different cylinder masses had no significant effect. Wearing TPC and SCBA when physically stressed in a hot environment increases postural sway and exacerbates postural control. Subjects compensated for the extra mass and adjusted to control postural sway with the addition of TPC and SCBA, but the stress protocol amplified these adjustments. Practitioner Summary: Firefighters wear thermal protective clothing (TPC) and self-contained breathing apparatus (SCBA) when heat-stressed and fatigued. Wearing TPC and SCBA was found to negatively impact balance when stressed, but not for non-stressed or two different sized SCBA tanks. Simulating fire-ground conditions wearing TPC and SCBA should be considered for improving balance.

Nurses Need Not Be Guilty Bystanders: Caring for Vulnerable Immigrant Populations

PubMed

Fitzgerald, Elizabeth Moran; Myers, Judith G; Clark, Paul

2016-12-01

Nurses face many dilemmas when providing healthcare to immigrants, a vulnerable population. Racist, rancorous dialogue can create a hostile care environment that may place patients at risk for substandard care. This article presents a two part case study about a Hispanic patient to illustrate both examples of inappropriate dialogue (Part I) and potential nursing actions (Part 2). The authors review myths versus facts about Hispanic immigrants and introduce activist Thomas Merton’s concept of the guilty bystander, the nursing professional code of ethics, and Professor Joseph Badaracco’s concepts of quiet leadership as practical tools and approaches that nurses can use to advocate for safe, quality, ethical care of immigrant populations.

Chronic Exertional Compartment Syndrome

MedlinePlus

... Sometimes chronic exertional compartment syndrome is mistaken for shin splints, a more common cause of leg pain in ... such as running. If you think you have shin splints but they don't get better with self- ...

Exposure of the Bone Marrow Microenvironment to Simulated Solar and Galactic Cosmic Radiation Induces Biological Bystander Effects on Human Hematopoiesis.

PubMed

Almeida-Porada, Graça; Rodman, Christopher; Kuhlman, Bradford; Brudvik, Egil; Moon, John; George, Sunil; Guida, Peter; Sajuthi, Satria P; Langefeld, Carl D; Walker, Stephen J; Wilson, Paul F; Porada, Christopher D

2018-04-26

The stem cell compartment of the hematopoietic system constitutes one of the most radiosensitive tissues of the body and leukemias represent one of the most frequent radiogenic cancers with short latency periods. As such, leukemias may pose a particular threat to astronauts during prolonged space missions. Control of hematopoiesis is tightly governed by a specialized bone marrow (BM) microenvironment/niche. As such, any environmental insult that damages cells of this niche would be expected to produce pronounced effects on the types and functionality of hematopoietic/immune cells generated. We recently reported that direct exposure of human hematopoietic stem cells (HSC) to simulated solar energetic particle (SEP) and galactic cosmic ray (GCR) radiation dramatically altered the differentiative potential of these cells, and that simulated GCR exposures can directly induce DNA damage and mutations within human HSC, which led to leukemic transformation when these cells repopulated murine recipients. In this study, we performed the first in-depth examination to define changes that occur in mesenchymal stem cells present in the human BM niche following exposure to accelerated protons and iron ions and assess the impact these changes have upon human hematopoiesis. Our data provide compelling evidence that simulated SEP/GCR exposures can also contribute to defective hematopoiesis/immunity through so-called "biological bystander effects" by damaging the stromal cells that comprise the human marrow microenvironment, thereby altering their ability to support normal hematopoiesis.

A RETINOIC ACID β2-RECEPTOR AGONIST EXERTS CARDIOPROTECTIVE EFFECTS.

PubMed

Marino, Alice; Sakamoto, Takuya; Tang, Xiao-Han; Gudas, Lorraine J; Levi, Roberto

2018-06-15

We previously discovered that oral treatment with AC261066, a synthetic selective agonist for the retinoic acid β2-receptor (RARβ2), decreases oxidative stress in the liver, pancreas, and kidney of mice fed a high-fat diet (HFD). Since hyperlipidemic states are causally associated with myocardial ischemia and oxidative stress, we have now investigated the effects of AC261066 in an ex-vivo ischemia/reperfusion (I/R) injury model in hearts of two prototypic dysmetabolic mice. We found that a 6-week oral treatment with AC261066 in both genetically hypercholesterolemic (ApoE-/-) and obese (HFD-fed) wild-type mice exerts protective effects when their hearts are subsequently subjected to I/R ex vivo in the absence of added drug. In ApoE-/- mice this cardioprotection ensued without hyperlipidemic changes. Cardioprotection consisted of an attenuation of infarct size, diminution of norepinephrine (NE) spillover, and alleviation of reperfusion arrhythmias. This cardioprotection was associated with a reduction in oxidative stress and mast cell (MC) degranulation. We suggest that the reduction in myocardial injury and adrenergic activation, and the antiarrhythmic effects result from decreased formation of oxygen radicals and toxic aldehydes known to elicit the release of MC-derived renin, promoting the activation of local renin-angiotensin system (RAS) leading to enhanced NE release and reperfusion arrhythmias. Because these beneficial effects of AC261066 occurred at the ex-vivo level following oral drug treatment, our data suggest that AC261066 could be viewed as a therapeutic means to reduce I/R injury of the heart, and potentially also considered in the treatment of other cardiovascular ailments such as chronic arrhythmias, and cardiac failure. The American Society for Pharmacology and Experimental Therapeutics.

A tale of two cities: The role of neighborhood socioeconomic status in spatial clustering of bystander CPR in Austin and Houston☆

PubMed Central

Root, Elisabeth Dowling; Gonzales, Louis; Persse, David E.; Hinchey, Paul R.; McNally, Bryan; Sasson, Comilla

2013-01-01

Background Despite evidence to suggest significant spatial variation in out-of-hospital cardiac arrest (OHCA) and bystander cardiopulmonary resuscitation (BCPR) rates, geographic information systems (GIS) and spatial analysis have not been widely used to understand the reasons behind this variation. This study employs spatial statistics to identify the location and extent of clusters of bystander CPR in Houston and Travis County, TX. Methods Data were extracted from the Cardiac Arrest Registry to Enhance Survival for two U.S. sites –Austin-Travis County EMS and the Houston Fire Department – between October 1, 2006 and December 31, 2009. Hierarchical logistic regression models were used to assess the relationship between income and racial/ethnic composition of a neighborhood and BCPR for OHCA and to adjust expected counts of BCPR for spatial cluster analysis. The spatial scan statistic was used to find the geographic extent of clusters of high and low BCPR. Results Results indicate spatial clusters of lower than expected BCPR rates in Houston. Compared to BCPR rates in the rest of the community, there was a circular area of 4.2 km radius where BCPR rates were lower than expected (RR = 0.62; p < 0.0001 and RR = 0.55; p = 0.037) which persist when adjusted for individual-level patient characteristics (RR = 0.34; p = 0.027) and neighborhood-level race (RR = 0.34; p = 0.034) and household income (RR = 0.34; p = 0.046). We also find a spatial cluster of higher than expected BCPR in Austin. Compared to the rest of the community, there was a 23.8 km radius area where BCPR rates were higher than expected (RR = 1.75; p = 0.07) which disappears after controlling for individual-level characteristics. Conclusions A geographically targeted CPR training strategy which is tailored to individual and neighborhood population characteristics may be effective in reducing existing disparities in the provision of bystander CPR for out-of-hospital cardiac arrest. PMID:23318916

Amplexicaule A exerts anti-tumor effects by inducing apoptosis in human breast cancer

PubMed Central

Shu, Guangwen; Wan, Dingrong; He, Feng; Loaec, Morgann; Ding, Yali; Li, Jun; Dovat, Sinisa; Yang, Gaungzhong; Song, Chunhua

2016-01-01

Chemotherapy is the main treatment for patients with breast cancer metastases, but natural alternatives have been receiving attention for their potential as novel anti-tumor reagents. Amplexicaule A (APA) is a flavonoid glucoside isolated from rhizomes of Polygonum amplexicaule D. Don var. sinense Forb (PADF). We found that APA has anti-tumor effects in a breast cancer xenograft mouse model and induces apoptosis in breast cancer cell lines. APA increased levels of cleaved caspase-3,-8,-9 and PARP, which resulted from suppression of MCL-1 and BCL-2 expression in the cells. APA also inactivated the Akt/mTOR pathway in breast cancer cells. Thus, APA exerts a strong anti-tumor effect on breast cancer cells, most likely through induction of apoptosis. Our study is the first to identify this novel anti-tumor compound and provides a new strategy for isolation and separation of single compounds from herbs. PMID:26943775

Extracts from Lentinula edodes (Shiitake) Edible Mushrooms Enriched with Vitamin D Exert an Anti-Inflammatory Hepatoprotective Effect.

PubMed

Drori, Ariel; Shabat, Yehudit; Ben Ya'acov, Ami; Danay, Ofer; Levanon, Dan; Zolotarov, Lidya; Ilan, Yaron

2016-04-01

Vitamin D has been known for its anti-inflammatory properties. Extracts derived from Lentinula edodes (Shiitake) edible mushroom exert an anti-inflammatory effect. These extracts contain high levels of ergosterol, which converts into ergocalciferol (vitamin D2) following exposure to ultraviolet light, followed by absorption and hydroxylation into the active form 25-hydroxyvitamin D [25(OH)D]. To determine the anti-inflammatory effect of overexpression of vitamin D in edible mushrooms, L. edodes mushrooms were exposed to ultraviolet-B light, freeze-dried, followed by measurement of vitamin D2 contents, in their dry weight. C57B1/6 mice were orally treated with vitamin D2-enriched or nonenriched mushroom extract prior and during concanavalin A-immune-mediated liver injury. Exposure to ultraviolet light increased vitamin D2 content in Shiitake edible mushrooms. Following feeding of vitamin D-enriched mushroom extracts to mice with immune-mediated hepatitis, a significant decrease in liver damage was noted. This was shown by a decrease in alanine aminotransferase and aspartate aminotransferase serum levels, a decrease in proportion of mice with severe liver injury, and by improvement in liver histology. These effects were associated with a decrease in serum interferon gamma levels. A synergistic effect was noted between the anti-inflammatory effect of the mushroom extracts and that of vitamin D. Oral administration of vitamin D-enriched L. edodes edible mushroom exerts a synergistic anti-inflammatory effect in the immune-mediated hepatitis. The data support its potential use as safe immunomodulatory adjuvant for the treatment of HCV and nonalcoholic steatohepatitis.

Perceived Exertion of the PACER in High School Students

ERIC Educational Resources Information Center

Smith, John D.; Holmes, Patricia A.

2013-01-01

The purpose of this study was to explore high school students' perceived exertion after participating in the Progressive Aerobic Cardiovascular Endurance Run (PACER). Immediately after completing the PACER, students (N = 792) indicated their perceived exertion on the OMNI rating of perceived exertion (RPE) for children (1-10 scale). All students,…

Exertional Rhabdomyolysis after Spinning

PubMed Central

Jeong, Youjin; Oh, Eun-Jung; Ahn, Ah-Leum; Choi, Jae-Kyung; Cho, Dong-Yung

2016-01-01

Any strenuous muscular exercise may trigger rhabdomyolysis. We report an episode of clinically manifested exertional rhabdomyolysis due to stationary cycling, commonly known as spinning. Reports of spinning-related rhabdomyolysis are rare in the English literature, and the current case appears to be the first such case reported in South Korea. A previously healthy 21-year-old Asian woman presented with severe thigh pain and reddish-brown urinary discoloration 24–48 hours after attending a spinning class at a local gymnasium. Paired with key laboratory findings, her symptoms were suggestive of rhabdomyolysis. She required hospital admission to sustain renal function through fluid resuscitation therapy and fluid balance monitoring. Because exertional rhabdomyolysis may occur in any unfit but otherwise healthy individual who indulges in stationary cycling, the potential health risks of this activity must be considered. PMID:27900075

Azoxystrobin, a mitochondrial complex III Qo site inhibitor, exerts beneficial metabolic effects in vivo and in vitro.

PubMed

Gao, An-Hui; Fu, Yan-Yun; Zhang, Kun-Zhi; Zhang, Mei; Jiang, Hao-Wen; Fan, Li-Xia; Nan, Fa-Jun; Yuan, Chong-Gang; Li, Jia; Zhou, Yu-Bo; Li, Jing-Ya

2014-07-01

Several anti-diabetes drugs exert beneficial effects against metabolic syndrome by inhibiting mitochondrial function. Although much progress has been made toward understanding the role of mitochondrial function inhibitors in treating metabolic diseases, the potential effects of these inhibitors on mitochondrial respiratory chain complex III remain unclear. We investigated the metabolic effects of azoxystrobin (AZOX), a Qo inhibitor of complex III, in a high-fat diet-fed mouse model with insulin resistance in order to elucidate the mechanism by which AZOX improves glucose and lipid metabolism at the metabolic cellular level. Acute administration of AZOX in mice increased the respiratory exchange ratio. Chronic treatment with AZOX reduced body weight and significantly improved glucose tolerance and insulin sensitivity in high-fat diet-fed mice. AZOX treatment resulted in decreased triacylglycerol accumulation and down-regulated the expression of genes involved in liver lipogenesis. AZOX increased glucose uptake in L6 myotubes and 3T3-L1 adipocytes and inhibited de novo lipogenesis in HepG2 cells. The findings indicate that AZOX-mediated alterations to lipid and glucose metabolism may depend on AMP-activated protein kinase (AMPK) signaling. AZOX, a Qo inhibitor of mitochondrial respiratory complex III, exerts whole-body beneficial effects on the regulation of glucose and lipid homeostasis in high-fat diet-fed mice. These findings provide evidence that a Qo inhibitor of mitochondrial respiratory complex III could represent a novel approach for the treatment of obesity. Copyright © 2014 Elsevier B.V. All rights reserved.

You Are What You Read: The Belief Systems of Cyber-Bystanders on Social Networking Sites.

PubMed

Leung, Angel N M; Wong, Natalie; Farver, JoAnn M

2018-01-01

The present study tested how exposure to two types of responses to a hypothetical simulated Facebook setting influenced cyber-bystanders' perceived control and normative beliefs using a 4 cyberbully-victim group (pure cyberbullies, non-involved, pure cyberbullied victims, and cyberbullied-victims) × 2 condition (offend vs. defend) experimental design. 203 Hong Kong Chinese secondary school and university students (132 females, 71 males; 12 to 28; M = 16.70; SD = 3.03 years old) were randomly assigned into one of two conditions. Results showed that participants' involvement in cyberbullying significantly related to their control beliefs about bully and victim assisting behaviors, while exposure to the two different conditions (offend vs. defend comments) was related to both their control and normative beliefs. In general, the defend condition promoted higher control beliefs to help the victims and promoted higher normative beliefs to help the victims. Regardless of their past involvement in cyberbullying and exposure to offend vs. defend conditions, both cyber-bullies and cyber-victims were more inclined to demonstrate normative beliefs to help victims than to assist bullies. These results have implications for examining environmental influences in predicting bystander behaviors in cyberbullying contexts, and for creating a positive environment to motivate adolescents to become "upstanders" in educational programs to combat cyberbullying.

Fisetin exerts antihyperalgesic effect in a mouse model of neuropathic pain: engagement of spinal serotonergic system

PubMed Central

Zhao, Xin; Wang, Chuang; Cui, Wu-Geng; Ma, Qing; Zhou, Wen-Hua

2015-01-01

Fisetin, a natural flavonoid, has been shown in our previous studies to exert antidepressant-like effect. As antidepressant drugs are clinically used to treat chronic neuropathic pain, this work aimed to investigate the potential antinociceptive efficacies of fisetin against neuropathic pain and explore mechanism(s). We subjected mice to chronic constriction injury (CCI) by loosely ligating the sciatic nerves, and Hargreaves test or von Frey test was used to assess thermal hyperalgesia or mechanical allodynia, respectively. Chronic fisetin treatment (5, 15 or 45 mg/kg, p.o.) ameliorated thermal hyperalgesia (but not mechanical allodynia) in CCI mice, concomitant with escalated levels of spinal monoamines and suppressed monoamine oxidase (MAO)-A activity. The antihyperalgesic action of fisetin was abolished by chemical depletion of spinal serotonin (5-HT) but potentiated by co-treatment with 5-HTP, a precursor of 5-HT. Moreover, intraperitoneal (i.p.) or intrathecal (i.t.) co-treatment with 5-HT7 receptor antagonist SB-258719 completely abrogated fisetin's antihyperalgesia. These findings confirm that chronic fisetin treatment exerts antinociceptive effect on thermal hyperalgesia in neuropathic mice, with spinal serotonergic system (coupled with 5-HT7) being critically involved. Of special benefit, fisetin attenuated co-morbidly behavioral symptoms of depression and anxiety (evaluated in forced swim test, novelty suppressed feeding test and light-dark test) evoked by neuropathic pain. PMID:25761874

How Students' Perceptions of the School Climate Influence Their Choice to Upstand, Bystand, or Join Perpetrators of Bullying

ERIC Educational Resources Information Center

Ferráns, Silvia Diazgranados; Selman, Robert L.

2014-01-01

The authors of this article, Silvia Diazgranados Ferráns and Robert Selman, use an emergent framework to explore how the rules of the school culture at different perceived school climates affect early adolescents' decisions to upstand, bystand, or join the perpetrators when they witness peer aggression and bullying. Through a grounded theory…

They Know I Saw It: Evaluation Apprehension and Diffusion of Responsibility in Bystander Reactions to a Violent Crime.

ERIC Educational Resources Information Center

Gottlieb, Avi; Schwartz, Shalom H.

Male and female bystanders witnessed a violent theft in the course of a bogus "ESP Experiment." In addition to the subjects' sex, two experimental manipulations were orthogonally crossed. The subject was either the only one to witness the emergency, or witnessed it with an additional participant (diffusion of responsibility), and the subject's…

Post-exertion neurocognitive test failure among student-athletes following concussion.

PubMed

McGrath, Neal; Dinn, Wayne M; Collins, Michael W; Lovell, Mark R; Elbin, R J; Kontos, Anthony P

2013-01-01

The purpose of the present study was to examine post-exertion (PE) neurocognitive performance among student-athletes following concussion who were asymptomatic and returned to baseline normal neurocognitive test levels at rest. This study examined the neurocognitive performance of a sub-set of student-athletes who 'failed' to perform at baseline levels of neurocognitive function, i.e. exhibited downward reliable change index (RCI) alterations following a moderate exertional protocol during recovery from concussion. A retrospective records review was carried out of Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) and neuropsychological consultation data among athletes with sports-related concussion from a network of 22 schools and one junior hockey programme. Fifty-four student-athletes met inclusion criteria and participated in the study. A total of 27.7% of concussed student-athletes who were symptom-free and returned to baseline on ImPACT at rest (i.e. no longer demonstrated performance deficits on neurocognitive tests) exhibited cognitive decline following moderate physical exertion. The PE cognitive changes were not simply general performance effects, but significant changes in memory ability in the presence of intact processing speed functions. The PE-Pass and PE-Fail groups did not, however, differ on post-concussive symptoms or concussion history. Clinicians' return-to-play evaluation protocols should include post-exertional computerized neurocognitive testing.

Time-based partitioning model for predicting neurologically favorable outcome among adults with witnessed bystander out-of-hospital CPA.

PubMed

Abe, Toshikazu; Tokuda, Yasuharu; Cook, E Francis

2011-01-01

Optimal acceptable time intervals from collapse to bystander cardiopulmonary resuscitation (CPR) for neurologically favorable outcome among adults with witnessed out-of-hospital cardiopulmonary arrest (CPA) have been unclear. Our aim was to assess the optimal acceptable thresholds of the time intervals of CPR for neurologically favorable outcome and survival using a recursive partitioning model. From January 1, 2005 through December 31, 2009, we conducted a prospective population-based observational study across Japan involving consecutive out-of-hospital CPA patients (N = 69,648) who received a witnessed bystander CPR. Of 69,648 patients, 34,605 were assigned to the derivation data set and 35,043 to the validation data set. Time factors associated with better outcomes: the better outcomes were survival and neurologically favorable outcome at one month, defined as category one (good cerebral performance) or two (moderate cerebral disability) of the cerebral performance categories. Based on the recursive partitioning model from the derivation dataset (n = 34,605) to predict the neurologically favorable outcome at one month, 5 min threshold was the acceptable time interval from collapse to CPR initiation; 11 min from collapse to ambulance arrival; 18 min from collapse to return of spontaneous circulation (ROSC); and 19 min from collapse to hospital arrival. Among the validation dataset (n = 35,043), 209/2,292 (9.1%) in all patients with the acceptable time intervals and 1,388/2,706 (52.1%) in the subgroup with the acceptable time intervals and pre-hospital ROSC showed neurologically favorable outcome. Initiation of CPR should be within 5 min for obtaining neurologically favorable outcome among adults with witnessed out-of-hospital CPA. Patients with the acceptable time intervals of bystander CPR and pre-hospital ROSC within 18 min could have 50% chance of neurologically favorable outcome.

Testosterone replacement therapy and the heart: friend, foe or bystander?

PubMed Central

Canfield, Steven; Wang, Run

2016-01-01

The role of testosterone therapy (TTh) in cardiovascular disease (CVD) outcomes is still controversial, and it seems will remain inconclusive for the moment. An extensive body of literature has investigated the association of endogenous testosterone and use of TTh with CVD events including several meta-analyses. In some instances, a number of studies reported beneficial effects of TTh on CVD events and in other instances the body of literature reported detrimental effects or no effects at all. Yet, no review article has scrutinized this body of literature using the magnitude of associations and statistical significance reported from this relationship. We critically reviewed the previous and emerging body of literature that investigated the association of endogenous testosterone and use of TTh with CVD events (only fatal and nonfatal). These studies were divided into three groups, “beneficial (friendly use)”, “detrimental (foe)” and “no effects at all (bystander)”, based on their magnitude of associations and statistical significance from original research studies and meta-analyses of epidemiological studies and of randomized controlled trials (RCT’s). In this review article, the studies reporting a significant association of high levels of testosterone with a reduced risk of CVD events in original prospective studies and meta-analyses of cross-sectional and prospective studies seems to be more consistent. However, the number of meta-analyses of RCT’s does not provide a clear picture after we divided it into the beneficial, detrimental or no effects all groups using their magnitudes of association and statistical significance. From this review, we suggest that we need a study or number of studies that have the adequate power, epidemiological, and clinical data to provide a definitive conclusion on whether the effect of TTh on the natural history of CVD is real or not. PMID:28078222

Testosterone replacement therapy and the heart: friend, foe or bystander?

PubMed

Lopez, David S; Canfield, Steven; Wang, Run

2016-12-01

The role of testosterone therapy (TTh) in cardiovascular disease (CVD) outcomes is still controversial, and it seems will remain inconclusive for the moment. An extensive body of literature has investigated the association of endogenous testosterone and use of TTh with CVD events including several meta-analyses. In some instances, a number of studies reported beneficial effects of TTh on CVD events and in other instances the body of literature reported detrimental effects or no effects at all. Yet, no review article has scrutinized this body of literature using the magnitude of associations and statistical significance reported from this relationship. We critically reviewed the previous and emerging body of literature that investigated the association of endogenous testosterone and use of TTh with CVD events (only fatal and nonfatal). These studies were divided into three groups, "beneficial (friendly use)", "detrimental (foe)" and "no effects at all (bystander)", based on their magnitude of associations and statistical significance from original research studies and meta-analyses of epidemiological studies and of randomized controlled trials (RCT's). In this review article, the studies reporting a significant association of high levels of testosterone with a reduced risk of CVD events in original prospective studies and meta-analyses of cross-sectional and prospective studies seems to be more consistent. However, the number of meta-analyses of RCT's does not provide a clear picture after we divided it into the beneficial, detrimental or no effects all groups using their magnitudes of association and statistical significance. From this review, we suggest that we need a study or number of studies that have the adequate power, epidemiological, and clinical data to provide a definitive conclusion on whether the effect of TTh on the natural history of CVD is real or not.

Do 'mind over muscle' strategies work? Examining the effects of attentional association and dissociation on exertional, affective and physiological responses to exercise.

PubMed

Lind, Erik; Welch, Amy S; Ekkekakis, Panteleimon

2009-01-01

Despite the well established physical and psychological benefits derived from leading a physically active life, rates of sedentary behaviour remain high. Dropout and non-compliance are major contributors to the problem of physical inactivity. Perceptions of exertion, affective responses (e.g. displeasure or discomfort), and physiological stress could make the exercise experience aversive, particularly for beginners. Shifting one's attentional focus towards environmental stimuli (dissociation) instead of one's body (association) has been theorized to enhance psychological responses and attenuate physiological stress. Research evidence on the effectiveness of attentional focus strategies, however, has been perplexing, covering the entire gamut of possible outcomes (association and dissociation having been shown to be both effective and ineffective). This article examines the effects of manipulations of attentional focus on exertional and affective responses, as well as on exercise economy and tolerance. The possible roles of the characteristics of the exercise stimulus (intensity, duration) and the exercise participants, methodological issues, and limitations of experimental designs are discussed. In particular, the critical role of exercise intensity is emphasized. Dissociative strategies may be more effective in reducing perceptions of exertion and enhancing affective responses at low to moderate exercise intensities, but their effectiveness may be diminished at higher and near-maximal levels, at which physiological cues dominate. Conversely, associative strategies could enable the exerciser to regulate intensity to avoid injury or overexertion. Thus, depending on intensity, both strategies have a place in the 'toolbox' of the public health or exercise practitioner as methods of enhancing the exercise experience and promoting long-term compliance.

Chronic administration of parecoxib exerts anxiolytic-like and memory enhancing effects and modulates synaptophysin expression in mice.

PubMed

Wang, Bo; Jin, Xin; Kuang, Xin; Tian, Shaowen

2017-11-13

Previous studies have shown that cyclooxygenase-2, a key enzyme that converts arachidonic acid to prostaglandins, is involved in anxiety and cognitive processes, but few studies have investigated the effects of chronic administration of cyclooxygenase-2 inhibitors on anxiety, learning and memory under normal physiological conditions. The aim of the study was to investigate the effects of chronic administration of parecoxib, a cyclooxygenase-2 inhibitor, on anxiety behavior and memory performance under normal physiological conditions and to explore the possible neural mechanism underlying parecoxib-mediated effects. Adult male ICR mice were randomly divided into four groups: the control group and three parecoxib groups. Mice received normal saline or parecoxib (2.5, 5.0 or 10 mg/kg) intraperitoneal injection once a day for 21 days, respectively. Elevated plus-maze, novel object recognition and Y maze tests were conducted on day 23, 24 and 26, respectively. Four additional groups that received same drug treatment were used to measure synaptophysin protein levels by western blot and prostaglandin E2 (PGE2) levels by ELISA in the amygdala and hippocampus on day 26. Chronic parecoxib exerted an anxiolytic-like effect in the plus-maze test test, and enhanced memory performance in the novel object recognition and Y maze tests. Western blot analysis showed that chronic parecoxib down-regulated synaptophysin levels in the amygdala and up-regulated synaptophysin levels in the hippocampus. ELISA assay showed that chronic parecoxib inhibited PGE2 in the hippocampus but not amygdala. Chronic parecoxib exerts anxiolytic-like and memory enhancing effects, which might be mediated through differential modulation of synaptophysin and PGE2 in the amygdala and hippocampus.

Influence of the bystander phenomenon on the chromosome aberration pattern in human lymphocytes induced by in vitro alpha-particle exposure.

PubMed

Schmid, Ernst; Roos, H

2009-04-01

A recent publication on both chromosome-type and chromatid-type aberrations in lymphocytes of patients during treatment with radium-224 for ankylosing spondilitis has revived the question of whether the chromatid-type aberrations may be the consequence of factors released by irradiated cells. Therefore, the aim of the present study was to investigate the influence of such a bystander phenomenon on the chromosome aberration pattern of lymphocytes. Monolayers of human lymphocytes were irradiated with 1 Gy of alpha-particles from an americium-241 source in the absence or presence of whole blood, autologous plasma or culture medium. In the presence of any liquid covering the monolayer during irradiation, the chromatid-type aberrations were, contrary to expectation, elevated. Whereas the intercellular distribution of dicentrics was significantly overdispersed, the chromatid-type aberrations showed a regular dispersion. It can be concluded that the enhanced frequency of chromatid aberrations is the result of a damage signal or a bystander phenomenon released by irradiated cells.

20 CFR 220.135 - Exertional and nonexertional limitations.

Code of Federal Regulations, 2011 CFR

2011-04-01

... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...

20 CFR 220.135 - Exertional and nonexertional limitations.

Code of Federal Regulations, 2013 CFR

2013-04-01

... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...

20 CFR 220.135 - Exertional and nonexertional limitations.

Code of Federal Regulations, 2012 CFR

2012-04-01

... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...

20 CFR 220.135 - Exertional and nonexertional limitations.

Code of Federal Regulations, 2014 CFR

2014-04-01

... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...

The neural basis of the bystander effect--the influence of group size on neural activity when witnessing an emergency.

PubMed

Hortensius, Ruud; de Gelder, Beatrice

2014-06-01

Naturalistic observation and experimental studies in humans and other primates show that observing an individual in need automatically triggers helping behavior. The aim of the present study is to clarify the neurofunctional basis of social influences on individual helping behavior. We investigate whether when participants witness an emergency, while performing an unrelated color-naming task in an fMRI scanner, the number of bystanders present at the emergency influences neural activity in regions related to action preparation. The results show a decrease in activity with the increase in group size in the left pre- and postcentral gyri and left medial frontal gyrus. In contrast, regions related to visual perception and attention show an increase in activity. These results demonstrate the neural mechanisms of social influence on automatic action preparation that is at the core of helping behavior when witnessing an emergency. Copyright © 2014 Elsevier Inc. All rights reserved.

Phloretin exerts hypoglycemic effect in streptozotocin-induced diabetic rats and improves insulin resistance in vitro.

PubMed

Shen, Xin; Zhou, Nan; Mi, Le; Hu, Zishuo; Wang, Libin; Liu, Xueying; Zhang, Shengyong

2017-01-01

The present study investigated the possible antiobesity and hypoglycemic effects of phloretin (Ph). In an attempt to discover the hypoglycemic effect and potential mechanism of Ph, we used the streptozotocin-induced diabetic rats and (L6) myotubes. Daily oral treatment with Ph for 4 weeks significantly ( P <0.05) reduced postprandial blood glucose and improved islet injury and lipid metabolism. Glucose consumption and glucose tolerance were improved by Ph via GOD-POD method. Western blot results revealed that the expression of Akt, PI3K, IRS-1, and GLUT4 were upregulated in skeletal muscle of type 2 diabetes (T2D) rats and in L6 myotubes by Ph. The immunofluorescence studies confirmed that Ph improved the translocation of GLUT4 in L6 myotubes. Ph exerted hypoglycemic effects in vivo and in vitro, hence it may play an important role in the management of diabetes.

Phloretin exerts hypoglycemic effect in streptozotocin-induced diabetic rats and improves insulin resistance in vitro

PubMed Central

Shen, Xin; Zhou, Nan; Mi, Le; Hu, Zishuo; Wang, Libin; Liu, Xueying; Zhang, Shengyong

2017-01-01

The present study investigated the possible antiobesity and hypoglycemic effects of phloretin (Ph). In an attempt to discover the hypoglycemic effect and potential mechanism of Ph, we used the streptozotocin-induced diabetic rats and (L6) myotubes. Daily oral treatment with Ph for 4 weeks significantly (P<0.05) reduced postprandial blood glucose and improved islet injury and lipid metabolism. Glucose consumption and glucose tolerance were improved by Ph via GOD–POD method. Western blot results revealed that the expression of Akt, PI3K, IRS-1, and GLUT4 were upregulated in skeletal muscle of type 2 diabetes (T2D) rats and in L6 myotubes by Ph. The immunofluorescence studies confirmed that Ph improved the translocation of GLUT4 in L6 myotubes. Ph exerted hypoglycemic effects in vivo and in vitro, hence it may play an important role in the management of diabetes. PMID:28223777

Active Citizens, Good Citizens, and Insouciant Bystanders: The Educational Implications of Chinese University Students' Civic Participation via Social Networking

ERIC Educational Resources Information Center

Ke, Lin; Starkey, Hugh

2014-01-01

This virtual ethnographic study explores how Chinese university students use social network sites (SNSs) to participate in civic activities. An ideal of "active" citizens is contrasted with good citizens (Crick) and insouciant bystanders. We find that students engage with the civic issues embedded in everyday life; their online civic…

Exertional myopathy in whooping cranes (Grus americana) with prognostic guidelines.

PubMed

Hanley, Christopher S; Thomas, Nancy J; Paul-Murphy, Joanne; Hartup, Barry K

2005-09-01

Exertional myopathy developed in three whooping cranes (Grus americana) secondary to routine capture, handling, and trauma. Presumptive diagnosis of exertional myopathy was based on history of recent capture or trauma, clinical signs, and elevation of aspartate aminotransferase, alanine aminotransferase, creatine kinase, lactate dehydrogenase, and serum potassium. Treatments were attempted in each case, but ultimately were not successful. Gross and microscopic lesions at necropsy confirmed the diagnosis in each case, with the leg musculature most severely affected. Guidelines for determining prognosis of exertional myopathy in cranes have been included based on the analysis of these cases and others in the literature. As treatment is largely unrewarding, prevention remains the key in controlling exertional myopathy. Identification of predisposing factors and proper handling, immobilization, and transportation techniques can help prevent development of exertional myopathy in cranes.

Exertional myopathy in whooping cranes (Grus americana) with prognostic guidlelines

USGS Publications Warehouse

Hanley, C.S.; Thomas, N.J.; Paul-Murphy, P.; Hartup, B.K.

2005-01-01

Exertional myopathy developed in three whooping cranes (Grus americana) secondary to routine capture, handling, and trauma. Presumptive diagnosis of exertional myopathy was based on history of recent capture or trauma, clinical signs, and elevation of aspartate aminotransferase, alanine aminotransferase, creatine kinase, lactate dehydrogenase, and serum potassium. Treatments were attempted in each case, but ultimately were not successful. Gross and microscopic lesions at necropsy confirmed the diagnosis in each case, with the leg musculature most severely affected. Guidelines for determining prognosis of exertional myopathy in cranes have been included based on the analysis of these cases and others in the literature. As treatment is largely unrewarding, prevention remains the key in controlling exertional myopathy. Identification of predisposing factors and proper handling, immobilization, and transportation techniques can help prevent development of exertional myopathy in cranes.

Bystander signaling in C. elegans: proton microbeam studies

PubMed Central

Nelson, Gregory; Jones, Tamako; Ortloff, Leticia; Ford, John; Nuñez, Delia; Braby, Leslie

2014-01-01

Biological model: In this project, we investigated the control of radiation-induced genotoxic damage expression in somatic cells of the nematode Caenorhabditis elegans. We measured genotoxic damage in the C. elegans intestine by irradiating young larvae with 20 intestinal cells. Fourteen of these cells undergo exactly one nuclear division without cytoplasmic division leading to 14 binucleate cells. This nuclear division is synchronized and occurs at the first larval molt. Irradiation induces chromosome aberrations including dicentrics which we can quantify as stable anaphase bridges in the binucleate cells of young adult intestines. The endpoint is dose- and LET-dependent and we have demonstrated that individual intestinal cells have unique radiosensitivities. Results: The project has two components, a genetic screen for genes that control cell sensitivity and a microbeam component to directly probe individual cells. The genetic screen has identified several genes in NHEJ repair and telomere metabolism that modulate overall bridge frequency. Knockout mutants of cku-70, cku-80 and lig-4 greatly sensitize animals for anaphase bridge induction. A statistical method was used to determine whether induction of bridges was strictly random and cell autonomous and we determined that expression of bridges in pairs of cells was, in fact, non-random which suggested that signaling between cells affected the pattern of bridge expression. This allowed us to conduct an RNAi and mutation screen for genes that control the signaling (block non-random distributions) and several candidates have been identified. To directly test the notion that signaling of genotoxic damage occurs, we conducted experiments with alpha particles collimated through slits in metal foils and showed that genotoxic damage could be expressed many cell diameters away from a partial body exposure site. Thus, an in vivo bystander effect was demonstrated. Dose targeting was then improved to small regional exposures

Sasa health exerts a protective effect on Her2/NeuN mammary tumorigenesis.

PubMed

Ren, Mingqiang; Reilly, R Todd; Sacchi, Nicoletta

2004-01-01

Bamboo grass leaves of different Sasa species have been widely used in food and medicine in Eastern Asia for hundreds of years. Of special interest are Kumazasa (Sasa senanensis rehder) leaves used to prepare an alkaline extract known as Sasa Health. This extract was reported to inhibit both the development and growth of mammary tumors in a mammary tumor strain of virgin SHN mice (1). We found that Sasa Health exerts a significant protective effect on spontaneous mammary tumorigenesis in another mouse model of human breast cancer, the transgenic FVB-Her2/NeuN mouse model. Two cohorts of Her2/NeuN female mice of different age (eleven-week-old and twenty-four-week-old) chronically treated with Sasa Health in drinking water showed both a delay in the development of tumors and reduced tumor multiplicity. Sasa Health also induced inhibition of mammary duct branching and side bud development in association with reduced angiogenesis. Altogether these findings indicate that Sasa Health contains phytochemicals that can effectively retard spontaneous mammary tumorigenesis.

The prozone effect exerted by the complement-binding anti-Lea on anti-D.

PubMed

Joshi, Sanmukh R; Parekh, Kamlesh H

2017-01-01

Prozone phenomenon is seen with very high-titer antibodies in an immune serum. The prozone effect on anti-D by a low-titer anti-Le a was investigated associated with neonatal jaundice. Standard methods were used in investigations. The child was born at full-term developed mild jaundice. With weak direct antiglobulin test+, her indirect serum bilirubin was progressed to 27.5 mg/dL in 48 h. Anti-D and anti-Le a were detected in the mother. Both these antibodies were detected in the child's serum though the eluate from red blood cells (RBCs) contained only anti-D. Mother's anti-D was masked by anti-Le a if the RBCs possessed both the antigens together. Anti-D was revealed only with D-positive RBCs lacking Le a or if the serum was modified by mixing with Le a+ saliva or was heated at 56°C or fortified with citrate solution. An anti-D showed prozone effect exerted by the complement-fixing anti-Le a in the test.

Noble or Malevolent in a Moment of Dismay: How Postsecondary Students Construe and Characterize Bystander Action in School Violence Shooting Incidents

ERIC Educational Resources Information Center

Underhill, Dyan Whitlow

2012-01-01

Multiple incidents of postsecondary school shooting violence have occurred in American society--prompting concern about safety on college campuses, administrators' roles in prevention, and proactive and responsible bystander actions. Active shooter plans have become more established in educational environments, with efforts are directed…

Adenosine and inosine exert cytoprotective effects in an in vitro model of liver ischemia-reperfusion injury

PubMed Central

MÓDIS, KATALIN; GERŐ, DOMOKOS; STANGL, RITA; ROSERO, OLIVÉR; SZIJÁRTÓ, ATTILA; LOTZ, GÁBOR; MOHÁCSIK, PETRA; SZOLECZKY, PETRA; COLETTA, CIRO; SZABÓ, CSABA

2013-01-01

Liver ischemia represents a common clinical problem. In the present study, using an in vitro model of hepatic ischemia-reperfusion injury, we evaluated the potential cytoprotective effect of the purine metabolites, such as adenosine and inosine, and studied the mode of their pharmacological actions. The human hepatocellular carcinoma-derived cell line HepG2 was subjected to combined oxygen-glucose deprivation (COGD; 0-14-24 h), followed by re-oxygenation (0-4-24 h). Adenosine or inosine (300–1,000 μM) were applied in pretreatment. Cell viability and cytotoxicity were measured by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide and lactate dehydrogenase methods, respectively. The results showed that both adenosine and inosine exerted cytoprotective effects, and these effects were not related to receptor-mediated actions, since they were not prevented by selective adenosine receptor antagonists. On the other hand, the adenosine deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl) adenine hydrochloride (EHNA, 10 μM) markedly and almost fully reversed the protective effect of adenosine during COGD, while it did not influence the cytoprotective effect of inosine in the same assay conditions. These results suggest that the cytoprotective effects are related to intracellular actions, and, in the case of adenosine also involve intracellular conversion to inosine. The likely interpretation of these findings is that inosine serves as an alternative source of energy to produce ATP during hypoxic conditions. The protective effects are also partially dependent on adenosine kinase, as the inhibitor 4-amino-5-(3-bromophenyl)-7-(6-morpholino-pyridin-3-yl)pyrido[2,3-d]pyrimidine, 2HCl (ABT 702, 30 μM) significantly reversed the protective effect of both adenosine and inosine during hypoxia and re-oxygenation. Collectively, the current results support the view that during hypoxia, adenosine and inosine exert cytoprotective effects via receptor

Adenosine and inosine exert cytoprotective effects in an in vitro model of liver ischemia-reperfusion injury.

PubMed

Módis, Katalin; Gerő, Domokos; Stangl, Rita; Rosero, Olivér; Szijártó, Attila; Lotz, Gábor; Mohácsik, Petra; Szoleczky, Petra; Coletta, Ciro; Szabó, Csaba

2013-02-01

Liver ischemia represents a common clinical problem. In the present study, using an in vitro model of hepatic ischemia-reperfusion injury, we evaluated the potential cytoprotective effect of the purine metabolites, such as adenosine and inosine, and studied the mode of their pharmacological actions. The human hepatocellular carcinoma-derived cell line HepG2 was subjected to combined oxygen-glucose deprivation (COGD; 0-14-24 h), followed by re-oxygenation (0-4-24 h). Adenosine or inosine (300-1,000 µM) were applied in pretreatment. Cell viability and cytotoxicity were measured by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide and lactate dehydrogenase methods, respectively. The results showed that both adenosine and inosine exerted cytoprotective effects, and these effects were not related to receptor-mediated actions, since they were not prevented by selective adenosine receptor antagonists. On the other hand, the adenosine deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl) adenine hydrochloride (EHNA, 10 µM) markedly and almost fully reversed the protective effect of adenosine during COGD, while it did not influence the cytoprotective effect of inosine in the same assay conditions. These results suggest that the cytoprotective effects are related to intracellular actions, and, in the case of adenosine also involve intracellular conversion to inosine. The likely interpretation of these findings is that inosine serves as an alternative source of energy to produce ATP during hypoxic conditions. The protective effects are also partially dependent on adenosine kinase, as the inhibitor 4-amino-5-(3-bromophenyl)-7-(6‑morpholino-pyridin-3-yl)pyrido[2,3-d]pyrimidine, 2HCl (ABT 702, 30 µM) significantly reversed the protective effect of both adenosine and inosine during hypoxia and re-oxygenation. Collectively, the current results support the view that during hypoxia, adenosine and inosine exert cytoprotective effects via receptor

Using Ratings of Perceived Exertion in Physical Education

ERIC Educational Resources Information Center

Lagally, Kristen M.

2013-01-01

Ratings of perceived exertion have been shown to be a valid method of monitoring physical activity intensity for both adults and children. As such, this subjective method may serve as an alternative to objective measurements for assessing students' performance on national standards 2 and 4. The OMNI-Child perceived exertion scales were…

Force Exertion Capacity Measurements in Haptic Virtual Environments

ERIC Educational Resources Information Center

Munih, Marko; Bardorfer, Ales; Ceru, Bojan; Bajd, Tadej; Zupan, Anton

2010-01-01

An objective test for evaluating functional status of the upper limbs (ULs) in patients with muscular distrophy (MD) is presented. The method allows for quantitative assessment of the UL functional state with an emphasis on force exertion capacity. The experimental measurement setup and the methodology for the assessment of maximal exertable force…

Berberine exerts antioxidant effects via protection of spiral ganglion cells against cytomegalovirus-induced apoptosis.

PubMed

Zhuang, Wei; Li, Ting; Wang, Caiji; Shi, Xi; Li, Yalan; Zhang, Shili; Zhao, Zeqi; Dong, Hongyan; Qiao, Yuehua

2018-06-01

Cytomegalovirus (CMV) is the leading cause of sensorineural hearing loss (SNHL) in children because of its damage to the cochlea and spiral ganglion cells. Therefore, it has become a top priority to devise new methods to effectively protect spiral ganglion cells from damage. Berberine (BBR) has gained attention for its vast beneficial biological effects through immunomodulation, and its anti-inflammatory and anti-apoptosis properties. However, the effect of BBR on spiral ganglion cells and molecular mechanisms are still unclear. This study aims to investigate whether BBR has an anti-apoptosis effect in CMV-induced apoptosis in cultured spiral ganglion cells and explore the possible mechanism. In this study, TUNEL and MTT assays significantly demonstrated that low doses of BBR did not promote cell apoptosis and they also inhibited the CMV-induced cultured spiral ganglion cell apoptosis. Immunofluorescence and Western blot assays indicated that the anti-apoptosis effect of BBR was related to Nox3. Mitochondrial calcium and Western blot assays revealed that NMDAR1 mediated this anti-apoptosis effect. Our results demonstrated that BBR exerted an anti-apoptosis effect against CMV in cultured spiral ganglion cells, and the mechanism is related to NMDAR1/Nox3-mediated mitochondrial reactive oxygen species (ROS) generation. Copyright © 2018 Elsevier Inc. All rights reserved.

Minocycline fails to exert antiepileptogenic effects in a rat status epilepticus model.

PubMed

Russmann, Vera; Goc, Joanna; Boes, Katharina; Ongerth, Tanja; Salvamoser, Josephine D; Siegl, Claudia; Potschka, Heidrun

2016-01-15

The tetracycline antibiotic minocycline can exert strong anti-inflammatory, antioxidant, and antiapoptotic effects. There is cumulating evidence that epileptogenic brain insults trigger neuroinflammation and anti-inflammatory concepts can modulate the process of epileptogenesis. Based on the mechanisms of action discussed for minocycline, the compound is of interest for intervention studies as it can prevent the polarization of microglia into a pro-inflammatory state. Here, we assessed the efficacy of sub-chronic minocycline administration initiated immediately following an electrically-induced status epilepticus in rats. The treatment did not affect the development of spontaneous seizures. However, minocycline attenuated behavioral long-term consequences of status epilepticus with a reduction in hyperactivity and hyperlocomotion. Furthermore, the compound limited the spatial learning deficits observed in the post-status epilepticus model. The typical status epilepticus-induced neuronal cell loss was evident in the hippocampus and the piriform cortex. Minocycline exposure selectively protected neurons in the piriform cortex and the hilus, but not in the hippocampal pyramidal layer. In conclusion, the data argue against an antiepileptogenic effect of minocycline in adult rats. However, the findings suggest a disease-modifying impact of the tetracycline affecting the development of behavioral co-morbidities, as well as long-term consequences on spatial learning. In addition, minocycline administration resulted in a selective neuroprotective effect. Although strong anti-inflammatory effects have been proposed for minocycline, we could not verify these effects in our experimental model. Considering the multitude of mechanisms claimed to contribute to minocycline's effects, it is of interest to further explore the exact mechanisms underlying the beneficial effects in future studies. Copyright © 2015 Elsevier B.V. All rights reserved.

The Effects of Direction of Exertion, Path, and Load Placement in Nursing Cart Pushing and Pulling Tasks: An Electromyographical Study.

PubMed

Kao, Huei Chu; Lin, Chiuhsiang Joe; Lee, Yung Hui; Chen, Su Huang

2015-01-01

The purpose of this study was to explore the effects of direction of exertion (DOE) (pushing, pulling), path (walking in a straight line, turning left, walking uphill), and load placement (LP) (the 18 blocks were indicated by X, Y and Z axis; there were 3 levels on the X axis, 2 levels on the Y axis, and 3 levels on the Z axis) on muscle activity and ratings of perceived exertion in nursing cart pushing and pulling tasks. Ten participants who were female students and not experienced nurses were recruited to participate in the experiment. Each participant performed 108 experimental trials in the study, consisting of 2 directions of exertion (push and pull), 3 paths, and 18 load placements (indicated by X, Y and Z axes). A 23kg load was placed into one load placement. The dependent variables were electromyographic (EMG) data of four muscles collected bilaterally as follows: Left (L) and right (R) trapezius (TR), flexor digitorum superficialis (FDS), extensor digitorum (ED), and erector spinae (ES) and subjective ratings of perceived exertion (RPE). Split-split-plot ANOVA was conducted to analyze significant differences between DOE, path, and LP in the EMG and RPE data. Pulling cart tasks produced a significantly higher activation of the muscles (RTR:54.4%, LTR:50.3%, LFDS:57.0%, LED:63.4%, RES:40.7%, LES:36.7%) than pushing cart tasks (RTR:42.4%, LTR:35.1%, LFDS:32.3%, LED:55.1%, RES:33.3%, LES:32.1%). A significantly greater perceived exertion was found in pulling cart tasks than pushing cart tasks. Significantly higher activation of all muscles and perceived exertion were observed for walking uphill than walking in a straight line and turning left. Significantly lower muscle activity of all muscles and subject ratings were observed for the central position on the X axis, the bottom position on the Y axis, and the posterior position on the Z axis. These findings suggest that nursing staff should adopt forward pushing when moving a nursing cart, instead of backward

The Effects of Direction of Exertion, Path, and Load Placement in Nursing Cart Pushing and Pulling Tasks: An Electromyographical Study

PubMed Central

Kao, Huei Chu; Lin, Chiuhsiang Joe; Lee, Yung Hui; Chen, Su Huang

2015-01-01

The purpose of this study was to explore the effects of direction of exertion (DOE) (pushing, pulling), path (walking in a straight line, turning left, walking uphill), and load placement (LP) (the 18 blocks were indicated by X, Y and Z axis; there were 3 levels on the X axis, 2 levels on the Y axis, and 3 levels on the Z axis) on muscle activity and ratings of perceived exertion in nursing cart pushing and pulling tasks. Ten participants who were female students and not experienced nurses were recruited to participate in the experiment. Each participant performed 108 experimental trials in the study, consisting of 2 directions of exertion (push and pull), 3 paths, and 18 load placements (indicated by X, Y and Z axes). A 23kg load was placed into one load placement. The dependent variables were electromyographic (EMG) data of four muscles collected bilaterally as follows: Left (L) and right (R) trapezius (TR), flexor digitorum superficialis (FDS), extensor digitorum (ED), and erector spinae (ES) and subjective ratings of perceived exertion (RPE). Split-split-plot ANOVA was conducted to analyze significant differences between DOE, path, and LP in the EMG and RPE data. Pulling cart tasks produced a significantly higher activation of the muscles (RTR:54.4%, LTR:50.3%, LFDS:57.0%, LED:63.4%, RES:40.7%, LES:36.7%) than pushing cart tasks (RTR:42.4%, LTR:35.1%, LFDS:32.3%, LED:55.1%, RES:33.3%, LES:32.1%). A significantly greater perceived exertion was found in pulling cart tasks than pushing cart tasks. Significantly higher activation of all muscles and perceived exertion were observed for walking uphill than walking in a straight line and turning left. Significantly lower muscle activity of all muscles and subject ratings were observed for the central position on the X axis, the bottom position on the Y axis, and the posterior position on the Z axis. These findings suggest that nursing staff should adopt forward pushing when moving a nursing cart, instead of backward

Caffeine ingestion, affect and perceived exertion during prolonged cycling.

PubMed

Backhouse, Susan H; Biddle, Stuart J H; Bishop, Nicolette C; Williams, Clyde

2011-08-01

Caffeine's metabolic and performance effects have been widely reported. However, caffeine's effects on affective states during prolonged exercise are unknown. Therefore, this was examined in the present study. Following an overnight fast and in a randomised, double-blind, counterbalanced design, twelve endurance trained male cyclists performed 90 min of exercise at 70% VO(₂ max) 1h after ingesting 6 mg kg⁻¹ BM of caffeine (CAF) or placebo (PLA). Dimensions of affect and perceived exertion were assessed at regular intervals. During exercise, pleasure ratings were better maintained (F(₃,₃₈)=4.99, P < 0.05) in the CAF trial compared to the PLA trial with significantly higher ratings at 15, 30 and 75 min (all P < 0.05). Perceived exertion increased (F(₃,₃₈) = 19.86, P < 0.01) throughout exercise and values, overall, were significantly lower (F(₁,₁₁) = 9.26, P < 0.05) in the CAF trial compared to the PLA trial. Perceived arousal was elevated during exercise but did not differ between trials. Overall, the results suggest that a moderate dose of CAF ingested 1h prior to exercise maintains a more positive subjective experience during prolonged cycling. This observation may partially explain caffeine's ergogenic effects. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Role of Individual Correlates and Class Norms in Defending and Passive Bystanding Behavior in Bullying: A Multilevel Analysis

ERIC Educational Resources Information Center

Pozzoli, Tiziana; Gini, Gianluca; Vieno, Alessio

2012-01-01

This study investigates possible individual and class correlates of defending and passive bystanding behavior in bullying, in a sample of 1,825 Italian primary school (mean age = 10 years 1 month) and middle school (mean age = 13 years 2 months) students. The findings of a series of multilevel regression models show that both individual (e.g.,…

Should I Say Something? Dating and Sexual Aggression Bystander Intervention among High School Youth. National Issue Brief Number 92

ERIC Educational Resources Information Center

Edwards, Katie M.; Eckstein, Robert P.; Rodenhizer-Stämpfli , Kara Anne

2015-01-01

Using data from a sample of 218 high school youth from three high schools in New England (one rural, two urban), this brief discusses dating and sexual aggression bystander intervention among high school youth. Authors Katie Edwards, Robert Eckstein, and Kara Anne Rodenhizer-Stämpfli report that an overwhelming majority (93.6 percent) of high…

THE EFFECTS OF DIFFERENT TRUNK INCLINATIONS ON BILATERAL TRUNK MUSCULAR ACTIVITIES, CENTRE OF PRESSURE AND FORCE EXERTIONS IN STATIC PUSHING POSTURES.

PubMed

Sanjaya, Kadek Heri; Lee, Soomin; Sriwarno, Andar Bagus; Shimomura, Yoshihito; Katsuura, Tetsuo

2014-06-01

In order to reconcile contradictory results from previous studies on manual pushing, a study was conducted to examine the effect of trunk inclination on muscular activities, centre of pressure (COP) and force exertion during static pushing. Ten subjects pushed at 0 degrees, 15 degrees, 30 degrees, and 45 degrees body inclinations in parallel and staggered feet stances. Wall and ground force plates measured pushing force, wall COP, vertical ground reaction force (GRF) and ground COP. Electromyogram data were recorded at 10 trunk muscle sites. Pushing force was found to increase with body inclination. GRF peaked at 15 degrees and reached its lowest level at the 45 degrees inclination. The lowest wall force plate standard deviation of COP displacement was found at the 30 degrees inclination. The lowest low back muscular activity was found at the 15 degrees and 30 degrees inclinations. Based on force exertion, muscular load, and stability, the 30 degrees body inclination was found to be the best posture for static pushing. This study also showed asymmetry in muscular activity and force exertion which has been received less attention in manual pushing studies. These findings will require further study.

The effects of flipped learning for bystander cardiopulmonary resuscitation on undergraduate medical students.

PubMed

Nakanishi, Taizo; Goto, Tadahiro; Kobuchi, Taketsune; Kimura, Tetsuya; Hayashi, Hiroyuki; Tokuda, Yasuharu

2017-12-22

To compare bystander cardiopulmonary resuscitation skills retention between conventional learning and flipped learning for first-year medical students. A post-test only control group design. A total of 108 participants were randomly assigned to either the conventional learning or flipped learning. The primary outcome measures of time to the first chest compression and the number of total chest compressions during a 2-minute test period 6 month after the training were assessed with the Mann-Whitney U test. Fifty participants (92.6%) in the conventional learning group and 45 participants (83.3%) in the flipped learning group completed the study. There were no statistically significant differences 6 months after the training in the time to the first chest compression of 33.0 seconds (interquartile range, 24.0-42.0) for the conventional learning group and 31.0 seconds (interquartile range, 25.0-41.0) for the flipped learning group (U=1171.0, p=0.73) or in the number of total chest compressions of 101.5 (interquartile range, 90.8-124.0) for the conventional learning group and 104.0 (interquartile range, 91.0-121.0) for the flipped learning group (U=1083.0, p=0.75). The 95% confidence interval of the difference between means of the number of total chest compressions 6 months after the training did not exceed a clinically important difference defined a priori. There were no significant differences between the conventional learning group and the flipped learning group in our main outcomes. Flipped learning might be comparable to conventional learning, and seems a promising approach which requires fewer resources and enables student-centered learning without compromising the acquisition of CPR skills.

Tipepidine, a non-narcotic antitussive, exerts an antidepressant-like effect in the forced swimming test in adrenocorticotropic hormone-treated rats.

PubMed

Kawaura, Kazuaki; Ogata, Yukino; Honda, Sokichi; Soeda, Fumio; Shirasaki, Tetsuya; Takahama, Kazuo

2016-04-01

We investigated whether tipepidine exerts an antidepressant-like effect in the forced swimming test in adrenocorticotropic hormone (ACTH)-treated rats, which is known as a treatment-resistant depression model, and we studied the pharmacological mechanisms of the effects of tipepidine. Male Wistar rats (5-7 weeks old) were used in this study. Tipepidine (20 and 40 mg/kg, i.p.) decreased the immobility time in the forced swimming test in ACTH-treated rats. The anti-immobility effect of tipepidine was blocked by a catecholamine-depleting agent, alpha-methyl-p-tyrosine (300 mg/kg, s.c.), but not by a serotonin-depleting agent, p-chlorophenylalanine. The anti-immobility effect of tipepidine was also blocked by a dopamine D1 receptor antagonist, SCH23390 (0.02 mg/kg, s.c.) and an adrenaline α2 receptor antagonist, yohimbine (2 mg/kg, i.p.). In microdialysis technique, tipepidine (40 mg/kg, i.p.) increased the extracellular dopamine level of the nucleus accumbens (NAc) in ACTH-treated rats. These results suggest that tipepidine exerts an antidepressant-like effect in the forced swimming test in ACTH-treated rats, and that the effect of tipepidine is mediated by the stimulation of dopamine D1 receptors and adrenaline α2 receptors. The results also suggest that an increase in the extracellular dopamine level in the NAc may be involved in the antidepressant-like effect of tipepidine in ACTH-treated rats. Copyright © 2016. Published by Elsevier B.V.

Syringaldehyde exerts neuroprotective effect on cerebral ischemia injury in rats through anti-oxidative and anti-apoptotic properties