This study examined the bystander effect in cyberbullying. Using self-reported data from 257 Czech respondents who had witnessed a cyberbullying attack, we tested whether provided help decreased with increased number of other bystanders. We controlled for several individual and contextual factors, including empathy, social self-efficacy, empathic response to victimization, and relationship to t...

Bystander effects induced by low dose of ionizing radiation have been shown to widely exist in many cell types and may have a significant impact on radiation risk assessment. Though many studies have been reported on this phenomenological observation, the mechanisms underlying this process are not clear, especially on the questions of how soon after irradiation the bystander effects can be init...

Radiation therapy is a primary treatment modality for brain tumors, yet it has been linked to the increased incidence of secondary, post-radiation therapy cancers. These cancers are thought to be linked to indirect radiation-induced bystander effect. Bystander effect occurs when irradiated cells communicate damage to nearby, non-irradiated 'bystander' cells, ultimately contributing to genome de...

Introduction Radiation-induced bystander effect (RIBE) is a phenomenon in which radiation signals are transmitted from irradiated cells to non-irradiated ones, inducing radiation effects in these cells. RIBE plays an effective role in radiation response at environmentally relevant low doses and in radiotherapy, given its impact on adjacent normal tissues or those far from the irradiated tumor. ...

Introduction: Transient receptor potential vanilloid type 1 (TRPV1) and protein kinase Cγ (PKCγ) are involved in sensitization/desensitization to noxious stimuli. We aimed to examine the gene expression levels of TRPV1 and PKCγ in rat lumbosacral cord and midbrain on days 1, 4 and 8 of induction of morphine analgesic tolerance. Methods: Two groups of male Wistar rats received ...

Clinical trials of adenoviral p53 gene therapy provide the evidence that the bystander effect induced by the wild-type p53 gene transfer on adjacent tumor cells contributes to tumor progression; its mechanism, however, remains uncharacterized. We report in this work that injection of adenovirus expressing the human wild-type p53 gene (Ad5CMVp53) into established human colorectal tumors in nu/nu...

Histone H2AX undergoes phosphorylation at Ser-139 (gamma-H2AX) rapidly in response to DNA double-strand breaks (DSBs) induced by ionizing radiation. The post-translational modification of H2AX plays a central role in responses to radiation, including the repair of DSBs. Although ataxia telangiectasia mutated (ATM) kinase phosphorylates Ser-139 of H2AX in vitro, the post-translational modificati...

BACKGROUND In response to DNA double-strand breaks (DSBs), eukaryotic cells rapidly phosphorylate histone H2A isoform H2AX at a C-terminal serine (to form gamma-H2AX) and accumulate repair proteins at or near DSBs. To date, these events have been defined primarily at the resolution of light microscopes, and the relationship between gamma-H2AX formation and repair protein recruitment remains to ...

LPS induces dendritic cell (DC) activation, but the precise in vivo mechanism is unclear since DCs express low levels of TLR4. Here, it is shown that DCs can be activated in response to LPS through a bystander mechanism. This result was obtained using chimeric mice reconstituted with LPS-responsive and nonresponsive bone marrow cells. Thus, after indirect in vivo conditioning by LPS, bystander-...

OBJECTIVE Radiation effects induced in non-irradiated cells are termed radiation-induced bystander effects (RIBE). The present study intends to examine the RIBE response of QU-DB bystander cells to first, second and third radiation fractions and compare their cumulative outcome with an equal, single acute dose. MATERIALS AND METHODS This experimental study irradiated three groups of target ce...