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BACKGROUND There is an urgent need for preclinical models of prostate cancer; however, clinically relevant patient-derived prostate cancer xenografts (PDXs) are demanding to establish. METHODS Sixty-seven patients who were undergoing palliative transurethral surgery or radical prostatectomy for histologically confirmed, clinically relevant prostate cancer were included in the study. Fresh prostate cancer tissue was identified by frozen analysis in 48 patients. The cancer tissue was transplanted subcutaneously and under the renal capsule of NSG and NOG mice supplemented with human testosterone. All growing PDXs were evaluated by histology and immunohistochemistry. RESULTS Early assessment of the animals at least three months after transplantation included 27/48 (56.3%) eligible PDX cohorts. PDX growth was detected in 10/27 (37%) mouse cohorts. Eight of the ten PDXs were identified as human donor derived lymphomas, including seven Epstein Barr virus (EBV)-positive diffuse large B-cell lymphomas and one EBV-negative peripheral T-cell lymphoma. One sample consisted of benign prostatic tissue, and one sample comprised a benign epithelial cyst. Prostate cancer was not detected in any of the samples. CONCLUSIONS Tumors that arise within the first three months after prostate cancer xenografting may represent patient-derived EBV-positive lymphomas in up to 80% of the early growing PDXs when using triple knockout NSG immunocompromised mice. Therefore, lymphoma should be excluded in prostate cancer xenografts that do not resemble typical prostatic adenocarcinoma. Prostate 9999: XX-XX, 2014. © 2015 Wiley Periodicals, Inc.

The present studies examined whether implicit or explicit autonomy dispositions moderate the relationship between felt autonomy and well-being. Study 1 (N = 187 undergraduate students) presents an initial test of the moderator hypothesis by predicting flow experience from the interaction of autonomy need satisfaction and autonomy dispositions. Study 2 (N = 127 physically inactive persons) used vignettes involving an autonomy (un)supportive coach to test a moderated mediation model in which perceived coach autonomy support leads to well-being through basic need satisfaction. Again, the effects of need satisfaction on well-being were hypothesized to be moderated by an implicit autonomy disposition. Study 1 showed that individuals with a strong implicit autonomy (but not power or achievement) motive disposition derived more flow experience from felt autonomy than individuals with a weak implicit autonomy disposition. Study 2 revealed that perceived autonomy support from sports coaches, which we experimentally induced with a vignette method, leads to autonomy satisfaction, leading in turn to positive effects on well-being. This indirect effect held at high and average but not low implicit autonomy disposition. The results indicate that the degree to which people benefit from autonomy need satisfaction depends on their implicit disposition toward autonomy.

In the present research, we conducted two studies designed to examine the joint influence of avoidance temperament and avoidance-based achievement goals on the experience of flow on a creativity task. In both a laboratory study (N = 101; Mage = 22.61, SDage = 4.03; 74.3% female) and a naturalistic study (N = 102; Mage = 16.23, SDage = 1.13; 48% female), participants high in avoidance temperament were shown to experience greater flow when performance-avoidance goals were induced; no differences were found in any of the other three achievement goal conditions from the 2 × 2 achievement goal framework. These findings reveal a short-term benefit for a disposition-goal match grounded in avoidance motivation, and point to the need for more research on both avoidance-based matches and the short-term versus long-term implications of such matches.

The present research investigates whether and how learned symbols for failure reduce task performance. We tested the effect of number priming in two countries with different learning histories for numbers. Priming numbers associated with failure (6 in Germany and 1 in Switzerland) were hypothesized to reduce performance. As expected, in Switzerland, priming with the failure number 1 reduced performance (Study 1), whereas in Germany, priming with the failure number 6 impaired performance in analogy tasks (Study 2). Study 2 additionally analyzed the mechanism and showed that the relationship between failure number priming and performance was mediated by evoked avoidance motivation and that dispositional fear of failure moderated this mediation.

Background: Previous research has focused on the positive consequences of flow, an intrinsically rewarding state of deep absorption. In contrast, the present research links flow to impaired risk awareness and to risky behaviour. We expected flow to enhance self-efficacy beliefs, which in turn were hypothesised to result in low risk awareness and risky behaviour in sports. In addition, we predicted that individuals' level of experience in the activity would moderate the expected effects. Methods: One study with kayakers (Study 1) and two studies with rock climbers (Studies 2 and 3) were conducted. Kayakers completed a survey while still on the river; climbers responded during and upon completion of a climb. Results: In all studies flow was related to risk awareness. Study 2 additionally showed its association with risky behaviour. Studies 2 and 3 revealed that these relationships were mediated by self-efficacy. The mediations were moderated by level of experience (Study 3). Conclusions: The results indicated that inexperienced but not experienced participants respond to self-efficacy beliefs evoked by flow with impaired risk awareness and with risky behaviour. Theoretical implications for flow and risk research as well as practical implications for risk prevention are discussed.

We have integrated the basic psychological needs approach from self-determination theory with motive disposition theory in order to enhance the prediction of flow experience in sports. We hypothesize that an environment that enables people to fulfill their basic psychological needs for competence and social relatedness results in flow. Additionally, we assume that the effect of competence need satisfaction is moderated by the achievement motive and that the effect of need-for-relatedness satisfaction is moderated by the affiliation motive. Four studies show the expected positive effects of need satisfaction on flow and further confirm that high achievement and affiliation-motivated individuals benefit more from competence and relatedness sports environments, respectively, than individuals low in these motives.

Objective Research on the strength model of self-regulation is burgeoning, but little empirical work has focused on the link between distinct types of daily goal pursuit and the depletion of self-regulatory resources. The authors conducted two studies on the link between avoidance goals and resource depletion. Method Study 1 (283 [228 female] Caucasians, ages 18–51) investigated the concurrent and longitudinal relations between avoidance goals and resource depletion over a 1-month period. Study 2 (132 [93 female] Caucasians, ages 18–49) investigated the concurrent and longitudinal relations between avoidance goals and resource depletion over a 1-month period and explored resource depletion as a mediator of the avoidance goal to subjective well-being relation. Results Studies 1 and 2 documented both a concurrent and a longitudinal negative relationship between avoidance goals and self-regulatory resources, and Study 2 additionally showed that self-regulatory resources mediate the negative link between avoidance goals and subjective well-being. Ancillary analyses demonstrated that the results observed in the two studies were independent of neuroticism. Conclusions These findings advance knowledge in both the resource depletion and avoidance goal literatures, and bolster the view that avoidance goal pursuit over time represents a self-regulatory vulnerability.

Receptor-targeted therapies have become standard in the treatment of various lymphomas. In view of its unparalleled specificity for the malignant B-cell clone, the B-cell receptor (BCR) on B cell lymphoma cells is a potential therapeutic target. We have used two BCR epitope mimicking peptides binding to the Burkitt's lymphoma cell lines CA46 and SUP-B8. We proved their functionality by demonstrating calcium flux and BCR-mediated endocytosis upon peptide receptor binding. Toxicity experiments in vitro via cross-linking of the BCR with tetramerized epitope mimics lead to apoptosis in both cell lines but was far more effective in SUP-B8 cells. We established a SUP-B8-based disseminated Burkitt's lymphoma model in NOD/SCID mice. Treatment of tumor-bearing mice with tetramerized epitope mimics had significant anti-tumor effects in vivo. We conclude that peptide-mediated, BCR-targeted therapy is a promising approach which may be explored and further developed for application in highly aggressive lymphoma.

Taking the affiliation motive as an example, present research examines whether the negative effects of implicit–explicit motive incongruence on health is moderated by emotional disclosure. Starting from the point of view that motive incongruence works as a chronic stressor and therefore causes impairment of health, we predicted that participants who use the stress-reducing coping strategy of emotional disclosure should be less affected by the negative effects of motive incongruence on health than participants who do not use this stress-coping strategy. Two studies confirmed this hypothesis. Participants with affiliation motive incongruence who practiced emotional disclosure used less medication (Study 1, n = 85) and reported lower somatization symptoms (Study 2, n = 102) than motive incongruent individuals who did not disclose their emotions to others. Copyright © 2008 John Wiley & Sons, Ltd.