Effects of Approach and Avoid Mindsets on Performance, Self-regulatory Cognition, and Affect in a Multi-task Environment

Despite numerous studies of approach- and avoidant mindsets, relatively little research has addressed the impact of such motivational orientations on performance and emotion in a real-time, multi-task setting. A laboratory simulation is reported that examines the influence of an induced approach-centered, an avoidance-centered, and a “neutral” motivational mindset upon multiple aspects of task performance, self-regulatory cognition, and affect. Undergraduate females randomly assigned to one of three mindset conditions performed a simulated automobile drive across one practice and two experimental trials. Dependent measures included divided attention, behavioral indicators of driving “cautiousness” in relatively safe straight roadway sections as well as during more risk-filled driving, multiple aspects of self-regulatory thinking (including self-monitoring, intended effort, and self-administered consequences), and positive and negative affect. Results revealed that the avoidant mindset produced poorer executive attention (i.e., fewer correctly detected divided attention events), more “cautious” driving behavior and reduced performance variability (i.e., greater control) when driving on presumably safe, straight roadway sections, lower self-reports of intended effort, and greater negative affect relative to the approach mindset. Results are intepreted within a self-regulation-centered motivational framework. Implications of the multi-task simulation for the study of normal and disordered adjustment are considered.     

Growth inhibition of estrogen independent MXT mouse mammary carcinomas in mice treated with an agonist or antagonist of LH-RH,an analog of somatostatin,or a combination

Summary Female BDF₁ mice inoculated with MXT (3.2) estrogen independent mouse mammary carcinoma were treated for three weeks with microcapsules of the luteinizing hormone-releasing hormone (LH-RH) agonist [D-Trp⁶]LH-RH, the antagonist SB-75, the somatostatin analog RC-160, or combinations. The lack of estrogen dependence of the tumor was proved by bilateral surgical ovariectomy, which had no effect. In two experiments, treatment with 25µg/day doses of each analog alone resulted in a significant inhibition of tumor growth as shown by a 40–53% inhibition of tumor volumes, 38–43% decrease in tumor weights, and histological signs of tumor regression. However, the combination of SB-75 or [D-Trp⁶]LH-RH with somatostatin analog RC-160 caused greater reduction of tumor volume (68 and 61%) or tumor weights (59 and 56%), than single analogs, and histologically the occurrence of apoptosis and decrease in AgNOR numbers was more pronounced in the groups receiving combination therapy. Specific binding sites for [D-Trp⁶]LH-RH, EGF, and IGF-I were demonstrated in the tumor membranes. The binding capacity of LH-RH receptors was decreased by treatment with the analogs, the greatest down-regulation being caused by combination therapy. A significant decrease in EGF binding capacity was observed after treatment with the LH-RH analogs, alone or especially in combination with somatostatin analog RC-160. The combination of these analogs also caused a reduction in IGF-I receptors. The finding that LH-RH agonists and antagonists and somatostatin analogs inhibit the growth of estrogen independent mammary tumors, and that combinations are more effective than single analogs, might be of practical importance in human breast cancer therapy.     

Relating cell and tissue mechanics: Implications and applications

The Differential Adhesion Hypothesis (DAH) posits that differences in adhesion provide the driving force for morphogenetic processes. A manifestation of differential adhesion is tissue liquidity and a measure for it is tissue surface tension. In terms of this property, DAH correctly predicts global developmental tissue patterns. However, it provides little information on how these patterns arise from the movement and shape changes of cells. We provide strong qualitative and quantitative support for tissue liquidity both in true developmental context and in vitro assays. We follow the movement and characteristic shape changes of individual cells in the course of specific tissue rearrangements leading to liquid-like configurations. Finally, we relate the measurable tissue-liquid properties to molecular entities, whose direct determination under realistic three-dimensional culture conditions is not possible. Our findings confirm the usefulness of tissue liquidity and provide the scientific underpinning for a novel tissue engineering technology. Developmental Dynamics 237:2438-2449, 2008. (c) 2008 Wiley-Liss, Inc.     

Inhibitory effect of antagonists of bombesin and growth hormone-releasing hormone on orthotopic and intraosseous growth and invasiveness of PC-3 human prostate cancer in nude mice.

PURPOSE: To determine whether antagonists of growth hormone-releasing hormone (GHRH) and bombesin/gastrin-releasing peptide (BN/GRP) can inhibit the orthotopic and metastatic growth of PC-3 human androgen-independent prostate cancers. EXPERIMENTAL DESIGN: The effects of administration of GHRH antagonist MZ-J-7-118, BN/GRP antagonist RC-3940-II, and their combination on the growth and metastatic spread of PC-3 tumors implanted orthotopically into nude mice were evaluated. The efficacy of this treatment on PC-3 tumors implanted intratibially and s.c. was also determined. RESULTS: Treatment with MZ-J-7-118, RC-3940-II, or their combination significantly inhibited the growth of PC-3 tumors implanted orthotopically, intraosseously, and s.c. The combination of the two antagonists had the greatest effect, inhibiting orthotopic tumor growth by 77%, intratibially implanted tumors by 86%, and s.c. tumors by 86%. The therapy with BN/GRP and GHRH antagonists, especially in combination, also reduced the local tumor spread and distant metastases in animals bearing orthotopic tumors. Combination therapy was likewise the most effective in reducing the incidence and severity of tibial osteolytic lesions and pathologic fractures in intraosseously implanted tumors. High-affinity binding sites for BN/GRP and GHRH were found in s.c. and orthotopic PC-3 tumor samples. MZ-J-7-118, RC-3940-II, and the combination of both compounds inhibited in vitro growth of PC-3 cells. CONCLUSIONS: Our findings show the efficacy of BN/GRP antagonists and GHRH antagonists for the treatment of advanced prostate cancer in preclinical metastatic models. As BN/GRP antagonists are already in clinical trials and GHRH antagonists are effective in androgen-independent prostate cancer models, these analogues could be considered for the management of advanced prostate carcinoma.     

Array CGH analysis identifies two distinct subgroups of primary angiosarcoma of bone

Molecular genetic studies on vascular tumors are rare. Recently, possible involvement of MYC and KDR has been documented in a subset of angiosarcomas of soft tissue. We performed a cytogenetic analysis of primary angiosarcomas of bone (n = 13) and soft tissue (n = 5) using high density array‐comparative genomic hybridization (array‐CGH). Regions of interest were validated by fluorescence in situ hybridization (FISH). Antibodies for candidate genes (SKI, MYC, KDR, and MAPK9) were selected and immunohistochemistry was performed. Six angiosarcomas of bone and four angiosarcomas of soft tissue showed chromosomal losses, gains, and high level amplifications. Cluster analysis identified two groups: a group with a complex genetic profile and a group with only few genetic aberrations. Five regions of interest were selected, which were located at chromosome bands 1p36.23, 2q32‐34, 5q35, 8q24, and 17q21.32‐24.2. Interphase FISH confirmed the high‐level amplifications. Immunohistochemical analysis showed high expression of MYC (16/60), MAPK9 (63/69), and SKI (52/62). There were no differences between the two groups with regards to location, immunohistochemical expression nor survival. In summary, we identified two subgroups of angiosarcoma: those with few or no gross aberrations and those which show numerous genetic aberrations consisting of chromosomal losses, gains and high level amplifications or complex aberrations. The most common finding was amplification of 2q and 17q in both angiosarcoma of bone and soft tissue, suggesting overlap in tumorigenesis irrespective of their location. We show MYC amplification in primary angiosarcoma indicating this is not entirely specific for radiation‐induced angiosarcoma. © 2014 Wiley Periodicals, Inc.