The cheek of a cheater: Effects of posing the left and right hemiface on the perception of trustworthiness

Our cognitive mechanisms are designed to detect cheaters in social exchanges. However, cheater detection can be thwarted by a posed smile, which cheaters display with greater emotional intensity than cooperators. The present study investigated the role of hemifacial asymmetries in the perception of trustworthiness using face photographs with left and right cheek poses. Participants (N?=?170) observed face photographs of cheaters and cooperators in an economic game. In the photographs, models expressed happiness or anger and turned slightly to the left or right to show their left or right cheeks to the camera. When the models expressed anger on their faces, cheaters showing the right cheek were rated as less trustworthy than cooperators (irrespective of cheeks shown) and cheaters showing the left cheek. When the models expressed happiness, trustworthiness ratings increased and did not differ between cheaters and cooperators, and no substantial asymmetries were observed. These patterns were replicated even when the face photographs were mirror-reversed. These results suggest that a cheater’s fake smile conceals an uncooperative attitude that is displayed in the right hemiface, ultimately disguising cheater detection.     

Characterization of skin blister fluids from children with Epstein–Barr virus‐associated lymphoproliferative disease

Epstein–Barr virus (EBV)‐associated T‐ or natural killer (NK)‐cell lymphoproliferative disease (LPD) is a heterogeneous group of disorders characterized by chronic proliferation of EBV‐infected lymphocytes. Patients may present with severe skin manifestations, including hypersensitivity to mosquito bites (HMB) and hydroa vacciniforme (HV)‐like eruption, which are characterized by blister formation and necrotic ulceration. Skin biopsy specimens show inflammatory reactions comprising EBV‐infected lymphocytes. However, blister fluids have not been fully assessed in patients with this disease. Blister fluids were collected from three patients with EBV‐associated LPD: two with HMB and one with HV. Immunophenotyping of blister lymphocytes and measurement of tumor necrosis factor (TNF)‐α in blister fluids were performed. The patients with HMB and HV exhibited markedly increased percentages of NK and γδ T cells, respectively, in both peripheral blood and blister fluids. These NK and γδ T cells strongly expressed the activation marker human leukocyte antigen‐DR and were considered to be cellular targets of EBV infections. TNF‐α was highly elevated in all blister fluids. Severe local skin reactions of EBV‐associated LPD may be associated with infiltrating EBV‐infected lymphocytes and a high TNF‐α concentration in blister fluids.     

A Novel Approach to Detecting Postpartum Hemorrhage Using Contrast-Enhanced Ultrasound

The aim of this study was to estimate the efficacy of contrast-enhanced ultrasound (CEUS) in detecting postpartum hemorrhage (PPH) after cesarean section. This is the first study of CEUS in obstetric hemorrhage. A total of 37 patients, operated at Nagoya University Hospital, underwent CEUS. We evaluated the findings of CEUS, which were qualitatively defined as positive when pooling or leakage of contrast agent was observed in the uterine cavity, by measuring the amount of bleeding during the first 4 h after cesarean section. The time–intensity curve patterns of leaked contrast agents were also analyzed for quantitative prediction of the amount of blood loss. Significant differences between the excessive hemorrhage (N = 7) and non-excessive hemorrhage groups (N = 30) were noted in the occurrence of positive CEUS (p = 0.011). Additionally, mean postpartum blood loss markedly increased in patients with a positive CEUS (p = 0.002). From a quantitative perspective, the time until leakage of contrast agents was detected correlated with the amount of bleeding, but the other characteristics of the time–intensity curve pattern did not provide valuable information. In conclusion, CEUS, which enables bedside assessment and rapid diagnosis, is a promising strategy for the detection of PPH.