High prevalence of serum antibodies reacting with simian virus 40 capsid protein mimotopes in patients affected by malignant pleural mesothelioma

Human malignant pleural mesothelioma (MPM) is considered a rare tumor, but recent estimations indicate that one-quarter million people will die of this neoplasm in Europe in the next three decades. The mineral asbestos is considered the main causative agent of this neoplasm. MPM is largely unresponsive to conventional chemotherapy/radiotherapy. In addition to asbestos exposure, genetic predisposition to asbestos carcinogenesis and to simian virus (SV)40 infection has also been suggested. SV40 is a DNA tumor virus found in some studies to be associated at high prevalence with MPM. SV40 sequences have also been detected, although at a lower prevalence than in MPM, in blood specimens from healthy donors. However, some studies have failed to reveal SV40 footprints in MPM and its association with this neoplasm. These conflicting results indicate the need for further investigations with new approaches. We report on the presence of antibodies in serum samples from patients affected by MPM that specifically react with two different SV40 mimotopes. The two SV40 peptides used in indirect ELISAs correspond to viral capsid proteins. ELISA with the two SV40 mimotopes gave overlapping results. Our data indicate that in serum samples from MPM-affected patients (n = 97), the prevalence of antibodies against SV40 viral capsid protein antigens is significantly higher (26%, P = 0.043) than in the control group (15%) represented by healthy subjects (n = 168) with the same median age (66 y) and sex. Our results suggest that SV40 is associated with a subset of MPM and circulates in humans.     

"It's a hair-dryer…No, it's a drill": misidentification-related false recognitions in younger and older adults

Memory for visual objects, although typically highly accurate, can be distorted, especially in older adults. Here we asked whether also erroneous identifications of visual objects subsequently corrected and replaced by a correct identification might induce false recognitions, and whether this is more likely to occur in older people. For this aim a new paradigm was developed. In the first phase, participants performed a visual object identification task with degraded pictures of objects and produced correct and false but subsequently corrected identifications. In the second phase, participants performed a surprise recognition task in which also false identifications were presented. False identifications elicited false recognitions, with a stronger and more reliable effect in elderly participants, suggesting that correcting the initial visual error is not sufficient to correct the memory for the experience. Moreover, misidentification-related false recognitions coexisted in memory along with correct recognitions of correct identifications. These findings are discussed in relation with age-related deficits in memory updating and strategic retrieval.