Exposure to Herpes Simplex Virus Type 1 and Cognitive Impairments in Individuals With Schizophrenia.

1Department of Psychiatry, University of Pittsburgh School of Medicine, Western Psychiatric Institute and Clinic, Pittsburgh, PA.
Schizophrenia Bulletin (Impact Factor: 8.61). 04/2012; DOI: 10.1093/schbul/sbs046
Source: PubMed

ABSTRACT Latent infection with neurotropic herpes viruses, such as herpes simplex virus, type 1 (HSV1), has been generally considered benign in most immunocompetent individuals except for rare cases of encephalitis. However, several recent studies have shown impaired cognitive functions among individuals with schizophrenia exposed to HSV1 compared with schizophrenia patients not exposed to HSV1. Such impairments are robust and are prominently observed in working memory, verbal memory, and executive functions. Brain regions that play a key role in the regulation of these domains have shown smaller volumes, along with correlation between these morphometric changes and cognitive impairments in schizophrenia. One study noted temporal decline in executive function and gray matter loss among HSV1-exposed first-episode antipsychotic-naïve schizophrenia patients. Furthermore, a proof-of-concept double-blind placebo-controlled trial indicated improvement in cognitive performance following supplemental anti-herpes-specific medication among HSV1 seropositive schizophrenia patients. Cross-sectional studies have also identified an association between HSV1 exposure and lesser degrees of cognitive impairment among healthy control individuals and patients with bipolar disorder. These studies fulfill several Bradford-Hill criteria, suggesting etiological links between HSV1 exposure and cognitive impairment. Exposure to other human herpes viruses such as cytomegalovirus and herpes simplex virus type 2 (HSV2) may also be associated with cognitive impairment, but the data are less consistent. These studies are reviewed critically and further lines of enquiry recommended. The results are important from a public health perspective, as HSV1 exposure is highly prevalent in many populations.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: Latent chronic infection with Toxoplasma gondii (T. gondii), a common neurotropic pathogen, has been previously linked with suicidal self-directed violence (SSDV). We sought to determine if latent infection with T gondii is associated with trait aggression and impulsivity, intermediate phenotypes for suicidal behavior, in psychiatrically healthy adults. Methods: Traits of aggression and impulsivity were analyzed in relationship to IgG antibody seropositivity for T gondii and two other latent neurotropic infections, herpes simplex virus 1 (HSV1) and cytomegalovirus (CMV). One thousand community-residing adults residing in the Munich metropolitan area with no Axis I or II conditions by SCID for DSM-IV (510 men, 490 women, mean age 53.6 +/- 15.8, range 20-74). Plasma samples were tested for IgG antibodies to T. gondii, HSV-1 and CMV by ELISA. Self-reported ratings of trait aggression scores (Questionnaire for Measuring Factors of Aggression [FAF]) and trait impulsivity (Sensation-Seeking Scale-V [SSS-V]) were analyzed using linear multivariate methods. Results: T gondii IgG seropositivity was significantly associated with higher trait reactive aggression scores among women (p < .01), but not among men. T. gondii-positivity was also associated with higher impulsive sensation-seeking (SSS-V Disinhibition) among younger men (p < .01) aged 20-59 years old (median age = 60). All associations with HSV-1 and CMV were not significant. Conclusions: Aggression and impulsivity, personality traits considered as endophenotypes for SSDV, are associated with latent T gondii infection in a gender and age-specific manner, and could be further investigated as prognostic and treatment targets in 7: gondii-positive individuals at risk for SSDV. Published by Elsevier Ltd.
    Journal of Psychiatric Research 09/2014; 60. DOI:10.1016/j.jpsychires.2014.09.019 · 4.09 Impact Factor
  • Source
    Frontiers in Cellular Neuroscience 09/2013; 7:153. DOI:10.3389/fncel.2013.00153 · 4.18 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cu-to-Cu interconnects were achieved by pressureless low temperature sintering of Ag nanoparticles for electronic packaging. Ag nanoparticles could be sintered so long as the chemical bonds by which organic shells connected with Ag nanoparticles were broken with no necessity that organic shells completely decomposed, which provided a way to lower bonding temperature. The pinecone-like recrystallization morphology of sintering Ag nanoparticles was observed by transmission electron microscopy, which resulted from the residuals of organic shells by sintering process. The thermal conductivity of sintered Ag nanoparticles was affected strongly by the recrystallization morphology because of grain boundary scattering effect. The shear strengths of joints reached 17-25 MPa at temperatures ranging from 150 °C to 200 °C.
    Electronic Materials and Packaging (EMAP), 2012 14th International Conference on; 01/2012