Erratum to “Associations between psychotic-like experiences and mental health status and other psychopathologies among Japanese early teens”[Schizophrenia Research 99 (1–3) (2008) 125–133]

Psychotic-like experiences (PLEs) are considered predictive of mental health problems later in life. However, little has been known about the mental health status and psychopathological distress in adolescents with PLEs in the general population. To investigate the associations between PLEs and mental health status or psychopathologies in a community sample of adolescents in a school-based cross-sectional fashion, PLEs were studied using a self-rating questionnaire in 5073 Japanese junior-high school students aged 12–15 years. Mental health status was evaluated using the 12-item General Health Questionnaire (GHQ-12). Psychopathologies, lifestyle, victimization, and interpersonal and help-seeking attitudes were also studied using a self-rating questionnaire. Fifteen percent of the students reported definitely having experienced at least one PLE. A dose-response relationship between the severity of PLEs and the prevalence of poor mental health status was observed. PLEs were also significantly associated with psychopathologies (strong anxiety in the classroom: OR = 1.4, 95% CI 1.2–1.6; suicidal ideation: OR = 2.1, 95% CI 1.8–2.4; self-harm behaviors: OR = 1.4, 95% CI 1.0–1.9; difficulty falling asleep due to hypersensitivity to environmental noise: OR = 1.7, 95% CI 1.4–2.0; difficulty concentrating due to hypersensitivity to environmental noise: OR = 1.5, 95% CI 1.3–1.8; physically assaulting others: OR = 1.3, 95% CI 1.0–1.5; bullying others, OR = 1.3, 95% CI 1.1–1.5; irritability when exchanging e-mails: OR = 1.3, 95% CI 1.0–1.6). Adolescents with PLEs in the community suffer from a wide range of psychopathological problems during crucial developmental periods.     

Neurotoxic effects of MDMA (“ecstasy”) administration to neonatal rats

3,4-Methylenedioxymethamphetamine damages fine serotonergic fibers and nerve terminals in adult organisms. Developing animals seem to be less susceptible to this effect, possibly due to a lack of drug-induced hyperthermia. We tested this hypothesis by producing hyperthermia in neonatal rats for 2 h after each of twice-daily MDMA (10 mg/kg s.c.) or saline injections administered from postnatal days 1–4. Other drug-treated and control litters were maintained at normothermic temperatures following injection. Changes in forebrain serotonergic innervation were assessed at postnatal day 25 (serotonin transporter binding and serotonin levels), postnatal day 60 (serotonin transporter binding), and 9 months of age (serotonin transporter immunohistochemistry). We also determined the influence of MDMA treatment on apoptotic activity by means of immunohistochemistry for cleaved caspase-3 at postnatal day 5. The hippocampus showed significant MDMA-related reductions in serotonergic markers at postnatal day 25 and postnatal day 60. At 9 months, there was no effect of prior MDMA exposure on serotonin transporter-immunoreactive fiber density in the hippocampus; however, significant reductions in fiber density were observed in two neocortical areas and a hyperinnervation was found in the caudate-putamen and nucleus accumbens shell. MDMA treatment also produced a two-fold increase in the number of cleaved caspase-3-immunoreactive cells in the rostral forebrain and hippocampus. All of these effects were completely independent of pup body temperature. These findings demonstrate that neonatal MDMA administration exposure stimulates apoptotic cell death in various forebrain areas and also leads to a long-term reorganization of the forebrain serotonergic innervation. Consequently, offspring of MDMA-using women may be at heightened risk for abnormal neural and behavioral development.