The Community Assessment of Psychic Experiences-Positive scale (CAPE-P15) accurately classifies and differentiates psychotic experience levels in adolescents from the general population.

BACKGROUND: There is increasing interest in studying psychotic symptoms in non-clinical populations, with the Community Assessment of Psychic Experiences-Positive scale (CAPE-P15) being one of the self-screening questionnaires used most commonly for this purpose. Further research is needed to evaluate the ability of the scale to accurately identify and classify positive psychotic experiences (PE) in the general population. AIM: To provide psychometric evidence about the accuracy of the CAPE-P15 for detecting PE in a sample of Chilean adolescents from the general population and classifying them according to their PE severity levels. METHOD: We administered the CAPE-P15 to a general sample of 1594 students aged 12 to 19. Based on Item Response Theory (IRT), we tested the accuracy of the instrument using two main parameters: difficulty and discrimination power of the 15 items. RESULTS: We found that the scale provides very accurate information about PE, particularly for high PE levels. The items with the highest capability to determine the presence of the latent trait were those assessing perceptual anomalies (auditory and visual hallucinations), bizarre experiences (a double has taken the place of others; being controlled by external forces), and persecutory ideation (conspiracy against me). CONCLUSIONS: The CAPE-P15 is an accurate and suitable tool to screen PE and to accurately classify and differentiate PE levels in adolescents from the general population. Further research is needed to better understand how maladaptive psychological mechanisms influence relationships between PE and suicidal ideation (SI) in the general population.

Angiostrongylus cantonensis causes cognitive impairments in heavily infected BALB/c and C57BL/6 mice.

BACKGROUND: Parasitic infections may cause significant effects on behavior, learning, and memory of the host. In the brain of mice heavily infected with Angiostrongylus cantonensis, severe damage has been observed in the hippocampus. This component has been considered to have associations with spatial learning and memory in humans and vertebrates. This study was designed to determine the impairments in behavior, learning, and memory in BALB/c and C57BL/6 mice heavily infected with the parasite. METHODS: Each mouse was inoculated with 50 third-stage larvae of A. cantonensis. After infection, daily changes in weight and dietary consumption, worm recoveries and survival rates were determined. The forced swimming test, open field test, and Morris water maze test were employed to evaluate depression- and anxiety-like behavior as well as impairments in spatial learning and memory, respectively. RESULTS: The worm recovery rate in the BALB/c mice was significantly lower than that of C57BL/6 mice from day 14 post-infection. The survival rate in infected BALB/c mice decreased to 0% by day 25 whereas those with swim-training survived three more days. On day 42, the C57BL/6 mice had a survival rate of 85.7% in the swimming group and 70% in the non-swimming group. Significant differences were found in weight between infected and non-infected BALB/c and C57BL/6 mice from day 13 and day 12, respectively with corresponding changes in their dietary consumption. Depression-like behavior was found in the infected BALB/c mice but not in C57BL/6 mice. However, anxiety-like behavior was found to occur only in C57BL/6 mice. Impaired spatial learning and memory were also found in the two strains of mice which occurred from day 14 post-infection. CONCLUSIONS: Results of this study indicate that A. cantonensis causes depression, anxiety, and impairments in spatial learning and memory in heavily infected mice. Moreover, significantly higher severity was observed in the Th-2 dominant BALB/c mice.

Depression and Toxoplasma gondii infection: assess the possible relationship through a seromolecular case-control study.

Depression disorder is one of the most common psychological recognitions that characterized by sadness, low self-confidence, and disinterest in every activity. Considering evidence showing the effects of toxoplasmosis on the psychological disease, this study conducted to investigate the serological and molecular aspects of Toxoplasma gondii infection among patients with depression. In this study, after selecting the patients with depression and control groups under the supervision of a psychologist, the blood samples were collected and the serum samples and buffy coat were separated. The specific anti-Toxoplasma IgG antibodies in serum samples were evaluated using the commercial ELISA kit. Then the desired region of the Toxoplasma B1 gene was amplified using the specific primers. To confirm the specificity of primers to amplify the B1 gene of Toxoplasma, the extracted PCR product was sequenced. The overall prevalence of toxoplasmosis in patients with depression was 59.8 and 60.19% by ELISA and PCR, respectively. In the control group, the prevalence of Toxoplasma was 56.3 and 40.2% by serology and PCR. There was a significant correlation between the prevalence of toxoplasmosis and depression. Moreover, a significant difference was found between the variables of age, sex, kind of nutrition, level of education and toxoplasmosis among the two cases and control groups. The higher prevalence of Toxoplasma infection among patients with depression compared with the control group indicates the probable impact of this parasite on depression and exacerbates its symptoms, which requires special attention of specialist physicians and patient's relatives.

Disturbance in human gut microbiota networks by parasites and its implications in the incidence of depression.

If you think you are in control of your behavior, think again. Evidence suggests that behavioral modifications, as development and persistence of depression, maybe the consequence of a complex network of communication between macro and micro-organisms capable of modifying the physiological axis of the host. Some parasites cause significant nutritional deficiencies for the host and impair the effectiveness of cognitive processes such as memory, teaching or non-verbal intelligence. Bacterial communities mediate the establishment of parasites and vice versa but this complexity approach remains little explored. We study the gut microbiota-parasite interactions using novel techniques of network analysis using data of individuals from two indigenous communities in Guerrero, Mexico. Our results suggest that Ascaris lumbricoides induce a gut microbiota perturbation affecting its network properties and also subnetworks of key species related to depression, translating in a loss of emergence. Studying these network properties changes is particularly important because recent research has shown that human health is characterized by a dynamic trade-off between emergence and self-organization, called criticality. Emergence allows the systems to generate novel information meanwhile self-organization is related to the system's order and structure. In this way, the loss of emergence means a depart from criticality and ultimately loss of health.

Latent toxoplasma infection in real-world schizophrenia: Results from the national FACE-SZ cohort.

OBJECTIVE: Latent Toxoplasma infection has been associated with widespread brain immune activation, increased blood brain barrier permeability, neural disruption, increased dopamine release in dopaminergic neurons, with NMDA activation and with schizophrenia (SZ) onset risk. Toxoplasma has been suggested to be a source of chronic low-grade inflammation and this inflammation has been associated with cognitive impairment in SZ. The objective of the present study were (i) to determine if latent Toxoplasma infection was associated with specific clinical features in stabilized SZ subjects, with cognitive impairment and with increased low-grade peripheral inflammation and (ii) to determine if Treatments with Anti-Toxoplasmic Activity (TATA) were associated with improved outcomes in subjects with latent Toxoplasma infection. METHODS: A comprehensive 2 daylong clinical and neuropsychological battery was administered in 250 SZ subjects included between 2015 and 2017 in the national FondaMental Expert Center (FACE-SZ) Cohort. Solid phase-enzyme microplate immunoassay methods were used to measure IgG class of antibodies to T. gondii in blood sample. Latent Toxoplasma infection was defined by T. gondii IgG ratio ≥0.8, equivalent to ≥10 international units. Chronic peripheral inflammation was defined by highly sensitive C reactive protein blood level ≥ 3 mg/L. RESULTS: Latent Toxoplasma infection has been found in 184 (73.6%) of this national multicentric sample. In the multivariate analyses, latent Toxoplasma infection has been significantly associated with higher PANSS negative (aOR = 1.1 [1.1-1.1], p = 0.04) and excitement subscores (aOR = 1.3 [1.1-1.6], p = 0.01), with two specific symptoms (i.e., reference delusion (aOR = 3.6 [1.2-10.6] p = 0.01) and alogia (aOR = 16.7 [2.0-134.7], p = 0.008)) and with chronic low-grade peripheral inflammation (27.2% vs. 7.6%, aOR = 3.8 [1.4-10.3], p = 0.004). Extrapyramidal symptoms remained significantly associated with latent Toxoplasma infection. On the opposite, no significant association of latent Toxoplasma infection with age, gender, age at SZ onset, suicide behavior or cognitive deficits has been found in these models (all p > 0.05). TATA were associated with lower depressive symptoms (aOR = 0.8[0.7-0.9], p = 0.01), and with lower rates of chronic peripheral inflammation (20.9% vs. 48.6%, aOR = 3.5 [1.5-7.9], p = 0.003) but not with higher cognitive scores (p > 0.05). CONCLUSION: The present findings suggest that Toxoplasma is almost 3 times more frequent in SZ population compared to general population in France. The potential cerebral underpinnings of the association of latent Toxoplasma infection and the above-mentioned outcomes have been discussed. Future studies should confirm that TATA may be effective to reduce Toxoplasma-associated depressive symptoms and low-grade peripheral inflammation.

Lack of association between Toxoplasma gondii exposure and depression in pregnant women: a case-control study.

BACKGROUND: Very little is known about the link of T. gondii infection and depression. Through an age-, gender-, and month of pregnancy-matched case-control study, we determined the association of T. gondii infection and depression in pregnant women. METHODS: We studied 200 pregnant women with depression and 200 pregnant women without depression attended in a public hospital in Durango City, Mexico. Pregnant women were tested for the presence of anti-Toxoplasma IgG antibodies using an enzyme-linked immunoassay (EIA), and IgG seropositive women were further tested for the presence of IgM using an EIA. IgM positivity by EIA was further analyzed by enzyme-linked fluorescence assay (ELFA). RESULTS: Anti-T. gondii IgG antibodies were found in 9 (4.5%) of the 200 cases and in 12 (6.0%) of the 200 controls (OR = 0.73; 95% CI: 0.30-1.79; P = 0.50). The frequency of high (>150 IU/ml) anti-T. gondii IgG levels was similar in cases and in controls (OR = 1.20; 95% CI: 0.36-4.01; P = 0.75). Two women were positive for IgM by EIA but both were negative by ELFA. CONCLUSIONS: We did not find serological evidence of an association between T. gondii infection and depression in pregnant women attended in a public hospital in Durango City, Mexico. Since an association of T. gondii and depression in pregnancy has been reported in the U.S. previously, further research to elucidate the role of T. gondii in prenatal depression should be conducted.

Depressive symptomatology and grief in Spanish women who have suffered a perinatal loss.

BACKGROUND: Perinatal grief differs from other types of mourning. Two goals were set: to describe the progression of the process of grief and the symptoms of depression throughout the year following perinatal loss, and to study its association with socio-economic and obstetric factors. METHOD: The study involved the participation of 70 women who had suffered a medical termination of pregnancy or a prenatal/postnatal death. Three assessments were made after the loss (after 1 month, 6 months and 1 year) with the Perinatal Grief Scale (PGS) to assess grief and the Beck Depression Inventory (BDI) for depressive symptomatology. RESULTS: Symptoms pertaining to grief and depression were observed in the first month after the loss, and a significant decrease in scores over the two follow-ups. No significant differences were observed in grief and depression depending on the type of loss, no significant associations were found with the age of the mother, her socioeconomic level, or obstetric factors (week of gestation of the loss, having a child or having suffered a previous miscarriage). CONCLUSIONS: Perinatal grief is a complex construct, with multiple variables involved, and one which involves significant emotional discomfort.

Behavioural alterations are independent of sickness behaviour in chronic experimental Chagas disease.

The existence of the nervous form of Chagas disease is a matter of discussion since Carlos Chagas described neurological disorders, learning and behavioural alterations in Trypanosoma cruzi-infected individuals. In most patients, the clinical manifestations of the acute phase, including neurological abnormalities, resolve spontaneously without apparent consequence in the chronic phase of infection. However, chronic Chagas disease patients have behavioural changes such as psychomotor alterations, attention and memory deficits, and depression. In the present study, we tested whether or not behavioural alterations are reproducible in experimental models. We show that C57BL/6 mice chronically infected with the Colombian strain of T. cruzi (150 days post-infection) exhibit behavioural changes as (i) depression in the tail suspension and forced swim tests, (ii) anxiety analysed by elevated plus maze and open field test sand and (iii) motor coordination in the rotarod test. These alterations are neither associated with neuromuscular disorders assessed by the grip strength test nor with sickness behaviour analysed by temperature variation sand weight loss. Therefore, chronically T. cruzi-infected mice replicate behavioural alterations (depression and anxiety) detected in Chagas disease patients opening an opportunity to study the interconnection and the physiopathology of these two biological processes in an infectious scenario.

Behavioural alterations are independent of sickness behaviour in chronic experimental Chagas disease

The existence of the nervous form of Chagas disease is a matter of discussion since Carlos Chagas described neurological disorders, learning and behavioural alterations in Trypanosoma cruzi-infected individuals. In most patients, the clinical manifestations of the acute phase, including neurological abnormalities, resolve spontaneously without apparent consequence in the chronic phase of infection. However, chronic Chagas disease patients have behavioural changes such as psychomotor alterations, attention and memory deficits, and depression. In the present study, we tested whether or not behavioural alterations are reproducible in experimental models. We show that C57BL/6 mice chronically infected with the Colombian strain of T. cruzi (150 days post-infection) exhibit behavioural changes as (i) depression in the tail suspension and forced swim tests, (ii) anxiety analysed by elevated plus maze and open field test sand and (iii) motor coordination in the rotarod test. These alterations are neither associated with neuromuscular disorders assessed by the grip strength test nor with sickness behaviour analysed by temperature variation sand weight loss. Therefore, chronically T. cruzi-infected mice replicate behavioural alterations (depression and anxiety) detected in Chagas disease patients opening an opportunity to study the interconnection and the physiopathology of these two biological processes in an infectious scenario.

Child Gain Approach and Loss Avoidance Behavior: Relationships With Depression Risk, Negative Mood, and Anhedonia.

OBJECTIVE: Reduced reward responsiveness and altered response to loss of reward are observed in adults with major depressive disorder (MDD) and adolescents at increased risk for MDD based on family history. However, it is unclear whether altered behavioral responsiveness to reward/loss is a lifelong marker of MDD risk, which is evident before the normative adolescent increase in incentive responding. METHOD: Healthy 7- to 10-year-old children of mothers with MDD (high risk: n = 27) or without MDD (low risk: n = 42) performed 2 signal detection tasks assessing response bias toward reward (approach) and away from loss (avoidance). Differences in approach/avoidance were related to MDD risk, child general depressive symptoms (maternal report), child-reported anhedonic symptoms, and child-reported negative mood symptoms via repeated-measures analysis of variance. RESULTS: MDD risk did not significantly relate to gain approach or loss avoidance. However, within high-risk children, higher numbers of maternal depressive episodes predicted blunted loss avoidance. Blunted gain approach was related to elevated anhedonic symptoms, whereas enhanced loss avoidance was related to elevated negative mood. Elevated negative mood was further related to blunted gain approach in high-risk children but related to enhanced gain approach in low-risk children. CONCLUSION: In children, individual differences in specific depressive symptoms and recurrence of maternal depression significantly predicted gain approach/loss avoidance, but the presence/absence of maternal MDD did not. Child depressive symptoms characterized by low positive affect (anhedonia) were related to blunted gain responsiveness, whereas elevated depressed/negative mood was related to enhanced loss responsiveness. Findings suggest that relations between gain approach and negative mood may be an important distinction between those at high versus low risk for MDD.

Possible link between Toxoplasma gondii and the anosmia associated with neurodegenerative diseases.

Toxoplasma gondii is an intracellular protozoan infecting 30% to 50% of global human population. Recently, it was suggested that chronic latent neuroinflammation caused by the parasite may be responsible for the development of several neurodegenerative diseases manifesting with the loss of smell. Studies in animals inoculated with the parasite revealed cysts in various regions of the brain, including olfactory bulb. Development of behavioral changes was paralleled by the preferential persistence of cysts in defined anatomic structures of the brain, depending on the host, strain of the parasite, its virulence, and route of inoculation. Olfactory dysfunction reported in Alzheimer's disease, multiple sclerosis, and schizophrenia was frequently associated with the significantly increased serum anti-T gondii immunoglobulin G antibody levels. Damage of the olfactory system may be also at least in part responsible for the development of depression because T gondii infection worsened mood in such patients, and the olfactory bulbectomized rat serves as a model of depression.

Increasing the validity of experimental models for depression.

Major depressive disorder (MDD) is a central nervous system disorder characterized by the culmination of profound disturbances in mood and affective regulation. Animal models serve as a powerful tool for investigating the neurobiological mechanisms underlying this disorder; however, little standardization exists across the wide range of available modeling approaches most often employed. This review will illustrate some of the most challenging obstacles faced by investigators attempting to associate depressive-like behaviors in rodents with symptoms expressed in MDD. Furthermore, a novel series of depressive-like criteria based on correlating behavioral endophenotypes, novel in vivo neurophysiological measurements, and molecular/cellular analyses within multiple brain are proposed as a potential solution to overcoming this barrier. Ultimately, linking the neurophysiological and cellular/biochemical actions that contribute to the expression of a defined MDD-like syndrome will dramatically extend the translational value of the most valid animal models of MDD.

Neuropsychiatric disease and Toxoplasma gondii infection.

Toxoplasma gondii infects approximately 30% of the world's population, but causes overt clinical symptoms in only a small proportion of people. In recent years, the ability of the parasite to manipulate the behaviour of infected mice and rats and alter personality attributes of humans has been reported. Furthermore, a number of studies have now suggested T. gondii infection as a risk factor for the development of schizophrenia and depression in humans. As T. gondii forms cysts that are located in various anatomical sites including the brain during a chronic infection, it is well placed anatomically to mediate these effects directly. The T. gondii genome is known to contain 2 aromatic amino acid hydroxylases that potentially could directly affect dopamine and/or serotonin biosynthesis. However, stimulation of the immune response has also recently been associated with mood and behavioural alterations in humans, and compounds designed to alter mood, such as fluoxetine, have been demonstrated to alter aspects of immune function. Herein, the evidence for T.-gondii-induced behavioural changes relevant to schizophrenia and depression is reviewed. Potential mechanisms responsible for these changes in behaviour including the role of tryptophan metabolism and the hypothalamic-pituitary-adrenal axis are discussed.

Dog interaction with persons receiving institutional geriatric care.

A prospective study of 66 geriatric residents in 2 facilities was conducted to quantitate people-dog interactions. Residents were assigned randomly to sessions with dog activity and to sessions with other activity in a crossover design. This study involved a 12-week prestudy activity period and two 12-week activity periods, one before crossover and one after crossover. Systolic and diastolic blood pressures, psychologic evaluation of case histories, and other health and social variables were measured on all residents for dog activity and other combinations of programmed activity sessions. Frequence of attendance in both facilities was higher at dog activity sessions than at other activity sessions (P less than 0.01). Resident systolic blood pressures were lower in one facility during dog activity (P less than 0.02). Combined pre- and postactivity systolic and diastolic blood pressures at the same facility were lower when residents had 12 weeks of dog activity before 12 weeks of other activity (P less than 0.04). There were no significant differences in residents' blood pressures between measurements before and after dog activity (treatment mode) or between measurements before and after other activity. Psychologic scores of residents in both facilities were not significantly different between periods of the study. Of the 9 types of interaction between the residents and the dog, grooming and touching were the 2 most commonly used by residents.