Evaluation of QSAR models for predicting mutagenicity: outcome of the Second Ames/QSAR international challenge project.

Quantitative structure-activity relationship (QSAR) models are powerful in silico tools for predicting the mutagenicity of unstable compounds, impurities and metabolites that are difficult to examine using the Ames test. Ideally, Ames/QSAR models for regulatory use should demonstrate high sensitivity, low false-negative rate and wide coverage of chemical space. To promote superior model development, the Division of Genetics and Mutagenesis, National Institute of Health Sciences, Japan (DGM/NIHS), conducted the Second Ames/QSAR International Challenge Project (2020-2022) as a successor to the First Project (2014-2017), with 21 teams from 11 countries participating. The DGM/NIHS provided a curated training dataset of approximately 12,000 chemicals and a trial dataset of approximately 1,600 chemicals, and each participating team predicted the Ames mutagenicity of each trial chemical using various Ames/QSAR models. The DGM/NIHS then provided the Ames test results for trial chemicals to assist in model improvement. Although overall model performance on the Second Project was not superior to that on the First, models from the eight teams participating in both projects achieved higher sensitivity than models from teams participating in only the Second Project. Thus, these evaluations have facilitated the development of QSAR models.

The COVID-19 pandemic's impact on worry and medical disruptions reported by individuals with chromosome 22q11.2 copy number variants and their caregivers.

BACKGROUND: The world has suffered immeasurably during the COVID-19 pandemic. Increased distress and mental and medical health concerns are collateral consequences to the disease itself. The Genes to Mental Health (G2MH) Network consortium sought to understand how individuals affected by the rare copy number variations of 22q11.2 deletion and duplication syndrome, associated with neurodevelopmental/neuropsychiatric conditions, were coping. The article focuses on worry and disruptions in medical care caused by the pandemic. METHODS: The University of Pennsylvania COVID-19 Stressor List and care disruption questions were circulated by 22 advocacy groups in English and 11 other languages. RESULTS: A total of 512 people from 23 countries completed the survey; most were caregivers of affected individuals. Worry about family members acquiring COVID-19 had the highest average endorsed worry, whilst currently having COVID-19 had the lowest rated worry. Total COVID-19 worries were higher in individuals completing the survey towards the end of the study (later pandemic wave); 36% (n = 186) of the sample reported a significant effect on health due to care interruption during the pandemic; 44% of individuals (n = 111) receiving care for their genetic syndrome in a hospital setting reported delaying appointments due to COVID-19 fears; 12% (n = 59) of the sample reported disruptions to treatments; and of those reporting no current disruptions, 59% (n = 269) worried about future disruptions if the pandemic continued. Higher levels of care disruptions were related to higher COVID-19 worries (Ps < 0.005). Minimal differences by respondent type or copy number variation type emerged. CONCLUSIONS: Widespread medical care disruptions and pandemic-related worries were reported by individuals with 22q11.2 syndrome and their family members. Reported worries were broadly consistent with research results from prior reports in the general population. The long-term effects of COVID-19 worries, interruptions to care and hospital avoidance require further study.

Early second-trimester three-dimensional transvaginal neurosonography of fetal midbrain and hindbrain: normative data and technical aspects.

OBJECTIVES: To provide a detailed description of the sonographic appearance and development of various fetal structures of the midbrain and hindbrain (MBHB) during the early second trimester, and to evaluate the impact of the frequency of the transvaginal sonography (TVS) transducer on the early recognition of these structures. METHODS: This was a retrospective analysis of three-dimensional volumetric datasets of the MBHB from apparently normal fetuses at 14-19 gestational weeks, acquired by TVS in the midsagittal view through the posterior fontanelle. Using a multiplanar approach, we measured the tectal thickness and length, aqueductal thickness, tegmental thickness and width and height of the Blake's pouch (BP) neck. In addition, we assessed the existence of early vermian fissures, the linear shape of the brainstem and the components of the fastigium. The correlation between gestational age according to last menstrual period and sonographic measurements of MBHB structures was evaluated using Pearson's correlation (r). A subanalysis was performed to assess the performance of a 5-9-MHz vs a 6-12-MHz TVS transducer in visualizing the MBHB structures in the early second trimester. RESULTS: Sixty brain volumes were included in the study, obtained at a mean gestational age of 16.2 weeks (range, 14.1-19.0 weeks), with a transverse cerebellar diameter range of 13.0-19.8 mm. We found a strong correlation between gestational age and all MBHB measurements, with the exception of the tectal, tegmental and aqueductal thicknesses, for which the correlation was moderate. There was good-to-excellent intraobserver and moderate-to-good interobserver correlation for most MBHB measurements. We observed that the BP neck was patent in all fetuses between 14 and 18 weeks with decreasing diameter, and that the aqueductal thickness was significantly smaller at ≥ 18 weeks compared with at < 16 weeks. The early vermian fissures and the linear shape of the brainstem were present in all fetuses from 14 weeks. We found that, in the early second trimester, the horizontal arm of the presumed 'fastigium' evolves from the fourth ventricular choroid plexus and not the posterior vermis, indicating that this is not the fastigium. Standard- and high-resolution TVS transducers performed similarly in the assessment of MBHB anatomy. CONCLUSION: Detailed early second-trimester assessment of the MBHB is feasible by transvaginal neurosonography and provides reference data which may help in the early detection of brain pathology involving the MBHB. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Normal cavum veli interpositi at 14-17 gestational weeks: three-dimensional and Doppler transvaginal neurosonographic study.

OBJECTIVES: To provide evidence to support the hypothesis that the midline cyst-like fluid collection that is frequently observed on fetal brain ultrasound (US) imaging during the early second trimester represents a normal transient cavum veli interpositi (CVI). METHODS: This was a retrospective analysis of 89 three-dimensional normal fetal brain volumes, acquired by transvaginal US imaging in 87 pregnant women between 14 and 17 gestational weeks. The midsagittal view was studied using multiplanar imaging, and the maximum length of the fluid collection located over (dorsal to) the tela choroidea of the third ventricle was measured. We calculated the correlation of the transverse cerebellar diameter (TCD) and of the maximum length of the fluid collection with gestational age according to last menstrual period. Color Doppler images were analyzed to determine the location of the internal cerebral veins with respect to the location of the fluid collection. Reports of the second-trimester anatomy scan at 22-24 weeks were also reviewed. RESULTS: Interhemispheric fluid collections of various sizes were found in 55% (49/89) of the volumes (mean length, 5 (range, 3.0-7.8) mm). There was a strong correlation between TCD and gestational age (Pearson's correlation, 0.862; P < 0.001). There was no correlation between maximum fluid length and gestational age (Pearson's correlation, -0.442; P = 0.773). Color Doppler images were retrieved in 32 of the 49 fetuses; in 100% of these, the internal cerebral veins coursed within the echogenic roof of the third ventricle. The midline structures were normal at the 22-24-week scan in all cases. CONCLUSIONS: In approximately half of normal fetuses, during the evolution of the midline structures of the brain, various degrees of fluid accumulate transiently in the velum interpositum, giving rise to a physiologic CVI. Patients should be reassured that this is a normal phenomenon in the early second trimester that, if an isolated finding, has no influence on fetal brain development. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Association among income loss, financial strain and depressive symptoms during COVID-19: evidence from two longitudinal studies.

BACKGROUND: The COVID-19 pandemic has major ramifications for global health and the economy, with growing concerns about economic recession and implications for mental health. Here we investigated the associations between COVID-19 pandemic-related income loss with financial strain and mental health trajectories over a 1-month course. METHODS: Two independent studies were conducted in the U.S and in Israel at the beginning of the outbreak (March-April 2020, T1; N = 4 171) and at a 1-month follow-up (T2; N = 1 559). Mixed-effects models were applied to assess associations among COVID-19-related income loss, financial strain, and pandemic-related worries about health, with anxiety and depression, controlling for multiple covariates including pre-COVID-19 income. FINDINGS: In both studies, income loss and financial strain were associated with greater depressive symptoms at T1, above and beyond T1 anxiety, worries about health, and pre-COVID-19 income. Worsening of income loss was associated with exacerbation of depression at T2 in both studies. Worsening of subjective financial strain was associated with exacerbation of depression at T2 in one study (US). INTERPRETATION: Income loss and financial strain were uniquely associated with depressive symptoms and the exacerbation of symptoms over time, above and beyond pandemic-related anxiety. Considering the painful dilemma of lockdown versus reopening, with the tradeoff between public health and economic wellbeing, our findings provide evidence that the economic impact of COVID-19 has negative implications for mental health. FUNDING: This study was supported by grants from the National Institute of Mental Health, the US-Israel Binational Science Foundation, Foundation Dora and Kirsh Foundation.

CD44 Deficiency Is Associated with Increased Susceptibility to Stress-Induced Anxiety-like Behavior in Mice.

CD44 is a cell surface adhesion molecule and its principal ligand is hyaluronic acid (HA), a key component of the brain's extracellular matrix. CD44 levels are decreased in the cerebrospinal fluid (CSF) of depressed individuals, and the CD44 gene has been identified in genome wide association study as a possible risk gene in suicidal behavior. In order to define the pathobiological mechanisms by which CD44 may affect behavior, we investigated the role of CD44 using male CD44 knockout (CD44KO) and wild-type mice that underwent chronic mild stress (CMS). Behavior was characterized using the sucrose preference and forced swim tests, open field, novel object recognition, social preference, and the elevated plus maze tests. Gene expression in hippocampus was evaluated using quantitative real-time PCR. Brain monoamines and their metabolites were assessed by high-performance liquid chromatography and serum HA and IL-1ß levels were measured using ELISA and electrochemiluminescence assays. CD44KO mice were more susceptible to stress-induced anxiety-like behavior and displayed increased anhedonia and despair than the wild-type controls. The behavioral phenotype of stressed CD44KO mice was associated with reduced cortical serotonergic and striatal dopaminergic turnover. The hippocampal expression of the receptor for HA-mediated motility (RHAMM) was reduced in the non- stressed CD44KO mice compared with WT mice, in a value similar to that observed in WT mice following exposure to stress. Taken together, our experiments suggest that CD44 plays a key role in stress response in mice.

Psychological autopsy of seventy high school suicides: Combined qualitative/quantitative approach.

OBJECTIVE: Suicide is the leading cause of death among Israeli youths but data on causes are scarce. This study used psychological autopsies of 70 Israeli school students who committed suicide during 2004-2011, attempting to determine the causes. METHODS: Four narratives of the self were identified (qualitative analysis) and compared (quantitative analysis): (1) regressive: functioning and mood deteriorated continuously (45%); (2) tragic: doing well until rapid decline around suicidal crisis (20%); (3) unstable: peaks and crises throughout life (20%); and (4) stable: long lasting state of adverse living circumstances (15%). Functioning, mental disorders, stressful life events and substance abuse were examined. RESULTS: A representative profile of the suicide-completer emerged. Suicidality in the tragic narrative involved shorter crisis, fewer risk factors and less psychopathology than the other narratives, also better general functioning and better school performance. Though decrease in functioning was evident in all groups, in the tragic group it tended to be disregarded. CONCLUSION: This study presents an in-depth analysis of a unique suicide population of high school students. A combined methodology of qualitative and quantitative analyses reveals a distinct subpopulation of suicidal adolescents with little or no overt psychopathology that poses a challenge to suicide prevention strategies.

The CD44 ligand hyaluronic acid is elevated in the cerebrospinal fluid of suicide attempters and is associated with increased blood-brain barrier permeability.

BACKGROUND: The glycosaminoglycan hyaluronic acid (HA) is an important component of the extracellular matrix (ECM) in the brain. CD44 is a cell adhesion molecule that binds to HA in the ECM and is present on astrocytes, microglia and certain neurons. Cell adhesion molecules have been reported to be involved in anxiety and mood disorders. CD44 levels are decreased in the cerebrospinal fluid (CSF) of depressed individuals, and the CD44 gene has been identified in brain GWAS studies as a possible risk gene for suicidal behavior. METHOD: We measured the CSF levels of HA and the soluble CD44 (sCD44) in suicide attempters (n=94) and in healthy controls (n=45) using ELISA and electrochemiluminescence assays. We also investigated other proteins known to interact with CD44, such as osteopontin and the matrix metalloproteinases MMP1, MMP3 and MMP9. RESULTS: The suicide attempters had higher CSF levels of HA (p=.003) and MMP9 (p=.004). The CSF levels of HA correlated with BBB-permeability (rho=0.410, p<.001) and MMP9 correlated with sCD44 levels (rho=0.260, p=.005). LIMITATIONS: Other relevant biological contributors to suicidal behavior is not addressed in parallel to the specific role of CD44-HA signaling. The gender distribution of the patients from whom CSF was analyzed was uneven. CONCLUSIONS: Increased BBB-permeability and HA levels might be a results of increased neuroinflammation and can play a role in the pathobiology of suicidal behavior. The CD44 signaling pathway might be considered a novel target for intervention in mood disorders.

Elevated C-reactive protein levels in schizophrenia inpatients is associated with aggressive behavior.

BACKGROUND: An association between inflammation and behavioral domains of mental disorders is of growing interest. Recent studies reported an association between aggression and inflammation. In this study, we investigated the association between aggressive behavior and inflammatory markers in schizophrenia inpatients. METHODS: Adult schizophrenia inpatients without affective symptoms (n=213) were retrospectively identified and categorized according to their C-reactive protein measurement at admission as either elevated (CRP>1 mg/dL; n=57) or normal (CRP<1 mg/dL; n=156). The following indicators of aggression were compared: PANSS excitement component (PANSS-EC), restraints and suicidal behavior during hospitalization. Univariate comparisons between elevated and normal CRP levels were performed and multivariate analysis was conducted to control for relevant covariates. RESULTS: CRP levels significantly correlated with other laboratory markers indicating increased inflammation including leukocyte count and neutrophil to lymphocyte ratio (r=0.387, P<0.0001 and r=0.356, P<0.0001) respectively. Inpatients with elevated C-reactive protein displayed increased aggressive behavior compared to patients with normal CRP levels (<1 mg/dL). This was manifested by higher rates of restraint during hospitalization (χ(2)=5.22, P=0.031) and increased PANSS-EC score (U=5410.5, P=0.012). Elevated CRP levels were not associated with suicidal behavior. Multivariate analysis revealed that higher PANSS-EC score was associated with elevated CRP after controlling for the covariates age, sex, BMI and smoking. CONCLUSION: This study identified a potential biological correlate (inflammation) of a specific behavioral endophenotype (aggression) in schizophrenia inpatients.

Mesenchymal stem cells induced to secrete neurotrophic factors attenuate quinolinic acid toxicity: a potential therapy for Huntington's disease.

Huntington's disease (HD) is a hereditary, progressive and ultimately fatal neurodegenerative disorder. Excitotoxicity and reduced availability of neurotrophic factors (NTFs) likely play roles in HD pathogenesis. Recently we developed a protocol that induces adult human bone marrow derived mesenchymal stem cells (MSCs) into becoming NTF secreting cells (NTF(+) cells). Striatal transplantation of such cells represents a promising autologous therapeutic approach whereby NTFs are delivered to damaged areas. Here, the efficacy of NTF(+) cells was evaluated using the quinolinic acid (QA) rat model for excitotoxicity. We show that NTF(+) cells transplanted into rat brains after QA injection survive transplantation (19% after 6 weeks), maintain their NTF secreting phenotype and significantly reduce striatal volume changes associated with QA lesions. Moreover, QA-injected rats treated with NTF(+) cells exhibit improved behavior; namely, perform 80% fewer apomorphine induced rotations than PBS-treated QA-injected rats. Importantly, we found that MSCs derived from HD patients can be induced to become NTF(+) cells and exert efficacious effects similarly to NTF(+) cells derived from healthy donors. To our knowledge, this is the first study to take adult bone marrow derived mesenchymal stem cells from patients with an inherited disease, transplant them into an animal model and evidence therapeutic benefit. Using MRI we demonstrate in vivo that PBS-treated QA-injected striatae exhibit increasing T(2) values over time in lesioned regions, whereas T(2) values decrease in equivalent regions of QA-injected rats treated with NTF(+) cells. We conclude that NTF cellular treatment could serve as a novel therapy for managing HD.

Intracerebral adult stem cells transplantation increases brain-derived neurotrophic factor levels and protects against phencyclidine-induced social deficit in mice.

Stem cell-based regenerative therapy is considered a promising cellular therapeutic approach for the patients with incurable brain diseases. Mesenchymal stem cells (MSCs) represent an attractive cell source for regenerative medicine strategies for the treatment of the diseased brain. Previous studies have shown that these cells improve behavioral deficits in animal models of neurological disorders such as Parkinson's and Huntington's diseases. In the current study, we examined the capability of intracerebral human MSCs transplantation (medial pre-frontal cortex) to prevent the social impairment displayed by mice after withdrawal from daily phencyclidine (PCP) administration (10 mg kg(-1) daily for 14 days). Our results show that MSCs transplantation significantly prevented the PCP-induced social deficit, as assessed by the social preference test. In contrast, the PCP-induced social impairment was not modified by daily clozapine treatment. Tissue analysis revealed that the human MSCs survived in the mouse brain throughout the course of the experiment (23 days). Significantly increased cortical brain-derived neurotrophic factor levels were observed in the MSCs-treated group as compared with sham-operated controls. Furthermore, western blot analysis revealed that the ratio of phosphorylated Akt to Akt was significantly elevated in the MSCs-treated mice compared with the sham controls. Our results demonstrate that intracerebral transplantation of MSCs is beneficial in attenuating the social deficits induced by sub-chronic PCP administration. We suggest a novel therapeutic approach for the treatment of schizophrenia-like negative symptoms in animal models of the disorder.

Regenerative effect of neural-induced human mesenchymal stromal cells in rat models of Parkinson's disease.

BACKGROUND: Human bone marrow multipotent mesenchymal stromal cells (hMSC), because of their capacity of multipotency, may provide an unlimited cell source for cell replacement therapy. The purpose of this study was to assess the developmental potential of hMSC to replace the midbrain dopamine neurons selectively lost in Parkinson's disease. METHODS: Cells were isolated and characterized, then induced to differentiate toward the neural lineage. In vitro analysis of neural differentiation was achieved using various methods to evaluate the expression of neural and dopaminergic genes and proteins. Neural-induced cells were then transplanted into the striata of hemi-Parkinsonian rats; animals were tested for rotational behavior and, after killing, immunohistochemistry was performed. RESULTS: Following differentiation, cells displayed neuronal morphology and were found to express neural genes and proteins. Furthermore, some of the cells exhibited gene and protein profiles typical of dopaminergic precursors. Finally, transplantation of neural-induced cells into the striatum of hemi-Parkinsonian rats resulted in improvement of their behavioral deficits, as determined by apomorphine-induced rotational behavior. The transplanted induced cells proved to be of superior benefit compared with the transplantation of naive hMSC. Immunohistochemical analysis of grafted brains revealed that abundant induced cells survived the grafts and some displayed dopaminergic traits. DISCUSSION: Our results demonstrate that induced neural hMSC may serve as a new cell source for the treatment of neurodegenerative diseases and have potential for broad application. These results encourage further developments of the possible use of hMSC in the treatment of Parkinson's disease.