The structure of schizotypal personality traits: a cross-national study.

BACKGROUND: Schizotypal traits are considered a phenotypic-indicator of schizotypy, a latent personality organization reflecting a putative liability for psychosis. To date, no previous study has examined the comparability of factorial structures across samples originating from different countries and cultures. The main goal was to evaluate the factorial structure and reliability of the Schizotypal Personality Questionnaire (SPQ) scores by amalgamating data from studies conducted in 12 countries and across 21 sites. METHOD: The overall sample consisted of 27 001 participants (37.5% males, n = 4251 drawn from the general population). The mean age was 22.12 years (s.d. = 6.28, range 16-55 years). The SPQ was used. Confirmatory factor analysis (CFA) and Multilevel CFA (ML-CFA) were used to evaluate the factor structure underlying the SPQ scores. RESULTS: At the SPQ item level, the nine factor and second-order factor models showed adequate goodness-of-fit. At the SPQ subscale level, three- and four-factor models displayed better goodness-of-fit indices than other CFA models. ML-CFA showed that the intraclass correlation coefficients values were lower than 0.106. The three-factor model showed adequate goodness of fit indices in multilevel analysis. The ordinal α coefficients were high, ranging from 0.73 to 0.94 across individual samples, and from 0.84 to 0.91 for the combined sample. CONCLUSIONS: The results are consistent with the conceptual notion that schizotypal personality is a multifaceted construct and support the validity and utility of SPQ in cross-cultural research. We discuss theoretical and clinical implications of our results for diagnostic systems, psychosis models and cross-national mental health strategies.

Protocol for the prediction, interpretation, and mutation evaluation of post-translational modification using MIND-S.

Post-translational modifications (PTMs) serve as key regulatory mechanisms in various cellular processes; altered PTMs can potentially lead to human diseases. We present a protocol for using MIND-S (multi-label interpretable deep-learning approach for PTM prediction-structure version), to study PTMs. This protocol consists of step-by-step guide and includes three key applications of MIND-S: PTM predictions based on protein sequences, important amino acids identification, and elucidation of altered PTM landscape resulting from molecular mutations. For complete details on the use and execution of this protocol, please refer to Yan et al (2023).1.

Sex differences in orbitofrontal gray as a partial explanation for sex differences in antisocial personality.

Attention is increasingly being given to understanding sex difference in psychopathology to better understand the etiology of disorders. This study tests the hypothesis that sex differences in ventral and middle frontal gray volume contribute to sex differences in antisocial personality disorder (APD) and crime. Participants were recruited from temporary employment agencies, consisting of normal controls, substance/alcohol-dependent controls, axis I/II psychiatric controls and individuals with APD. An independent sample of female volunteers was also recruited. Magnetic resonance imaging volumes of superior frontal, middle frontal, inferior frontal, orbital frontal and rectal gyral frontal gray matter, and dimensional scores of APD and criminal behavior were assessed. APD males when compared with male controls showed an 8.7% reduction in orbitofrontal gray volume, a 17.3% reduction in middle frontal gray and a 16.1% reduction in right rectal gray. Reduced middle and orbitofrontal volumes were significantly associated with increased APD symptoms and criminal offending in both males and females. Males as a whole had reduced orbitofrontal and middle frontal gray volume when compared with females, and controlling for these brain differences reduced the gender difference in the antisocial personality/behavior by 77.3%. Findings were not a function of psychiatric comorbidity, psychosocial risk factors, head injury or trauma exposure. Findings implicate structural differences in the ventral and middle frontal gray as both a risk factor for APD and as a partial explanation for sex differences in APD.

Psychopathic personality in children: genetic and environmental contributions.

BACKGROUND: The current study investigates whether the underlying factor structure of psychopathic personality traits found in adults is similar to that in children and what the extent of the genetic and environmental influences are on these psychopathic traits. METHOD: Psychopathic personality traits were assessed in a community sample of 1219 twins and triplets (age 9-10 years) through caregiver reports of each child's behavior using the Child Psychopathy Scale (CPS). RESULTS: Confirmatory factor analyses revealed an optimal two-factor solution (callous/disinhibited and manipulative/deceitful) to the CPS subscales. Bivariate genetic modeling of the two computed factor scores revealed significant genetic as well as unique environmental influences on psychopathic personality traits in both boys and girls, with heritability estimates of 0.64 and 0.46, respectively, in boys and 0.49 and 0.58, respectively, in girls. No shared environmental influences on psychopathic personality traits were found. CONCLUSIONS: The relationship between the two factors was mediated by both genetic and unique environmental factors common to both traits.

Early maternal and paternal bonding, childhood physical abuse and adult psychopathic personality.

BACKGROUND: A significant gap in the literature on risk factors for psychopathy is the relative lack of research on parental bonding.MethodThis study examines the cross-sectional relationship between maternal and paternal bonding, childhood physical abuse and psychopathic personality at age 28 years in a community sample of 333 males and females. It also assesses prospectively whether children separated from their parents in the first 3 years of life are more likely to have a psychopathic-like personality 25 years later. RESULTS: Hierarchical regression analyses indicated that: (1) poor parental bonding (lack of maternal care and low paternal overprotection) and childhood physical abuse were both associated with a psychopathic personality; (2) parental bonding was significantly associated with psychopathic personality after taking into account sex, social adversity, ethnicity and abuse; (3) those separated from parents in the first 3 years of life were particularly characterized by low parental bonding and a psychopathic personality in adulthood; and (4) the deviant behavior factor of psychopathy was more related to lack of maternal care whereas the emotional detachment factor was related to both lack of maternal care and paternal overprotection. CONCLUSIONS: Findings draw attention to the importance of different components of early bonding in relation to adult psychopathy, and may have potential implications for early intervention and prevention of psychopathy.

Partial divergence of cytokine mRNA expression in bronchial tissues compared to bronchoalveolar lavage cells in horses with recurrent airway obstruction.

The aim of this study was to investigate mRNA levels of cytokines in bronchial epithelium in horses with recurrent airway obstruction (RAO) during acute crisis and remission. Additionally, cytokine mRNA levels in endobronchial biopsies and bronchoalveolar lavage (BAL) cells were compared. Seven RAO horses were examined while in respiratory crisis following provocation and again while in remission after 2 months on pasture, during which time six healthy horses on pasture were also examined. Quantitative real-time PCR (RT-PCR) was used to assess mRNA expression for cytokines IL-5, IL-6, IL-8, IL-10, IL-17 and transforming growth factor beta1 (TGF-beta1) in endobronchial biopsies and bronchoalveolar lavage. Expression of IL-8 mRNA was significantly upregulated during crisis in both endobronchial biopsies and BAL cells (p=0.036), while there was a similar trend for upregulation of IL-10 mRNA only in BAL cells that approached significance (p=0.059). Moreover, during crisis the expression of IL-8 mRNA in BAL cells was positively correlated to relative IL-6 mRNA expression (r(s)=0.971, p=0.001) and bronchial epithelial expression of IL-10 and TGF-beta1 mRNA were positively correlated (r(s)=0.943, p=0.005). In comparing the relationship of mRNA expression in BAL to biopsy in individual RAO horses, there was a positive correlation with IL-6 to IL-8 mRNA expression in BAL during respiratory crisis (r(s)=0.971, p=0.001) that also correlated positively with IL-8 expression in biopsies on pasture (r(s)=0.986, p<0.0001 for both). Regarding RAO horses at pasture versus controls neither the cytokine mRNA levels in endobronchial biopsy nor in BAL cells differed significantly. These results further support previous findings that IL-8 mRNA in both BAL cells and bronchial epithelium is upregulated in RAO horses during crisis. However, apart from IL-8, it appears that expression of other cytokines, including IL-5, IL-6, IL-10, IL-17 and TGF-beta1 in bronchial epithelium does not necessarily mirror cytokine expression in BAL cells in individual horses with RAO. Accordingly, examination of markers of inflammation in endobronchial tissue provides complementary but not necessarily identical information to that obtained in BAL cells. Given the potential for repeated sampling over time bronchial biopsy can serve as an invaluable additional tool for investigation of time-dependent changes in inflammatory process in this animal model of asthma.

Clinical alterations and mRNA levels of IL-4 and IL-5 in bronchoalveolar cells of horses with transient pulmonary eosinophilia.

The aim of this study was to assess clinical signs and altered pulmonary cell expression of cytokines related to eosinophil kinetics in horses with pulmonary eosinophilia. Pulmonary eosinophilia was detected by bronchoalveolar lavage (BAL) in a group of standardbreds in training. Horses had detailed clinical examination, bronchoscopy, endobronchial biopsy and BAL on three occasions at approximately 6 month intervals. During the second sampling period BAL eosinophils were significantly elevated (p>0.010), with five horses having from 5% to 37% eosinophils in BAL. Neither detailed clinical examination parameters nor gene expression of IL-4 and IL-5 mRNA (real-time-PCR) were associated with BAL eosinophilia. Pulmonary eosinophilia abated without treatment apart from deworming. It appears that pronounced lung eosinophilia in horses can be transient, abate without specific treatment, and in this instance, lack correlation to upregulation of expression of either IL-4 or IL-5.

Impairment of cardiac function and energetics in experimental renal failure.

Cardiac function and energetics in experimental renal failure in the rat (5/6 nephrectomy) have been investigated by means of an isolated perfused working heart preparation and an isometric Langendorff preparation using 31P nuclear magnetic resonance (31P NMR). 4 wk after nephrectomy cardiac output of isolated hearts perfused with Krebs-Henseleit buffer was significantly lower (P < 0.0001) at all levels of preload and afterload in the renal failure groups than in the pair-fed sham operated control group. In control hearts, cardiac output increased with increases in perfusate calcium from 0.73 to 5.61 mmol/liter whereas uremic hearts failed in high calcium perfusate. Collection of 31P NMR spectra from hearts of renal failure and control animals during 30 min normoxic Langendorff perfusion showed that basal phosphocreatine was reduced by 32% to 4.7 mumol/g wet wt (P < 0.01) and the phosphocreatine to ATP ratio was reduced by 32% (P < 0.01) in uremic hearts. During low flow ischemia, there was a substantial decrease in phosphocreatine in the uremic hearts and an accompanying marked increase in release of inosine into the coronary effluent (14.9 vs 6.1 microM, P < 0.01). We conclude that cardiac function is impaired in experimental renal failure, in association with abnormal cardiac energetics and increased susceptibility to ischemic damage. Disordered myocardial calcium utilization may contribute to these derangements.

Energy metabolism in reperfused heart muscle: metabolic correlates to return of function.

An important question in energy metabolism of the reperfused, previously ischemic myocardium is whether the return of a normal tissue adenosine triphosphate (ATP) content is a prerequisite for normal rates of oxygen consumption (that is, ATP turnover) and cardiac function. To study this problem, isolated working rat hearts were perfused with bicarbonate saline solution containing glucose (10 mM) at near physiologic work load. After 20 minutes, hearts were made totally ischemic by clamping the aortic and atrial lines for 5, 10 or 20 minutes and then were reperfused for another 10 minutes. Heart rate, aortic pressure, cardiac output and myocardial oxygen consumption were measured continuously. Adenine nucleotides, phosphocreatine, glycogen and the products of glycolysis were determined in freeze-clamped tissue extracts. Functional recovery was assessed by return of aortic pressure and oxygen consumption to preischemic values. Time required for return of function after reperfusion was 90 seconds after 5 minutes and 124 seconds after 10 minutes of ischemia. No recovery was observed after 20 minutes of ischemia. Tissue ATP content decreased significantly at the end of 5 (-38%) and 10 (-56%) minutes of ischemia and did not increase significantly at return of aortic pressure and oxygen consumption to preischemic values. Glycogen stores decreased by more than 50% at the end of 10 minutes of ischemia and did not normalize on recovery. In contrast to ATP or glycogen, the phosphocreatine content decreased to even lower levels at the end of ischemia, but returned to levels higher than the control level after recovery from 5 to 10 minutes of ischemia in association with return of function.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationships between central and autonomic measures of arousal at age 15 years and criminality at age 24 years.

Previous studies have indicated that criminality is in part genetically determined, but it is not clear how this predisposition manifests itself at a biological level. This prospective study tests the hypothesis that a psychophysiological predisposition to criminality partly manifests itself through autonomic and central nervous system underarousal. Psychophysiological measures, taken at the age of 15 years, were related to criminality status that was assessed at the age of 24 years. Criminals had a significantly lower resting heart rate, skin conductance activity, and more slow-frequency electroencephalographic activity than noncriminals. Differences were not mediated by social, demographic, and academic factors. These results constitute the first clear evidence that implicates underarousal in all three response systems (electrodermal, cardiovascular, and cortical) in the development of criminality. Although arousal variables correctly classified 74.7% of all subjects, psychophysiological factors alone cannot fully account for criminal behavior and do not negate the potential role of social variables in predicting criminal behavior.

Birth complications combined with early maternal rejection at age 1 year predispose to violent crime at age 18 years.

BACKGROUND: This study tests the bisocial interaction hypothesis that birth complications when combined with early maternal rejection of the infant predispose to adult violent crime. METHODS: This hypothesis was tested using a cohort of 4269 consecutive live male births on whom measures of birth complications (age 0), early maternal rejection (age 1 year), and violent crime (age 18 years) were collected. RESULTS: A significant interaction (P < .0001) between birth complications and early maternal rejection indicated that those who suffered both birth complications and early child rejection were most likely to become violent offenders in adulthood. While only 4.5% of the subjects had both risk factors, this small group accounted for 18% of all violent crimes. The effect was specific to violence and was not observed for nonviolent criminal offending. CONCLUSIONS: To our knowledge, this is the first study to show that birth complications in combination with early child rejection predispose to violent crime. The findings illustrate the critical importance of integrating biological with social measures to fully understand how violence develops and also suggest that prenatal, perinatal, and early postnatal health care interventions could significantly reduce violence.

Reduced prefrontal gray matter volume and reduced autonomic activity in antisocial personality disorder.

BACKGROUND: Major damage to gray and white matter in the prefrontal cortex and autonomic deficits have been found to result in pseudopsychopathic personality in patients with neurological disorders, but it is not known whether people with antisocial personality disorder (APD) in the community who do not have discernable brain trauma also have subtle prefrontal deficits. METHODS: Prefrontal gray and white matter volumes were assessed using structural magnetic resonance imaging in 21 community volunteers with APD (APD group) and in 2 control groups, comprising 34 healthy subjects (control group), 26 subjects with substance dependence (substance-dependent group), and 21 psychiatric controls. Autonomic activity (skin conductance and heart rate) was also assessed during a social stressor in which participants gave a videotaped speech on their faults. RESULTS: The APD group showed an 11.0% reduction in prefrontal gray matter volume in the absence of ostensible brain lesions and reduced autonomic activity during the stressor. These deficits predicted group membership independent of psychosocial risk factors. CONCLUSIONS: To our knowledge, these findings provide the first evidence for a structural brain deficit in APD. This prefrontal structural deficit may underlie the low arousal, poor fear conditioning, lack of conscience, and decision-making deficits that have been found to characterize antisocial, psychopathic behavior.

High rates of violence, crime, academic problems, and behavioral problems in males with both early neuromotor deficits and unstable family environments.

BACKGROUND: It is commonly assumed that individuals with both biological and psychosocial deficits are more likely to become criminal, but there is surprisingly little empirical support for this assumption. We test the hypothesis that a group with biosocial risk factors are more likely to develop behavioral and academic problems in adolescence and violent criminal offending in adult-hood compared with groups with only biological or only social risk factors. METHODS: Hypotheses were tested on a sample of 397 male subjects, using obstetric and early neuromotor measures collected in the first year of life; family, social, demographic, and behavioral measures at age 17 to 19 years; and criminal data at 20 to 22 years of age. RESULTS: Cluster analysis of the risk factors indicated a group with obstetric risk factors only, a group with poverty risk factors only, and a biosocial group with both early neuromotor deficits and unstable family environments. The biosocial group had more than double the adult violence, theft, and total crime rates of the other 2 groups and had significantly more behavioral and academic problems in adolescence. CONCLUSIONS: When early neuromotor deficits and negative family factors cluster together, individuals are particularly likely to become criminal and violent compared with those with only poverty or only obstetric risk factors. Because this biosocial group accounted for 70.2% of all crimes committed in the entire sample, early interventions that tackle these deficits might significantly reduce violence.

Structural and functional characteristics of the corpus callosum in schizophrenics, psychiatric controls, and normal controls. A magnetic resonance imaging and neuropsychological evaluation.

In 1986 Nasrallah and colleagues found that increased thickness of the corpus callosum may be specific to right-handed female schizophrenics. Male and female right-handed schizophrenics were compared with normal and psychiatric controls of comparable age, sex, education, and social class on measures of callosal thickness from a midsagittal magnetic resonance imaging cut and neuropsychological tests of interhemispheric transfer. The sex difference in anterior and posterior callosal thickness in normal controls was reversed in schizophrenics, with the corpus callosum being thicker in female schizophrenics and thinner in male schizophrenics. Similar findings were also observed in the psychiatric control group. These structural differences were not paralleled by evidence of impaired interhemispheric transfer on neuropsychological tasks. These results support the finding of sex-dependent callosal abnormalities in schizophrenia but indicate that these abnormalities may not be specific to this illness.

Fearlessness, stimulation-seeking, and large body size at age 3 years as early predispositions to childhood aggression at age 11 years.

BACKGROUND: Previous cross-sectional research in Western societies has linked adolescent stimulation-seeking, fearlessness, and body size to antisocial behavior. However, it is unclear how early in life these factors exert their influence, and nothing is known about their specificity to aggressive behavior per se. This study tests the hypotheses that stimulation-seeking, fearlessness, and increased body size at age 3 years predict aggression at age 11 years. METHODS: Behavioral measures of stimulation-seeking and fearlessness, together with height and weight, were measured at age 3 years and related to ratings of aggression at age 11 years in 1130 male and female Indian and Creole children from the island of Mauritius. RESULTS: Aggressive children at age 11 years were characterized by increased measures of stimulation-seeking, fearlessness, height, and weight at age 3 years. Stimulation-seeking and height were independently related to aggression, whereas the fearlessness-aggression relationship was mediated by height. Large body size at age 3 years but not 11 years was related to increased aggression at age 11 years, indicating a critical period in development for the influence of body size on aggression. CONCLUSIONS: Results (1) implicate large body size, stimulation-seeking, and fearlessness in the development of childhood aggression; (2) suggest that there may be a critical period in development in which biological processes influence later aggression; and (3) highlight the importance of early processes in the etiology of aggression.

Improved methods for structural studies of proteins using nuclear magnetic resonance spectroscopy.

The past few years have seen the development of three- and four-dimensional heteronuclear nuclear magnetic resonance methods. Increased sophistication in labelling strategies, use of pulse-field gradients and the application of these methods at higher magnetic fields has, in combination with improved software, allowed studies of the structure, interactions and dynamics of significantly larger proteins (now up to approximately 270 amino acid residues).

The effects of prolonged beta-adrenoceptor blockade on heart weight and cardiac intracellular potentials in rabbits.

Estimates were made in vivo in rabbits of the relative beta-receptor blocking potency and duration of action of propranolol and practolol. In further experiments groups of litter mates were injected twice daily with approximately equi-active amounts of propranolol or practolol, or with saline, for several weeks. The heart weights of the treated animals were significantly lower than those of the controls, the water contents were higher, and the dry weight differences were highly significant; -16.8% after 2 mg/kg bd propranolol for six weeks and -33.8% after 10 mg/kg practolol. (The treated animals grew less rapidly than the controls; when corrected for body weight these figures were -11.9% and -20.4%, respectively.) In the practolol group, but not the propranolol group, the duration of the atrial intracellular potentials was prolonged. There was no evidence that the prolonged treatment with either drug had a negative inotropic effect, or reduced positive inotropic responses to isoprenaline.

Neural mediator of the schizotypy-antisocial behavior relationship.

Prior studies have established that schizotypal personality traits (schizotypy) were associated with antisocial behavior (crime), but it is unclear what neural factors mediate this relationship. This study assessed the mediating effect that sub-regional prefrontal gray, specifically the orbitofrontal gray matter volume, has on the schizotypy-antisocial behavior relationship. Five prefrontal sub-regional (superior, middle, inferior, orbitofrontal and rectal gyral) gray matter volumes were assessed using structural magnetic resonance imaging in 90 adults from the community, together with schizotypy and antisocial behavior. Among all five prefrontal sub-regions, the orbitofrontal cortex (OFC) was the major region-of-interest in the present study. Mediation analyses showed that orbitofrontal gray fully mediated the association between schizotypy and antisocial behavior. After having controlled the sex, age, socio-economic statuses, whole brain volumes and substance abuse/dependence of test subjects, the orbitofrontal gray still significantly mediated the effect of schizotypy on antisocial behavior by 53.5%. These findings are the first that document a neural mediator of the schizotypy-antisocial behavior relationship. Findings also suggest that functions subserved by the OFC, including impulse control and inhibition, emotion processing and decision-making, may contribute to the above comorbidity.