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Abstract: Although rapid cycling (RC), a course specifier of bipolar I or II disorder, is particularly common among bipolar II patients compared with bipolar I patients, the pathophysiological lines of evidence regarding bipolar II with RC are still limited. In this preliminary study with a cross-sectional design, we examined the regional gray matter (GM) volume in 14 bipolar II patients with RC, 17 patients without RC and 84 healthy controls by whole-brain and region-of-interest (ROI) analysis methods, using magnetic resonance imaging with voxel-based morphometry. Whole-brain analysis in this study revealed that the bipolar II patients with RC showed GM volume reductions in the bilateral hemispheres of the medial orbital prefrontal cortex, ventromedial prefrontal cortex, anterior cingulate, insula and parahippocampus, in the left hemisphere of the inferior temporal cortex and cerebellum, and in the brainstem, compared with the healthy controls. Moreover, ROI analysis focusing on the ventral prefrontal cortex, i.e., Brodmann areas 10, 11 and 47, revealed that the bipolar II patients with RC showed GM volume reduction in the ventromedial prefrontal cortex, compared with the patients without RC. The findings of our pilot study suggest that the ventromedial prefrontal cortex is associated with the generation of RC in bipolar II disorder. [Copyright &y& Elsevier]

Abstract: Previous epidemiologic studies using the parental bonding instrument (PBI), a self-report scale to rate attitudes of parents during the first 16years, have suggested that a lower parental care score or higher parental overprotection score could lead to an increased risk of several psychiatric disorders, including schizophrenia and mood disorder. However, neuroimaging studies of an association between PBI scores and brain developmental abnormalities are still limited. In this region-of-interest analysis study using a cross-sectional design, we examined 50 normal young adults, in terms of relationships of parental bonding styles during the first 16years measured by PBI with regional gray matter (GM) volume in the dorsolateral prefrontal cortex (DLPFC). Our study showed that paternal care score positively correlated with the GM volume in the left DLPFC, and paternal and maternal overprotection score negatively correlated with the GM volume in the left DLPFC. In conclusion, our results suggest that in normal young adults, lower paternal care and higher parental overprotection scores correlated with the GM volume reduction in the DLPFC [Copyright &y& Elsevier]

Summary: Anxiety has been shown to be associated with cardiovascular disease. Atherosclerosis is responsible for the vast majority of cardiovascular events. Recent evidence is accumulating to show that insulin resistance (IR) plays a central role in determining the clinical manifestations of established atherosclerotic lesions. The current preliminary study aimed to investigate the associations between trait anxiety, IR, and atherosclerotic progression in healthy elderly subjects with normal fasting glucose and without metabolic syndrome. Thirty-five healthy elderly subjects (19 males and 16 females, mean age 64.5±4.7 years) were enrolled in this study. Trait anxiety was measured using a questionnaire corresponding to the trait anxiety scale taken from the State and Trait Anxiety Inventory. The homeostasis model assessment (HOMA-R) and plasma leptin-to-adiponectin ratio (L/A ratio), which are convenient IR indexes calculated from fasting blood sampling, were examined. As measurements of atherosclerotic progression, we performed two ultrasound methods, namely brachial artery flow-mediated dilation (FMD), an endothelial function assessment quantitatively reflecting the endothelium-dependent vasodilation responses following hyperemia, and measurement of carotid intima-media thickness (IMT). The severity of trait anxiety was positively associated with HOMA-R and L/A ratio, and negatively associated with the percent change of brachial artery FMD (%FMD). HOMA-R and L/A ratio were positively associated with carotid IMT, and L/A ratio was negatively associated with %FMD. These data showed the associations between trait anxiety, IR indexes and endothelial dysfunction or atherosclerotic progression. This pilot study, with a cross-sectional design, supports the promising role of IR for clarifying the pathophysiological mechanism by which anxiety contributes to an increasing risk of atherosclerosis. [Copyright &y& Elsevier]

Abstract: Adiponectin is an adipocyte-specific secretory protein that circulates in serum as three oligomeric complexes known as the high, medium and low molecular weight form (HMW, MMW and LMW). HMW adiponectin has been suggested to be a better predictor of metabolic variables, and it was recently reported that the ratio of HMW to total adiponectin or to LMW, not the absolute amount of plasma adiponectin, might be crucial in determining insulin sensitivity. Insulin resistance (IR) is considered to be a primary component of vascular risk factors. Although the association of depression with atherosclerotic vascular diseases has been well documented, the contribution of IR to the evolution and progression of depression-associated vascular morbidity and mortality remains unknown. The current preliminary study showed that the ratio of HMW to total adiponectin or to LMW, not the absolute amount of plasma adiponectin, was negatively associated with depression severity in healthy elderly subjects without metabolic syndrome. This pilot study supports a promising role of adiponectin multimer distribution for clarifying the pathophysiological mechanism by which depression is associated with increased risk for IR, leading to cardiovascular disease, metabolic syndrome or type 2 diabetes. [Copyright &y& Elsevier]

Abstract: Negative psychological characteristics have been recognized as independent risk factors of cardiovascular disease (CVD). The purpose of this study was to evaluate the influence of depression and anxiety on cardiac autonomic function and endothelial function in healthy elderly subjects. Forty-six healthy elderly volunteers (mean age 60.8 years) were enrolled in this study. Cardiac autonomic function was assessed by spectral analysis of heart rate variability (HRV) with the head-up tilt test. Brachial artery endothelium-dependent flow-mediated dilation (FMD) was measured using high-resolution ultrasound. A significant positive correlation was observed between the State and Trait Anxiety Inventory (STAI)-trait score as a parameter of anxiety and HRV sympathetic modulation in the supine position (baseline), and a significant negative correlation between this score and the head-up-induced HRV sympathetic response from the baseline. The STAI-trait score also showed a significant negative correlation with the percent change of FMD (%FMD). Analysis using structural equation modeling showed that higher trait anxiety reduced %FMD via abnormalities of sympathetic activity. On the other hand, psychometric parameters of depression were not associated with any HRV component or %FMD. These results suggest that there are specific interactions among higher trait anxiety, abnormalities of sympathetic activity, and endothelial dysfunction. This finding may be useful in clarifying the pathophysiological mechanism by which anxiety is associated with increased risks for atherosclerosis and CVD. [Copyright &y& Elsevier]

Abstract: Adiponectin, an adipose tissue-specific plasma protein, is involved in insulin sensitization and has anti-atherosclerotic properties, whereas tumor necrosis factor-α (TNF-α), a pro-inflammatory protein, plays important roles in inflammatory endothelial injury and atherosclerotic changes. It has been reported that adiponectin and TNF-α inhibit each other''s expression and production in adipocytes. Several in vitro studies indicated that antidepressant medications decreased the production of pro-inflammatory cytokines including TNF-α, but the effect of antidepressants on the expression of adiponectin is still unknown. We examined the plasma levels of TNF-α and adiponectin in patients with remitted depression receiving maintenance antidepressant therapy for longer than half a year, and compared the levels with those in healthy controls. The plasma levels of TNF-α and adiponectin in the remitted depression group were significantly lower and higher than those in the control group, respectively. This preliminary cross-sectional study suggests the possibility that maintenance antidepressant therapy may have anti-inflammatory effects and prevent the development of atherosclerosis. [Copyright &y& Elsevier]

Background: Recent accumulating lines of evidence reveal that leptin is associated with synaptic plasticity and neuroprotective activity in the brain. Methods: In this preliminary study with a cross-sectional design, we examined the relationship between plasma leptin level and total or regional gray matter (GM) volume in 34 elderly subjects (mean age 64.5 years) with normal fasting glucose level and without dementia and metabolic syndrome by voxel-based morphometry of magnetic resonance imaging scans. Results: Plasma leptin level showed no significant correlation with total GM volume but showed a significantly positive correlation with GM volumes in the right hippocampus, left parahippocampus, and right cerebellum with adjustments for age, gender, body mass index (BMI), and waist-to-hip ratio (W/H). Also, after adjustments for age, gender, BMI, W/H, and intracranial volume, plasma leptin level significantly positively correlated with GM volumes in the right hippocampus and bilateral cerebella but not with that in the left parahippocampus. Conclusions: The results of this pilot study would be beneficial for our understanding of the neuroprotective effects of leptin on human brain aging. [Copyright &y& Elsevier]

Major depressive disorder (MDD) and bipolar disorder (BD) patients show speech characteristics that vary greatly according to mood state. In a previous study, we found impaired temporal and right inferior frontal gyrus (IFG) activation in schizophrenia during face-to-face conversation; no study had, however, previously investigated mood disorders during face-to-face conversation. Here, we investigated frontal and temporal lobe activation during conversation in patients with MDD and BD. Frontal and temporal lobe activation was measured using near-infrared spectroscopy (NIRS) in 29 patients with MDD, 31 patients with BD, and 31 normal controls (NC). We compared continuous activation and rapid change of activation with talk/listen phase changes during the conversation and analyzed the correlation between these indices and clinical variables. Both the MDD and BD groups showed decreased continuous activation in the left dorsolateral prefrontal (DLPFC) and left frontopolar cortices (FPCs); they also showed decreased rapid change in bilateral FPC activation. In the MDD group, the rapid change of activation was positively correlated with Global Assessment of Functioning (GAF) scores. In the BD group, continuous activation was negatively correlated with age of onset. These results indicate that frontal activation during conversation decreases in both MDD and BD. However, both continuous activation and rapid change may reflect the pathophysiological character of MDD and BD; in particular, the reduced amount of rapid change in the right FPC may be related to impaired adaptive ability in MDD. [ABSTRACT FROM AUTHOR]

Abstract: Schizophrenia (SC) is marked by poor social-role performance and social-skill deficits that are well reflected in daily conversation. Although the mechanism underlying these impairments has been investigated by functional neuroimaging, technical limitations have prevented the investigation of brain activation during conversation in typical clinical situations. To fill this research gap, this study investigated and compared frontal and temporal lobe activation in patients with SC during face-to-face conversation. Frontal and temporal lobe activation in 29 patients and 31 normal controls (NC) (n = 60) were measured during 180-s conversation periods by using near-infrared spectroscopy (NIRS). The grand average values of oxyhemoglobin concentration ([oxy-Hb]) changes during task performance were analyzed to determine their correlation with clinical variables and Positive and Negative Syndrome Scale (PANSS) subscores. Compared to NCs, patients with SC exhibited decreased performance in the conversation task and decreased activation in both the temporal lobes and the right inferior frontal gyrus (IFG) during task performance, as indicated by the grand average of [oxy-Hb] changes. The decreased activation in the left temporal lobe was negatively correlated with the PANSS disorganization and negative symptoms subscores and that in the right IFG was negatively correlated with illness duration, PANSS disorganization, and negative symptom subscores. These findings indicate that brain dysfunction in SC during conversation is related to functional deficits in both the temporal lobes and the right IFG and manifests primarily in the form of disorganized thinking and negative symptomatology. [Copyright &y& Elsevier]

Abstract: Near-infrared spectroscopy (NIRS) is a functional brain imaging technique for monitoring brain activation in a natural setting using near-infrared light, and hence, is considered to have some advantages for studies of brain function during social interactions such as face-to-face conversation compared with functional magnetic resonance imaging and positron emission tomography, which have methodological constraints for studying brain mechanisms underlying social interactions: subjects have to lie down on a bed in a small gantry during examination. The purpose of this study was to validate the possible use of NIRS as a functional brain imaging technique for studying social interactions in a natural setting; therefore, we investigated frontal and temporal lobe activation during face-to-face conversation in healthy subjects in the sitting position. The frontal and superior temporal regions were activated during face-to-face conversation, with higher activity in the speaking segments than in the mute segments during conversation particularly in frontopolar NIRS channels. The magnitude of frontopolar activity negatively correlated with the cooperativeness score of the subjects assessed using the temperament and character inventory. These results demonstrated the successful monitoring of brain function during realistic social interactions using NIRS and interindividual differences in frontopolar activity during conversation in relation to the cooperativeness of an individual. [Copyright &y& Elsevier]

Abstract: Multifractal analysis provides a precise quantitative description of the structural complexity of white matter (WM) on magnetic resonance imaging (MRI). To test this new technique as an aid to elucidating the pathology of schizophrenia, we examined a multifractal dimension (i.e. Δα) of WM in schizophrenia patients and their relations to clinical variables. We examined 16 patients with schizophrenia and 16 controls matched for age, sex and handedness. Delta α value of WM in the prefrontal and frontoparietal lobes and the corpus callosum (genu and splenium) on T2-weighted MRI was calculated. Delta α was not significantly different between groups in either region of interest. However, group-by-side interaction for Δα was found in the frontoparietal WM; post-hoc analysis revealed normal left dominant asymmetry in Δα for frontoparietal WM in control subjects, which was absent in schizophrenia patients. Furthermore, the patients with schizophrenia had a lower asymmetry coefficient ([R − L]/[R + L]) for Δα in frontoparietal WM. Relations to clinical symptoms from the Positive and Negative Syndrome Scale, Δα in corpus callosum, and the asymmetry coefficient in prefrontal WM were correlated with negative and general psychopathology symptom scores. Our results support the left-sided dysfunction hypothesis of schizophrenia and its relation to schizophrenic symptoms. Multifractal analysis reveals abnormal patterns of WM structures in schizophrenia that could be implicated in the disorder''s etiology. [Copyright &y& Elsevier]