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Background Clozapine (CLZ) is most specific suitable treatment of refractory schizophrenia; however, it might lead a variety of adverse reactions that cause drug non-compliance. Although it is necessary to conduct therapeutic drug monitoring through measuring psychoactive drug plasma concentration measurement, it has limitation in that it takes several days and it is invasive. Previous studies have suggested that the heart rate variability (HRV) might serves as non-invasive and fast marker to monitoring pharmacodynamic intra-individual effects of the drug. This study aimed to investigate whether and which HRV parameters predict CLZ plasma concentration in natural clinical and polypharmacy conditions. Methods Total 85 patients (Male = 49 and Female = 36; Mean age = 35.95±9.45 years old; Mean CLZ intake = 6.21±4.86 years old) with schizophrenia who had received clozapine without the change of clozapine dosage at least 7 days before blood sampling for TDM and electrocardiogram (ECG) measuring participated in this study. ECG data were collected during resting-state. Linear and nonlinear HRV analysis were ran. Results Based on significant results from correlational analysis with the CLZ plasma level, univerate generalized linear regression model (GLM) with gamma distribution were conducted with adjusting the effect of age and sex. As results, for linear parameters of HRV, pNN5, pNN10, and VLF were inversely associated with the CLZ plasma level (Ps Discussion HRV, especially for crossover, could be a candidate of a surrogate marker of CLZ concentration for drug-monitoring in patients with treatment-resistant schizophrenia in a polypharmacy condition. Findings of this study would helpful to make a clinical decision of CLZ dosage adjustment on site without the delay.

Intracellular Vitamin C (VC) is maintained at high levels in the developing brain by the activity of sodium-dependent VC transporter 2 (Svct2), suggesting specific VC functions in brain development. A role of VC as a cofactor for Fe(II)-2-oxoglutarate-dependent dioxygenases has recently been suggested. We show that VC supplementation in neural stem cell cultures derived from embryonic midbrains greatly enhanced differentiation toward midbrain-type dopamine (mDA) neurons, the neuronal subtype associated with Parkinson's disease. VC induced gain of 5-hydroxymethylcytosine (5hmC) and loss of H3K27m3 in DA phenotype gene promoters, which are catalyzed by Tet1 and Jmjd3, respectively. Consequently, VC enhanced DA phenotype gene transcriptions in the progenitors by Nurr1, a transcription factor critical for mDA neuron development, to be more accessible to the gene promoters. Further mechanism studies including Tet1 and Jmjd3 knockdown/inhibition experiments revealed that both the 5hmC and H3K27m3 changes, specifically in the progenitor cells, are indispensible for the VC-mediated mDA neuron differentiation. We finally show that in Svct2 knockout mouse embryos, mDA neuron formation in the developing midbrain decreased along with the 5hmC/H3k27m3 changes. These findings together indicate an epigenetic role of VC in midbrain DA neuron development. Stem Cells 2015;33:1320–1332

Use of the physiological mechanisms promoting midbrain DA (mDA) neuron survival seems an appropriate option for developing treatments for Parkinson's disease (PD). mDA neurons are specifically marked by expression of the transcription factors Nurr1 and Foxa2. We show herein that Nurr1 and Foxa2 interact to protect mDA neurons against various toxic insults, but their expression is lost during aging and degenerative processes. In addition to their proposed cell-autonomous actions in mDA neurons, forced expression of these factors in neighboring glia synergistically protects degenerating mDA neurons in a paracrine mode. As a consequence of these bimodal actions, adeno-associated virus (AAV)-mediated gene delivery of Nurr1 and Foxa2 in a PD mouse model markedly protected mDA neurons and motor behaviors associated with nigrostriatal DA neurotransmission. The effects of the combined gene delivery were dramatic, highly reproducible, and sustained for at least 1 year, suggesting that expression of these factors is a promising approach in PD therapy.

Aims Antipsychotic-induced autonomic dysregulation may lead to a wide range of subjective side-effects in schizophrenia patients. Using heart rate variability (HRV) measures, we prospectively examined the relationship between subjective side-effects and cardiac autonomic regulation in unmedicated schizophrenia patients. Methods Forty-five unmedicated schizophrenia patients were assessed for antipsychotic-associated side-effects and HRV parameters at baseline and after 6 weeks of treatment. Psychiatric symptoms and subjective side-effects were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Liverpool University Neuroleptic Side-effect Rating Scale (LUNSERS). Results Correlations between subjective adverse effects and HRV measures at baseline and at week 6 varied. Nonetheless, the changes in the psychic side-effects domain were significantly correlated with the changes in time-domain HRV measures and sample entropy (SampEn). In addition, the change in SampEn was significantly associated with that in the scores of extrapyramidal, anticholinergic, miscellaneous, and red herring domains as well as the mean total LUNSERS score. Conclusion Baseline HRV measures may predict clinical response and adverse events associated with treatment adherence. Also, subjective side-effects may correspond well with the changes in neurocardiac dynamics, and the changes in SampEn may effectively reflect subjective discomfort in patients receiving antipsychotic treatment.

Understanding how dopamine (DA) phenotypes are acquired in midbrain DA (mDA) neuron development is important for bioassays and cell replacement therapy for mDA neuron-associated disorders. Here, we demonstrate a feed-forward mechanism of mDA neuron development involving Nurr1 and Foxa2. Nurr1 acts as a transcription factor for DA phenotype gene expression. However, Nurr1-mediated DA gene expression was inactivated by forming a protein complex with CoREST, and then recruiting histone deacetylase 1 (Hdac1), an enzyme catalyzing histone deacetylation, to DA gene promoters. Co-expression of Nurr1 and Foxa2 was established in mDA neuron precursor cells by a positive cross-regulatory loop. In the presence of Foxa2, the Nurr1-CoREST interaction was diminished (by competitive formation of the Nurr1-Foxa2 activator complex), and CoREST-Hdac1 proteins were less enriched in DA gene promoters. Consequently, histone 3 acetylation (H3Ac), which is responsible for open chromatin structures, was strikingly increased at DA phenotype gene promoters. These data establish the interplay of Nurr1 and Foxa2 as the crucial determinant for DA phenotype acquisition during mDA neuron development.

The intracellular Raf-Erk signaling pathway is activated during neural stem cell (NSC) proliferation, and neuronal and astrocytic differentiation. A key question is how this signal can evoke multiple and even opposing NSC behaviors. We show here, using a constitutively active Raf (ca-Raf), that Raf-Erk activation in NSCs induces neuronal differentiation in a cell-autonomous manner. By contrast, it causes NSC proliferation and the formation of astrocytes in an extrinsic autocrine/paracrine manner. Thus, treatment of NSCs with medium (CM) conditioned in ca-Raf-transduced NSCs (Raf-CM; RCM) became activated to form proliferating astrocytes resembling radial glial cells (RGCs) or adult-type NSCs. Infusion of Raf-CM into injured mouse brains caused expansion of the NSC population in the subventricular zone, followed by the formation of new neurons that migrated to the damaged site. Our study shows an example how molecular mechanisms dissecting NSC behaviors can be utilized to develop regenerative therapies in brain disorders.

The original properties of tissue-specific stem cells, regardless of their tissue origins, are inevitably altered during in vitro culturing, lessening the clinical and research utility of stem cell cultures. Specifically, neural stem cells derived from the ventral midbrain lose their dopamine neurogenic potential, ventral midbrain-specific phenotypes, and repair capacity during in vitro cell expansion, all of which are critical concerns in using the cultured neural stem cells in therapeutic approaches for Parkinson's disease. In this study, we observed that the culture-dependent changes of neural stem cells derived from the ventral midbrain coincided with loss of RNA-binding protein LIN28A expression. When LIN28A expression was forced and sustained during neural stem cell expansion using an inducible expression-vector system, loss of dopamine neurogenic potential and midbrain phenotypes after long-term culturing was blocked. Furthermore, dopamine neurons that differentiated from neural stem cells exhibited remarkable survival and resistance against toxic insults. The observed effects were not due to a direct action of LIN28A on the differentiated dopamine neurons, but rather its action on precursor neural stem cells as exogene expression was switched off in the differentiating/differentiated cultures. Remarkable and reproducible behavioural recovery was shown in all Parkinson's disease rats grafted with neural stem cells expanded with LIN28A expression, along with extensive engraftment of dopamine neurons expressing mature neuronal and midbrain-specific markers. These findings suggest that LIN28A expression during stem cell expansion could be used to prepare therapeutically competent donor cells.

Evidence from previous studies suggests autonomic dysregulation in patients with major depressive disorder (MDD). Antidepressant treatment may also affect central autonomic function. We investigated whether the type of antidepressant might be associated with the pattern of cardiorespiratory coordination in non-depressed women with recurrent MDD. Resting electrocardiograms and respiratory signals were simultaneously recorded from 38 euthymic women with recurrent MDD who were treated with either escitalopram (n=19) or venlafaxine (n=19) monotherapy and from 38 healthy women. Linear measures of heart rate variability were extracted to assess cardiac autonomic control. Sample entropy (SampEn) was computed to assess the complexity of heart rate and respiratory signals, and cross-SampEn was calculated to measure the nonlinear interaction of both signals. Significant decreases in the cardiovagal tone and cardiorespiratory coupling of women with recurrent MDD receiving venlafaxine, and tendencies toward lower cardiovagal tone and cardiorespiratory coupling in women with recurrent MDD receiving escitalopram were observed when compared with healthy controls. Effect sizes for these differences were large between women receiving venlafaxine and healthy controls. We found a positive association between cardiorespiratory decoupling and venlafaxine dose. Norepinephrine-enhancement, within a therapeutic dose range, seems to be closely associated with decreased vagal tone and reduced nonlinear coupling between heart rate and respiration in euthymic women with recurrent MDD. However, the effects of serotonin enhancement on cardiovagal tone should be considered. Our results suggest that the pharmacodynamic properties of antidepressants may affect autonomic regulation of women with recurrent MDD even in euthymic state.

Neural stem/progenitor cell (NSC/NPC) cultures can be a source of dopamine (DA) neurons for experimental and transplantation purposes. Nurr1, a steroid receptor transcription factor, can overcome the limitations associated with differentiation of cultured NPCs into DA neurons. However, forced Nurr1 expression in NPC cultures generates non-neuronal and/or immature DA cells. We show here that the Nurr1 level and period of expression crucially affect the differentiation and maturation of Nurr1-induced DA neurons. Mature DA neurons were generated by manipulating Nurr1 expression patterns to resemble those in the developing midbrain.

Objective Alterations in neuroelectrical activities coincide with major depressive disorder (MDD). This study examines the pattern of cerebral activity and cardiac autonomic parameters of euthymic women with recurrent MDD. Methods Resting electroencephalograms and electrocardiograms were recorded from 20 women with MDD receiving escitalopram and 40 matched and healthy women. We computed frontal alpha asymmetry to evaluate the interhemispheric balance. Parameters of heart rate variability were extracted to assess cardiac autonomic control. Sample entropy was used to assess the complexity of neurocardiac dynamics. The relationship between cardiovagal activity and alpha electroencephalogram was examined with a coherence analysis. Results Multivariable analysis of variance revealed a differential pattern of psychophysiologic variables between MDD patients and controls (p = .03). MDD was associated with a tendency toward lower left frontal activity (-0.06 [standard deviation = 0.14] versus 0.04 [0.17] lnμV(2), p = .04). Discriminant analysis demonstrated more right frontal activation, a lower high-frequency heart rate power spectrum, and a higher ratio of the low- to high-frequency heart rate power spectrum in patients with MDD compared with controls. Residual depressive symptoms (r = -0.09 to 0.11, p = .63-.99) and escitalopram dosage (r = -0.09 to 0.28, p = .22-.84) were not correlated with autonomic measures. Coherence between normalized high-frequency component of the heart rate power spectrum and alpha power was not significant (F3, p = .27; F4, p = .16). Conclusions Euthymic women with recurrent MDD have a distinctive psychophysiologic profile. This profile may reflect altered frontal activation and a reduced cardiovagal tone in depression.

BACKGROUND The aim of this study was to investigate the relationship between heart rate variability (HRV), the Framingham risk score (FRS), and the 10-year risk of coronary heart disease (CHD) development among Korean adults. METHODS The subjects were 85 healthy Korean adults recruited from a health check-up center. The FRS and 10-year risk of CHD development were calculated. RESULTS The FRS in men was inversely correlated with the standard deviation of all normal to normal RR-intervals (SDNN); the root mean square successive difference (RMSSD); the percentage of successive normal cardiac inter-beat intervals greater than 20 ms, 30 ms, and 50 ms (pNN20, pNN30, pNN50); the low frequency (LF); and the high frequency (HF) (P < 0.05). There was no significant relationship between the FRS and HRV in women. Overall, in the receiver operating characteristic (ROC) analysis, the RMSSD, HF, SDNN, LF, LF/HF ratio, and pNN30 predicted an increased 10-year CHD risk. After adjusting for sex and body mass index, those with greater than one standard deviation in the RMSSD, HF, and LF had a 52-59% reduction in their 10-year risk of CHD development ≥ 10%. CONCLUSION This study therefore indicates that the HRV indices, particularly SDNN, RMSSD, pNN30, LF, and HF may be useful parameters for the assessment of CHD risk. Most notably, the usefulness of these HRV measures as indicators for CHD risk evaluation may be greater among men than among women.

Parkinson disease (PD) involves the selective loss of midbrain dopamine (mDA) neurons and is a possible target disease for stem cell-based therapy. Human induced pluripotent stem cells (hiPSCs) are a potentially unlimited source of patient-specific cells for transplantation. However, it is critical to evaluate the safety of hiPSCs generated by different reprogramming methods. Here, we compared multiple hiPSC lines derived by virus- and protein-based reprogramming to human ES cells (hESCs). Neuronal precursor cells (NPCs) and dopamine (DA) neurons delivered from lentivirus-based hiPSCs exhibited residual expression of exogenous reprogramming genes, but those cells derived from retrovirus- and protein-based hiPSCs did not. Furthermore, NPCs derived from virus-based hiPSCs exhibited early senescence and apoptotic cell death during passaging, which was preceded by abrupt induction of p53. In contrast, NPCs derived from hESCs and protein-based hiPSCs were highly expandable without senescence. DA neurons derived from protein-based hiPSCs exhibited gene expression, physiological, and electrophysiological properties similar to those of mDA neurons. Transplantation of these cells into rats with striatal lesions, a model of PD, significantly rescued motor deficits. These data support the clinical potential of protein-based hiPSCs for personalized cell therapy of PD.

Background: The aim of the present study was to characterize the heart rate dynamics of sinus bradycardia (SB) from sinus node dysfunction (SND) using non-linear dynamical system analysis. No data are yet available on how the dynamics change in the presence of SND. Methods and Results: Conventional time and frequency domain analysis, the short- (DFAα1) and intermediate-term fractal scaling exponent (DFAα2), approximate entropy (ApEn) and sample entropy (SampEn) were calculated in 60-min sinus RR interval data of SB from 24-h ambulatory electrocardiograms of 110 patients: 44 SND patients, 44 age-matched controls, and 22 younger controls. All of the time and frequency domain parameters, ApEn and SampEn, were significantly reduced in the age-matched control group, compared with the young control group. DFAα1 and DFAα2 increased with aging. Both the DFAα1 and DFAα2 of SND patients were paradoxically reduced, which was not appropriate for their age. Only the percentage of consecutive RR intervals with absolute differences >50ms (pNN50), low-frequency power, and DFAα2 made a significant contribution to prediction of SND on logistic regression analysis. Among them, DFAα2 was the most significant variable for prediction of SND (odds ratio, 0.927; 95% confidence interval: 0.888-0.969, P=0.001). DFAα2 remained as a significant variable for prediction of SND, when compared with overall control patients, combining the 2 control groups. Conclusions: Inappropriate reduction of DFAα2 is a robust measure and could be an adjunctive tool for improvement of diagnostic performance in detection of SND. (Circ J 2011; 75: 2775-2780)

Background Coherence (COH) and Phase Locking Value (PLV) may have considerable potentials for investigating anomalies of functional connectivity in schizophrenia but results are still conflicting. This study is aimed to investigate relationships between plasma levels of clozapine (p-CZP) and norclozapine (p-NCZP), and total and cognitive factor scores of Positive and Negative Syndrome Scale (PANSS-T, -C), and functional connectivity by COH and PLV. Methods Fifty-eight patients who were diagnosed as schizophrenia with DSM-5 criteria and under CZP were recruited (duration of illness, 15.5 ± 8.0 years; duration of CZP, 6.8 ± 4.6 years; mean daily dose of CZP, 233.6 ± 88.4 mg). COH and PLV were calculated with Neurophysiological Biomarker Toolbox from qEEG and were averaged from the signals of electrodes in the designated brain regions, frontal (F), temporal (T), central (C) and occipitoparietal (OP). For interhemispheric connectivity, electrodes except all midline channels were combined into Odd (O) and Even (E). The results were presented at ≥0.30 of Spearman correlation. Results 1) Correlation coefficient between p-CZP and p-NCZP was 0.84, and those of CZP dose with p-CZP and p-NCZP were 0.38 and 0.53, respectively. 2) p-CZP showed correlations with OCEC in delta and alpha, OTEC in delta, OCEOP in theta, OTEF in alpha, and OOPEF in gamma band in COH, and OOPEOP in beta band in PLV. 3) p-NCZP showed correlations with ETEOP in delta, theta, and gamma, OCEC in delta and alpha, OFOC and OCEOP in delta, OFET and OTET in alpha, OCEF in beta, OOPEC in gamma band in COH, and with ETEOP in delta, theta, and beta, OTET and OCEC in alpha, OCEF in beta band in PLV. 4) CZP dose showed correlations with ETEC in beta and gamma, ETEOP in theta, OCEF in alpha, OTET in beta, OOPEF and OOPET in gamma band in COH, and with OTET in alpha and beta, ETEOP in theta, OTEOP in alpha, ETEC in beta, OFOC in gamma band in PLV. 5) PANSS-T showed correlations with OFEOP and EFEOP in alpha, OCEOP in beta, OTOC and OTEF in gamma band in COH, and with OTEF in beta and gamma, OFET in delta, OOPEF in beta, OTOC and OCEOP in gamma band in PLV. 6) PANSS-C showed correlations with EFEOP in delta, theta, alpha, and beta, OOPEOP in delta, alpha, and beta, OFET and OTEF both in alpha and beta, OOPEF in delta, OFEOP in alpha, OFEC and OCEOP in beta, OTOC in gamma band in COH, and with EFEOP in theta, alpha, and beta, OFEOP and OOPEOP both in alpha and beta, OFET in delta and beta, OTOC, OOPEF, OOPEOP in beta, OTOC and OCEOP in PLV. 7) PANSS-T and -C showed no correlations with p-CZP, p-NCZP and CZP dose. 8) However, the clinical and drug variables showed significant simultaneous correlation with certain functional connectivity, but sometimes the direction correlation was opposite. Discussion The relationship between functional connectivity and clozapine parameters seems to demonstrate inter- and intra-hemispheric connections in brain regions. However, there were same and/or opposite directions of correlations between COH and PLV dependent EEG band frequencies and clinical and drug variables. Taken together, investigating the functional connectivity with COH and PLV could give the information about p-CZP and p-NCZP before the laboratory reports, the degree of psychopathology in patients with schizophrenia under CZP, and the differentiations of surface symptoms whether derived from pathophysiology of schizophrenia or from clozapine effects.

Effective dopamine (DA) neuron differentiation from neural precursor cells (NPCs) is prerequisite for precursor/stem cell-based therapy of Parkinson's disease (PD). Nurr1, an orphan nuclear receptor, has been reported as a transcription factor that can drive DA neuron differentiation from non-dopaminergic NPCs in vitro. However, Nurr1 alone neither induces full neuronal maturation nor expression of proteins found specifically in midbrain DA neurons. In addition, Nurr1 expression is inefficient in inducing DA phenotype expression in NPCs derived from certain species such as mouse and human. We show here that Foxa2, a forkhead transcription factor whose role in midbrain DA neuron development was recently revealed, synergistically cooperates with Nurr1 to induce DA phenotype acquisition, midbrain-specific gene expression, and neuronal maturation. Thus, the combinatorial expression of Nurr1 and Foxa2 in NPCs efficiently yielded fully differentiated nigral (A9)-type midbrain neurons with clearly detectable DA neuronal activities. The effects of Foxa2 in DA neuron generation were observed regardless of the brain regions or species from which NPCs were derived. Furthermore, DA neurons generated by ectopic Foxa2 expression were more resistant to toxins. Importantly, Foxa2 expression resulted in a rapid cell cycle exit and reduced cell proliferation. Consistently, transplantation of NPCs transduced with Nurr1 and Foxa2 generated grafts enriched with midbrain-type DA neurons but reduced number of proliferating cells, and significantly reversed motor deficits in a rat PD model. Our findings can be applied to ongoing attempts to develop an efficient and safe precursor/stem cell-based therapy for PD.

The cardiac autonomic dysfunction has been reported in patients with schizophrenia. Heart rate variability (HRV) provides non-invasive indices of cardiac autonomic modulation. This study examined whether patients with schizophrenia may show a distinctive pattern of HRV compared to healthy controls. Nine measures of time, frequency and complexity domains were extracted from 5-min resting evaluation of HRV in 30 unmedicated patients with schizophrenia and 30 age- and gender-matched controls. In addition to inferential statistics, a hierarchical clustering (HC) was used to examine difference in the interrelationships among HRV measures between the two groups. Multivariate analysis of variance revealed a significant group effect. Significantly lower sample entropy (SampEn) and a trend towards a higher ratio of low- to high frequency (LF/HF) were observed in the schizophrenia group. In the results of HC using Ward's method, SampEn co-clustered with LF/HF ratio in patients with schizophrenia compared to the separation of LF/HF ratio in healthy controls. In concert with decreased parasympathetic activity, low complexity of heart rate dynamics may reduce adaptability of cardiovascular system to changes in internal or external environment, thus increasing the risk of cardiovascular events. Diverse HRV measures combined in a multivariate fashion appear to be useful in understanding the pattern of neurocardiac modulation in patients with schizophrenia.

Neural precursor cells (NPCs) are regarded as a promising source of donor cells in transplantation-based therapies for neurodegenerative disorders. However, poor survival and limited neuronal differentiation of the transplanted NPCs remain critical limitations for developing therapeutic strategies. In this study, we investigated the effects of the proneural basic helix-loop-helix (bHLH) transcription factors Mash1 and Neurogenin 2 (Ngn2) in neuronal differentiation and survival of NPCs. Induction of Mash1 or Ngn2 expression strikingly enhanced neuronal differentiation of cultured NPCs in vitro. Ngn2-transduced NPCs underwent a rapid cell cycle arrest, which often accompanies differentiation. In contrast, cells continuously expanded upon Mash1 expression during NPC differentiation. Notably, sonic hedgehog (SHH) was upregulated by Mash1 and mediated the proliferative and survival effects of Mash1 on NPCs. Upon transplantation into adult rat brains, Mash1-expressing NPCs yielded large grafts enriched with neurons compared to control LacZ-transduced NPCs. Interestingly, enhancements in neuronal yield, as well as in donor cell survival, were also achieved by transplanting Ngn2-transduced NPCs. We show that a differentiation stage- and cell density-dependent survival effect of Ngn2 involves neurotrophin3 (NT3)/TrkC-mediated signaling. Together, these findings suggest potential benefits of bHLH gene manipulation to develop successful transplantation strategies for brain disorders.

Recent groundbreaking work has demonstrated that combined expression of the transcription factors Brn2, Ascl1, and Myt1L (BAM; also known as Wernig factors) convert mouse fibroblasts into postmitotic neuronal cells. However, questions remain regarding whether trans-conversion is achieved directly or involves an intermediary precursor stage. Trans-conversion toward expandable neural precursor cells (NPCs) is more useful than direct one-step neuron formation with respect to yielding a sufficient number of cells and the feasibility of manipulating NPC differentiation toward certain neuron subtypes. Here, we show that co-expression of Wernig factors and Bcl-xL induces fibroblast conversion into NPCs (induced NPCs (iNPCs)) that are highly expandable for >100 passages. Gene expression analyses showed that the iNPCs exhibited high expression of common NPC genes but not genes specific to defined embryonic brain regions. This finding indicated that a regional identity of iNPCs was not established. Upon induction, iNPCs predominantly differentiated into astrocytes. However, the differentiation potential was not fixed and could be efficiently manipulated into general or specific subtypes of neurons by expression of additional genes. Specifically, overexpression of Nurr1 and Foxa2, transcription factors specific for midbrain dopamine neuron development, drove iNPCs to yield mature midbrain dopamine neurons equipped with presynaptic DA neuronal functions. We further assessed the therapeutic potential of iNPCs in Parkinson disease model rats. Background: Fibroblasts can be converted into neurons by transduction with BAM. Results: Multiple lines of evidence were used to demonstrate that a significant percentage of BAM-transduced fibroblasts can be converted into iNPCs by co-expression of Bcl-xL. Conclusion: BAMX-derived iNPCs were expandable over multiple passages in vitro, and differentiation phenotypes of iNPCs were readily manipulated by specific developmental cues. Significance: Bcl-xL has a critical role in neural precursor cell conversion.

The relationship between antipsychotic-induced extrapyramidal syndrome (EPS) and the autonomic neurocardiac function was examined in 57 schizophrenic patients treated with atypical antipsychotics. Comprehensive assessments of EPS and heart rate dynamics were performed. There was a significant negative correlation of non-hypokinetic parkinsonism, akathisia, and dyskinesia with several linear and novel non-linear heart rate dynamics measures, suggesting reduced neurocardiac dynamics associated with some forms of EPS. Assessment of heart rate dynamics may be useful for the detection of these adverse effects and may serve as a useful non-invasive method providing a dynamic window into the alterations of complex neuronal activity.

Dysregulation of forkhead box protein A2 (Foxa2) expression in fetal ventral mesencephalon (VM)-derived neural precursor cells (NPCs) appears to be associated with the loss of their potential to differentiate into dopaminergic (DA) neurons after mitogenic expansion in vitro, hindering their efficient use as a transplantable cell source. Here, we report that epigenetic activation of Foxa2 in VM-derived NPCs by inducing histone hyperacetylation rescues the mitogenic-expansion-dependent decrease of differentiation potential to DA neurons. The silencing of Foxa2 gene expression after expansion is accompanied by repressive histone modifications, including hypoacetylation of histone H3 and H4 and trimethylation of H3K27 on the Foxa2 promoter, as well as on the global level. In addition, histone deacetylase 7 (HDAC7) is highly expressed during differentiation and recruited to the Foxa2 promoter. Induction of histone acetylation in VM-derived NPCs by either knockdown of HDAC7 or treatment with the HDAC inhibitor apicidin upregulates Foxa2 expression via hyperacetylation of H3 and a decrease in H3K27 trimethylation on the promoter regions, leading to the expression of DA neuron developmental genes and enhanced differentiation of DA neurons. These effects are antagonized by the expression of shRNAs specific for Foxa2 but enhanced by shRNA for HDAC7. Collectively, these findings indicate that loss of differentiation potential of expanded VM-derived NPCs is attributed to a decrease in Foxa2 expression and suggest that activation of the endogenous Foxa2 gene by epigenetic regulation might be an approach to enhance the generation of DA neurons.

Healthcare systems are evolving from simple medical devices to ubiquitous healthcare systems working at anytime and anywhere. In particular, acquisition and transmission of vital signs from wearable devices with biosensors will be soon realized in our daily lives. Interestingly, when vital signs such as Electrocardiogram (ECG), respiration and the motion data are collected and accumulated, they become a kind of big data, which will be eventually a crucial clue for monitoring health in everyday life and preventing from diseases. This paper proposes a big data framework for u-healthcare systems that provide healthcare services based upon the analysis of the big data of vital signs. The framework includes methods for provision of real-time services as well as for transmission and analysis of the data. It employs an open standard platform to secure interoperability among the data and different devices. The proposed framework was implemented and tested in terms of the motion data from accelerometers.

Antipsychotic-induced autonomic dysregulation may lead to a wide range of subjective side-effects in schizophrenia patients. Using heart rate variability (HRV) measures, we prospectively examined the relationship between subjective side-effects and cardiac autonomic regulation in unmedicated schizophrenia patients.Forty-five unmedicated schizophrenia patients were assessed for antipsychotic-associated side-effects and HRV parameters at baseline and after 6 weeks of treatment. Psychiatric symptoms and subjective side-effects were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Liverpool University Neuroleptic Side-effect Rating Scale (LUNSERS).Correlations between subjective adverse effects and HRV measures at baseline and at week 6 varied. Nonetheless, the changes in the psychic side-effects domain were significantly correlated with the changes in time-domain HRV measures and sample entropy (SampEn). In addition, the change in SampEn was significantly associated with that in the scores of extrapyramidal, anticholinergic, miscellaneous, and red herring domains as well as the mean total LUNSERS score.Baseline HRV measures may predict clinical response and adverse events associated with treatment adherence. Also, subjective side-effects may correspond well with the changes in neurocardiac dynamics, and the changes in SampEn may effectively reflect subjective discomfort in patients receiving antipsychotic treatment.

Cell culture of human-derived neural stem cells (NSCs) is a useful tool that contributes to our understanding of human brain development and allows for the development of therapies for intractable human brain disorders. Human NSC (hNSC) cultures, however, are not commonly used, mainly because of difficulty with consistently maintaining the cells in a healthy state. In this study, we show that hNSC cultures, unlike NSCs of rodent origins, are extremely sensitive to insulin, an indispensable culture supplement, and that the previously reported difficulty in culturing hNSCs is likely because of a lack of understanding of this relationship. Like other neural cell cultures, insulin is required for hNSC growth, as withdrawal of insulin supplementation results in massive cell death and delayed cell growth. However, severe apoptotic cell death was also detected in insulin concentrations optimized to rodent NSC cultures. Thus, healthy hNSC cultures were only produced in a narrow range of relatively low insulin concentrations. Insulin-mediated cell death manifested not only in all human NSCs tested, regardless of origin, but also in differentiated human neurons. The underlying cell death mechanism at high insulin concentrations was similar to insulin resistance, where cells became less responsive to insulin, resulting in a reduction in the activation of the PI3K/Akt pathway critical to cell survival signaling.

Previous studies have suggested the utility of nonlinear complexity measures of heart rate variability (HRV) in evaluating the regulatory capacity of the neuroautonomic system. The purpose of the present study was to investigate the effects of clozapine on the nonlinear complexity measures of HRV in patients with treatment-resistant schizophrenia to find novel electrophysiological markers that indicate response to clozapine treatment. Forty patients with treatment-resistant schizophrenia were evaluated during 8 weeks of clozapine monotherapy. For nonlinear complexity measures of HRV, the approximate entropy (ApEn) and sample entropy (SampEn) values were obtained. The response rate to clozapine was 37.5%. The results of multivariate analysis of covariance revealed that the ApEn and the SampEn values of HRV at week 8 were significantly higher in the responders than in the nonresponders. Repeated-measures analysis of covariance showed a significant group by time interaction effect in the ApEn and SampEn indices. The responder group showed an increasing pattern of change in these complexity measures after administration of clozapine, whereas the nonresponder group showed a decreasing pattern of change. These results suggest that the nonlinear dynamic complexity measures of HRV, which indicate the irregularity and complexity of the biosystem, may be useful in evaluating the therapeutic changes of neuroautonomic function in schizophrenia. The response to clozapine treatment is expected to be more favorable when the plasticity of the neuroautonomic system reflected in the nonlinear complexity measures is high.

The aim of the present study was to characterize the heart rate dynamics of sinus bradycardia (SB) from sinus node dysfunction (SND) using non-linear dynamical system analysis. No data are yet available on how the dynamics change in the presence of SND.Conventional time and frequency domain analysis, the short- (DFAα(1)) and intermediate-term fractal scaling exponent (DFAα(2)), approximate entropy (ApEn) and sample entropy (SampEn) were calculated in 60-min sinus RR interval data of SB from 24-h ambulatory electrocardiograms of 110 patients: 44 SND patients, 44 age-matched controls, and 22 younger controls. All of the time and frequency domain parameters, ApEn and SampEn, were significantly reduced in the age-matched control group, compared with the young control group. DFAα(1) and DFAα(2) increased with aging. Both the DFAα(1) and DFAα(2) of SND patients were paradoxically reduced, which was not appropriate for their age. Only the percentage of consecutive RR intervals with absolute differences50ms (pNN(50)), low-frequency power, and DFAα(2) made a significant contribution to prediction of SND on logistic regression analysis. Among them, DFAα(2) was the most significant variable for prediction of SND (odds ratio, 0.927; 95% confidence interval: 0.888-0.969, P=0.001). DFAα(2) remained as a significant variable for prediction of SND, when compared with overall control patients, combining the 2 control groups.Inappropriate reduction of DFAα(2) is a robust measure and could be an adjunctive tool for improvement of diagnostic performance in detection of SND.

Understanding midbrain dopamine (DA) neuron differentiation is of importance, because of physiological and clinical implications of this neuronal subtype. We show that prolonged membrane depolarization induced by KCl treatment promotes DA neuron differentiation from neural precursor cells (NPCs) derived from embryonic ventral midbrain (VM). Interestingly, the depolarization-induced increase of DA neuron yields was not abolished by L-type calcium channel blockers, along with no depolarization-mediated change of intracellular calcium level in the VM-derived NPCs (VM-NPCs), suggesting that the depolarization effect is due to a calcium-independent mechanism. Experiments with labeled DA neuron progenitors indicate that membrane depolarization acts at the differentiation fate determination stage and promotes the expression of DA phenotype genes (tyrosine hydroxylase [TH] and DA transporter [DAT]). Recruitment of Nurr1, a transcription factor crucial for midbrain DA neuron development, to the promoter of TH gene was enhanced by depolarization, along with increases of histone 3 acetylation (H3Ac) and trimethylation of histone3 on lysine 4 (H3K4m3), and decreases of H3K9m3 and H3K27m3 in the consensus Nurr1 binding regions of TH promoter. Depolarization stimuli on differentiating VM-NPCs also induced dissociation of methyl CpG binding protein 2 and related repressor complex molecules (repressor element-1 silencing transcription factor corepressor and histone deacetylase 1) from the CpG sites of TH and DAT promoters. Based on these findings, we suggest that membrane depolarization promotes DA neuron differentiation by opening chromatin structures surrounding DA phenotype genes and inhibiting the binding of corepressors, thus allowing transcriptional activators such as Nurr1 to access DA neuron differentiation gene promoter regions.

Determining the exact duration of seizure activity is an important factor for predicting the efficacy of electroconvulsive therapy (ECT). In most cases, seizure duration is estimated manually by observing the electroencephalogram (EEG) waveform. In this article, we propose a method based on sample entropy (SampEn) that automatically detects the termination time of an ECT-induced seizure. SampEn decreases during seizure activity and has its smallest value at the boundary of seizure termination. SampEn reflects not only different states of regularity and complexity in the EEG but also changes in EEG amplitude before and after seizure activity. Using SampEn, we can more precisely determine seizure termination time and total seizure duration.

Neurocardiac dysregulation has been reported in schizophrenia. Indices of heart rate variability (HRV) are useful in assessing the status of cardiac autonomic regulation. We explored within-subject changes in HRV indices in acutely ill patients with schizophrenia treated with risperidone. Sixteen medication-naive or medication-free patients with DSM-IV schizophrenia completed electrocardiogram (ECG) assessments at baseline and after six weeks of treatment with risperidone. Indices of HRV were extracted from 5-min resting ECG recordings and compared to those obtained from control subjects matched for age and gender. Psychiatric and drug-induced extrapyramidal symptoms were assessed by the Positive and Negative Syndrome Scale (PANSS) and the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS). In comparison with matched controls, patients with acute schizophrenia showed lower values of time-domain measures, lower high-frequency power (HF) and a higher ratio of low to high frequency (LF/HF). In the within-subject analyses, a significant decrease in LF/HF was associated with risperidone treatment. In addition, LF/HF, which initially co-clustered with clinical variables, congregated with other HRV measures after the six-week risperidone treatment. These results indicate that, in the therapeutic process, risperidone treatment may exert a beneficial influence on the sympathovagal imbalance in acute schizophrenia.

In order to perform a real-time analysis of a physiological signal, such as heart rate variability (HRV), obtained from a ubiquitous health care system, we propose some effective measures of complexity, which are basing on the symbolic dynamics. In symbolic dynamics, HRV extracted from an electrocardiogram is transformed into a symbolic sequence in the coarse-graining process where the difference of periods between consecutive heartbeats plays a threshold for determining the type of symbols in the symbolic return map. Quantification of a symbolic sequence was performed by using the generalized symbolic measures; pNNx, pWx, CNx, and CSEx in which x denotes a threshold of coarse-graining symbolization. By varying the threshold x, we comprehensively examined the symbolic dynamic parameters for normal controls with normal sinus rhythms and the presumed patients with atrial fibrillation, or congestive heart failure, and identified the optimal threshold distinguishing the normal group from the abnormal group. The range of optimal thresholds was found at 10 ∼ 25 ms, which is far below from the conventional standard of 50 ms. We demonstrate that pNNx, pWx, CNx, and CSEx are useful algorithms for the real-time analysis of HRV acquired from the ubiquitous health care system as well as for the assessment of the emergent alterations in a heart dynamics.

Background New methods based on nonlinear theory have been developed to give more insight into complex heart rate (HR) dynamics. This study was designed to test the hypothesis that altered HR dynamics, as analyzed with complexity and fractal measures, may precede the spontaneous onset of paroxysmal atrial fibrillation (PAF). Secondly, the difference in the temporal change of these measurements between the different types of atrial fibrillation (AF) was assessed. Methods and Results From 105 Holter tapes in which PAF was recorded, 44 PAF (≥5 min) episodes in 33 patients (22 men, 58±12 years), preceded by sinus rhythm for more than 1 h, were selected and submitted to time-and frequency-domain HR variability analyses, along with detrended fluctuation analysis, approximate entropy (ApEn) and sample entropy (SampEn). The 60 min before the onset of AF were divided into 6 10-min periods and studied using repeated measures ANOVA. PAF episodes were divided into 3 subgroups: an increased HF component and decreased L/H ratio (vagal type, n=20); increased L/H ratio and decreased HF component (sympathetic type, n=14); and non-related type (n=10). None of the time- or frequency-domain parameters showed any significant change before AF in any type of AF. The α1 showed a tendency to decrease before the onset of AF and the change in α1 was divergent according to the AF type. The ApEn decreased before the onset of AF (1.005±0.046, 60-50 min before AF to 0.894±0.052, 10-0 min before AF; p=0.032). The SampEn also decreased progressively before the start of AF (1.165± 0.085, 60-50 min before AF to 0.887 ±0.077, 10-0 min before AF, p=0.003). The decrease in both the ApEn and SampEn was irrespective of the AF type. Conclusions A reduction in the ApEn and SampEn, which reflects the nonlinear complexity of HR variability, is a hallmark of altered HR dynamics preceding the spontaneous onset of AF. (Circ J 2006; 70: 94 - 99)

We discuss the virial coefficients for a gas of anyons in the strong magnetic field at the low temperature.

1. In order to find the electroencephalographic (EEG) parameters that reflect the effect of clozapine in schizophrenic patients, the authors applied various non-linear analyses on multi-channel EEG data drawn from patients before and after a therapeutic trial of clozapine. 2. The correlation dimension was difficult to extract from our limited time series EEG data and the authors did not find a meaningful assocation with clozapine use. The primary Lyapunov exponent could be reliably calculated but also did not reflect the effect of clozapine. 3. However, the mutual cross-prediction (MCP) algorithm showed potentially meaningful results. The driving system was shifted to the frontal channels after a 4-week trial with clozapine. Moreover, MCP might have a value as a predictor of treatment response. 4. Although preliminary in nature, the MCP might have greater power for interpreting complex changes from channel to channel in EEG induced by clozapine.

Smart clothes containing nanoweb-based biosensors to acquire vital signs, known as wellness wear, have great potentiality as a wearable computing device that helps care for and promote health. This paper firstly presents a wellness wear system that we are currently developing, primarily discussing two crucial technologies of biosensors and digital yarns transmitting data, which play an important role to support comfort and wearability. Secondly, it also presents both software architecture, essential as a fundamental basis to provide sustainable and seamless various medical services, and a software application involving a stress tracker working together with the wellness wear system. The stress tracker as an example of healthcare devices, running on an Android-based smart phone, analyses the electrocardiograph (ECG) data obtained from wellness wear and provides a programme to evaluate users’ autonomous nervous system (ANS) which controls mental stress, and to give them proper biofeedback.

Objective The percentage of successive normal cardiac interbeat intervals greater than 50 msec (pNN50) is a widely used heart rate variability measure, which is useful in identifying the neuroautonomic dysfunction of psychiatric disorders. However, pNN50 is only one member of a larger family of pNNx statistics, where x is greater than 0 msec. The potential application of the general pNNx statistics has not yet been explored in the psychiatric field. The authors examined the pNNx statistics in clozapine-treated subjects and normal controls to evaluate the usefulness of the general pNNx statistics. Methods Sixty-one schizophrenic patients treated with clozapine and fifty-nine normal controls were evaluated. Probability values for the differences between the groups at each pNN value (range: pNN1-pNN100) were calculated using data obtained from a 30-minute electrocardiogram. Results The conventional pNN50 and pNNx values with x

Background and Objectives:The traditional indexes of heart rate (HR) variability may lack the ability to detect subtle, but important changes in HR behavior. Nonlinear heart rate variability (HRV) analysis methods that are based on chaos theory can reveal subtle abnormalities in the HR dynamics of patients with cardiovascular diseases. Therefore, we tested the validity of nonlinear analysis methods as markers to differentiate normal and abnormal HR dynamics in the cardiovascular disease state. Subjects and Methods:One-hundred patients were studied: 70 patients with left ventricular dysfunction (LVD), including 40 post-myocardial infarct patients (PMI) and 30 di- lated cardiomyopahty patients (DCM), and 30 age and gender-matched controls. One-hour, 6-hours (day and night each) and 24 hours of R-R interval data from 24-hour Holter recordings were subjected to the conventional time and frequency-domain analysis. The ApEn, short-term (α 1) and long-term (α2) scaling exponents of the detrended fluctuation analysis (DFA) and the power-law exponent (β) were also measured. Results:Conven- tional linear measures did not show a significant difference except for the VLF, lnLF and the LF/HF ratio between the controls and the LVD patients. Among the analyzed parameters, β, β2 and α1 were the most powerful dis- criminators. The β of the normal and LVD patients was -1.10±0.29 and -0.70±0.40, respectively (p

Background and Objectives:Heart rate variability (HRV) analysis, by conventional measures, for predicting the risk of atrial fibrillation (AF) has inherent shortcomings. Recently, nonlinear HRV analysis methods have been developed to reveal heart rate dynamics not evident from usual HRV measures. The purpose of this study was to test the hypothesis"heart rate dynamics are altered before the spontaneous onset of paroxysmal AF (PAF)" using algorithms derived from symbolic dynamics based on nonlinear system theory. Subjects and Methods: This study included 34 subjects (30 males, 59±9 years): 17 PAF patients and 17 gender and age-matched con- trols, who underwent 24-hour Holter ECG. The dynamics of one hour of normal sinus rhythm before the onset of AF were assessed using 4 different symbolization algorithms, and quantified by Shannon entropy (SE) and Renyi entropy (RE). Results:The SE, RE and Error-corrected SE (ECSE) were larger in the PAF than the con- trol patients when the raw R-R data was assessed (Algorithm I). However, when reconstructed time series, ex- pressed as the time difference between 2 successive R-R interval, were analyzed (Algorithm II, III and IV), the entropy of the PAF patients were consistently smaller than those of the controls. Of the 4 different symboliza- tion algorithms, algorithms II and III showed a significant difference in the SE, ECSE and RE between the PAF and the control patients (p