Longitudinal reduction in brain volume in patients with schizophrenia and its association with cognitive function

Establishing a brain biomarker for schizophrenia is strongly desirable not only to support diagnosis by psychiatrists but also to help track the progressive changes in the brain over the course of the illness. A brain morphological signature of schizophrenia was reported in a recent study and is defined by clusters of brain regions with reduced volume in schizophrenia patients compared to healthy individuals. This signature was proven to be effective at differentiating patients with schizophrenia from healthy individuals, suggesting that it is a good candidate brain biomarker of schizophrenia. However, the longitudinal characteristics of this signature have remained unclear. In this study, we examined whether these changes occurred over time and whether they were associated with clinical outcomes. We found a significant change in the brain morphological signature in schizophrenia patients with more brain volume loss than the natural, age-related reduction in healthy individuals, suggesting that this change can capture a progressive morphological change in the brain. We further found a significant association between changes in the brain morphological signature and changes in the full-scale intelligence quotient (IQ). The patients with IQ improvement showed preserved brain morphological signatures, whereas the patients without IQ improvement showed progressive changes in the brain morphological signature, suggesting a link between potential recovery of intellectual abilities and the speed of brain pathology progression. We conclude that the brain morphological signature is a brain biomarker that can be used to evaluate progressive changes in the brain that are associated with cognitive impairment due to schizophrenia.

Harmonizing multisite data with the ComBat method for enhanced Parkinson's disease diagnosis via DAT-SPECT

Background

Dopamine transporter single-photon emission computed tomography (DAT-SPECT) is a crucial tool for evaluating patients with Parkinson's disease (PD). However, its implication is limited by inter-site variability in large multisite clinical trials. To overcome the limitation, a conventional prospective correction method employs linear regression with phantom scanning, which is effective yet available only in a prospective manner. An alternative, although relatively underexplored, involves retrospective modeling using a statistical method known as "combatting batch effects when combining batches of gene expression microarray data" (ComBat).

Methods

We analyzed DAT-SPECT-specific binding ratios (SBRs) derived from 72 healthy older adults and 81 patients with PD registered in four clinical sites. We applied both the prospective correction and the retrospective ComBat correction to the original SBRs. Next, we compared the performance of the original and two corrected SBRs to differentiate the PD patients from the healthy controls. Diagnostic accuracy was assessed using the area under the receiver operating characteristic curve (AUC-ROC).

Results

The original SBRs were 6.13 ± 1.54 (mean ± standard deviation) and 2.03 ± 1.41 in the control and PD groups, respectively. After the prospective correction, the mean SBRs were 6.52 ± 1.06 and 2.40 ± 0.99 in the control and PD groups, respectively. After the retrospective ComBat correction, the SBRs were 5.25 ± 0.89 and 2.01 ± 0.73 in the control and PD groups, respectively, resulting in substantial changes in mean values with fewer variances. The original SBRs demonstrated fair performance in differentiating PD from controls (Hedges's g = 2.76; AUC-ROC = 0.936). Both correction methods improved discrimination performance. The ComBat-corrected SBR demonstrated comparable performance (g = 3.99 and AUC-ROC = 0.987) to the prospectively corrected SBR (g = 4.32 and AUC-ROC = 0.992) for discrimination.

Conclusion

Although we confirmed that SBRs fairly discriminated PD from healthy older adults without any correction, the correction methods improved their discrimination performance in a multisite setting. Our results support the utility of harmonization methods with ComBat for consolidating SBR-based diagnosis or stratification of PD in multisite studies. Nonetheless, given the substantial changes in the mean values of ComBat-corrected SBRs, caution is advised when interpreting them.

Contribution of amyloid and putative Lewy body pathologies in neuropsychiatric symptoms

OBJECTIVES

Neuropsychiatric symptom could be useful for detecting patients with prodromal dementia. Similarities and differences in the NPSs between preclinical/prodromal Alzheimer's disease (AD) and prodromal Parkinson's disease dementia (PDD)/Dementia with Lewy bodies (DLB) may exist. This study aimed to compare the NPSs between preclinical/prodromal AD and prodromal PDD/DLB.

METHODS

One hundred and three participants without dementia aged ≥50 years were included in this study. The mild behavioral impairment (MBI) total score and the MBI scores for each domain were calculated using the neuropsychiatric inventory questionnaire score. Participants were divided into five groups based on the clinical diagnosis by neurologists or psychiatrists in each institution based on the results of the amyloid positron emission tomography and dopamine transporter single photon emission computed tomography (DAT-SPECT): Group 1: amyloid-positive and abnormal DAT-SPECT, Group 2: amyloid-negative and abnormal DAT-SPECT, Group 3: amyloid-positive and normal DAT-SPECT, Group 4: mild cognitive impairment unlikely due to AD with normal DAT-SPECT, and Group 5: cognitively normal with amyloid-negative and normal DAT-SPECT.

RESULTS

The MBI abnormal perception or thought content scores were significantly higher in Group 1 than Group 5 (Bonferroni-corrected p = 0.012). The MBI total score (Bonferroni-corrected p = 0.011) and MBI impulse dyscontrol score (Bonferroni-corrected p = 0.033) in Group 4 were significantly higher than those in Group 5.

CONCLUSION

The presence of both amyloid and putative Lewy body pathologies may be associated with psychotic symptoms.

Continuous partially hydrolyzed guar gum intake reduces cold-like symptoms: a randomized, placebo-controlled, double-blinded trial in healthy adults

OBJECTIVE

Partially hydrolyzed guar gum (PHGG), a water-soluble dietary fiber produced by the controlled partial enzymatic hydrolysis of guar gum beans, has various physiological roles. PHGG is expected to influence the immune function and prevent infections. The objective of this study was to examine the effect of continuous ingestion of PHGG for 12 weeks on the development of cold-like symptoms.

PATIENTS AND METHODS

A placebo-controlled, double blind, randomized, parallel-group comparative study was conducted. 96 healthy Japanese adults received 5.2 g PHGG or placebo daily for 12 weeks. Cold-like symptoms were assessed based on patient diary, and the levels of short-chain fatty acids (SCFAs) in stool and blood immune markers at baseline and at weeks 6 and 12.

RESULTS

The cumulative number of "no symptoms" days for all symptoms was significantly larger in the PHGG than in the placebo group. The result of the analysis by severity of cold-like symptoms also showed significant differences, with the PHGG group having a lower severity of cold-like symptoms. Propionic acid at weeks 6 and 12 and n-butyric acid and total SCFAs at week 12 were significantly higher in the PHGG than in the placebo group. The Interferon-γ level was significantly lower at week 6 in the PHGG than in the placebo group.

CONCLUSIONS

PHGG intake may affect immune function and suppress cold-like symptoms through the production of SCFAs in healthy adults.

Soluble APP-α and APP-β in cerebrospinal fluid as potential biomarkers for differential diagnosis of mild cognitive impairment

OBJECTIVES

Concentrations of soluble amyloid precursor proteins-α (sAPPα) and -β (sAPPβ) in cerebrospinal fluid (CSF) may reflect the neuropathology of Alzheimer's disease (AD). We previously reported that the concentrations of both sAPPα and sAPPβ were significantly higher in patients with mild cognitive impairment (MCI) due to AD (MCI-AD) than in control subjects without cognitive impairment. The present study analyzed whether these sAPPs are useful in the differential diagnosis of MCI.

METHODS

A modified and sensitive method was used to analyze concentrations of sAPPα and sAPPβ in CSF of patients with MCI-AD (n = 30) and MCI due to other causes (MCI-others) (n = 24). Phosphorylated tau (p-tau) and amyloid β-protein 42 (Aβ42) were also analyzed using standard methods.

RESULTS

CSF concentrations of sAPPα and sAPPβ were significantly higher in the MCI-AD than in the MCI-others group (p < 0.001). Furthermore, concentrations of both sAPPα and sAPPβ were highly correlated with the concentration of p-tau, consistent with our previous report.

CONCLUSIONS

Measurement of both sAPPs in CSF using sensitive methods can be helpful in the precise differential diagnosis of patients with MCI.

Predictive scoring method for declining left ventricular ejection fraction in hypertrophic cardiomyopathy

Background

The transition to the dilated phase, as well as sudden cardiac death, is one of the most undesirable scenarios for patients with hypertrophic cardiomyopathy (HCM). Although the dilated phase of HCM (DHCM) is defined as left ventricular ejection fraction (LVEF) &lt;50%, the significance of mildly reduced LVEF is also in the spotlight because this status is considered as a transitional phase of DHCM. Establishing predictive scoring method for declining LVEF is expected.

Methods

Of the 319 HCM patients enrolled in the J-HCM registry from our hospital, we analyzed 168 patients (101 male and 57 female, 63.4±14.8 years), after excluding those who underwent PTSMA, who received pacemaker implantation, and who died or dropped out within 2 years. The patients were divided into two groups according to the change of LVEF from the baseline. During the follow-up period (62.0±109.9 months), LVEF decreased by ≥10% in 37 patients (Group D) whereas it did not in 131 patients (Group C). We compared clinical parameters between the two groups to identify the factors affecting the declining LVEF by ≥10% and examined whether the scoring method using those parameters can predict it.

Results

At the baseline, the percentage of male and diabetic patients was greater in group D than group C (76% vs. 55%, P=0.023 and 38% vs. 12%, P&lt;0.001, respectively). The patients with complete right bundle branch block, wide QRS complex (&gt;100msec), and atrial fibrillation tended to be more in group D than group C (all P&lt;0.1). When the scoring method with those 5 parameters was tested by giving 1 point each, the risk of the declining LVEF was tended to be higher in the patients with 2 or 3 point and significantly higher in those with 4 point compared with that in those with point 0 (OR 2.042, 95% CI 0.983–4.243, P=0.056 and OR 12.000, 95% CI 2.313–62.267, P=0.003, respectively).

Conclusions

This scoring method appeared to be useful to stratify the risk of the decrease in LVEF in patients with HCM. The validation study is warranted in a larger population.

Funding Acknowledgement

Type of funding sources: None.

Effects of multisession transcranial direct current stimulation as an augmentation to cognitive tasks in patients with neurocognitive disorders in Japan: a study protocol for a randomised controlled trial

INTRODUCTION

Transcranial direct current stimulation (tDCS) is a potentially novel strategy for cognitive enhancement in patients with disorders. We present a study protocol for a randomised controlled trial designed to evaluate the safety and efficacy of tDCS combined with cognitive tasks on cognition in such patients.

METHOD AND ANALYSIS

This is a two-arm, parallel-design, randomised, sham-controlled trial, in which participants and raters will be blinded at a single centre. Stratified randomisation will be conducted, and a randomisation sequence will be generated through the Electronic Data Capture system. Patients who met the Diagnostic and Statistical Manual of Mental Disorders-5 criteria for neurocognitive disorders will be recruited and randomised to receive either active (2 mA for 20 min) or sham (stimulation ramped up and down for 1 min) stimulation in 10 sessions over five consecutive days. A direct current will be transferred by a 35 cm² saline-soaked sponge electrode. An anode will be placed over the left dorsolateral prefrontal cortex, and a cathode will be placed over the right supraorbital cortex. Calculation tasks will be conducted in both arms as a cognitive task for 20 min during the stimulation. This task consists of basic arithmetic questions, such as single-digit addition, subtraction, multiplication and division. The primary outcome will be the mean change in the Alzheimer Disease Assessment Scale-cognition at Day 5 after baseline. Depressive symptoms, as measured by the geriatric depression scale, and quality of life, as measured by the Medical Outcomes Study 36-item Short-Form Health Survey, will also be assessed. Data will be collected at baseline, within 3 days following the final stimulation and 1 month thereafter. The estimated sample size is 46 per group based on the assumptions that an estimated mean difference is -1.61 and SD is 2.7. Mixed models for repeated measures will be used for the statistical analysis.

ETHICS AND DISSEMINATION

The National Center of Neurology and the Psychiatry Clinical Research Review Board (CRB3180006) approved this study. The results of this study will be published in a scientific peer-reviewed journal.

TRIAL REGISTRATION DETAILS

Japan Registry of Clinical Trials jRCTs032180016.

Differential associations of dopamine synthesis capacity with the dopamine transporter and D2 receptor availability as assessed by PET in the living human brain

BACKGROUND

The dopamine (DA) neurotransmission has been implicated in fundamental brain functions, exemplified by movement controls, reward-seeking, motivation, and cognition. Although dysregulation of DA neurotransmission in the striatum is known to be involved in diverse neuropsychiatric disorders, it is yet to be clarified whether components of the DA transmission, such as synthesis, receptors, and reuptake are coupled with each other to homeostatically maintain the DA neurotransmission. The purpose of this study was to investigate associations of the DA synthesis capacity with the availabilities of DA transporters and D2 receptors in the striatum of healthy subjects.

METHODS

First, we examined correlations between the DA synthesis capacity and DA transporter availability in the caudate and putamen using PET data with L-[β-¹¹C]DOPA and [¹⁸F]FE-PE2I, respectively, acquired from our past dual-tracer studies. Next, we investigated relationships between the DA synthesis capacity and D2 receptor availability employing PET data with L-[β-¹¹C]DOPA and [¹¹C]raclopride, respectively, obtained from other previous dual-tracer assays.

RESULTS

We found a significant positive correlation between the DA synthesis capacity and DA transporter availability in the putamen, while no significant correlations between the DA synthesis capacity and D2 receptor availability in the striatum.

CONCLUSION

The intimate association of the DA synthesis rate with the presynaptic reuptake of DA indicates homeostatic maintenance of the baseline synaptic DA concentration. In contrast, the total abundance of D2 receptors, which consist of presynaptic autoreceptors and postsynaptic modulatory receptors, may not have an immediate relationship to this regulatory mechanism.

Association between neurite metrics and tau/inflammatory pathology in Alzheimer's disease

INTRODUCTION

The molecular mechanism of neurodegeneration, including tau and neurite complexity, is an important topic in Alzheimer's disease (AD) research.

METHODS

We recruited 27 amyloid-positive individuals identified through 11C-Pittsburgh compound B (PiB) positron emission tomography (PET) and 31 amyloid-negative individuals with normal cognition. All participants underwent 11C-PiB and 18F-THK5351 PET and magnetic resonance imaging (MRI) with neurite orientation dispersion and density imaging (NODDI) protocol. The neurite density index (NDI), orientation dispersion index (ODI), and PET images were analyzed to calculate voxel-wise correlations among the imaging modalities and correlations with cognitions.

RESULTS

In the amyloid-positive participants, there were significant negative correlations between 18F-THK5351 and NDI and between 18F-THK5351 and ODI. The bilateral mesial and lateral temporal lobes were mainly involved. Regarding cognition, 18F-THK5351 showed more marked associations with all cognitive domains than the other modalities.

DISCUSSION

Tau and neuroinflammation in AD may reduce the neurite density and orientation dispersion, particularly in the mesial and lateral temporal lobes.

Effect of empagliflozin versus placebo on body composition in patients with acute myocardial infarction and type 2 diabetes mellitus: subgroup analysis of the EMBODY trial

Background

Prevention of heart failure is one of the most important challenges after acute myocardial infarction (AMI). The development of heart failure is closely associated with fluid balance which can be evaluated by the measurement of body composition such as total body water (TBW), extracellular water (ECW), and intracellular water (ICW). This subgroup analysis of the EMBODY trial was designed to determine whether the Sodium–glucose cotransporter 2 (SGLT2) inhibitor affect fluid balance and improve heart failure in patients after AMI.

Methods

The EMBODY trial was a prospective, multicenter, randomized, double-blind, placebo-controlled trial in patients with AMI and type 2 diabetes in Japan. A total of 105 patients were randomized (1:1) to receive once-daily 10 mg empagliflozin, an SGLT2 inhibitor or placebo 2 weeks after the onset of AMI. In this subanalysis, we investigated the time-course of body composition measured by a bioelectrical impedance analyzer “InBody®”. The primary endpoints were changes in every particular parameter of body composition at week 0, 4, 12, and 24. Secondary endpoints were changes in blood pressure (BP), body weight and N-terminal pro b-type natriuretic peptide (NT-proBNP).

Results

Overall, 55 patients were included in the full analysis set (67.2±10.0 years, male 78.2%, and n=30 in empagliflozin group and 25 in placebo group). Baseline characteristics were not significantly different between the two groups. The change between at baseline and 24 weeks in TBW was −0.44 L (P=0.19) in the empagliflozin group and +1.14 L (P=0.0002) in the placebo group, adjusted difference −1.58 L, 95% confidence interval (CI) −2.46 to −0.70 L (P=0.0006). The empagliflozin group showed significant decreases in the body weight, ECW, ICW and systolic BP compared with the placebo group (−2.2 kg vs, +0.01 kg, P=0.004, −0.21 L vs, +0.40 L, P=0.001, −0.23 L vs, +0.74 L, P=0.0007, and −11.0 mmHg vs, +5.0 mmHg, P&lt;0.0001, respectively). On the other hand, NT-Pro BNP levels significantly decreased in the empagliflozin group and placebo group (1028.7 pg/mL to 370.3 pg/ml, p=0.0001 and 1270.6 pg/mL to 673.7 pg/ml, p=0.006, respectively). In the multiple regression analysis of the change in TBW and ICW for the empagliflozin group, systolic BP was identified as a significant factor (P=0.001, and 0.003, respectively). In stratified analysis of BMI 25 kg/m2 or more, the empagliflozin group showed significant decreases in body weight, TBW, ECW and ICW compared with the placebo group, but not below BMI 25 kg/m2 group.

Conclusion

Empagliflozin reduced not only body weight, but also TBW, ECW and ICW. Interestingly, this tendency was remarkable at BMI 25 or more. This study suggested that early SGLT2 inhibitor administration in obesity patients with AMI and DM might be effective to reduce body weight and TBW.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Boehringer Ingelheim

Baseline clinical features in a large-scale registration survey of patient with hypertrophic cardiomyopathy throughout Japan: J-HCM registry study

Background

Hypertrophic cardiomyopathy (HCM) is a most prevalent primary myocardial disorder with heterogeneous clinical features. However, there have been few studies on clinical features of HCM as a prospective cohort. In 2015, we established a large-scale registration survey of patients with HCM throughout Japan, named J-HCM registry study.

Purpose

The aim of this study was to clarify the clinical features of Japanese patients with HCM.

Methods

J-HCM registry study is a prospective, multicenter investigation, consisting of 24 hospitals. This time, we present the baseline clinical characteristics in this survey.

Results

Total 1484 patients were registered. The ages at registration and at diagnosis were 65±15 and 56±17 years, respectively, and 806 patients (54%) were men. Majority of the patients (95%) was NYHA class I or II. With regard to subtypes of HCM, there were 526 patients (36%) in the HCM with left ventricular (LV) outflow tract obstruction, 126 patients (8%) in the mid-ventricular obstruction, 57 patients (4%) in the end-stage phase characterized by LV ejection fraction &lt;50%, and 197 patients (14%) in apical HCM. At registration, 80 patients (6%) had prior successful recovery from sustained ventricular tachycardia or ventricular fibrillation, 162 patients (11%) suffered from heart failure hospitalization, and 64 patients (4%) had history of embolic event. Regarding invasive treatment, 160 patients (10%) had prior septal reduction therapy and 162 patients (11%) had ICD implantation. According to the 2014 European Society of Cardiology Guidelines on sudden cardiac death (SCD) prevention, the study patients were divided into 3 categories by the HCM Risk-SCD calculator: patients distribution, 4% in the high risk group (≥6% calculated HCM Risk-SCD at 5 years), 7% in the intermediate risk group (4% to &lt;6%), 69% in the low risk group (&lt;4%), and 16% in the patients with extreme characteristics (Figure 1).

Conclusions

In this multicenter registration survey of patients with HCM, the baseline clinical characteristics were almost similar to several retrospective large-scale cohorts in Western countries except older age and less symptomatic state. This study will provide important knowledge regarding management of HCM.

Figure 1

Funding Acknowledgement

Type of funding source: None

Discrete effect of each mild behavioural impairment category on dementia conversion or cognitive decline in patients with mild cognitive impairment

BACKGROUND

Neuropsychiatric symptoms (NPS) have been recognized as risk factors for conversion to dementia in patients with mild cognitive impairment (MCI). Early detection of NPS may allow for possible interventions in such patients. The present study used mild behavioural impairment to explore the role of NPS in a wide range of patients, from those who are cognitively intact to those with dementia.

METHODS

A total of 234 patients with mild cognitive impairment were followed up for up to 3 years in a Japanese cohort study. Longitudinal data from patients who developed dementia during the study and those who did not were statistically analyzed.

RESULTS

Cox regression analysis revealed that only abnormal perception and thought was significant in terms of dementia conversion. Moreover, mixed-effects models indicated that baseline mild behavioural impairment symptoms did not affect cognitive trajectories such as changes in Mini-Mental State Examination or Alzheimer's Disease Assessment Scale-cognitive subscale scores.

CONCLUSION

We conclude that only abnormal perception and thought content were risk factors for dementia and that NPS may not lead to deterioration of cognitive function in patients with mild cognitive impairment.

P889Clinical significance of four-dimensional flow magnetic resonance imaging measurement of turbulent kinetic energy for hypertrophic obstructive cardiomyopathy

Purpose

The aims of this study were to investigate the relationship between TKE value and echocardiographic findings, clinical symptoms and evaluate the usefulness of 4D flow MRI to distinguish hypertrophic obstructive cardiomyopathy (HOCM) from non-obstructive HCM (HNCM).

Methods

From April 2018 to January 2019, 18 hypertrophic obstructive cardiomyopathy (HOCM) and 14 non-obstructive HCM (HNCM) patients underwent 4D flow MRI. We investigated TKE value calculated by 4D flow MRI, echocardiographic findings; left ventricular pressure gradient (LVPG), mitral regurgitation (MR) and clinical symptom.

Results

HOCM was defined by the 30 mmHg or greater of LVPG (HOCM: 87.7±47.3 mmHg, HNCM; 5.8±7.8 mmHg, p<0.001). TKE value in HOCM patients was significantly higher than HNCM (14.2±4.7 mJ vs. 9.0±4.6 mJ, p<0.001). There was a significant positive linear relationship between TKE value and LVPG (r=0.488, p=0.046). There was no significant relationship between NYHA functional class and TKE value (p=0.47) or LVPG (p=0.11). ROC curve analysis showed that optimal cut off point of TKE value between HOCM and HNCM (sensitivity=95%, specificity=62%, AUC=0.798) was 9.270 mJ. Multiple linear regression showed that there was significant association between severity of MR and combination of TKE (p=0.015) or LVPG (p–=0.012). A representative case demonstrated the significant reduction of TKE value 1 week and 3 months after alcohol septal reduction compared with that obtained before the procedure (Figure)

Conclusion

Our findings suggest that 4D Flow MRI can effectively evaluate the energy dissipation associated with LV outflow tract obstruction and TKE value is useful for identifying HOCM. TKE value also can be the novel parameter of the severity of HOCM.

Voxel-based correlation of 18F-THK5351 accumulation and gray matter volume in the brain of cognitively normal older adults

Backgrounds

Although neurofibrillary tangles (NFTs) mainly accumulate in the medial temporal lobe with human aging, only a few imaging studies have investigated correlations between NFT accumulation and gray matter (GM) volume in cognitively normal older adults. Here, we investigated the correlations between ¹⁸F-THK5351 accumulation and GM volume at the voxel level.

Material and methods

We recruited 47 amyloid-negative, cognitively normal, older adults (65.0 ± 7.9 years, 26 women), who underwent structural magnetic resonance imaging, ¹¹C-Pittsburgh compound-B and ¹⁸F-THK5351 PET scans, and neuropsychological assessment. The magnetic resonance and ¹⁸F-THK5351 PET images were spatially normalized using Statistical Parametric Mapping 12. Voxel-wise correlations between ¹⁸F-THK5351 accumulation and GM volume were evaluated using the Biological Parametric Mapping toolbox.

Results

A significant negative correlation (p < 0.001) between ¹⁸F-THK5351 accumulation and GM volume was detected in the bilateral medial temporal lobes.

Conclusions

Voxel-wise correlation analysis revealed a significant negative correlation between ¹⁸F-THK5351 accumulation and GM volume in the medial temporal lobe in individuals without amyloid-β deposits. These results may contribute to a better understanding of the pathophysiology of primary age-related tauopathy in human aging.

Association between subfield volumes of the medial temporal lobe and cognitive assessments

Cognitive assessments and neuroimaging are routinely combined in clinical practice to diagnose dementia represented by Alzheimer's disease (AD). The Montreal Cognitive Assessment (MoCA) is reported to be more suitable than the Mini-Mental State Examination (MMSE) for screening mild cognitive impairment (MCI) and mild AD. On the other hand, attention to the subfield volumes of the medial temporal lobe has recently been considered important for the differential diagnosis and early detection of AD. The aim of this study was to uncover which specific hippocampal subfields and adjacent extrahippocampal structures contribute to deficits in cognitive assessment scores in patients with MCI and AD. We recruited from our institute 31 Japanese patients—14 with amnestic MCI and 17 with probable AD, with a clinical dementia rating (CDR) of 0.5 and 1, respectively—and 50 healthy elderly individuals with a CDR of 0. All participants underwent magnetic resonance imaging and cognitive assessments with the MMSE, Wechsler Memory Scale-Revised Logical Memory I and II, and Japanese version of the MoCA (MoCA-J). With adjustment for age and sex, we performed partial correlation analysis of the cognitive assessment scores with the subfield volumes of the medial temporal lobe measured by software-mediated automatic segmentation of hippocampal subfields using high-resolution T1-and T2-weighted images. Compared with normal controls, patients with MCI and AD showed subfield volume reductions in cornu ammonis (CA) 1, CA2, Brodmann area (BA) 35, BA36, the dentate gyrus (DG), the subiculum, and the entorhinal cortex (ERC). All participants showed high correlation coefficients (above 0.6) between cognitive assessment scores and subfield volumes in CA1, the DG, the subiculum, the ERC, and BA36. In patients with MCI and AD, the MoCA-J showed higher correlations than the MMSE with subfield volumes in CA1, the DG, the subiculum, and the ERC. These results suggest that the combination of the in vivo analysis of subfield morphometry of the medial temporal lobe with the MoCA-J paradigm provides important insights into whether changes within specific subfields are related to the cognitive profile in MCI and AD.

Blister beetle dermatitis caused by cantharidin in South Sudan in Op TRENTON: a case series

Cantharidin-producing blister beetles are found worldwide. The pathognomonic feature of their toxin is a blistering dermatitis that presents an environmental health hazard. Cutaneous exposure to cantharidin can produce blistering dermatitis, most commonly seen on exposed skin, in the Bentiu region of South Sudan. This should be treated with appropriate cleaning, debridement and regular dressing changes to cope with extensive initial exudate. The best dressing combinations found were initial treatment with povidone-iodine and hydrocolloid, followed by hydrocolloid only. Hydrocolloid dressings were found to be the most effective at staying in place with South Sudan's high humidity. Prevention strategies should include covering exposed skin, wearing wide-brimmed hats, neck scarves and enclosed footwear, and avoidance of working under white light. Medical personnel should engage with the chain of command to include appropriate force protection education within the arrivals brief.

Pisa syndrome associated with mirtazapine: a case report

Background

Mirtazapine is a noradrenergic and specific serotonergic antidepressant; its pharmacological profile indicates a low risk for dopaminergic adverse effects. To date, there has been only a single case report of Pisa syndrome associated with mirtazapine.

Case presentation

The authors report a case involving a 79-year-old woman with bipolar disorder, in whom Pisa syndrome occurred after introduction of mirtazapine, and completely disappeared 3 days after suspension of the drug.

Conclusions

Aspects of this particular case suggest that Pisa syndrome is a possible side effect of Mirtazapine.

Association of deposition of tau and amyloid-β proteins with structural connectivity changes in cognitively normal older adults and Alzheimer's disease spectrum patients

INTRODUCTION

Alzheimer's disease (AD) is characterized by accumulation of extracellular amyloid-β and intracellular tau neurofibrillary tangles. The recent advent of tau positron emission tomography (PET) has enabled in vivo assessment of tau pathology. The aim of this study was to explore whether tau deposition influences the structural connectivity in amyloid-negative and amyloid-positive groups, and further explore the difference between the groups.

METHODS

We investigated 18 patients with amnestic mild cognitive impairment/mild AD (AD-spectrum group) and 35 cognitively normal older adults (CN group) using diffusion MRI, amyloid, and tau PET imaging. Diffusion connectometry was performed to identify white matter pathways correlated with each of the six variables of tau deposition in the bilateral hippocampi, temporal lobes, posterior and anterior cingulate cortices, precunei, orbitofrontal lobes, and entire cerebrum.

RESULTS

The CN group showed increased connectivity along with an increased tau deposition in the bilateral hippocampi, temporal lobes, and entire cerebrum, whereas the AD-spectrum group showed decreased connectivity in the bilateral hippocampi, temporal lobes, anterior and posterior cingulate cortices, precunei, and entire cerebrum.

CONCLUSION

These findings suggest that tau deposition in the CN group seems to induce a compensatory response against early neuronal injury or chronic inflammation associated with normal aging, whereas the coexistence of amyloid and tau in the AD-spectrum group seems to outweigh the compensatory response leading to decreased connectivity, suggesting that amyloid plays a crucial role in alternating structural connectivity.

Effects of a medium-chain triglyceride-based ketogenic formula on cognitive function in patients with mild-to-moderate Alzheimer's disease

Clinical and animal studies suggested that a medium-chain triglyceride (MCT)-based ketogenic diet provides an alternative energy substrate to the brain and has neuroprotective effects, but the clinical evidence is still scarce. Here we examined the effect of an MCT-based ketogenic formula on cognitive function in patients with Alzheimer's disease (AD). The subjects were 20 Japanese patients with mild-to-moderate AD (11 males, nine females, mean age 73.4 ± 6.0 years) who, on separate days, underwent neurocognitive tests 120 min after consuming 50 g of a ketogenic formula (Ketonformula^®) containing 20 g of MCTs or an isocaloric placebo formula without MCTs. The patients then took 50 g of the ketogenic formula daily for up to 12 weeks, and underwent neurocognitive tests monthly. In the first trial, although the patients' plasma levels of ketone bodies were successfully increased 120 min after the single intake of the ketogenic formula, there was no significant difference in any cognitive test results between the administrations of the ketogenic and placebo formulae. In the subsequent chronic intake trial of the ketogenic formula, 16 of the 20 patients completed the 12-week regimen. At 8 weeks after the trial's start, the patients showed significant improvement in their immediate and delayed logical memory tests compared to their baseline scores, and at 12 weeks they showed significant improvements in the digit-symbol coding test and immediate logical memory test compared to the baseline. The chronic consumption of the ketogenic formula was therefore suggested to have positive effects on verbal memory and processing speed in patients with AD.

Possible effects of electroconvulsive therapy on refractory psychosis in primary progressive multiple sclerosis: A case report

Introduction

Patients with multiple sclerosis commonly show some degree of psychiatric symptoms. Primary progressive multiple sclerosis is a part of the spectrum of multiple sclerosis phenotypes with progressive accumulation of disability from disease onset and active course. Psychiatric symptoms are commonly shown in multiple sclerosis, and up to 10% of patients with multiple sclerosis have the primary progressive form. Thus, patients with primary progressive multiple sclerosis may also elicit psychiatric symptoms. However, little information is available on psychiatric symptoms, especially on psychosis, in primary progressive multiple sclerosis.

Case

Here, we report on a 42‐year‐old woman with primary progressive multiple sclerosis whose psychosis did not respond to antipsychotics and was partially ameliorated by electroconvulsive therapy. She suffered from auditory hallucination, anxiety, depersonalization, and suicidal ideation. Initially, several antipsychotic agents were tried, but not effective. Given this, she underwent 12 sessions of electroconvulsive therapy.

Conclusion

Our observation suggests the possible utility of electroconvulsive therapy in the treatment of psychosis in primary progressive multiple sclerosis.

Dissociation of Tau Deposits and Brain Atrophy in Early Alzheimer's Disease: A Combined Positron Emission Tomography/Magnetic Resonance Imaging Study

The recent advent of tau-specific positron emission tomography (PET) has enabled in vivo assessment of tau pathology in Alzheimer’s disease (AD). However, because PET scanners have limited spatial resolution, the measured signals of small brain structures or atrophied areas are underestimated by partial volume effects (PVEs). The aim of this study was to determine whether partial volume correction (PVC) improves the precision of measures of tau deposits in early AD. We investigated tau deposits in 18 patients with amyloid-positive early AD and in 36 amyloid-negative healthy controls using ¹⁸F-THK5351 PET. For PVC, we applied the SPM toolbox PETPVE12. The PET images were then spatially normalized and subjected to voxel-based group analysis using SPM12 for comparison between the early AD patients and healthy controls. We also compared these two groups in terms of brain atrophy using voxel-based morphometry of MRI. We found widespread neocortical tracer retention predominantly in the posterior cingulate and precuneus areas, but also in the inferior temporal lobes, inferior parietal lobes, frontal lobes, and occipital lobes in the AD patients compared with the controls. The pattern of tracer retention was similar between before and after PVC, suggesting that PVC had little effect on the precision of tau load measures. Gray matter atrophy was detected in the medial/lateral temporal lobes and basal frontal lobes in the AD patients. Interestingly, only a few associations were found between atrophy and tau deposits, even after PVC. In conclusion, PVC did not significantly affect ¹⁸F-THK5351 PET measures of tau deposits. This discrepancy between tau deposits and atrophy suggests that tau load precedes atrophy.

Neuromolecular basis of faded perception associated with unreality experience

Perceptual changes in shape, size, or color are observed in patients with derealization symptoms; however, the underlying neural and molecular mechanisms are not well understood. The current study explored the relationship between neural activity associated with altered colorfulness perception assessed by fMRI and striatal dopamine D₂ receptor availability measured by [¹¹C]raclopride PET in healthy participants. Inside an fMRI scanner, participants performed the saturation adaptation task, where they rated how much vivid/faded visual objects looked like real/unreal ones using a visual analog scale. We found that participants experienced greater unreality when they perceived fadedness than vividness despite physically identical saturation. The combined fMRI and PET analyses revealed that the faded perception-related activities of the dorsolateral prefrontal and parietal cortex were positively correlated with striatal D₂ receptor availability. This finding may help to understand the neuromolecular mechanisms of faded perception associated with feeling unreal in derealization symptoms.

Prerequisites to Salvage Profound Biventricular Failure Patients with Ventricular Assist Devices

We conducted chronic experiments to determine how to treat profound biventricular failure systematically with ventricular assist devices (VADs) and to analyze the factors that affect prognoses for this condition. Anoxic arrest was induced in ten goats by aortic cross-clamping under normothermic conditions (38.5° C) for 30 (n= 3), 45 (n= 1), and 60 (n= 6) minutes. A left ventricular assist device (LVAD) was implanted in eight animals, and a biventricular assist device (BVAD) was used in two. Three goats — two of which had undergone anoxic arrest for 30 minutes and one for 60 minutes — whose right atrial pressure (RAP) was approximately 18 mm Hg during the acute stage, recovered in two to three weeks, and the pumps were successfully removed. Pathological findings in these animals showed scattered areas of surviving myocardium, with connective tissue replacing the degenerated myocardium. The remaining five LVAD goats required higher RAPs to maintain circulation and died from various causes. Maintaining circulation without volume loading, even in the presence of arrhythmias, was easier with the BVAD. One BVAD animal that underwent 45 minutes of anoxic arrest recovered from right ventricular failure, and the right pump was removed. The second goat (anoxic arrest, 60 min) on the BVAD failed to recover. Autopsy of the myocardium revealed a thin ventricular wall. Our studies show that the use of VADs allows time for a failing heart to recover, but the potential for healing is affected by the severity of myocardial damage prior to VAD application. We believe that although LVADs can maintain circulation with high RAPs, the use of BVADs might be more beneficial for maintaining systemic organ function in cases of persistent biventricular failure.

Treatment of Acute Myocardial Infarction with Cardiogenic Shock using Left Ventricular Assist Device

We have treated ten cardiogenic shock patients after acute myocardial infarction (AMI) with a left ventricular assist device (LVAD). These patients were later divided into three groups: the first group with ventricular septal perforation, the second with aorto-coronary bypass grafting (ACBG) before LVAD implantation and the third group without ACBG. LVAD maintained the systemic circulation in each group, and cardiac function recovered enough to remove LVAD in 70% of the total patients. Two of three patients in the first group were discharged from hospital. Two weaned cases in the second group died of multiple organ failure and one was discharged, and hemorrhagic necrosis was seen in the bypassed area of the myocardium. One patient of the third group could not be weaned from LVAD because of respiratory failure though his heart function began to recover. Another case in the third group underwent bypass grafting after removal of LVAD. However ACBG surgery should be done very carefully because a patient in shock is occasionally intolerant to major surgery. In all groups, the major cause of death was multiple organ failure which was probably caused by the prolonged low output condition prior to LVAD application. In the light of this experience, it appears that LVAD should be applied before irreversible damage occurs to major organs, including the heart itself. To ensure the timely application of LVAD, some way must be found to introduce systematic application of LVAD into the normal course of AMI treatment.

Prolonged Nonpulsatile Left Heart Bypass Diminishes Vascular Contractility

We investigated possible functional changes in the vascular system accompanying the morphological change in prolonged nonpulsatile left heart bypass (LHB). Three adult goats underwent pulsatile LHB. Two weeks postoperatively, the pulsatile ventricular assist device was replaced with a centrifugal pump and nonpulsatile LHB was subsequently conducted for 4 weeks. The mean aortic pulse pressure was 39 and 16 mmHg during the pulsatile and nonpulsatile LHB, respectively. Systemic vascular resistance (SVR) and plasma norepinephrine levels were measured at the end of pulsatile LHB (PUL), and at the end of 1st, 2nd, 3rd, and 4th week of nonpulsatile LHB (NP1w, NP2w, NP3w, NP4w, respectively). At each point, 50 μg/kg nitroglycerin and 1μg/kg norepinephrine were injected and the minimal and maximal values of SVR after injection were calculated as parameters reflecting the vascular tonus and contractility. The SVR and plasma nor epinephrine level did not significantly change during the entire course (SVR: 1106, 895, 982, 920, and 938 dyne·sec·cm−5; norepinephrine level: 0.3, 0.2, 0.1, 0.2, and 0.1 ng/ml; at PUL, NP1w, NP2w, NP3w, and NP4w, respectively). The minimal value of SVR after nitroglycerin injection remained unchanged, indicating that vascular tonus was stable during the entire course (618, 687, 623, 560, 653 dyne·sec·cm−5, respectively). In contrast, the maximal value of SVR after norepinephrine injection at NP3w and NP4w (1695 and 1759 yne·sec·cm−5) became significantly reduced compared to that at PUL (2346 dyne·sec·cm−5). These results indicated that prolonged nonpulsatile left heart bypass did not affect the vascular tonus, but significantly diminished the vascular contractility.

Japanese multicenter database of healthy controls for [123I]FP-CIT SPECT

PURPOSE

The aim of this multicenter trial was to generate a [¹²³I]FP-CIT SPECT database of healthy controls from the common SPECT systems available in Japan.

METHODS

This study included 510 sets of SPECT data from 256 healthy controls (116 men and 140 women; age range, 30-83 years) acquired from eight different centers. Images were reconstructed without attenuation or scatter correction (NOACNOSC), with only attenuation correction using the Chang method (ChangACNOSC) or X-ray CT (CTACNOSC), and with both scatter and attenuation correction using the Chang method (ChangACSC) or X-ray CT (CTACSC). These SPECT images were analyzed using the Southampton method. The outcome measure was the specific binding ratio (SBR) in the striatum. These striatal SBRs were calibrated from prior experiments using a striatal phantom.

RESULTS

The original SBRs gradually decreased in the order of ChangACSC, CTACSC, ChangACNOSC, CTACNOSC, and NOACNOSC. The SBRs for NOACNOSC were 46% lower than those for ChangACSC. In contrast, the calibrated SBRs were almost equal under no scatter correction (NOSC) conditions. A significant effect of age was found, with an SBR decline rate of 6.3% per decade. In the 30-39 age group, SBRs were 12.2% higher in women than in men, but this increase declined with age and was absent in the 70-79 age group.

CONCLUSIONS

This study provided a large-scale quantitative database of [¹²³I]FP-CIT SPECT scans from different scanners in healthy controls across a wide age range and with balanced sex representation. The phantom calibration effectively harmonizes SPECT data from different SPECT systems under NOSC conditions. The data collected in this study may serve as a reference database.

Two-step relaxation mode analysis with multiple evolution times applied to all-atom molecular dynamics protein simulation

Proteins implement their functionalities when folded into specific three-dimensional structures, and their functions are related to the protein structures and dynamics. Previously, we applied a relaxation mode analysis (RMA) method to protein systems; this method approximately estimates the slow relaxation modes and times via simulation and enables investigation of the dynamic properties underlying the protein structural fluctuations. Recently, two-step RMA with multiple evolution times has been proposed and applied to a slightly complex homopolymer system, i.e., a single [n]polycatenane. This method can be applied to more complex heteropolymer systems, i.e., protein systems, to estimate the relaxation modes and times more accurately. In two-step RMA, we first perform RMA and obtain rough estimates of the relaxation modes and times. Then, we apply RMA with multiple evolution times to a small number of the slowest relaxation modes obtained in the previous calculation. Herein, we apply this method to the results of principal component analysis (PCA). First, PCA is applied to a 2-μs molecular dynamics simulation of hen egg-white lysozyme in aqueous solution. Then, the two-step RMA method with multiple evolution times is applied to the obtained principal components. The slow relaxation modes and corresponding relaxation times for the principal components are much improved by the second RMA.

Cognitive Function and Monoamine Neurotransmission in Schizophrenia: Evidence From Positron Emission Tomography Studies

Positron emission tomography (PET) is a non-invasive imaging technique used to assess various brain functions, including cerebral blood flow, glucose metabolism, and neurotransmission, in the living human brain. In particular, neurotransmission mediated by the monoamine neurotransmitters dopamine, serotonin, and norepinephrine, has been extensively examined using PET probes, which specifically bind to the monoamine receptors and transporters. This useful tool has revealed the pathophysiology of various psychiatric disorders, including schizophrenia, and the mechanisms of action of psychotropic drugs. Because monoamines are implicated in various cognitive processes such as memory and executive functions, some PET studies have directly investigated the associations between monoamine neurotransmission and cognitive functions in healthy individuals and patients with psychiatric disorders. In this mini review, I discuss the findings of PET studies that investigated monoamine neurotransmission under resting conditions, specifically focusing on cognitive functions in patients with schizophrenia. With regard to the dopaminergic system, some studies have examined the association of dopamine D1 and D2/D3 receptors, dopamine transporters, and dopamine synthesis capacity with various cognitive functions in schizophrenia. With regard to the serotonergic system, 5-HT1A and 5-HT2A receptors have been studied in the context of cognitive functions in schizophrenia. Although relatively few PET studies have examined cognitive functions in patients with psychiatric disorders, these approaches can provide useful information on enhancing cognitive functions by administering drugs that modulate monoamine transmission. Moreover, another paradigm of techniques such as those exploring the release of neurotransmitters and further development of radiotracers for novel targets are warranted.

Re-evaluation of soluble APP-α and APP-β in cerebrospinal fluid as potential biomarkers for early diagnosis of dementia disorders

Background

Because soluble (or secreted) amyloid precursor protein-β (sAPPβ) and -α (sAPPα) possibly reflect pathological features of Alzheimer’s disease (AD), they are potential biomarker candidates for dementia disorders, including AD and mild cognitive impairment (MCI) due to AD (MCI-AD). However, controversial results have been reported regarding their alterations in the cerebrospinal fluid (CSF) of AD and MCI-AD patients. In this study, we re-assessed the utility of sAPPα and sAPPβ in CSF as diagnostic biomarkers of dementia disorders.

Methods

We used a modified and sensitive detection method to analyze sAPPs levels in CSF in four groups of patients: AD (N = 33), MCI-AD (N = 17), non-AD dementia (N = 27), and disease controls (N = 19). Phosphorylated tau (p-tau), total tau, and Aβ42 were also analyzed using standard methods.

Results

A strong correlation was observed between sAPPα and sAPPβ, consistent with previous reports. Both sAPPα and sAPPβ were highly correlated with p-tau and total tau, suggesting that sAPPs possibly reflect neuropathological changes in the brain. Levels of sAPPα were significantly higher in MCI-AD cases compared with non-AD and disease control cases, and those of sAPPβ were also significantly higher in MCI-AD and AD cases relative to other cases. A logistic regression analysis indicated that sAPPα and sAPPβ have good discriminative power for the diagnosis of MCI-AD.

Conclusions

Our findings collectively suggest that both sAPPs are pathologically relevant and potentially useful biomarkers for early and accurate diagnosis of dementia disorders. We also suggest that careful measurement is important in assessing the diagnostic utility of CSF sAPPs.

Electronic supplementary material

The online version of this article (10.1186/s40364-017-0108-5) contains supplementary material, which is available to authorized users.

Regional tau deposition and subregion atrophy of medial temporal structures in early Alzheimer's disease: A combined positron emission tomography/magnetic resonance imaging study

Introduction

Molecular imaging and selective hippocampal subfield atrophy are a focus of recent Alzheimer's disease (AD) research. Here, we investigated correlations between molecular imaging and hippocampal subfields in early AD.

Methods

We investigated 18 patients with early AD and 18 healthy control subjects using ¹¹C-Pittsburgh compound-B (PIB) positron emission tomography (PET) and ¹⁸F-THK5351 PET and automatic segmentation of hippocampal subfields with high-resolution T2-weighted magnetic resonance imaging. The PET images were normalized and underwent voxelwise regression analysis with each subregion volumes using SPM12.

Results

As for ¹⁸F-THK5351 PET, the bilateral perirhinal cortex volumes were significantly associated with the ipsilateral or bilateral temporal lobar uptakes, whereas hippocampal subfields showed no correlations. ¹¹C-PIB PET showed relatively broad negative correlation with the right cornu ammonis 3 volumes.

Discussion

Regional tau deposition was correlated with extrahippocampal subregional atrophy and not with hippocampal subfields, possibly reflecting different underlying mechanisms of atrophy in early AD. Amyloid might be associated with right cornu ammonis 3 atrophy.

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Molecular imaging and hippocampal subfield are hot topics of Alzheimer's disease.

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We investigated 18 patients with early Alzheimer's disease by amyloid/tau imaging.

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Bilateral perirhinal cortices were significantly correlated with tau deposition.

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Hippocampal subfields showed no significant correlations with tau deposition.

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Amyloid deposition showed a correlation with right CA3 volumes.

Occupancy of Norepinephrine Transporter by Duloxetine in Human Brains Measured by Positron Emission Tomography with (S,S)-[18F]FMeNER-D2

BACKGROUND

The norepinephrine transporter in the brain has been targeted in the treatment of psychiatric disorders. Duloxetine is a serotonin and norepinephrine reuptake inhibitor that has been widely used for the treatment of depression. However, the relationship between dose and plasma concentration of duloxetine and norepinephrine transporter occupancy in the human brain has not been determined. In this study, we examined norepinephrine transporter occupancy by different doses of duloxetine.

METHODS

We calculated norepinephrine transporter occupancies from 2 positron emission tomography scans using (S,S)-[18F]FMeNER-D2 before and after a single oral dose of duloxetine (20 mg, n = 3; 40 mg, n = 3; 60 mg, n =2). Positron emission tomography scans were performed from 120 to 180 minutes after an i.v. bolus injection of (S,S)-[18F]FMeNER-D2. Venous blood samples were taken to measure the plasma concentration of duloxetine just before and after the second positron emission tomography scan.

RESULTS

Norepinephrine transporter occupancy by duloxetine was 29.7% at 20 mg, 30.5% at 40 mg, and 40.0% at 60 mg. The estimated dose of duloxetine inducing 50% norepinephrine transporter occupancy was 76.8 mg, and the estimated plasma drug concentration inducing 50% norepinephrine transporter occupancy was 58.0 ng/mL.

CONCLUSIONS

Norepinephrine transporter occupancy by clinical doses of duloxetine was approximately 30% to 40% in human brain as estimated using positron emission tomography with (S,S)-[18F]FMeNER-D2.