Serotonergic Neurotransmission in Limbic Regions May Reflect Therapeutic Response of Depressive Patients: A PET Study With 11C-WAY-100635 and 18F-MPPF.

BACKGROUND: Central serotonin (5-hydroxytryptamine [5-HT]) neurotransmission has been implicated in the etiology of depression. Most antidepressants ameliorate depressive symptoms by increasing 5-HT at synaptic clefts, but their effect on 5-HT receptors has yet to be clarified. 11C-WAY-100635 and 18F-MPPF are positron emission tomography (PET) radioligands for 5-HT1A receptors. While binding of both ligands reflects 5-HT1A receptor density, 18F-MPPF biding may also be affected by extracellular 5-HT concentrations. This dual-tracer PET study explored the neurochemical substrates underlying antidepressant effects in patients with depression. METHODS: Eleven patients with depression, including 9 treated with antidepressants, and 16 age- and sex-matched healthy individuals underwent PET scans with 11C-WAY-100635 and 18F-MPPF. Radioligand binding was determined by calculating the nondisplaceable binding potential (BPND). RESULTS: Patients treated with antidepressants showed significantly lower 18F-MPPF BPND in neocortical regions and raphe nuclei, but not in limbic regions, than controls. No significant group differences in 11C-WAY-100635 BPND were found in any of the regions. Significant correlations of BPND between 11C-WAY-100635 and 18F-MPPF were observed in limbic regions and raphe nuclei of healthy controls, but no such associations were found in antidepressant-treated patients. Moreover, 18F-MPPF BPND in limbic regions was significantly correlated with the severity of depressive symptoms. CONCLUSIONS: These results suggest a diversity of antidepressant-induced extracellular 5-HT elevations in the limbic system among depressive patients, which is associated with the individual variability of clinical symptoms following the treatment.

Characteristics and long-term outcome for congenital left main coronary artery atresia.

The prevalence of congenital left main coronary artery atresia is very low. We report the characteristics and long-term outcomes of four children with left main coronary artery atresia. Three patients had heart murmurs due to mitral regurgitation at less than 1 year old. Their myocardial ischaemia worsened on exercise with aging. In the fourth patient, hypertrophic cardiomyopathy and Noonan syndrome were suspected at 1 year old. The development of communicating arteries between the conus branch and the left anterior descending artery was detected at 7 years old. The left main coronary artery atresia was confirmed by a selective coronary angiogram at 15 years old. Congenital left main coronary artery atresia could not be diagnosed by two-dimensional echocardiography; however, the left coronary arteries were small. Two patients underwent coronary artery bypass grafting of the left anterior descending artery using the left internal thoracic artery at 3 years and 6 years old, respectively. Two patients had an angioplasty with a cut back at the orifice of the left coronary artery at 2 years old and 17 years old, respectively. Two patients had no cardiac events without medication for more than 30 years after the operation. We must differentiate the diagnosis of left main coronary artery atresia in the small left coronary arteries with mitral regurgitation during the first year. Coronary artery revascularisation and mitral annuloplasty are needed. The long-term outcome of both coronary artery bypass grafting and angioplasty were good. The degree of mitral regurgitation after surgery may affect the prognosis.

Pharmacokinetic and pharmacodynamic assessment of histamine H3 receptor occupancy by enerisant: a human PET study with a novel H3 binding ligand, [11C]TASP457.

PURPOSE: Histamine H3 receptor antagonists and inverse agonists have been extensively developed to treat sleep-wake, neurocognitive, and allied disorders. However, potential adverse effects, including insomnia, hampered the clinical use of these drugs, possibly due to their persistent interaction with the target molecules. The purpose of the present study was to estimate the pharmacokinetics and pharmacodynamics of enerisant, a novel antagonist and inverse agonist for histamine H3 receptors. METHODS: To measure the histamine H3 receptor occupancy by enerisant, positron emission tomography studies using [11C]TASP457, a specific radioligand for histamine H3 receptors, were performed in 12 healthy men at baseline and at 2 h after oral administration of enerisant hydrochloride. For three of these subjects, two additional scans were performed at 6 and 26 h after the administration. Relationships between the receptor occupancy by enerisant and its dose and plasma concentrations were then analyzed. RESULTS: Administration of enerisant hydrochloride decreased the radioligand binding in a dose-dependent manner. The estimated receptor occupancy values at 2 h varied as a function of its dose or plasma concentration. The time course of the occupancy showed persistently high levels (> 85%) in the two subjects with higher doses (25 and 12.5 mg). The occupancy was also initially high at 2 h and 6 h with the lower dose of 5 mg, but it decreased to 69.7% at 26 h. CONCLUSION: The target engagement of enerisant was demonstrated in the brains of living human subjects. The occupancy of histamine H3 receptors by enerisant at 2 h can be predicted by applying the plasma concentration of enerisant to Hill's plot. The preliminary time-course investigation showed persistently high brain occupancy with high doses of enerisant despite the decreasing plasma concentration of the drug. Five milligrams or less dose would be appropriate for the treatment for narcolepsy with initially high occupancy allowing for effective treatment of narcolepsy, and then the occupancy level would be expected to decrease to a level to avoid this drug's unwanted side effect of insomnia at night, although further research is warranted to confirm the statement since the expected decrease is based on the finding in one subject. TRIAL REGISTRATION: This study was retrospectively registered with ClinicalTrials.gov (NCT04631276) on November 17, 2020.

First-in-human in vivo imaging and quantification of monoacylglycerol lipase in the brain: a PET study with 18F-T-401.

PURPOSE: Monoacylglycerol lipase (MAGL) regulates cannabinoid neurotransmission and the pro-inflammatory arachidonic acid pathway by degrading endocannabinoids. MAGL inhibitors may accordingly act as cannabinoid-potentiating and anti-inflammatory agents. Although MAGL dysfunction has been implicated in neuropsychiatric disorders, it has never been visualized in vivo in human brain. The primary objective of the current study was to visualize MAGL in the human brain using the novel PET ligand 18F-T-401. METHODS: Seven healthy males underwent 120-min dynamic 18F-T-401-PET scans with arterial blood sampling. Six subjects also underwent a second PET scan with 18F-T-401 within 2 weeks of the first scan. For quantification of MAGL in the human brain, kinetic analyses using one- and two-tissue compartment models (1TCM and 2TCM, respectively), along with multilinear analysis (MA1) and Logan graphical analysis, were performed. Time-stability and test-retest reproducibility of 18F-T-401-PET were also evaluated. RESULTS: 18F-T-401 showed rapid uptake and gradual washout from the brain. Logan graphical analysis showed linearity in all subjects, indicating reversible radioligand kinetics. Using a metabolite-corrected arterial input function, MA1 estimated regional total distribution volume (VT) values by best identifiability. VT values were highest in the cerebral cortex, moderate in the thalamus and putamen, and lowest in white matter and the brainstem, which was in agreement with regional MAGL expression in the human brain. Time-stability analysis showed that MA1 estimated VT values with a minimal bias even using truncated 60-min scan data. Test-retest reliability was also excellent with the use of MA1. CONCLUSIONS: Here, we provide the first demonstration of in vivo visualization of MAGL in the human brain. 18F-T-401 showed excellent test-retest reliability, reversible kinetics, and stable estimation of VT values consistent with known regional MAGL expressions. PET with 18F-T-401-PET is promising tool for measurement of central MAGL.

Excess tau PET ligand retention in elderly patients with major depressive disorder.

Depression is one of the common psychiatric disorders in old age. Major depressive disorder (MDD) has been identified as a risk factor or prodrome for neurodegenerative dementias, suggesting neuropathological overlaps and a continuum between MDD and neurodegenerative disorders. In this study, we examined tau and amyloid-ß (Aß) accumulations in the brains of MDD and healthy controls using positron emission tomography (PET) to explore pathological substrates of this illness. Twenty MDD and twenty age-matched, healthy controls were examined by PET with a tau radioligand, [11C]PBB3, and an Aß radioligand, [11C]PiB. Radioligand retentions were quantified as a standardized uptake value ratio (SUVR). We also assessed clinical manifestations of the patients using the 17-item Hamilton Depression Scale, the Geriatric Depression Scale, and psychotic symptoms. Mean cortical [11C]PBB3 SUVRs in MDD patients were significantly higher than those of healthy controls. These values were higher in MDD patients with psychotic symptoms than in those without any. The present findings indicate that tau depositions may underlie MDD, and especially in patients with psychotic symptoms. PET detection of tau accumulations may provide mechanistic insights into neuronal dysfunctions in these cases and could serve as predictions of their clinical consequences.

[Robot-assisted Cardiac Surgery Council and Current Status and Future Prospect of Robotic Mitral Valve Surgery in Japan].

The Robot-assisted Cardiac Surgery Council (RACSC) was established in 2015, and consists of the members of three closely related surgical societies and associations. The RACSC conducts the review and approval of applicant surgeons and institutions. A registry system has also been established through the Japan Cardiovascular Surgery Database-National Clinical Database( JCVSD-NCD). For the last five years, including the time when robotic mitral valve surgery was first approved as a procedure covered by the Japanese social insurance system in 2018, a total of 1,161 patients were enrolled in the JCVSDNCD, with an increase of nearly 500 cases per year. These cases underwent operations in 25 approved hospitals. The mean patient age was 59±13 years( range:20-90 years), and the male to female patient ratio was 1.8 male dominant. The most common procedure was mitral valve reconstruction, and 79% of all patients underwent annuloplasty. The mean operative time was 238±100 min, the mean cardiopulmonary bypass (CPB) time was 158±69 min, and the mean aortic cross-clamp (AXC) time was 102±49 min. When these results were compared with those of the Cleveland Clinic, which treated more than 1,000 cases as an initial institutional experience, both CPB and AXC times were nearly the same. It is believed that 200 cases are needed to stabilize the CPB and AXC time. Currently in Japan, only 3 or 4 out of the 25 approved hospitals have performed more than 200 cases over the past 5 years. The 30-day hospital mortality and redo operation rate for persisting mitral regurgitation was 0.3% and 0.6%, respectively, almost equivalent to that of the Cleveland Clinic. We believe that the 5-year result for robotic mitral surgery in Japan is acceptable. It is of note, however, that the length of hospital stay was 10.8±7.6 days, much longer than that of patients at the Cleveland Clinic( 5.2±2.8 days), and the homologous blood transfusion rate was 40.3%, twofold higher than that of the Cleveland Clinic( 20.5%). Therefore, the full benefits of less invasive robotic mitral repair surgery have not yet been achieved. Further improvements in results are both essential and anticipated.

Increased Dendritic Orientation Dispersion in the Left Occipital Gyrus is Associated with Atypical Visual Processing in Adults with Autism Spectrum Disorder.

In autism spectrum disorder (ASD), the complexity-specific hypothesis explains that atypical visual processing is attributable to selective functional changes in visual pathways. We investigated dendritic microstructures and their associations with functional connectivity (FC). Participants included 28 individuals with ASD and 29 typically developed persons. We explored changes in neurite orientation dispersion and density imaging (NODDI) and brain areas whose FC was significantly correlated with NODDI parameters in the explored regions of interests. Individuals with ASD showed significantly higher orientation dispersion index (ODI) values in the left occipital gyrus (OG) corresponding to the secondary visual cortex (V2). FC values between the left OG and the left middle temporal gyrus (MTG) were significantly negatively correlated with mean ODI values. The mean ODI values in the left OG were significantly positively associated with low registration of the visual quadrants of the Adolescent/Adult Sensory Profile (AASP), resulting in a significant positive correlation with passive behavioral responses of the AASP visual quadrants; additionally, the FC values between the left OG and the left MTG were significantly negatively associated with reciprocal social interaction. Our results suggest that abnormal V2 dendritic arborization is associated with atypical visual processing by altered intermediation in the ventral visual pathway.

Effect of Therapeutic Modification on Outcomes in Heart Transplantation Over the Past Two Decades　- A Single-Center Experience in Japan.

BACKGROUND: During these 2 decades (1999-2019), many therapeutic strategies have been developed in the field of heart transplant (HTx) to improve post-HTx outcomes. In the present study, 116 consecutive HTx adults between 1999 and 2019 were retrospectively reviewed to evaluate the influences of a therapeutic modification on post HTx outcomes.Methods and Results:Patient survival, functional status and hemodynamics after HTx and modification of therapeutic strategies were reviewed. The overall cumulative survival rate at 10 and 20 years post-HTx was 96.4 and 76.7%, respectively. There were no significant differences in survival rate or exercise tolerance after HTx between extracorporeal and implantable continuous flow-LVAD. Post-HTx patient survival in patients, irrespective of the donor risk factors such as donor age, low LVEF, history of cardiac arrest, was equivalent across cohorts, while longer TIT and higher inotrope dosage prior to procurement surgery were significant risk factors for survival. In 21 patients given everolimus (EVL) due to renal dysfunction, serum creatinine significantly decreased 1 year after initiation. In 22 patients given EVL due to transplant coronary vasculopathy (TCAV), maximum intimal thickness significantly decreased 3 years after initiation. CONCLUSIONS: The analysis of a 20-year single-center experience with HTx in Japan shows encouraging improved results when several therapeutic modifications were made; for example, proactive use of donor hearts declined by other centers and the use of EVL in patients with renal dysfunction and TCAV.

PET-detectable tau pathology correlates with long-term neuropsychiatric outcomes in patients with traumatic brain injury.

Tau deposits is a core feature of neurodegenerative disorder following traumatic brain injury (TBI). Despite ample evidence from post-mortem studies demonstrating exposure to both mild-repetitive and severe TBIs are linked to tau depositions, associations of topology of tau lesions with late-onset psychiatric symptoms due to TBI have not been explored. To address this issue, we assessed tau deposits in long-term survivors of TBI by PET with 11C-PBB3, and evaluated those associations with late-life neuropsychiatric outcomes. PET data were acquired from 27 subjects in the chronic stage following mild-repetitive or severe TBI and 15 healthy control subjects. Among the TBI patients, 14 were diagnosed as having late-onset symptoms based on the criteria of traumatic encephalopathy syndrome. For quantification of tau burden in TBI brains, we calculated 11C-PBB3 binding capacity (cm3), which is a summed voxel value of binding potentials (BP*ND) multiplied by voxel volume. Main outcomes of the present study were differences in 11C-PBB3 binding capacity between groups, and the association of regional 11C-PBB3 binding capacity with neuropsychiatric symptoms. To confirm 11C-PBB3 binding to tau deposits in TBI brains, we conducted in vitro PBB3 fluorescence and phospho-tau antibody immunofluorescence labelling of brain sections of chronic traumatic encephalopathy obtained from the Brain Bank. Our results showed that patients with TBI had higher 11C-PBB3 binding capacities in the neocortical grey and white matter segments than healthy control subjects. Furthermore, TBI patients with traumatic encephalopathy syndrome showed higher 11C-PBB3 binding capacity in the white matter segment than those without traumatic encephalopathy syndrome, and regional assessments revealed that subgroup difference was also significant in the frontal white matter. 11C-PBB3 binding capacity in the white matter segment correlated with the severity of psychosis. In vitro assays demonstrated PBB3-positive tau inclusions at the depth of neocortical sulci, confirming 11C-PBB3 binding to tau lesions. In conclusion, increased 11C-PBB3 binding capacity is associated with late-onset neuropsychiatric symptoms following TBI, and a close correlation was found between psychosis and 11C-PBB3 binding capacity in the white matter.

A case report of mania with abnormal cerebral blood flow and cognitive impairment 24 years after head trauma.

BACKGROUND: Mania usually occurs secondary to organic etiologies such as head trauma within a short time of the primary condition's onset; however, there have been a few cases reported in the literature of long time spans before the manifestation of mania. The orbitofrontal cortex has been reported to be associated with manic states in bipolar disorder and with mania-inducing lesions. Head trauma commonly disrupts various cognitive functions, including attention and information processing. Traumatic brain injury patients have been shown to have greater posterior cingulate cortex and precuneus functional connectivity to the rest of the default mode network. We describe a case of secondary mania after head trauma 24 years ago with low blood flow in the orbitofrontal cortex, high blood flow in the posterior cingulate cortex, and impaired cognitive functioning, including impaired attention and lowered processing speed. CASE PRESENTATION: We describe a 30-year-old Japanese man with secondary mania and a medical history of head trauma 24 years ago. After head trauma at 6 years of age, the patient first showed apathy as a sign of frontal lobe impairment. After recovering, he experienced no psychiatric problems during adolescence, although he did show disinhibited behavior. At the onset of mania, low blood flow in the OFC and high blood flow in the PCC were observed as well as impaired cognitive function, including inattention and lowered processing speed. Abnormal cerebral blood flow was less prominent and cognitive dysfunction was partially recovered following recovery from mania, but his processing speed remained low. CONCLUSIONS: Although functional recovery from head trauma in childhood is better than that in adulthood, the brain may remain vulnerable for a long time. The risk of psychotic symptoms such as mania should be considered, even if sufficient superficial brain functional recovery is shown.

Uncinate fasciculus disruption relates to poor recognition of negative facial emotions in Alzheimer's disease: a cross-sectional diffusion tensor imaging study.

BACKGROUND: Recognising facial emotions involves visual and emotional information processing. Patients with dementia, including dementia of Alzheimer's type (DAT), are known to poorly recognise facial emotions, especially negative facial emotions. In this study, we aimed to assess if DAT patients exhibit poor facial emotional recognition, and to identify a neural basis for how poor facial emotional recognition might occur. METHODS: Magnetic resonance imaging and diffusion tensor imaging (DTI) analysis were conducted in 20 DAT patients and 15 cognitive normal (CN) subjects. The uncinate fasciculus (UF), inferior longitudinal fasciculus, and inferior fronto-occipital fasciculus were delineated by deterministic tractography. DTI parameters were calculated for each fibre. Facial emotion recognition was evaluated with the Facial Emotion Selection Test (FEST). The relationships between FEST scores and DTI parameters in each fibre were measured by partial correlation analyses with age, gender, and the Mini-Mental State Examination as covariates. Group-wise comparisons between DAT and CN subjects were performed for each DTI parameter in each fibre. RESULTS: DAT patients showed lower FEST negative emotion scores than CN subjects (P < 0.05). The score of negative emotion subscale was negatively correlated (r = -0.770, P < 0.001) to mean diffusivity of the left UF in DAT patients. There were no relationships between negative emotion subscale and the other fibre tracts. DAT patients showed no differences in the DTI parameters for each fibre compared to CN subjects. CONCLUSIONS: DAT-related prefrontal-limbic network dysfunction is associated with poor recognition of unpleasant emotions; consequently, worse facial recognition of negative emotion is observed in DAT patients.

In vivo binding of a tau imaging probe, [11 C]PBB3, in patients with progressive supranuclear palsy.

BACKGROUND: [11 C]pyridinyl-butadienyl-benzothiazole 3 is a PET imaging agent designed for capturing pathological tau aggregates in diverse neurodegenerative disorders, and would be of clinical utility for neuropathological investigations of PSP. OBJECTIVES: To explore the usefulness of [11 C]pyridinyl-butadienyl-benzothiazole 3/PET in assessing characteristic distributions of tau pathologies and their association with clinical symptoms in the brains of living PSP patients. METHODS: We assessed 13 PSP patients and 13 age-matched healthy control subjects. Individuals negative for amyloid ß PET with [11 C]Pittsburgh compound B underwent clinical scoring, MR scans, and [11 C]pyridinyl-butadienyl-benzothiazole 3/PET. RESULTS: There were significant differences in binding potential for [11 C]pyridinyl-butadienyl-benzothiazole 3 between PSP patients and healthy control subjects (P = 0.02). PSP patients exhibited greater radioligand retention than healthy control subjects in multiple brain regions, including frontoparietal white matter, parietal gray matter, globus pallidus, STN, red nucleus, and cerebellar dentate nucleus. [11 C]pyridinyl-butadienyl-benzothiazole 3 deposition in frontoparietal white matter, but not gray matter, was correlated with general severity of parkinsonian and PSP symptoms, whereas both gray matter and white matter [11 C]pyridinyl-butadienyl-benzothiazole 3 accumulations in the frontoparietal cortices were associated with nonverbal cognitive impairments. Autoradiographic and fluorescence labeling with pyridinyl-butadienyl-benzothiazole 3 was observed in gray matter and white matter of PSP motor cortex tissues. CONCLUSIONS: Our findings support the in vivo detectability of tau fibrils characteristic of PSP by [11 C]pyridinyl-butadienyl-benzothiazole 3/PET, and imply distinct and synergistic contributions of gray matter and white matte tau pathologies to clinical symptoms. [11 C]pyridinyl-butadienyl-benzothiazole 3/PET potentially provides a neuroimaging-based index for the evolution of PSP tau pathologies promoting the deterioration of motor and cognitive functions. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Benefits of the Modified Bicaval Anastomosis Technique for Orthotopic Heart Transplantation From a Size-Mismatched Marginal Donor.

BACKGROUND: Size-mismatched heart transplantation (HTx) is associated with a risk of stenosis of the caval anastomosis site or low cardiac output syndrome. We developed a modified bicaval anastomosis technique (mBCAT) that achieved an adjustable caval anastomosis to compensate for size mismatch. This study was performed to validate the rationale of the mBCAT for size-mismatched HTx.Methods and Results:This institutional consecutive series involved 106 patients who underwent HTx with the mBCAT during an 18-year period. The cohort was divided into 3 groups according to the donor-to-recipient body weight ratio: <0.8, undersized group (n=17); 0.8-1.3, size-matched group (n=68); and >1.3, oversized group (n=21); outcomes were compared. The undersized, size-matched, and oversized groups showed no significant differences in the rate of mild or worse echocardiographic tricuspid regurgitation at 1 month [1 (5.8%), 7 (10.2%), and 1 (4.8%), respectively; P=0.87] or the survival rate at 10 years [100%, 93.9%, and 100%, respectively; P=0.25]. The right heart catheter study revealed no pressure gradient across the orifices of both cavae in any patient. Additionally, the cardiac index immediately post-HTx was significantly low in the undersized group (P=0.008), but was similar to the other groups at 6 months post-HTx (P=0.16). CONCLUSIONS: The mBCAT prevented caval anastomosis-related complications in size-mismatched HTx and achieved excellent hemodynamics regardless of donor size.

Long-Term Results of Intracardiac Mesenchymal Stem Cell Transplantation in Patients With Cardiomyopathy.

BACKGROUND: Mesenchymal stem cells (MSCs), which have the potential to differentiate into cardiomyocytes or vascular endothelial cells, have been used clinically as therapy for cardiomyopathy. In this study, we aimed to evaluate the long-term follow-up results.Methods and Results:We studied 8 patients with symptomatic heart failure (HF) on guideline-directed therapy (ischemic cardiomyopathy, n=3; nonischemic cardiomyopathy, n=5) who underwent intracardiac MSC transplantation using a catheter-based injection method between May 2004 and April 2006. Major adverse events and hospitalizations were investigated up to 10 years afterward. Compared with baseline, there were no significant differences in B-type natriuretic peptide (BNP) (from 211 to 173 pg/mL), left ventricular ejection fraction (LVEF) (from 24% to 26%), and peak oxygen uptake (from 16.5 to 19.2 mL/min/kg) at 2 months. During the follow-up period, no patients experienced serious adverse events such as arrhythmias. Three patients died of pneumonia in the 1st year, liver cancer in the 6th year, and HF in the 7th year. Of the remaining 5 patients, 3 patients were hospitalized for exacerbated HF, 1 of whom required heart transplantation in the 2nd year; 2 patients survived for 10 years without worsening HF. CONCLUSIONS: The results of this exploratory study of intracardiac MSCs administration suggest further research regarding the feasibility and efficacy is warranted.

Decreased perfusion of the posterior cingulate gyri shown by a cingulate island score is a possible marker of vulnerability to behavioural and psychological symptoms of Alzheimer's disease: a pilot study.

BACKGROUND: The cingulate island score (CIScore), which indicates the Z-score ratio of the posterior cingulate gyri to the medial occipital area, has been shown to be useful for differentiating dementia with Lewy bodies from Alzheimer's disease (AD). Our aim was to investigate associations between the clinical symptoms of AD and the CIScore as an index of the relative decrease in perfusion of the posterior cingulate gyri that occurs in the early stages of AD. METHODS: Seventeen patients with early-stage AD and 13 patients with amnesic mild cognitive impairment were examined. Z-score maps of technetium-99m ethyl cysteinate dimer single-photon emission computed tomography images acquired from the patients were converted, and the CIScore was determined by using the easy Z-score imaging system. The relationships between the CIScore and clinical symptom scores were tested. RESULTS: A significant correlation was identified between the CIScore and the Neuropsychiatric Inventory Questionnaire score. No significant correlations were identified between the CIScore and other measures of cognitive function. Based on a CIScore of 0.39, we correctly differentiated patients with and without behavioural and psychological symptoms of dementia (BPSD), with a sensitivity of 72.2% and specificity of 75.0%. DISCUSSION: Using technetium-99m ethyl cysteinate dimer single-photon emission computed tomography, we observed that decreased posterior cingulate gyri perfusion, relative to the medial occipital area, in prodromal and early AD was closely associated with behavioural and psychological symptoms of dementia. Therefore, our findings suggest that CIScore is not only useful for discriminating dementia with Lewy bodies from AD, but it can also be clinically used as a specific indicator of the vulnerability to behavioural and psychological symptoms of dementia in the early stages of AD.

Detection of brain amyloid-ß deposits due to the repetitive head trauma in a former karate player.

Head trauma is a well-established epidemiological risk factor for Alzheimer's disease, but a study of early detection of its pathology has not yet been performed in human patients in vivo. To address this issue, we performed 11 C-labelled Pittsburgh compound B-positron emission tomography on a right-handed 30-year-old man with cognitive deterioration after repetitive head trauma during karate matches. Structural magnetic resonance imaging was also performed on this patient. The same positron emission tomography analysis was performed on elderly healthy controls (15 men, mean age: 70.7 ± 6.2 years). To analyze grey matter volume, structural magnetic resonance imaging was performed on age-matched healthy controls (15 men, mean age: 28.5 ± 3.6 years). The cognitive deterioration in our patient was fixed and partially improved in the 10 years after the repetitive head trauma. However, Pittsburgh compound B-non-displaceable binding potential was significantly elevated in the patient. Volume reduction was shown in the medial temporal region, cerebellum, and the basal frontal cortex, while amyloid-ß increase was shown in the bilateral prefrontal cortex. This is the first study to show an early degenerative process due to head trauma in the prefrontal cortex, where structural damage is not yet visible. Early recognition of the degenerative pathology due to repetitive head trauma by amyloid and possibly tau imaging would help clinicians determine how to treat those with early symptoms.

Tau-induced focal neurotoxicity and network disruption related to apathy in Alzheimer's disease.

OBJECTIVE: Apathy is a common neuropsychological symptom in Alzheimer's disease (AD), and previous studies demonstrated that neuronal loss and network disruption in some brain regions play pivotal roles in the pathogenesis of apathy. However, contributions of tau and amyloid-ß (Aß) depositions, pathological hallmarks of AD, to the manifestation of apathy remain elusive. METHODS: Seventeen patients with AD underwent positron emission tomography (PET) with 11C-pyridinyl-butadienyl-benzothiazole 3 (11C-PBB3) and 11C-Pittsburgh compound-B (11C-PiB) to estimate tau and Aß accumulations using standardised uptake value ratio (SUVR) images. 11C-PBB3 and 11C-PiB SUVR were compared between AD patients with high and low Apathy Scale (AS) scores. Additionally, volumetric and diffusion tensor MRI was performed in those areas where any significant difference was observed in PET analyses. Correlation and path analyses among AS and estimated imaging parameters were also conducted. RESULTS: AD patients with high AS scores showed higher 11C-PBB3 SUVR in the orbitofrontal cortex (OFC) than those with low AS scores, while 11C-PiB SUVR in any brain regions did not differ between them. Elevated 11C-PBB3 SUVR in OFC, decreased OFC thickness and decreased fractional anisotropy (FA) in the uncinate fasciculus (UNC), which is structurally connected to OFC, correlated significantly with increased scores of the AS. Path analysis indicated that increased 11C-PBB3 SUVR in OFC affects apathy directly and through reduction of OFC thickness and subsequent decrease of FA in UNC. CONCLUSIONS: The present findings suggested that tau pathology in OFC may provoke focal neurotoxicity in OFC and the following disruption of the OFC-UNC network, leading to the emergence and progression of apathy in AD.

A new arena in cardiac surgery: Pediatric coronary artery bypass surgery.

Prior to the 1970s, pediatric coronary artery bypass surgery (PCABS) was seldomly performed due to the lack of compelling surgical indications. The advent of coronary sequelae secondary to Kawasaki disease (KD) and the occurrence of coronary artery complications due to newly developed procedures, such as the arterial switch operation and early repair for intrinsic congenital coronary malformations, necessitated the development of PCABS. Because children grow rapidly and their life expectancy is very long, with increasing exercise capability requirements, the strategy for PCABS should differ from that for bypass surgery in adults. PCABS utilizing unilateral and bilateral internal thoracic arteries (ITA) has become the most reliable surgical method for children because of the distinct structure of ITAs being resistant to KD, growth potential according to the child's somatic growth and long-term patency without wall degeneration. This operation utilizing ITA grafts is now being performed worldwide and is referred to as the "Kitamura operation" for KD coronary sequelae. Notably, the use of vein grafts should be avoided in children. Likewise, this operation can now be successfully performed in infants using a surgical microscope, for congenital coronary disorders. Currently, PCABS with ITAs has been established as a new arena in cardiac surgery, following our initial attempts.

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.