Usefulness of monitoring cell-mediated immunity for predicting post-kidney transplantation viral infection

BACKGROUND

Monitoring cell-mediated immunity (CMI) can be used to estimate the risk of viral infections in kidney transplant recipients. The Immuknow (IMK) assay measures CD4(+) T-cell adenosine triphosphate activity, assesses patient CMI status, and assists clinicians in determining the risk of viral infection.

METHODS

We retrospectively analyzed 224 IMK values in 39 kidney transplant recipients at our institution from April 2012 to January 2013. We analyzed the relationship between IMK value and viral infection during the early and late post-transplantation periods. Multiple regression analyses were performed, to determine which factors impacted the results of the IMK assay.

RESULTS

Eight patients developed viral infections, including BK virus, cytomegalovirus, herpes simplex, and shingles. Five infections occurred in the early post-transplantation period (<50 d) and 3 in the late period (>120 d). The IMK levels in patients who developed an infection in the early period were within normal limits; however, those in the late period were significantly lower than 200 ng/mL (421.0 ± 062.6 for early vs 153.7 ± 72.7 for late; P = .02). Our multiple regression analyses indicated that peripheral white blood cell and neutrophil counts affected IMK values (P = .03 and P = .02, respectively).

CONCLUSIONS

The IMK assay is a useful test for identifying patients at risk for post-transplantation viral infections in the late transplant period.

Ubiquilin-1 immunoreactivity is concentrated on Hirano bodies and dystrophic neurites in Alzheimer's disease brains

AIMS

Ubiquilin-1 acts as an adaptor protein that mediates the translocation of polyubiquitinated proteins to the proteasome for degradation. Although previous studies suggested a key role of ubiquilin-1 in the pathogenesis of Alzheimer's disease (AD), a direct relationship between ubiquilin-1 and Hirano bodies in AD brains remains unknown.

METHODS

By immunohistochemistry, we studied ubiquilin-1 and ubiquilin-2 expression in the frontal cortex and the hippocampus of six AD and 13 control cases.

RESULTS

Numerous Hirano bodies, accumulated in the hippocampal CA1 region of AD brains, expressed intense immunoreactivity for ubiquilin-1. They were much less frequently found in control brains. However, Hirano bodies did not express a panel of markers for proteasome, autophagosome or pathogenic proteins, such as ubiquilin-2, ubiquitin, p62, LC3, beclin-1, HDAC6, paired helical filament (PHF)-tau, protein-disulphide isomerase (PDI) and phosphorylated TDP-43, but some of them expressed C9orf72. Ubiquilin-1-immunoreactive deposits were classified into four distinct morphologies, such as rod-shaped structures characteristic of Hirano bodies, dystrophic neurites contacting senile plaques, fragmented structures accumulated in the lesions affected with severe neuronal loss, and thread-shaped structures located mainly in the molecular layer of the hippocampus.

CONCLUSIONS

Ubiquilin-1 immunoreactivity is concentrated on Hirano bodies and dystrophic neurites in AD brains, suggesting that aberrant expression of ubiquilin-1 serves as one of pathological hallmarks of AD.

PLD3 is accumulated on neuritic plaques in Alzheimer's disease brains

INTRODUCTION

Recently, a whole-exome sequencing (WES) study showed that a rare variant rs145999145 composed of p.Val232Met located in exon 7 of the phospholipase D3 (PLD3) gene confers a doubled risk for late-onset Alzheimer's disease (AD). Knockdown of PLD3 elevates the levels of extracellular amyloid-beta (Aβ), suggesting that PLD3 acts as a negative regulator of Aβ precursor protein (APP) processing. However, the precise cellular location and distribution of PLD3 in AD brains remain largely unknown.

METHODS

By quantitative RT-PCR (qPCR), western blot, immunohistochemistry, and bioinformatics analysis, we studied PLD3 expression patterns and levels in a series of AD and control brains, including amyotrophic lateral sclerosis, Parkinson's disease, multiple system atrophy, and non-neurological cases.

RESULTS

The levels of PLD3 mRNA and protein expression were reduced modestly in AD brains, compared with those in non-AD brains. In all brains, PLD3 was expressed constitutively in cortical neurons, hippocampal pyramidal and granular neurons but not in glial cells. Notably, PLD3 immunoreactivity was accumulated on neuritic plaques in AD brains. We identified the human granulin (GRN) gene encoding progranulin (PRGN) as one of most significant genes coexpressed with PLD3 by bioinformatics database search. PLD3 was actually coexpressed and interacted with PGRN both in cultured cells in vitro and in AD brains in vivo.

CONCLUSIONS

We identified an intense accumulation of PLD3 on neuritic plaques coexpressed with PGRN in AD brains, suggesting that PLD3 plays a key role in the pathological processes of AD.

Concordance between (99m)Tc-ECD SPECT and 18F-FDG PET interpretations in patients with cognitive disorders diagnosed according to NIA-AA criteria

OBJECTIVES

The purpose of this study was to clarify the concordance of diagnostic abilities and interobserver agreement between 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and brain perfusion single photon-emission computed tomography (SPECT) in patients with Alzheimer's disease (AD) who were diagnosed according to the research criteria of the National Institute of Aging-Alzheimer's Association Workshop.

METHODS

Fifty-five patients with "AD and mild cognitive impairment (MCI)" (n = 40) and "non-AD" (n = 15) were evaluated with 18F-FDG PET and (99m)Tc-ethyl cysteinate dimer (ECD) SPECT during an 8-week period. Three radiologists independently graded the regional uptake in the frontal, temporal, parietal, and occipital lobes as well as the precuneus/posterior cingulate cortex in both images. Kappa values were used to determine the interobserver reliability regarding regional uptake.

RESULTS

The regions with better interobserver reliability between 18F-FDG PET and (99m)Tc-ECD SPECT were the frontal, parietal, and temporal lobes. The (99m)Tc-ECD SPECT agreement in the occipital lobes was not significant. The frontal, temporal, and parietal lobes showed good correlations between 18F-FDG PET and (99m)Tc-ECD SPECT in the degree of uptake, but the occipital lobe and precuneus/posterior cingulate cortex did not show good correlations. The diagnostic accuracy rates of "AD and MCI" ranged from 60% to 70% in both of the techniques.

CONCLUSIONS

The degree of uptake on 18F-FDG PET and (99m)Tc-ECD SPECT showed significant correlations in the frontal, temporal, and parietal lobes. The diagnostic abilities of 18F-FDG PET and (99m)Tc-ECD SPECT for "AD and MCI," when diagnosed according to the National Institute of Aging-Alzheimer's Association Workshop criteria, were nearly identical.

Simplification of the modified Gallyas method

The Gallyas method is a silver impregnation technique that is essential in the field of neuropathology because of its high sensitivity for the detection of argentophilic inclusion bodies in the central nervous system. In Japan, the Gallyas method has improved and is widely used as the “modified Gallyas method”. However, this method is not popularly used in general pathology laboratories because of the need for special reagents, several staining processes, and skilled techniques. The objective of the current study was to provide a simplified Gallyas method. We omitted the lanthanum nitrate step from the staining process and verified the adequacy in comparison with the original method as well as immunohistochemistry, using specimens from patients of Alzheimer's disease, argyrophilic grain disease, multiple system atrophy, Pick's disease, and Lewy body disease. The simplified method provided good staining to all the structures in archival tissues, compared with the modified Gallyas method in a significantly shorter staining time. The lanthanum nitrate step can be omitted from the modified Gallyas method, resulting in reduction in the number of reagents required and shortening of the staining time.

Temperament and character in remitted and symptomatic patients with schizophrenia: modulation by the COMT Val158Met genotype

While research on remission in schizophrenia has gained attention, personality characteristics associated with remission in schizophrenia have been under-studied. A functional valine-to-methionine (Val158Met) polymorphism in the catechol-O-methyltransferase (COMT) gene is shown to modify clinical presentation of schizophrenia despite weak or no association with the disorder itself. Studies also report that this polymorphism can affect personality traits. We aimed to examine personality traits of remitted patients with schizophrenia as compared to symptomatic patients and healthy controls and to investigate whether the COMT Val158Met polymorphism influences their personality. Scores on the Temperament and Character Inventory were compared between 34 remitted outpatients with schizophrenia, age- and sex-matched 72 symptomatic outpatients with schizophrenia, and matched 247 healthy individuals. The effect of COMT Val158Met polymorphism on personality was examined in each group. The analysis of covariance, controlling for confounding variables, revealed that compared to healthy controls, symptomatic patients exhibited a pervasively altered personality profile whereas remitted patients showed alterations in more limited personality dimensions and demonstrated normal levels of novelty-seeking, reward dependence and cooperativeness. The two-way analysis of covariance, with genotype and sex as between-subject factors and confounders as covariates, revealed that Met carriers demonstrated significantly lower reward dependence and cooperativeness than Val homozygotes in symptomatic patients; while no significant genotype effect was found in remitted patients or in healthy individuals. These findings indicate that remitted patients with schizophrenia have a relatively adaptive personality profile compared to symptomatic patients. The COMT Val158Met polymorphism might have a modulating effect on the relationship between personality and remission.

Accuracy of spinal curvature assessed by a computer-assisted device and anthropometric indicators in discriminating vertebral fractures among individuals with back pain

This study examined the accuracy of thoracic and lumbar kyphotic angles as well as anthropometric indicators for discriminating patients with vertebral fracture among Japanese women >50 years old with back pain. Along with region-specific kyphotic angles and anthropometric indicators, the combination of thoracic and lumbar kyphotic angles offered the highest accuracy.

INTRODUCTION

Vertebral fractures have been associated with thoracic kyphosis. However, reports on lumbar kyphotic changes in association with vertebral fracture are scarce. This study investigated the accuracy of thoracic kyphotic angle (TKA) and lumbar kyphotic angle (LKA) measurements as well as anthropometric indicators (wall-occiput distance (WOD) and rib-pelvis distance (RPD)) in discriminating patients with vertebral fracture.

METHODS

Lateral radiographs of the spine were obtained in 70 postmenopausal Japanese women who visited an orthopedic clinic with low back pain (mean age, 76.2 ± 9.0 years). Radiographic vertebral fracture was diagnosed using quantitative measurement according to Japanese criteria. Osteoarthritis (OA) was defined as Kellgren-Lawrence (KL) grade 3 or higher. TKA and LKA were measured using SpinalMouse®. WOD and RPD were also measured.

RESULTS

At least one vertebral fracture was present in 49 subjects (70 %). Women with vertebral fractures showed significant increases in LKA, TKA + LKA, and WOD and decreases in RPD. Logistic regression analysis showed significant association between TKA + LKA and vertebral fracture independent of the presence of OA. Receiver operating characteristic analysis revealed that TKA was useful for discriminating thoracic fractures (area under the curve (AUC), 0.730) and LKA was useful for lumbar fractures (AUC, 0.691). The combination of TKA + LKA offered the highest accuracy for detecting thoracic, lumbar, and any vertebral fractures, with AUCs of 0.779, 0.728, and 0.783, respectively. WOD and RPD showed low-to-moderate accuracies for thoracic, lumbar, and any vertebral fractures.

CONCLUSIONS

Assessment of spinal kyphosis by SpinalMouse® as well as anthropometric indicators proved useful in discriminating subjects with vertebral fractures. These convenient and radiation-free methods could contribute to early diagnosis of vertebral fractures and subsequent appropriate treatment, thus preventing additional osteoporotic fractures.

LC3, an autophagosome marker, is expressed on oligodendrocytes in Nasu-Hakola disease brains

Background

Nasu-Hakola disease (NHD) is a rare autosomal recessive disorder characterized by sclerosing leukoencephalopathy and multifocal bone cysts, caused by a loss-of-function mutation of either DAP12 or TREM2. TREM2 and DAP12 constitute a receptor/adaptor signaling complex expressed exclusively on osteoclasts, dendritic cells, macrophages, and microglia. Neuropathologically, NHD exhibits profound loss of myelin and accumulation of axonal spheroids, accompanied by intense gliosis accentuated in the white matter of the frontal and temporal lobes. At present, the molecular mechanism responsible for development of leukoencephalopathy in NHD brains remains totally unknown.

Methods

By immunohistochemistry, we studied the expression of microtubule-associated protein 1 light chain 3 (LC3), an autophagosome marker, in 5 NHD and 12 control brains.

Results

In all NHD brains, Nogo-A-positive, CNPase-positive oligodendrocytes surviving in the non-demyelinated white matter intensely expressed LC3. They also expressed ubiquitin, ubiquilin-1, and histone deacetylase 6 (HDAC6) but did not express Beclin 1 or sequestosome 1 (p62). Substantial numbers of axonal spheroids were also labeled with LC3 in NHD brains. In contrast, none of oligodendrocytes expressed LC3 in control brains. Furthermore, surviving oligodendrocytes located at the demyelinated lesion edge of multiple sclerosis (MS) did not express LC3, whereas infiltrating Iba1-positive macrophages and microglia intensely expressed LC3 in MS lesions.

Conclusions

These results propose a novel hypothesis that aberrant regulation of autophagy might induce oligodendrogliopathy causative of leukoencephalopathy in NHD brains.

TMEM106B expression is reduced in Alzheimer's disease brains

Introduction

TMEM106B is a transmembrane glycoprotein of unknown function located within endosome/lysosome compartments expressed ubiquitously in various cell types. Previously, the genome-wide association study (GWAS) identified a significant association of TMEM106B single nucleotide polymorphisms (SNPs) with development of frontotemporal lobar degeneration with ubiquitinated TAR DNA-binding protein-43 (TDP-43)-positive inclusions (FTLD-TDP), particularly in the patients exhibiting the progranulin (PGRN) gene (GRN) mutations. Recent studies indicate that TMEM106B plays a pathological role in various neurodegenerative diseases, including Alzheimer’s disease (AD). However, at present, the precise levels of TMEM106B expression in AD brains remain unknown.

Methods

By quantitative reverse transcription (RT)-PCR (qPCR), western blot and immunohistochemistry, we studied TMEM106B and PGRN expression levels in a series of AD and control brains, including amyotrophic lateral sclerosis, Parkinson’s disease, multiple system atrophy and non-neurological cases.

Results

In AD brains, TMEM106B mRNA and protein levels were significantly reduced, whereas PGRN mRNA levels were elevated, compared with the levels in non-AD brains. In all brains, TMEM106B was expressed in the majority of cortical neurons, hippocampal neurons, and some populations of oligodendrocytes, reactive astrocytes and microglia with the location in the cytoplasm. In AD brains, surviving neurons expressed intense TMEM106B immunoreactivity, while senile plaques, neurofibrillary tangles and the perivascular neuropil, almost devoid of TMEM106B, intensely expressed PGRN.

Conclusions

We found an inverse relationship between TMEM106B (downregulation) and PGRN (upregulation) expression levels in AD brains, suggesting a key role of TMEM106B in the pathological processes of AD.

Benzodiazepines, benzodiazepine-like drugs, and typical antipsychotics impair manual dexterity in patients with schizophrenia

Impaired dexterity is a major psychomotor deficit reported in patients with schizophrenia. In the present study, the Purdue pegboard test was used to compare the manual dexterity in patients with schizophrenia and healthy controls. We also examined the influence of antipsychotics, benzodiazepines, and benzodiazepine-like drugs on manual dexterity. Subjects were 93 patients with schizophrenia and 93 healthy controls, matched for sex and age distributions. Control subjects scored significantly higher on all scores of Purdue pegboard than patients with schizophrenia. Age, PANSS negative symptom scale, typical antipsychotic dose, and use of benzodiazepines and/or benzodiazepine-like drugs were negatively correlated with the pegboard scores in patients with schizophrenia. The present results indicate that patients with schizophrenia have impaired gross and fine fingertip dexterity compared to healthy controls. The use of typical antipsychotics and benzodiazepines and/or benzodiazepine-like drugs, but not atypical antipsychotics, had significant negative impact on dexterity in patients with schizophrenia. Psychiatrists should be aware that some psychotropic medications may enhance the disability caused by the impairment of dexterity in patients with schizophrenia.

Comparison between brain CT and MRI for voxel-based morphometry of Alzheimer's disease

The voxel-based morphometry (VBM) technique using brain magnetic resonance imaging (MRI) objectively maps gray matter loss on a voxel-by-voxel basis after anatomic standardization. In patients with Alzheimer's disease (AD), reductions of gray matter volume, mainly in the medial temporal structures, have been reported; however, inhomogeneity and geometric distortion of the field intensity hampers the reproducibility of MRI. In the present study, we developed a novel computed tomography (CT)-based VBM method and used this technique to detect volume loss in AD patients as compared with normal controls. The results were compared with MRI-based VBM using the same subjects. Pittsburgh Compound B ((11)C-PIB) positron emission tomography (PET)/CT was performed and two experts in neuro-nuclear medicine judged whether regional amyloid β load was consistent with a diagnosis of AD. Before the injection of (11)C-PIB, high-quality CT scans were obtained using the same PET/CT equipment. MRI was performed within a mean interval of 25.1 ± 8.2 days before the PET/CT scan. Using statistical parametric mapping 8 (SPM8), the extracted gray matter images from CT and MRI were spatially normalized using a gray matter template and smoothed using a Gaussian kernel. Group comparisons were performed using SPM8 between five (11)C-PIB-positive patients with probable AD and seven (11)C-PIB-negative age-matched controls with normal cognition. Gray matter volumes in the bilateral medial temporal areas were reduced in the AD group as compared with the cognitively normal group in both CT-based VBM (in the left; P < 0.0001, cluster size 2776 and in the right; P < 0.0001, cluster size 630) and MRI-based VBM (in the left; P < 0.0001, cluster size 381 and in the right, P < 0.0001, cluster size 421). This newly developed CT-based VBM technique can detect significant atrophy in the entorhinal cortex in probable AD patients as previously reported using MRI-based VBM. However, CT-VBM was more sensitive and revealed larger areas of significant atrophy than MR-VBM.