Evaluation of the SARS-CoV-2 RNA detection reagent LAMPdirect Genelyzer KIT using nasopharyngeal swab and saliva samples.

The LAMPdirect Genelyzer KIT allows for the detection of SARS-CoV-2 RNA in saliva samples with a loop-mediated isothermal amplification (LAMP) method and generates results within 20 min. It has been approved by the Pharmaceuticals and Medical Devices Agency in Japan. In this study, the performance of the LAMPdirect Genelyzer KIT was compared with that of the RT-qPCR reference method using 50 nasopharyngeal swabs and 100 saliva samples. In addition, we evaluated the applicability of an alternative reverse transcriptase and the effects of an inactivation buffer. The total agreement rates were 80.0 % and 82.0 % for nasopharyngeal and saliva samples, respectively. When considering samples at the detection limit (50 copies/reaction) that increases the chance of transmission between humans, the total agreement rates were 100% and 94.1% for nasopharyngeal and saliva samples, respectively. The LAMP method is simple, fast, and inexpensive, making it useful for small medical institutions or rural areas.

EEG resting-state networks in Alzheimer's disease associated with clinical symptoms.

Alzheimer's disease (AD) is a progressive neuropsychiatric disease affecting many elderly people and is characterized by progressive cognitive impairment of memory, visuospatial, and executive functions. As the elderly population is growing, the number of AD patients is increasing considerably. There is currently growing interest in determining AD's cognitive dysfunction markers. We used exact low-resolution-brain-electromagnetic-tomography independent-component-analysis (eLORETA-ICA) to assess activities of five electroencephalography resting-state-networks (EEG-RSNs) in 90 drug-free AD patients and 11 drug-free patients with mild-cognitive-impairment due to AD (ADMCI). Compared to 147 healthy subjects, the AD/ADMCI patients showed significantly decreased activities in the memory network and occipital alpha activity, where the age difference between the AD/ADMCI and healthy groups was corrected by linear regression analysis. Furthermore, the age-corrected EEG-RSN activities showed correlations with cognitive function test scores in AD/ADMCI. In particular, decreased memory network activity showed correlations with worse total cognitive scores for both Mini-Mental-State-Examination (MMSE) and Alzheimer's Disease-Assessment-Scale-cognitive-component-Japanese version (ADAS-J cog) including worse sub-scores for orientation, registration, repetition, word recognition and ideational praxis. Our results indicate that AD affects specific EEG-RSNs and deteriorated network activity causes symptoms. Overall, eLORETA-ICA is a useful, non-invasive tool for assessing EEG-functional-network activities and provides better understanding of the neurophysiological mechanisms underlying the disease.

SARS-CoV-2 specific T cell and humoral immune responses upon vaccination with BNT162b2: a 9 months longitudinal study.

The humoral and cellular immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) upon the coronavirus disease 2019 (COVID-19) vaccination remain to be clarified. Hence, we aimed to investigate the long-term chronological changes in SARS-CoV-2 specific IgG antibody, neutralizing antibody, and T cell responses during and after receiving the BNT162b2 vaccine. We performed serological, neutralization, and T cell assays among 100 hospital workers aged 22-73 years who received the vaccine. We conducted seven surveys up to 8 months after the second vaccination dose. SARS-CoV-2 spike protein-specific IgG (IgG-S) titers and T cell responses increased significantly following the first vaccination dose. The highest titers were observed on day 29 and decreased gradually until the end of the follow-up period. There was no correlation between IgG-S and T cell responses. Notably, T cell responses were detected on day 15, earlier than the onset of neutralizing activity. This study demonstrated that both IgG-S and T cell responses were detected before acquiring sufficient levels of SARS-CoV-2 neutralizing antibodies. These immune responses are sustained for approximately 6 to 10 weeks but not for 7 months or later following the second vaccination, indicating the need for the booster dose (i.e., third vaccination).

Protein synthesis in the posterior cingulate cortex in Alzheimer's disease.

BACKGROUND: Neuroimaging studies using (18) F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) and single photon emission computed tomography (SPECT) have shown that the posterior cingulate cortex (PCC) is the primary and most prominent area of cerebral metabolic and perfusional decrement in early Alzheimer's disease (AD). We carried out the present preliminary study to investigate whether a decline of cerebral blood flow (CBF) in the PCC in early to moderate AD was accompanied with that of cerebral protein synthesis (CPS). METHODS: We carried out both N-isopropyl-p-[123I] iodoamphetamine SPECT (IMP-SPECT) and L-[methyl-11C] methionine positron emission tomography (MET-PET) in eight AD patients with apolipoprotein E epsilon 4 allele in the early to moderate stage. We also carried out IMP-SPECT in eight healthy controls (HC). We located 32 regions of interest (ROI), and values of regional MET or IMP uptakes were averaged in five regions; the frontal lobe (FL), the parietal lobe (PL), the medial temporal lobe (MTL), PCC and the occipital lobe. Furthermore, the values in the FL, PL, MTL and PCC were divided by values in the occipital areas, and normalized values of regional CBF (rCBF) and CPS (rCPS) were calculated. Then, the rCBF in the FL, PL, MTL and PCC were compared between AD and HC. In addition, the rCBF and rCPS were compared in the FL, PL, MTL and PCC of AD. RESULTS: The rCBF in the PCC, but not in the other three regions, was significantly lower in AD than in HC. The rCBF was significantly lower than rCPS in the PCC, but rCBF and rCPS were comparable in the other three regions in AD. CONCLUSIONS: The CBF reduction in the PCC in AD was partly caused by neuronal loss in the PCC and partly supported the hypothesis that CBF reduction in the PCC was a result of functional deafferentation by neural degeneration in areas other than the PCC.

KIBRA genetic polymorphism influences episodic memory in Alzheimer's disease, but does not show association with disease in a Japanese cohort.

BACKGROUND/AIMS: A single-nucleotide polymorphism (SNP) in the KIBRA gene, rs17070145, was reported to be significantly associated with episodic memory in cognitively normal cohorts. This observation has expanded genetic studies on KIBRA to Alzheimer's disease (AD). Importantly, the association between KIBRA and episodic memory in AD has never been addressed. In this study, we investigated whether the KIBRA rs17070145 SNP influences AD episodic memory and the disease in a Japanese cohort. METHODS: Blood samples from 346 AD patients and 375 normal cognitive controls were collected and genotyped for rs17070145. Episodic memory was measured in 32 AD patients, diagnosed for the first time, by use of the Rivermead Behavioral Memory Test (RBMT). RESULTS: We found that KIBRA C allele carriers scored significantly lower than KIBRA non-C carriers on both RBMT total profile score (p = 0.042, effect size = 0.84) and RBMT total screening score (p < 0.001, effect size = 1.42). The KIBRA gene did not show association with AD in our Japanese cohort. CONCLUSION: Our results evidence a strong association between the KIBRA gene and episodic memory impairment in AD, but show no influence on AD in our Japanese cohort. We propose that KIBRA might have an effect similar to cognitive reserve.

Validation of grading scale for evaluating symptoms of idiopathic normal-pressure hydrocephalus.

BACKGROUND/AIMS: We developed an idiopathic normal-pressure hydrocephalus grading scale (iNPHGS) to classify a triad of disorders (cognitive impairment, gait disturbance and urinary disturbance) of iNPH with a wide range of severity. The purpose of this study was to assess the reliability and validity of this scale in 38 patients with iNPH. RESULTS: The interrater reliability of this scale was high. The iNPHGS cognitive domain score significantly correlated with the cognitive test scores, including the Mini-Mental State Examination (MMSE), the gait domain score with the Up and Go Test and Gait Status Scale scores, and the urinary domain score with the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) score. The MMSE, Gait Status Scale and ICIQ-SF scores significantly improved in patients whose iNPHGS scores improved after CSF tapping but not in those whose iNPHGS scores did not improve after CSF tapping. Fourteen of the 38 patients received shunt operations. In these 14 patients, changes in the iNPHGS cognitive and urinary domains after CSF tapping were significantly associated with the changes after the shunt operation.

Quasispecies Analyses of the HIV-1 Near-full-length Genome With Illumina MiSeq.

Human immunodeficiency virus type-1 (HIV-1) exhibits high between-host genetic diversity and within-host heterogeneity, recognized as quasispecies. Because HIV-1 quasispecies fluctuate in terms of multiple factors, such as antiretroviral exposure and host immunity, analyzing the HIV-1 genome is critical for selecting effective antiretroviral therapy and understanding within-host viral coevolution mechanisms. Here, to obtain HIV-1 genome sequence information that includes minority variants, we sought to develop a method for evaluating quasispecies throughout the HIV-1 near-full-length genome using the Illumina MiSeq benchtop deep sequencer. To ensure the reliability of minority mutation detection, we applied an analysis method of sequence read mapping onto a consensus sequence derived from de novo assembly followed by iterative mapping and subsequent unique error correction. Deep sequencing analyses of aHIV-1 clone showed that the analysis method reduced erroneous base prevalence below 1% in each sequence position and discarded only < 1% of all collected nucleotides, maximizing the usage of the collected genome sequences. Further, we designed primer sets to amplify the HIV-1 near-full-length genome from clinical plasma samples. Deep sequencing of 92 samples in combination with the primer sets and our analysis method provided sufficient coverage to identify >1%-frequency sequences throughout the genome. When we evaluated sequences of pol genes from 18 treatment-naïve patients' samples, the deep sequencing results were in agreement with Sanger sequencing and identified numerous additional minority mutations. The results suggest that our deep sequencing method would be suitable for identifying within-host viral population dynamics throughout the genome.

Natural polymorphism S119R of HIV-1 integrase enhances primary INSTI resistance.

Integrase strand transfer inhibitors (INSTIs), which block proviral DNA integration into the host chromosome, are clinically effective against HIV-1 isolates exhibiting resistance to other classes of antiretroviral agents. Although naturally occurring amino acid variation has been less frequently observed in the integrase region, the functional constraints of this variation on primary INSTI resistance-associated mutations are not fully understood. In the present study, we focused on the S119G/R/P/T (S119X) polymorphisms, which are frequently observed in HIV-1 sequences derived from clinical specimens (naïve, n=458, 26%). The frequency of the S119X polymorphism together with Q148H/R (n=8, 63%) or N155H (n=12, 83%) was relatively high compared with that of naïve group. Our in vitro assays revealed that S119G/P/T alone exerted no effect on the susceptibility to INSTIs, whereas S119R enhanced the level of INSTI resistance induced by well-known INSTI resistance-associated mutations (Y143C, Q148H or N155H). Notably, the S119R polymorphism contributed to a significant (5.9-fold) increase in dolutegravir resistance caused by G140S/Q148H. Analysis of two cases of virological failure during raltegravir-based therapy showed that the accumulation and the rapid evolution of primary INSTI resistance-associated mutations coincided with the S119R mutation. These data highlight the role of the S119X polymorphism in INSTI resistance, and this polymorphism might be linked to the potential treatment outcome with INSTI-based therapy.

Different characteristics of cognitive impairment in elderly schizophrenia and Alzheimer's disease in the mild cognitive impairment stage.

We compared indices of the revised version of the Wechsler Memory Scale (WMS-R) and scaled scores of the five subtests of the revised version of the Wechsler Adult Intelligence Scale (WAIS-R) in 30 elderly schizophrenia (ES) patients and 25 Alzheimer's disease (AD) patients in the amnestic mild cognitive impairment (aMCI) stage (AD-aMCI). In the WMS-R, attention/concentration was rated lower and delayed recall was rated higher in ES than in AD-aMCI, although general memory was comparable in the two groups. In WAIS-R, digit symbol substitution, similarity, picture completion, and block design scores were significantly lower in ES than in AD-aMCI, but the information scores were comparable between the two groups. Delayed recall and forgetfulness were less impaired, and attention, working memory and executive function were more impaired in ES than in AD-aMCI. These results should help clinicians to distinguish ES combined with AD-aMCI from ES alone.

Global cerebral hypoperfusion in preclinical stage of idiopathic normal pressure hydrocephalus.

In patients with idiopathic normal pressure hydrocephalus (iNPH), ventriculomegaly and narrowed subarachnoid spaces at the high convexity appear in magnetic resonance (MR) images before the occurrence of objective symptoms. In addition, quantitative regional cerebral blood flow (rCBF) has been reported to be reduced in iNPH patients with objective symptoms. To determine whether reduced rCBF is responsible for the appearance of symptoms, we compared rCBF in patients with suspected iNPH with no objective triad symptoms (NOS), iNPH patients with apparent objective triad symptoms (AOS) and normal control subjects (NC). Regional CBF was quantified in 35 Regions-of-interest (ROIs) by 123I-IMP single photon emission computed tomography (SPECT) using the autoradiography (ARG) method. Multiple comparisons showed that, in all brain regions examined except for in the frontal white matter, rCBF in the NOS group was significantly lower than that in the NC group, but in all brain regions, not significantly different from that of the AOS group. These results suggest that factors other than rCBF in the resting state are responsible for the occurrence of objective symptoms of iNPH.

[Language and semantic memory impairment in a patient with motor neuron disease and semantic dementia: a case report].

We report the rare case of a 59-year-old man with motor neuron disease and semantic dementia (SD-MND); SD-MND was in a very early stage, and its clinical progression, especially with regard to language impairment, and abnormalities on neuroimages were evaluated for 3 years. The patient complained only of difficulties in recalling names of acquaintances and in writing kanji characters. After 1 year, he experienced difficulty in describing common objects. He developed two-way anomia only in some words, which varied from day to day. His anomia was not category-specific and was noted even with respect to words that describe color. In addition to experiencing difficulty in writing kanji characters, he experienced difficulty in writing kana characters. Muscle atrophy was observed, and he experienced weakness in his limbs, especially in the right upper limb; however, bulbar symptoms were not observed. At this point, he fulfilled the diagnostic criteria for MND. In the next year, semantic memory impairment became apparent, and he was subsequently diagnosed with SD. Deterioration in his ability to name objects in all categories, except body parts, was noted. Further, the ability of writing both kana and kanji characters was increasingly impaired. He developed bulbar symptoms and experienced increased muscle weakness. The characteristics of this patient differed from those of SD patients without MND with regard to the difficulty in writing kana characters and naming colors even though the SD-MND was in the early stage. Further, the pattern of brain hypoperfusion was different from that observed for SD patients without MND. In the case of this patient, brain hypoperfusion was found not only in the left anterior temporal lobe but also in the frontal lobe. The characteristics of his language symptoms might be related to the specific pattern of brain hypoperfusion, which might be commonly observed in patients with dementia and MND.

Neuropsychiatric symptoms in patients with idiopathic normal pressure hydrocephalus.

OBJECTIVE: To clarify the characteristics of neuropsychiatric symptoms in patients with idiopathic normal pressure hydrocephalus (iNPH). METHODS: Neuropsychiatric symptoms of 64 iNPH patients with mild triad symptoms from three kinds of hospitals were evaluated with the Neuropsychiatric Inventory (NPI) and compared with 126 patients with Alzheimer's disease (AD). RESULTS: The most frequently observed neuropsychiatric symptom in the iNPH patients was apathy followed by anxiety and aggression. No symptom was more prevalent or more severe in iNPH than in AD. The severity of cognitive impairment was correlated with both aberrant motor activity and apathy. CONCLUSIONS: Neuropsychiatric symptoms were mild in patients with iNPH and apathy was the most prevalent symptom. The correlation between neuropsychiatric symptoms and cognitive impairment in iNPH appears to arise from a common pathology in the frontal lobe.