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Mori, H.

Publications and source records attributed to Mori, H..

4 recordsLinked to original sources

Comparative evaluation of the GeeniusTM HIV 1/2 Confirmatory Assay and the HIV-1 and HIV-2 Western blots in the Japanese population

Accurate diagnosis of earlier HIV infection is essential for treatment and prevention. Currently, confirmation tests of HIV infection in Japan are performed using Western blot (WB), but WB has several limitations including low sensitivity and cross-reactivity between HIV-1 and HIV-2 antibodies. To address these problems, a new HIV testing algorithm and a more reliable confirmation and HIV-1/2 differentiation assay are required. The Bio-Rad Geenius HIV-1/2 Confirmatory Assay (Geenius) has recently been approved and recommended for use in the revised guidelines for diagnosis of HIV infection by the Center for Disease Control and Prevention (USA). We made comprehensive comparison of the performance of Geenius and the Bio-Rad NEW LAV BLOT 1 and 2 (NLB 1 and 2) which are WB kits for HIV-1 and HIV-2, respectively, to examine if Geenius is a suitable alternative to these WB assays which are now being used in HIV testing in Japan. A total of 166 HIV-1 positive samples (146 from patients with established HIV-1 infection and 20 from patients with acute infection), five HIV-1 seroconversion panels containing 21 samples and 30 HIV-2 positive samples were used. In addition, a total of 140 HIV negative samples containing 10 false-positives on screening tests were examined. The sensitivity of Geenius and NLB 1 for HIV-1 positive samples was 99.3% and 98.6%, respectively. Geenius provided more positive results in the samples from acute infections and detected positivity 0 to 32 days earlier in seroconversion panels than NLB 1. NLB 2 gave positive results in 12.3% of HIV-1 positive samples. The sensitivity of both Geenius and NLB 2 for HIV-2 positive samples was 100%. The specificity of Geenius, NLB 1 and NLB 2 was 98.5%, 81.5% and 90.0%, respectively. Geenius is an attractive alternative to WB for confirmation and differentiation of HIV-1 and HIV-2 infections. The adaptation of Geenius to the HIV testing algorithm may be advantageous for rapid diagnosis and the reduction of testing costs.

molecular biology

Protective effects of low-intensity pulsed ultrasound on mandibular condylar cartilage exposed to mechanical overloading

The aim of this study was to examine the role of low-intensity pulsed ultrasound (LIPUS) exposure in the onset and early progression of temporomandibular joint (TMJ) osteoarthritis (TMJ-OA) induced by mechanical overloading. Fifteen-week-old male Wistar rats were divided into two experimental groups and a control group (n = 5 each). In the experimental groups, both TMJs were subjected to mechanical overloading by forced mouth opening using a jaw-opening device for 3 h/day for 5 continuous days. After mechanical overloading, TMJs in one experimental group were exposed to LIPUS for 20 min/day. After the experiments, mandibles were resected from the rats, and the condyles were processed. The bones were analyzed using high-resolution microcomputed tomography (micro-CT). The resected TMJs were also subjected to histological analysis and immunohistochemical staining. Micro-CT images of the mandibular condyle showed severe subchondral trabecular bone loss in the experimental group with overloading. Treatment with LIPUS after overloading resulted in decreased subchondral trabecular bone resorption. In TMJ sections from the experimental group with overloading, cell-free regions and proteoglycan loss characterized the cartilage degradation; LIPUS exposure restricted these changes in the mandibular condyle. Furthermore, the number of tartrate-resistant acid phosphatase-positive osteoclasts in the mineralized layer of the condylar cartilage increased after mechanical overloading and decreased after LIPUS treatment. Our findings suggest that LIPUS exposure after mechanical TMJ overloading downregulates subchondral trabecular bone resorption and proteoglycan loss in the mandibular condylar cartilage. Thus, it may prove to be protective effects of LIPUS exposure on onset and early progression of TMJ-OA induced by mechanical overloading.

developmental biology

Fast and global detection of periodic sequence repeats in large genomic resources

Periodically repeating DNA and protein elements are involved in various important biological events including genomic evolution, gene regulation, protein complex formation, and immunity. Notably, the currently used genome editing tools such as ZFNs, TALENs, and CRISPRs are also all associated with periodically repeating biomolecules of natural organisms. Despite the biological importance of periodically repeating sequences and the expectation that new genome editing modules could be discovered from such periodical repeats, no software that globally detects such structured elements in large genomic resources in a high-throughput and unsupervised manner has been developed. Here, we developed new software, SPADE (Search for Patterned DNA Elements), that exhaustively explores periodic DNA and protein repeats from large-scale genomic datasets based on k-mer periodicity evaluation. SPADE precisely captured reported genome-editing-associated sequences and other protein families involving repeating domains with significantly better performance than the other software designed for limited sets of repetitive biomolecular sequences.

bioinformatics

Glucocorticoid receptor-mediated amygdalar metaplasticity underlies adaptive modulation of fear memory by stress

Glucocorticoid receptor (GR) is crucial for signaling mediated by stress-induced high levels of glucocorticoids. The lateral nucleus of the amygdala (LA) is a key structure underlying auditory-cued fear conditioning. Here, we demonstrate that genetic disruption of GR in the LA (LAGRKO) resulted in an auditory-cued fear memory deficit for strengthened conditioning. Furthermore, the suppressive effect of a single restraint stress (RS) prior to conditioning on auditory-cued fear memory in floxed GR (control) mice was abolished in LAGRKO mice. Optogenetic induction of long-term depression (LTD) at auditory inputs to the LA reduced auditory-cued fear memory in RS-exposed LAGRKO mice, and in contrast, optogenetic induction of long-term potentiation (LTP) increased auditory-cued fear memory in RS-exposed floxed GR mice. These findings suggest that prior stress suppresses fear conditioning-induced LTP at auditory inputs to the LA in a GR-dependent manner, thereby protecting animals from encoding excessive cued fear memory under stress conditions.

neuroscience