Publications by authors named "Takashi Nemoto"

Background: Dexamethasone is currently administered for Coronavirus disease 2019(COVID-19); however, there are concerns about its effect on specific antibodies' production. The aim of this study was to evaluate whether specific antibodies were affected by COVID-19 severity and corticosteroid treatment.

Methods: Of 251 confirmed COVID-19 patients admitted to our hospital between January 26 and August 10, 2020, the early period of the pandemic, 75 patients with sera within 1 month of onset and 1 month or longer were included in the research.

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16S rRNA gene amplicon sequencing analysis is used to investigate bacterial communities; however, the estimated bacterial composition can differ from the original due to experimental and analytical biases. Therefore, this study determines the optimal conditions to minimize the potential biases in 16S rRNA gene amplicon sequencing analysis using different DNA samples, trimming lengths, primers, and databases. The results of the mock1 community with 250 and 300 bp paired-end (PE), comprising 15 bacteria from various environments, showed the highest similarity between the theoretical value and the data using the Greengenes2 and the V3 region at the genus level and V5-V6 at the species level.

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Background: Data are limited on the protective role of the Omicron BA bivalent vaccine, previous infection, and their induced neutralizing antibodies against Omicron XBB.1.16 and EG.

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Background: We aimed to examine the association among nucleocapsid (N) antibodies, a combination of N and spike (S) antibodies, and protection against SARS-CoV-2 reinfection.

Methods: We conducted a prospective cohort study among staff at a national medical research center in Tokyo and followed them for the incidence of SARS-CoV-2 infection between June and September 2023 (Omicron XBB.1.

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Background & Aims: Vitamin D deficiency is a common nutritional problem worldwide that may have worsened during the coronavirus disease 2019 (COVID-19) pandemic. The present study sought to examine the prevalence and correlates of vitamin D deficiency among healthcare workers three years after the start of the COVID-19 pandemic.

Methods: Participants comprised 2543 staff members from a medical research institute, who completed a questionnaire and donated blood samples in June 2023.

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Article Synopsis
  • - This study explores the effectiveness of antibody testing for assessing immunity and diagnosing conditions like multisystem inflammatory syndrome related to COVID-19, focusing on antibodies targeting the SARS-CoV-2 spike protein.
  • - Researchers measured the neutralizing activity of immunoglobulin-G (IgG) in COVID-19 convalescent patients, finding a strong correlation between serum neutralizing activity (IgG-EC) and specific antibodies (S-IgG).
  • - The findings suggest that quantitative S-IgG tests can reliably estimate neutralizing antibody activity, provided the cut-off values for interpreting results are carefully established for accuracy.
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Background: In recent years, light has been used for bacterial control of periodontal diseases. This in vitro study evaluated the effects of light-emitting diode (LED) irradiation at different wavelengths on both Porphyromonas gingivalis and human gingival fibroblasts (HGF-1).

Methods: P.

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Background: Data are limited on the role of preinfection humoral immunity protection against Omicron BA.5 infection and long coronavirus disease (COVID) development.

Methods: We conducted nested case-control analysis among tertiary hospital staff in Tokyo who donated blood samples in June 2022 (1 month before Omicron BA.

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Objective: This study aimed to evaluate the in vitro antibacterial effects of lysozyme-chitosan oligosaccharide conjugates (LYZOX) against Streptococcus gordonii and Porphyromonas gingivalis.

Materials And Methods: Planktonic S. gordonii and P.

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The optimal method for decontamination of implant surfaces for peri-implantitis treatment remains controversial. In recent years, erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation and implantoplasty (IP) (i.e.

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Objectives: To examine the differences in durability and its determinants of humoral immunity following 2- and 3-dose COVID-19 vaccination.

Methods: Throughout the pandemic, we evaluated the anti-spike IgG antibody titers of 2- and 3-dose mRNA vaccine recipients over time among the staff of a medical and research center in Tokyo. Linear mixed models were used to estimate trajectories of antibody titers from 14 to 180 days after the last immune-conferred event (vaccination or infection) and compare antibody waning rates across prior infection and vaccination status, and across background factors in infection-naïve participants.

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Background: Amoxicillin plus probenecid is an alternative to intramuscular benzathine penicillin G for treating syphilis in the United Kingdom. Low-dose amoxicillin is an alternative treatment option used in Japan.

Methods: We conducted an open-label, randomized, controlled, non-inferiority trial between 31 August 2018, and 3 February 2022, to compare 1500 mg low-dose amoxicillin monotherapy with the combination of 3000 mg amoxicillin and probenecid (non-inferiority margin 10%).

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To describe the trend of cumulative incidence of coronavirus disease 19 (COVID-19) and undiagnosed cases over the pandemic through the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants among healthcare workers in Tokyo, we analysed data of repeated serological surveys and in-house COVID-19 registry among the staff of National Center for Global Health and Medicine. Participants were asked to donate venous blood and complete a survey questionnaire about COVID-19 diagnosis and vaccine. Positive serology was defined as being positive on Roche or Abbott assay against SARS-CoV-2 nucleocapsid protein, and cumulative infection was defined as either being seropositive or having a history of COVID-19.

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High-angle annular dark-field (HAADF) imaging and elemental mapping at the atomic scale by scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS) are widely used for material characterization, in which quantitative understanding of the contrast of the image is required. Here, we report an unexpected image contrast in the elemental mapping of rutile TiO2, where the Ti L2,3 map shows an anisotropic elliptical shape that extends along the long axis in the octahedral structure, while the atomic contrast of Ti columns in the HAADF image is almost circular. Multi-slice simulation reveals that unique electron channeling related to the rutile structure and the difference of the potentials between HAADF and EELS cause the different atomic contrasts in the two images.

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This multicenter, preliminary, randomized controlled trial investigated the effect of a tailored fall-prevention program using home floor plans for discharged orthopedic patients aged ≥65 years who experienced ≥1 fall(s) in the past year ( = 72) at five acute-care hospitals. The control group received standard care (exercise to prevent recurrent falls), whereas the intervention group received a tailored fall-prevention program in addition to usual care. A physical therapist conducted the tailored education program using each patient's home floor plans before discharge.

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The number of complications related to dental implants has been increasing, as implant therapy has grown to become the most popular treatment choice for replacing missing teeth. Various cases of implant complications have been reported, particularly biologic complications caused by inadequate surgical techniques, including malpositioned implants, that are difficult to solve. In the present case, two malpositioned implants with peri-implantitis were placed in the maxillary right first molar area of a 64-year-old woman.

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Article Synopsis
  • Periodontal disease starts with gingivitis (inflammation of the gum) and can progress to periodontitis, which leads to tooth loss due to a polymicrobial infection.
  • Research aimed to analyze the differences in bacterial composition and metabolic activity in healthy, gingivitis, and periodontitis states using samples from 21 patients.
  • Results indicated that bacterial networks became more complex during gingivitis but less so as the disease progressed to periodontitis, highlighting specific bacteria that are linked to disease progression and the impact of the periodontal microbiome on oral health.
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Ancient dental calculus, formed from dental plaque, is a rich source of ancient DNA and can provide information regarding the food and oral microbiology at that time. Genomic analysis of dental calculus from Neanderthals has revealed the difference in bacterial composition of oral microbiome between Neanderthals and modern humans. There are few reports investigating whether the pathogenic bacteria of periodontitis, a polymicrobial disease induced in response to the accumulation of dental plaque, were different between ancient and modern humans.

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The aim of this report is to show that periodontitis and peri-implantitis with horizontal bone resorption in a 68-year-old male patient were successfully treated by non-surgical treatment. Scaling with an ultrasonic device was performed for moderate periodontitis around the mandibular left first premolar and moderate peri-implantitis around the maxillary right molar implants. Root planing with a metal curette was performed for the periodontal site, and debridement with a plastic curette was performed for the peri-implant site.

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Background And Objective: Dysbiosis, a loss of balance in the microbiota, is a potential factor of peri-implantitis. However, compositional change of the peri-implant microbiota soon after implant uncovering is still unknown. In this study, bacterial composition in the peri-implant sulcus was examined to understand the establishment of bacterial composition within the peri-implant microbiota during the earliest weeks after implant uncovering.

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Peri-implantitis and periodontitis are both polymicrobial diseases induced by subgingival plaque accumulation, with some differing clinical features. Studies on the microbial and gene transcription activity of peri-implantitis microbiota are limited. This study aimed to verify the hypothesis that disease-specific microbial and gene transcription activity lead to disease-specific clinical features, using an integrated metagenomic, metatranscriptomic, and network analysis.

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Introduction: This study aimed to investigate the effects of a new antimicrobial photodynamic therapy (aPDT) system using yellow-green light-emitting diode (YGL) and rose bengal (RB) on Porphyromonas gingivalis (Pg) in vitro.

Materials And Methods: Pg suspension mixed with RB was irradiated with YGL (565 nm) or blue light-emitting diode (BL, 470 nm) at 428 mW/cm in comparison with chlorhexidine (CHG) treatment. The cells were cultured anaerobically on agar plates, and the number of colony-forming units (CFU) was determined.

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