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1.
iScience ; 26(5): 106685, 2023 May 19.
Article En | MEDLINE | ID: mdl-37124420

A 25-year-old patient with a primary immunodeficiency lacking immunoglobulin production experienced a relapse after a 239-day period of persistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Viral genetic sequencing demonstrated that SARS-CoV-2 had evolved during the infection period, with at least five mutations associated with host cellular immune recognition. Among them, the T32I mutation in ORF3a was found to evade recognition by CD4+ T cells. The virus found after relapse showed an increased proliferative capacity in vitro. SARS-CoV-2 may have evolved to evade recognition by CD4+ T cells and increased in its proliferative capacity during the persistent infection, likely leading to relapse. These mutations may further affect viral clearance in hosts with similar types of human leukocyte antigens. The early elimination of SARS-CoV-2 in immunocompromised patients is therefore important not only to improve the condition of patients but also to prevent the emergence of mutants that threaten public health.

2.
J Infect Chemother ; 29(8): 731-743, 2023 Aug.
Article En | MEDLINE | ID: mdl-37116613

The trends and prevalence of antimicrobial susceptibility of pathogens vary by country, region, and time. Long-term regular surveillance is required to investigate trends in the antimicrobial resistance of various isolated bacterial pathogens. We report the results of a nationwide surveillance on the antimicrobial susceptibility of bacterial respiratory pathogens in Japan conducted by the Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology. The isolates were collected from clinical specimens obtained from adult patients who visited a collaborating medical facility between June 2019 and December 2020 and were diagnosed with respiratory tract infections by a physician. Antimicrobial susceptibility testing was performed in a centralized laboratory according to the methods recommended by the Clinical and Laboratory Standards Institute. Susceptibility testing was performed for 932 strains (201 Staphylococcus aureus, 158 Streptococcus pneumoniae, 6 S. pyogenes, 136 Haemophilus influenzae, 127 Moraxella catarrhalis, 141 Klebsiella pneumoniae, and 163 Pseudomonas aeruginosa) collected from 32 facilities in Japan. The proportions of methicillin-resistant S. aureus and penicillin-resistant S. pneumoniae were 35.3% and 0%, respectively. In H. influenzae, 16.2% and 16.9% were ß-lactamase-producing ampicillin resistant and ß-lactamase-negative ampicillin resistant, respectively. Extended-spectrum ß-lactamase-producing K. pneumoniae accounted for 5.0% of all K. pneumoniae infections. Carbapenemase-producing K. pneumoniae and multi-drug-resistant P. aeruginosa with metallo-ß-lactamase were not detected in this study. This surveillance will be a useful reference for treating respiratory infections in Japan and will provide evidence to enhance the appropriate use of antimicrobial agents.


Communicable Diseases , Methicillin-Resistant Staphylococcus aureus , Respiratory Tract Infections , Adult , Humans , Ampicillin , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacteria , beta-Lactamases , Communicable Diseases/drug therapy , Drug Resistance, Bacterial , Haemophilus influenzae , Microbial Sensitivity Tests , Respiratory Tract Infections/drug therapy , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/microbiology , Japan
3.
J Infect Chemother ; 26(9): 873-881, 2020 Sep.
Article En | MEDLINE | ID: mdl-32565151

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by the Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2016. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between February 2016 and August 2016 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standards Institute. Susceptibility testing was evaluated in 1062 strains (143 Staphylococcus aureus, 210 Streptococcus pneumoniae, 17 Streptococcus pyogenes, 248 Haemophilus influenzae, 151 Moraxella catarrhalis, 134 Klebsiella pneumoniae, and 159 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 48.3%, and those of penicillin-susceptible S. pneumoniae was 99.5%. Among H. influenzae, 14.1% of them were found to be ß-lactamase-producing ampicillin-resistant strains, and 41.1% to be ß-lactamase-non-producing ampicillin-resistant strains. Extended spectrum ß-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo ß-lactamase were 4.5% and 0.6%, respectively.


Communicable Diseases , Methicillin-Resistant Staphylococcus aureus , Respiratory Tract Infections , Adult , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Communicable Diseases/drug therapy , Drug Resistance, Bacterial , Haemophilus influenzae , Humans , Japan/epidemiology , Microbial Sensitivity Tests , Respiratory Tract Infections/drug therapy , Respiratory Tract Infections/epidemiology
4.
J Infect Chemother ; 25(9): 657-668, 2019 Sep.
Article En | MEDLINE | ID: mdl-31196772

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2014. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between January 2014 and April 2015 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standards Institute. Susceptibility testing was evaluated in 1534 strains (335 Staphylococcus aureus, 264 Streptococcus pneumoniae, 29 Streptococcus pyogenes, 281 Haemophilus influenzae, 164 Moraxella catarrhalis, 207 Klebsiella pneumoniae, and 254 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 43.6%, and those of penicillin-susceptible S. pneumoniae was 100%. Among H. influenzae, 8.2% of them were found to be ß-lactamase-producing ampicillin-resistant strains, and 49.1% to be ß-lactamase-non-producing ampicillin-resistant strains. Extended spectrum ß-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo ß-lactamase were 9.2% and 0.4%, respectively.


Anti-Bacterial Agents/therapeutic use , Drug Resistance, Bacterial , Epidemiological Monitoring , Respiratory Tract Infections/prevention & control , Antimicrobial Stewardship , Haemophilus influenzae/drug effects , Humans , Japan/epidemiology , Klebsiella pneumoniae/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Moraxella catarrhalis/drug effects , Pseudomonas aeruginosa/drug effects , Respiratory Tract Infections/microbiology , Streptococcus pneumoniae/drug effects , Streptococcus pyogenes/drug effects
5.
Cerebrovasc Dis ; 44(5-6): 325-329, 2017.
Article En | MEDLINE | ID: mdl-29073616

BACKGROUND: Serum 1,5-anhydroglucitol (1,5-AG) levels are a measure that provides information on daily glycemic variations. We evaluated whether 1,5-AG could be a possible marker of acute ischemic stroke (AIS) or transient ischemic attacks (TIA) in patients with diabetes mellitus (DM). METHODS: We retrospectively reviewed electronic medical records of 5,294 AIS/TIA patients. Of the 5,294, 1,898 had diabetes and in 1,246, serum 1,5-AG levels were measured (group S). Group S was divided into 2 subgroups: hemoglobin A1c (HbA1c) <7% (S-low) and >7% (S-high). As controls, 394 outpatients with diabetes (group C) without AIS/TIA were likewise divided into subgroups, C-low and C-high according to HbA1c level. In each HbA1c subgroup, the association between serum 1,5-AG (≥14 vs. <14 µg/mL) and stroke was examined using multivariable logistic regression (MLR) with stepwise variable selection. In model 1, the OR and 95% CI was examined adjusted for age and gender. Known risk factors for stroke; hypertension, dyslipidemia, alcohol consumption, smoking, and estimated glomerular filtration rate were included in model 2. RESULTS: Overall, serum 1,5-AG levels were lower in group S than in group C. Serum 1,5-AG levels were low in subgroups S-high and C-high, showing no differences in mean values. However, mean serum 1,5-AG levels in S-low was statistically lower than that in C-low. MLR analysis showed that the OR for low (<14 µg/mL) 1,5-AG for stroke was statistically significant only in well-controlled diabetes (OR [95% CI] 2.19 [1.54-3.10]) in model 1 and (2.26 [1.56-3.28]) model 2. CONCLUSIONS: Low serum 1,5-AG levels could be a possible marker for AIS/TIA risk in patients with well-controlled DM.


Brain Ischemia/etiology , Deoxyglucose/blood , Diabetes Mellitus/blood , Ischemic Attack, Transient/etiology , Stroke/etiology , Aged , Aged, 80 and over , Biomarkers/blood , Brain Ischemia/blood , Brain Ischemia/diagnosis , Diabetes Mellitus/diagnosis , Diabetes Mellitus/therapy , Down-Regulation , Electronic Health Records , Female , Glycated Hemoglobin/metabolism , Humans , Ischemic Attack, Transient/blood , Ischemic Attack, Transient/diagnosis , Male , Middle Aged , Prognosis , Retrospective Studies , Risk Factors , Stroke/blood , Stroke/diagnosis , Time Factors
6.
Adv Mater ; 21(48): 4996-5000, 2009 Dec 28.
Article En | MEDLINE | ID: mdl-25376650

Suppression of nucleation around a gold electrode during pentacene growth on a SiO2 channel is found by photoemission electron microscopy. Mass flow is driven by the difference between the molecular orientations on SiO2 and gold. The poor connectivity at the channel/electrode boundary causes degradation in the performance of a field-effect transistor, which is found to be improved by self-assembled monolayer treatment on the electrode (see figure; thickness in monolayers (ML)).

7.
Phys Rev Lett ; 94(8): 086105, 2005 Mar 04.
Article En | MEDLINE | ID: mdl-15783909

The structure and stability of the hydrogen-terminated (105) surface of Ge deposited on Si(105) substrates are investigated by scanning tunneling microscopy (STM). Investigations combining STM, electron energy loss spectroscopy, and theory reveal that Si incorporation into the surface Ge layer of hydrogen-terminated Ge/Si(105) drastically destabilizes the surface. The STM images obtained on this surface are well explained by the recently established rebonded-step structure model.

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