Publications by authors named "Namkoong H"
Objectives: Severe acute respiratory syndrome coronavirus 2 significantly impacts Japan with a high number of infections and deaths reported. Long coronavirus disease (COVID) characterised by persistent symptoms after COVID-19 has gained recognition but varies across studies. This study aimed to investigate the differences in long COVID among patients hospitalised during Japan's first three waves of the pandemic.
View Article and Find Full Text PDFObjectives: We examined shifts in labor productivity and their economic ramifications among adult patients with long COVID in Japan.
Methods: A total of 396 patients were categorized into three groups based on symptom progression: non-long COVID, long COVID recovered, and long COVID persistent. Patient-reported outcomes were assessed at three time intervals: 3, 6, and 12 months after COVID-19 diagnosis.
Sectm1a Depletion Promotes Neutrophil Recruitment during Pneumococcal Pneumonia.
Am J Respir Cell Mol Biol
December 2024
Airway epithelial cells (AECs) play an essential role in the immune response during bacterial pneumonia. Secreted and transmembrane 1a (Sectm1a) is specifically expressed in AECs during early (SP) infection. However, its function remains largely unexplored.
View Article and Find Full Text PDFPurpose: Mycobacterial liquid culturing typically requires six weeks or longer, primarily because of the slow growth rate of Mycobacterium tuberculosis. This study aimed to evaluate the potential of shortening the duration of mycobacterial liquid culturing in healthcare settings with high prevalence rates of non-tuberculous mycobacteria.
Methods: We retrospectively analyzed the relationship between mycobacterial species and time to positive testing of liquid cultures from sputum samples using the Mycobacteria Growth Indicator Tube system over a 3.
Article Synopsis
- The study aimed to explore how serum ferritin and KL-6 levels can predict severe outcomes in COVID-19 patients, like death or needing intensive care.
- Data from nearly 2,500 patients showed that different combinations of these markers were linked to different patient profiles and mortality rates.
- Notably, using both markers together was better at predicting critical outcomes than using either marker on its own.
Article Synopsis
- Cutis laxa is a group of connective tissue diseases that can be inherited or acquired, leading to loose skin and potential lung complications, though the specifics of pulmonary issues are not well understood.
- A 36-year-old woman with a lifelong diagnosis of cutis laxa showed severe lung impairment and unusual pulmonary function test results, along with abnormal CT scan findings but no typical signs of emphysema.
- Genetic analysis revealed a variant in the elastin gene linked to her pulmonary issues, and over eight years, her lung function continued to decline despite stable CT images, indicating progressive small airway disease.
Article Synopsis
- This study investigates the factors contributing to prolonged dyspnea (difficulty breathing) in patients recovering from COVID-19, known as long COVID.
- It involved a multicenter cohort from 26 medical institutions in Japan, analyzing clinical data and patient-reported outcomes over 3, 6, and 12 months.
- Key findings indicate that chronic obstructive pulmonary disease (COPD), asthma, and the use of mechanical ventilation are significant risk factors for experiencing prolonged dyspnea in these patients.
Article Synopsis
- The study investigates how genetic factors regulate protein expression using protein quantitative trait loci (pQTLs) and highlights differences from traditional mRNA expression studies (eQTLs).
- Analyzing data from over 4,000 samples, researchers found that fine-mapped pQTLs are linked to missense variants and show distinct mechanisms from eQTLs, indicating different regulatory influences.
- The research reveals a negative correlation between ABO gene mRNA and protein levels due to genetic linkage, showcasing the complexities in the relationship between these expression types.
Article Synopsis
- * There were 32 patients with NTM-PPFE included, who showed a lower body mass index and higher initiation rates for NTM therapy compared to other types; however, they experienced more treatment-related side effects and had poorer treatment success rates.
- * The findings indicated that NTM-PPFE is a distinct type of NTM-PD associated with a significantly worse prognosis
Article Synopsis
- Researchers created a tool called scLinaX to measure gene expression from the inactivated X chromosome using single-cell RNA sequencing data.
- Their analysis found that lymphocytes (a type of immune cell) show a stronger escape from X chromosome inactivation compared to myeloid cells (another type of immune cell).
- The study revealed significant differences in XCI escape across various tissues and cell types, emphasizing the complex relationship between genetics and phenotype in different sexes.
Article Synopsis
- A 68-year-old woman with asthma and nontuberculous mycobacterial-pulmonary disease (NTM-PD) developed fever and wheezing, leading to a diagnosis of allergic bronchopulmonary aspergillosis (ABPA).
- ABPA was identified through lab tests showing elevated eosinophils and specific IgE levels, alongside imaging that revealed mucus plugging.
- Dupilumab, an IL-4/13 blocker, was administered instead of systemic prednisolone to avoid worsening NTM-PD, and the paper discusses the associated pathophysiological mechanisms of this rare condition.
Social impact of brain fog and analysis of risk factors: Long COVID in Japanese population.
Ann Clin Transl Neurol
August 2024
Article Synopsis
- This study investigates brain fog in COVID-19 patients, focusing on its clinical features and societal impact, particularly on work productivity.
- A cohort of 1,009 hospitalized patients was analyzed, revealing that brain fog symptoms decreased after 3 months but remained stable up to 12 months, with certain neurological symptoms correlating to higher brain fog instances.
- Key risk factors were identified, including advanced age, female sex, obesity, and pre-existing respiratory issues, with findings indicating that brain fog negatively affects labor productivity.
Background: Renal impairment is a predictor of coronavirus disease (COVID-19) severity. No studies have compared COVID-19 outcomes in patients with chronic kidney disease (CKD) and patients with impaired renal function without a prior diagnosis of CKD. This study aimed to identify the impact of pre-existing impaired renal function without CKD on COVID-19 outcomes.
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- The latest guidelines for treating complex pulmonary disease recommend using azithromycin, but there’s limited data on its effectiveness against specific strains of the pathogen (MAC).
- A study conducted on 318 MAC strains from a Japanese center showed that azithromycin generally has higher minimum inhibitory concentrations (MICs) than clarithromycin, which raises concerns about relying on clarithromycin's susceptibility results to predict azithromycin effectiveness.
- The findings suggest the need for more extensive multicenter studies to better understand azithromycin's MIC distribution and its relationship to treatment outcomes, as this study had a small sample size and limited treatment outcomes.
Background: No comprehensive analysis of the pulmonary sequelae of coronavirus disease 2019 (COVID-19) in Japan based on respiratory function tests and chest computed tomography (CT) has been reported. We evaluated post-COVID-19 conditions, especially focusing on pulmonary sequelae assessed by pulmonary function tests and chest CT.
Methods: For this prospective cohort study, we enrolled 1069 patients who presented pneumonia at the time of admission in 55 hospitals from February 2020 to September 2021.
Article Synopsis
- - This study investigated how CT scans measuring lung volume can predict serious outcomes in hospitalized COVID-19 patients, using data from 1,200 patients in 4 hospitals and employing AI to assess lung fields.
- - Results showed that patients with lower predicted total lung volume (TLC) had significantly higher rates of critical complications like bacterial infections and heart failure compared to those with higher volumes (14.2% vs 3.3%).
- - The study concluded that lower lung volume on CT scans is linked to worse outcomes and slower recovery in COVID-19 patients, highlighting its potential as a prognostic tool in clinical settings.
The enteric nervous system (ENS) is contained within two layers of the gut wall and is made up of neurons, immune cells, and enteric glia cells (EGCs) that regulate gastrointestinal (GI) function. EGCs in both inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) change in response to inflammation, referred to as reactive gliosis. Whether EGCs restricted to a specific layer or region within the GI tract alone can influence intestinal immune response is unknown.
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- Low Hounsfield unit values from vertebral bone CT scans indicate low bone mineral density (BMD), which is a risk factor for osteoporosis and potentially affects COVID-19 outcomes.
- A study examined 1,132 Japanese COVID-19 inpatients to see how low BMD relates to severe clinical outcomes, finding that patients with low BMD experienced more critical outcomes, especially during the first four waves of COVID-19.
- The research revealed that patients requiring oxygen during hospitalization had a significant decrease in BMD over three months, suggesting that low BMD can help predict severe disease in COVID-19 patients and may worsen over time.
Article Synopsis
- A study aimed to identify what motivates individuals to receive COVID-19 booster vaccines through a paper-based questionnaire at Keio University, involving 1725 participants who had received their initial vaccinations in 2021.
- The main motivators for getting vaccinated included fear of severe illness from COVID-19 (72.6%), concern about infecting others (68.4%), and fear of infection itself (68.3%).
- Television was found to be the most influential source of vaccination information, while trust in vaccine efficacy and safety was linked to participants' willingness to get booster shots, regardless of reported adverse events experienced.
Background: Dialysis patients are susceptible to developing severe coronavirus disease 2019 (COVID-19) due to hypoimmunity. Antibody titers against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) after the primary vaccinations are lower in hemodialysis (HD) patients than in healthy individuals. This study aimed to evaluate the effect of a SARS-CoV-2 booster vaccination in HD and peritoneal dialysis (PD) patients based on antibody titers and cellular and humoral immunity.
View Article and Find Full Text PDFObjective: This study aimed to investigate the clinical features of long COVID cases presenting with upper respiratory symptoms, a topic not yet fully elucidated.
Study Design: Prospective cohort study.
Setting: A multicenter study involving 26 medical facilities in Japan.
Article Synopsis
- - The study investigates long COVID symptoms among 935 patients in Japan, categorizing them into five distinct clusters based on various symptom presentations and their impact on quality of life (QOL).
- - The clusters include: numerous symptoms affecting multiple organs, minimal symptoms, taste and smell disorders, fatigue with psychological symptoms, and fatigue with respiratory issues, showcasing a diverse range of long COVID experiences.
- - Findings highlight the need for personalized treatment approaches, as the severely affected patients (mostly elderly in cluster 1) experienced the greatest decline in QOL, while other clusters showed different symptom trends and demographic profiles.
Article Synopsis
- Muscle quantification via chest CT is shown to be a promising prognostic indicator for COVID-19 outcomes, focusing particularly on pectoralis and erector spinae muscles.
- A study involving 1410 COVID-19 patients revealed that lower muscle density, especially in the erector spinae, correlates with more severe disease and poorer outcomes, regardless of sex.
- Patients with low CT density in both muscle groups (Group D) faced significantly worse clinical outcomes compared to those with high density (Group A), highlighting the importance of these muscle parameters in assessing prognosis.