Publications by authors named "Norihiko Takemoto"
Clinical isolates of Streptococcus pyogenes are usually classified using emm and multilocus sequence typing (MLST). Recently, whole genome sequencing (WGS) has been employed for emm typing and MLST analysis. WGS data provides additional information on the presence of virulence factor genes.
View Article and Find Full Text PDFControlling the carbon flux is important for efficient production of value-added chemicals using microbial cell factories. In this study, we developed a system to control the carbon flux in Corynebacterium glutamicum via targeted protein degradation. We employed an SspB-dependent protein degradation system targeting the SsrA tag and applied it to control the carbon flux.
View Article and Find Full Text PDFChanges in swallowing response on patients undergoing chemoradiotherapy for head and neck cancer.
Nao Hashida
,
Motoyuki Suzuki
,
Kiyohito Hosokawa
,
Yukinori Takenaka
,
Takahito Fukusumi
,
Norihiko Takemoto
Support Care Cancer
January 2025
Purpose: Chemoradiotherapy (CRT) for head and neck cancer (HNC) often causes dysphagia. The risk of dysphagia increases during CRT tends to become more severe after finishing CRT, and persists for a few weeks thereafter. Thus, understanding the changes in swallowing physiology during and immediately after CRT is essential.
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- Streptococcal toxic shock syndrome (STSS) is a severe condition mainly caused by beta-hemolytic streptococci (BHS), with the study investigating other BHS species' roles in STSS development.
- The study analyzed medical records from 2002 to 2022, identifying 43 STSS cases and examining their clinical features compared to 285 non-STSS cases, while factoring in age and diabetes.
- Results showed a high mortality rate of about 35% in STSS cases, with certain BHS species being more strongly associated with STSS than others, highlighting the need for further understanding of these infections.
Article Synopsis
- Endotoxins (LPS) are problematic in bacterial protein production, but researchers developed a method using a special bacterium that lacks LPS.
- They successfully created endotoxin-free proteins, including functional green fluorescent protein and the cytokine TNF-α, and significantly reduced contamination levels.
- This new system also enabled the production of a specific antibody targeting the coronavirus spike protein and a rheumatoid arthritis drug, showcasing its potential for future applications in biotechnology.
Comparison of the effects of cefmetazole and meropenem on microbiome: A pilot study.
J Infect Chemother
December 2024
Article Synopsis
- Cefmetazole (CMZ) is being studied as an alternative treatment for infections caused by ESBL-producing bacteria, with this pilot study comparing its effects to meropenem (MP) and a control group with no treatment.
- The study involved collecting feces and saliva samples from patients at different time points to analyze changes in their microbiome due to the antimicrobial treatments.
- Results indicated that meropenem had a more significant negative impact on the fecal microbiome compared to CMZ, especially in the later stages of treatment among Japanese patients.
Article Synopsis
- The study focuses on understanding the function of the PmrAB two-component system (TCS) in resistance to colistin, a last-resort antibiotic, in extensively drug-resistant (XDR) Gram-negative bacteria.
- Researchers conducted transcriptome analysis to identify the regulatory genes controlled by PmrAB, revealing its responsiveness to environmental factors like pH and metal ions (Fe, Zn, Al).
- The findings highlight PmrAB's role in both environmental adaptation and the development of antibiotic resistance by modifying lipooligosaccharide (LOS) to mitigate toxicity and enhance resistance to colistin and polymyxin B.
Article Synopsis
- * Out of the eight scoring systems, the MD Anderson Cancer Center + neutrophil-to-lymphocyte ratio showed the best ability to predict response and disease control, while the Hammersmith score excelled at predicting overall survival, particularly after 3 months.
- * Overall, all eight scoring systems were found to be prognostic factors for overall survival, highlighting their importance in assessing patient outcomes in this specific cancer type.
Immune checkpoint inhibitors (ICIs) are indicated for a diverse range of cancer types, and characterizing the tumor immune microenvironment is critical for optimizing therapeutic strategies, including ICIs. T cell infiltration and activation status in the tumor microenvironment greatly affects the efficacy of ICIs. Here, we show that semaphorin 6D (Sema6D) forward signaling, which is reportedly involved in coordinating the orientation of cell development and migration as a guidance factor, impaired the infiltration and activation of tumor-specific CD8+ T cells in murine oral tumors.
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- Patients with head and neck squamous cell cancer (HNSCC) often experience malnutrition, which may affect their response to immune checkpoint inhibitor (ICI) treatments.
- A study analyzed the prognostic value of nutritional indices, specifically BMI, GNRI, and PNI, among 106 HNSCC patients treated with ICIs from 2017 to 2022.
- Results showed that the prognostic nutritional index (PNI) significantly predicted progression-free survival (PFS) and overall survival (OS), suggesting it should be considered when determining ICI treatment plans.
A multilocus sequence typing method of Staphylococcus aureus DNAs in a sample from human skin.
Microbiol Immunol
October 2023
The skin and mucous membranes are the primary sites of Staphylococcus aureus colonization, particularly those of health care personnel and patients in long-term care centers. We found that S. aureus colonized with a higher abundance ratio on skins which had recovered from pressure injury (PI) than on normal skins in our earlier research on the skin microbiota of bedridden patients.
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- Immune checkpoint inhibitors (ICIs) have transformed cancer treatment, but many patients still show low response rates, presenting ongoing challenges.
- The study found that Sema4A-positive non-small cell lung cancer (NSCLC) patients had a significantly better response to anti-PD-1 therapy compared to those who were Sema4A-negative.
- Sema4A enhances T cell activation and prevents T cell exhaustion in NSCLC, making it a potential target for improving ICI treatments and a useful biomarker for predicting patient response.
Article Synopsis
- Head and neck squamous cell carcinoma (HNSCC) with distant metastasis (DM) generally has a poor prognosis, with different histological variants showing varying DM rates and outcomes.
- A study analyzed data from over 54,000 cases to compare DM rates and overall survival (OS) across different HNSCC types, finding that basaloid squamous cell carcinoma had the highest DM rate (9.4%) and verrucous carcinoma had the lowest (0.2%).
- Notably, spindle cell carcinoma (SpCC) showed a significant association with poor OS, indicating that metastasis in this variant leads to worse health outcomes compared to other HNSCC types.
Article Synopsis
- The study investigates whether circulating tumor HPV16 DNA (ctHPV16DNA) can predict treatment outcomes for patients with advanced HPV16-related oropharyngeal cancer undergoing radiation therapy.
- Researchers collected blood samples from 22 patients during treatment and found that patients with a slow clearance of ctHPV16DNA had a higher risk of treatment failure, with 100% failure risk after 60 Gy of radiation.
- The findings suggest that monitoring ctHPV16DNA levels can aid in identifying patients who may need more intensive treatment based on their clearance profile, indicating potential improved survival rates for those with rapid clearance.
Early-stage glottic cancer of rare squamous cell carcinoma variants: a population-based study.
Acta Otolaryngol
January 2023
Article Synopsis
- - Squamous cell carcinoma (SCC) is the primary type of laryngeal cancer, with various subtypes that may require different treatment approaches, although more research is needed to clarify their distinctions.
- - A study analyzing data from over 12,000 cases focused on early-stage glottic cancer found substantial differences in survival rates among SCC variants using statistical models.
- - The results indicated that most SCC variants, except for adenosquamous SCC, have similar prognosis levels to conventional SCC, with significant outcomes noted specifically in conventional and papillary SCC treatments.
Article Synopsis
- Verrucous carcinoma (VC) is a rare type of squamous cell carcinoma that is often thought to resist radiation therapy, but this study aimed to provide clearer evidence on its treatment outcomes.
- Researchers analyzed data from the SEER database, comparing overall survival (OS) and disease-specific survival (DSS) rates in patients treated with surgery versus radiation while minimizing bias in treatment selection.
- Their findings indicated that the five-year OS and DSS rates were similar for both treatment groups, suggesting that radiation therapy could be an effective option for VC.
Article Synopsis
- * This study examined how colistin-resistant A. baumannii strains arise, showing that while colistin alone leads to LPS-deficient strains, combining it with other antibiotics results in strains with modified LPS.
- * The findings indicate that LPS-deficient strains are less fit and more susceptible to other treatments, suggesting that LPS-modified strains are more prevalent in clinical settings, highlighting the urgent need to address colistin resistance in healthcare.
Article Synopsis
- The radiation recall phenomenon (RRP) is a rare complication that can occur after radiation therapy, sometimes triggered by treatments like anticancer drugs or COVID-19 vaccines.
- A case study involving a 50-year-old woman showed that after her larynx radiation therapy and treatment with ramucirumab, she experienced RRP, characterized by symptoms like sore throat and mucosal bleeding.
- After receiving the Pfizer-BioNTech COVID-19 vaccine, her symptoms worsened, leading to hospitalization and steroid treatment, highlighting the need to consider RRP as a potential risk when administering vaccines to patients with a history of radiation therapy.
Article Synopsis
- Researchers conducted a genome-wide association study (GWAS) with 2,393 COVID-19 patients and 3,289 controls in Japan, identifying a specific genetic variant (rs60200309-A) on chromosome 5 linked to severe cases in individuals under 65.
- The variant is more common in East Asians and associated with reduced expression of the DOCK2 gene, which was found to be lower in severe COVID-19 cases, particularly in non-classical monocytes.
- Additionally, inhibiting DOCK2 in hamsters worsened pneumonia symptoms, indicating its potential as a biomarker and therapeutic target for severe COVID-19.
Article Synopsis
- This study evaluated whether body composition metrics, like skeletal muscle index (SMI) and visceral adipose index (VAI), can predict treatment responses in patients with head and neck squamous cell carcinoma (HNSCC) undergoing nivolumab therapy.
- A review of 114 patients revealed that low SMI and low VAI were linked to worse disease control and treatment response; low SMI was specifically associated with poorer overall and progression-free survival.
- The findings suggest assessing body composition indices prior to starting nivolumab could help identify patients who might benefit most from the treatment.
Article Synopsis
- The study examined the significance of the neutrophil-to-lymphocyte ratio (NLR) in predicting outcomes for patients with head and neck squamous cell carcinoma (HNSCC) receiving immune checkpoint inhibitors (ICIs).
- Researchers reviewed various studies, focusing on how NLR relates to overall and progression-free survival, as well as treatment response and disease control among 929 patients.
- Findings revealed that a higher NLR is linked to worse outcomes, indicating that NLR can serve as a predictor of treatment efficacy in HNSCC patients treated with ICIs.
Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) has become a serious epidemiologic problem worldwide. In this study, we aimed to investigate recently isolated MRSA types and determine their characteristics.
Methods: We collected 164 strains isolated from 13 hospitals located in Tokyo and surrounding prefectures.
Article Synopsis
- The study aimed to assess how sarcopenia impacts the survival outcomes of patients with head and neck cancer, comparing those treated with surgery versus radiation.
- A meta-analysis of 18 studies showed that sarcopenia significantly worsens overall survival, disease-free survival, and disease-specific survival in both treatment groups, with more pronounced effects in the surgery group.
- The findings highlight that evaluating sarcopenia is crucial for making informed treatment decisions in head and neck cancer patients.
Article Synopsis
- A study examined the effectiveness of HPV DNA and mRNA from oral gargle samples and circulating tumor HPV16 DNA (ctHPV16DNA) from blood in detecting HPV-related oropharyngeal cancer (OPC) and cancer of unknown primary (CUP).
- The results showed high sensitivity and specificity for ctHPV16DNA in OPC cases, outperforming oral biomarkers, although the difference wasn't statistically significant.
- ctHPV16DNA also demonstrated a strong correlation with disease extent and tumor characteristics, indicating its potential as a biomarker for HPV16-related OPC, but more research is needed for CUP.