Keita Iyama

Dr. Keita Iyama

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Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2017 in Thyroid®
Verified
Journal Article
Closed access
KIKeita Iyama
Keita Iyama
MMMichiko Matsuse
Michiko Matsuse
NMNorisato Mitsutake
Norisato Mitsutake
TRTatiana Rogounovitch
Tatiana Rogounovitch
VSVladimir Saenko
Vladimir Saenko
SYShunichi Yamashita
Shunichi Yamashita
Background: The BRAFV600E mutation is the most frequent genetic abnormality in adult papillary thyroid carcinomas (PTCs). On the other hand, various chromosomal rearrangements are more prevalent in childhood and adolescent PTCs. The aim of the present study was to identify novel rearrangements in PTCs from young patients. Methods: Among 63 postoperative specimens of childhood and adolescent PTCs, which had been discovered by the thyroid ultrasound screening program in Fukushima, nine samples without prevalent known oncogenes, BRAFV600E, RAS, RET/PTC1, RET/PTC3, and ETV6/NTRK3, were analyzed in the current study by quantitative real-time reverse transcription polymerase chain reaction to screen for novel fusion genes by comparing transcript expression between extracellular and kinase domains of ALK, NTRK1, NTRK3, and RET. Results: Of the above nine samples, five samples were suspected to harbor a fusion, and using subsequent 5′ rapid amplification of cDNA end (RACE), two already reported fusion oncogenes, STRN/ALK and TPR/NTRK1, and three novel fusions, SQSTM1/NTRK3, AFAP1L2/RET, and PPFIBP2/RET, were identified. Functional analyses of these three chimeric genes were performed, and their transforming abilities were confirmed through the activation of mitogen-activated protein kinase (MAPK). Conclusions: Three novel fusion oncogenes have been identified in young PTC patients in Fukushima, suggesting that rare fusions may be present among the cases negative for known oncogenes in this age group and that such rearrangements can play a significant role in thyroid carcinogenesis.

25 July 2024 in Circulation Journal
Verified
Journal Article
Open access
PDF file
MYMakoto Yokoyama
Makoto Yokoyama
KIKeita Iyama
Keita Iyama
THTomoharu Honda
Tomoharu Honda
KMKenichiro Maekawa
Kenichiro Maekawa
KBKensho Baba
Kensho Baba
OTOsamu Tasaki
Osamu Tasaki
Background: Early intervention in prehospital settings is important for treating patients with acute coronary syndrome (ACS). Emergency medical technicians (EMTs) are the essential first responders who treat these patients, and their current attitudes towards electrocardiograms (ECGs) have not been identified. This study investigated the awareness of EMTs of ECGs to shorten hospital arrival time, improving patient prognosis.Methods and Results: An anonymous questionnaire survey, with 27 statements about ECG and ACS response, was administered to 395 EMTs. The statements were related to interest, motivation, learning status, confidence, and norms pertaining to ECGs, a sense of perceived behavioral control, and training courses. The primary outcome was the perception of EMTs that their interpretation of an ECG affected patient prognosis (Statement [S] 1). Participants assigned scores for each statement using a scale ranging from 1 (strongly disagree) to 10 (strongly agree). The mean score for S1 was 7.09. Mean scores for statements regarding confidence and learning status were 3.96 and 3.53, respectively. The participants had a positive impression of training courses (score >5.5).Conclusions: The EMTs experience was that their interpretation of an ECG could affect the prognosis of patients with ACS. Conversely, they lacked confidence reading ECGs, but were willing to attend ECG training courses. Therefore, efficient training programs need to be established to achieve a better prognosis for ACS patients.

KIKeita Iyama
Keita Iyama
TKTakeyasu Kakamu
Takeyasu Kakamu
KYKazunori Yamashita
Kazunori Yamashita
YSYoshinobu Sato
Yoshinobu Sato
JSJiro Shimada
Jiro Shimada
AHArifumi HASEGAWA
Arifumi HASEGAWA
To ensure human resource availability for a smooth response during various types of disasters, there is a need to improve the intent of those involved in responding to each hazard type. However, Disaster Medical Assistance Team personnel’s intent to engage with specific hazards has yet to be clarified. This study therefore aimed to clarify the factors affecting Disaster Medical Assistance Team members’ (n = 178) intent to engage with each type of hazard through an anonymous web questionnaire survey containing 20 questions. Our results show that the intent to engage in disaster response activities was significantly lower for chemical (50), biological (47), radiological/nuclear (58), and explosive (52) incidents compared with natural (82) and man-made hazards (82) (p < 0.01). Multiple regression analysis showed that incentives were the most common factor affecting responders’ intent to engage with all hazard types, followed by self-confidence. Thus, creating a system that provides generous incentives could effectively improve disaster responders’ intent to engage with specific hazards. Another approach could be education and training to increase disaster responders’ confidence. We believe that the successful implementation of these measures would improve the intent of responders to engage with hazards and promote the recruitment of sufficient human resources.

13 September 2016 in Acute Medicine & Surgery
Verified
Journal Article
Open access
PDF file
KIKeita Iyama
Keita Iyama
TUTomohiro Ueki
Tomohiro Ueki
SYShuhei Yamano
Shuhei Yamano
GTGoro Tajima
Goro Tajima
TITakamitsu Inokuma
Takamitsu Inokuma
OTOsamu Tasaki
Osamu Tasaki
Case: A 61‐year‐old man who was hospitalized with schizophrenia in a psychiatric hospital drank hot water estimated to be 90°C. Eight hours after injury, laryngopharynx edema gradually progressed, and his breathing deteriorated. Upon arrival at our emergency room, we secured his respiratory tract by nasal intubation under a bronchoscope.Outcome: The edema gradually improved after peaking at hospital day 2, and he was extubated on hospital day 18. There were no apparent respiratory or esophageal problems, and he was discharged back to the psychiatric hospital on day 28.Conclusion: These types of laryngopharynx burns caused by ingesting hot foods or drinks have been rarely reported for adults. In cases of adults, when the patient is in a special situation such as having a psychiatric disorder, it is necessary to assume that the laryngopharynx burns might be aggravated.

18 October 2021 in Prehospital and Disaster Medicine
Verified
Journal Article
Open access
PDF file
KIKeita Iyama
Keita Iyama
TKTakeyasu Kakamu
Takeyasu Kakamu
KYKazunori Yamashita
Kazunori Yamashita
JSJiro Shimada
Jiro Shimada
OTOsamu Tasaki
Osamu Tasaki
AHArifumi HASEGAWA
Arifumi HASEGAWA
Introduction: Different disaster activities should be performed smoothly. In relation to this, human resources for disaster activities must be secured. To achieve a stable supply of human resources, it is essential to improve the intentions of individuals responding to each type of disaster. However, the current intention of Disaster Medical Assistance Team (DMAT) members has not yet been assessed.Study Objective: To facilitate a smooth disaster response, this survey aimed to assess the intention to engage in each type of disaster activity among DMAT members.Methods: An anonymous web questionnaire survey was conducted. Japanese DMAT members in the nuclear disaster-affected area (Group A; n = 79) and the non-affected area (Group N; n = 99) were included in the analysis. The outcome was the answer to the following question: “Will you actively engage in activities during natural, human-made, and chemical (C), biological (B), radiological/nuclear (R/N), and explosive (E) (CBRNE) disasters?” Then, questionnaire responses were compared according to disaster type.Results: The intention to engage in C (50), B (47), R/N (58), and E (52) disasters was significantly lower than that in natural (82) and human-made (82) disasters (P <.001). The intention to engage in CBRNE disasters among younger participants (age ≤39 years) was significantly higher in Group A than in Group N. By contrast, the intention to engage in R/N disasters alone among older participants (age ≥40 years) was higher in Group A than in Group N. However, there was no difference between the two groups in terms of intention to engage in C, B, and E disasters. Moreover, the intention to engage in all disasters between younger and older participants in Group A did not differ. In Group N, older participants had a significantly higher intention to engage in B and R/N disasters.Conclusion: Experience with a specific type of calamity at a young age may improve intention to engage in not only disasters encountered, but also other types. In addition, the intention to engage in CBRNE disasters improved with age in the non-experienced population. To respond smoothly to specific disasters in the future, measures must be taken to improve the intention to engage in CBRNE disasters among DMAT members.

15 April 2022 in Internal Medicine
Verified
Journal Article
Open access
PDF file
KIKeita Iyama
Keita Iyama
SISatoshi Ikeda
Satoshi Ikeda
SKSeiji Koga
Seiji Koga
TYTsuyoshi Yoshimuta
Tsuyoshi Yoshimuta
HKHiroaki Kawano
Hiroaki Kawano
KMKoji Maemura
Koji Maemura
A 17-year-old boy with acute coronary syndrome was admitted to our hospital. He had xanthomas over his elbow and Achilles tendon and a high level of low-density lipoprotein cholesterol; therefore, his initial diagnosis was familial hypercholesterolemia. However, a genetic analysis revealed a compound heterozygous mutation in the ABCG5 gene with a high serum level of sitosterol, leading to the diagnosis of sitosterolemia. After lipid-lowering treatment, percutaneous coronary intervention was performed. Furthermore, a persistently high C-reactive protein level and images of large arteries led to a diagnosis of Takayasu arteritis. To our knowledge, this is the first case of sitosterolemia complicated by Takayasu arteritis.