Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
YUKO INAI Last modified date:2022.05.19

Research Associate / Division of general dentistry / Comprehensive Dentistry / Kyushu University Hospital

1. Yoshiaki Nomura ,Yuko Inai , Yudai Shimpo, Ayako Okada, Yuko Yamamoto , Kaoru Sogabe , Naohisa Wada, and Nobuhiro Hanada , Incidence of Postoperative Pneumonia and Oral Microbiome for Patients with Cancer Operation, Applied Sciences, , 2022.03, Postoperative pneumonia is a serious problem for patients and medical staff. In Japan, many hospitals introduced perioperative oral care management for the efficient use of medical resources. However, a high percentage of postoperative pneumonia still developed. Therefore, there is a need to identify the specific respiratory pathogens to predict the incidence of pneumonia The purpose of this study was to find out the candidate of bacterial species for the postoperative pneumonia. This study applied case-control study design for the patients who had a cancer operation with or without postoperative pneumonia. A total of 10 patients undergoing a cancer operation under general anesthesia participated in this study. The day before a cancer operation, preoperative oral care management was applied. Using the next generation sequence, oral microbiome of these patients was analyzed at the time of their first visit, the day before and after a cancer operation. Porphyromonas gingivalis and Fusobacterium nucleatum group can be a high risk at first visit. Atopobium parvulum and Enterococcus faecalis before a cancer operation can be a high risk. Poor oral hygiene increased the risk of incidence of postoperative pneumonia. Increased periodontal pathogens can be a high risk of the incidence of postoperative pneumonia. In addition, increased intestinal bacteria after oral care management can also be a high risk for the incidence of postoperative pneumonia..
2. Kai N, Tsukamoto Y, Urabe K, Tani A,Inai Y, Okadome A, Kashiwazaki H, Mizutani S , Wada N, Factors That Influence the Judgment of Oral Management Necessity in Preoperative Oral Screening, Int J Environ Res. and public.Health 2021, 10.3390/ijerph182212236, 2021.10, Oral management during the perioperative period is important to prevent the development of postoperative complications. However, there are no unified systems to examine the oral status of patients and very few studies have focused on preoperative oral screening. In this study, we examined the oral status of patients who underwent oral screening at a University Hospital. A total of 1173 patients who underwent oral screening for perioperative management from April 2020 to July 2021 were enrolled. The subjects’ medical data were retrospectively extracted from the dental records, and finally, the data of 1081 patients aged ≥20 years were analyzed. Oral screening based on seven categories was performed by dentists or dental hygienists. Our cumulative results determined whether patients required oral management during the perioperative period. “Poor oral hygiene” was the most frequent category (24%) of all oral categories examined. Logistic analysis revealed that tooth mobility had the highest odds ratio (21.476; 95% confidence interval: 11.462–40.239; p < 0.001) for oral management necessity during the perioperative period. Our study suggests that poor oral hygiene is most frequently observed in preoperative oral screening. Moreover, tooth mobility in preoperative oral screening may influence the judgment of oral management necessity during the perioperative period..
3. Naoko Nakahodo , Yoshiaki Nomura , Takumi Oshiro , Ryoko Otsuka , Erika Kakuta ,Ayako Okada , Yuko Inai , Noriko Takei and Nobuhiro Hanada, Effect of Mucosal Brushing on the Serum Levels of C-Reactive Protein for Patients Hospitalized with
Acute Symptoms, Medicina, 10.3390/medicina56100549, 2020.10, This study was based in a hospital setting. Patients with acute symptoms face a life-threatening crisis and often have systemic complications during the convalescence stage. During the acute stage, oral function does not work and oral hygiene status deteriorates. A gauze or sponge brush is generally used to wipe the oral cavity; however, this process does not clean the oral cavity enough. Effective oral care requires better methods. Patients participating in this study were all hospitalized by ambulance and with acute symptoms. During the convalescence stage, patients were assigned application of mucosal brushing or wiping by gauze or sponge brush by order of hospitalization. The effects were evaluated by the number of bacteria on the tongue surface, serum C-reactive protein (CRP) and body temperature. Changes in bacterial count, body temperature, and CRP were effectively reduced in the mucosal brushing group compared to the wiping by gauze or sponge brush group. Based on mixed effect modeling, the coefficient of mucosal brushing for CRP was −2.296 and for body temperature was −0.067 and statistically significant. This simple method can effectively prevent systemic complication of inpatients with deteriorated oral conditions. This method may also be effective for the elderly in nursing homes or perioperative oral-care management..
4. Shoji Miyazono, Takahito Otani, Kayoko Ogata, Norio Kitagawa, Hiroshi Iida, Yuko Inai, Takashi Matsuura & Tetsuichiro Inai , The reduced susceptibility of mouse keratinocytes to retinoic acid may be involved in the keratinization of oral and esophageal mucosal epithelium, Histochemistry and Cell Biology, 2020.02, 123
Histochemistry and Cell Biology
ISSN 0948-6143
Histochem Cell Biol
DOI 10.1007/s00418-020-01845-1
The reduced susceptibility of mouse
keratinocytes to retinoic acid may be
involved in the keratinization of oral and
esophageal mucosal epithelium
Shoji Miyazono, Takahito Otani,
Kayoko Ogata, Norio Kitagawa, Hiroshi
Iida, Yuko Inai, Takashi Matsuura &
Tetsuichiro Inai
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Vol.:(0112 33456789)
Histochemistry and Cell Biology
The reduced susceptibility of mouse keratinocytes to retinoic acid
may be involved in the keratinization of oral and esophageal mucosal
Shoji Miyazono1 · Takahito Otani2 · Kayoko Ogata2 · Norio Kitagawa2 · Hiroshi Iida3 · Yuko Inai4 · Takashi Matsuura1 ·
Tetsuichiro Inai2
Accepted: 14 January 2020
© Springer-Verlag GmbH Germany, part of Springer Nature 2020
Keratinocytes take up serum-derived retinol (vitamin A) and metabolize it to all-trans-retinoic acid (atRA), which binds
to the nuclear retinoic acid receptor (RAR). We previously reported that serum-affected keratinocyte differentiation and
function; namely, it inhibited keratinization, decreased loricrin (LOR) and claudin (CLDN) 1 expression, increased keratin
(K) 4 and CLDN4 levels, and reduced paracellular permeability in three-dimensional (3D) cultures of mouse keratinocytes
(COCA). Contrarily, RAR inhibition reversed these changes. Here, we aimed to examine whether atRA exerted the same
effects as serum, and whether it was involved in the differential oral mucosa keratinization among animal species. Porcine
oral mucosal keratinocytes, which form non-keratinized epithelium in vivo, established keratinized epithelium in 3D cultures.
Both mouse and porcine sera induced non-keratinized epithelium at 0.1% in COCA 3D cultures. Although atRA caused the
same changes as serum, its effective concentration differed. atRA inhibited keratinization at 0.1 nM and 1 nM in porcine or
human keratinocytes and COCA, respectively. Furthermore, atRA upregulated CLDN7 in the cytoplasm but not in cell–cell
contacts. These atRA-induced changes were reverted by RAR inhibition. The results indicate that serum-induced changes are
probably due to the effect of serum-derived atRA, and that mouse keratinocytes require higher atRA concentrations to suppress
keratinization than porcine and human keratinocytes. We propose that the lower susceptibility of mouse keratinocytes to
atRA, rather than a lower retinol concentration, is a possible reason for the keratinization of mouse oral mucosal epithelium.
Keywords Retinoic acid · Keratinocyte · Three-dimensional culture · Keratinization · Tight junction · Claudin
5. Yuko Inai, Yoshiaki Nomura, Tohru Takarada, Nobuhiro Hanada, Naohisa Wada, Risk factors for postoperative pneumonia according to examination findings before surgery under general anesthesia, clinical oral investigations, 10.1007/s00784-020-03230-7, 2020.02, Objective: This study was performed to determine the risk factors associated with postoperative complications after surgery under general anesthesia according to respiratory function test results and oral conditions.
Materials and methods: Preoperative examination data were collected for 471 patients who underwent surgery under general anesthesia at the Medical Hospital of Kyusyu University. Respiratory function tests, oral examinations, and perioperative oral management were performed in all patients. The incidence of and risk factors for postoperative complications were investigated. Classification and regression tree analyses were performed to investigate the risk factors for postoperative complications.
Results: Among the 471 patients, 11 developed postoperative pneumonia, 10 developed postoperative respiratory symptoms, and 10 developed postoperative fever. The most important risk factor for pneumonia was edentulism. Age, the Brinkman index, and head and neck surgery were also revealed as important risk factors for pneumonia. The O’Leary plaque control record (initial visit) was an important risk factor for postoperative respiratory symptoms. With respect to postoperative fever, a Hugh–Jones classification of grade >1 was the most important risk factor; edentulism and a Brinkman index of >642.5 were also found to be risk factors.
Conclusion: In addition to respiratory function tests, oral examinations may be important for the prediction of postoperative complications. Additionally, improved oral hygiene may be effective in preventing postoperative respiratory complications.
Clinical relevance: Risk factors for postoperative complications should be comprehensively evaluated using both respiratory function tests and oral findings..
6. The relationship between the number of teeth and walking speed in Japanese over 50 years old.
7. Yuko Inai, Yoshiaki Nomura, Tohru Takarada, Junichi Yamazoe, Koko Hidaka, Nobuhiro Hanada, Naohisa Wada, Risk Factors for Postoperative Complications in Patients with Esophageal Cancer Receiving Perioperative Oral
Management, Journal of dentistry and oral care, 10.15436/2379-1705.18.1940, 2018.11, Objective: The aim of this study was to determine the factors associated with postoperative complications after surgery for esophageal cancer to promote improvement of perioperative oral management protocols.
Methods: Data were collected from 42 patients who underwent surgery for esophageal cancer under general anesthesia.Oral examination and perioperative oral management were performed in all patients. The incidence of complications and their risk factors were investigated. Classification and regression tree analysis were performed to determine the factors predicting the occurrence of postoperative complications.
Results: Among 42 patients, 16 had postoperative respiratory symptoms, 5 had postoperative pneumonia, and 20 had postoperative fever. The most important risk factor for postoperative respiratory symptoms was the presence of 19.5 or more remaining teeth. Oral care initiation more than 2.5 days after surgery, operation time longer than 6.5 hours, and postoperative fasting period longer than 4.5 days were also risk factors for postoperative respiratory symptoms. A preoperative O’Leary’s plaque control record above 40% was the most important risk factor for the occurrence of postoperative pneumonia. Fasting period longer than 8.5 days and the presence of 19.5 or more remaining teeth were also risk factors for postoperative pneumonia. Oral care initiation more than 2.5 days after surgery and fasting period longer than 8.5 days were risk factors for fever.
Conclusion: Starting professional oral care immediately after surgery and establishing effective self-care may be important to prevent postoperative complications in patients with esophageal cancer..
8. Norio Kitagawa, Yuko Inai, Yoshinori Higuchi, Hiroshi Iida, Tetsuichiro Inai, Inhibition of JNK in HaCaT cells induced tight junction formation with decreased expression of cytokeratin 5, cytokeratin 17 and desmoglein 3, Histochemistry and Cell Biology, 10.1007/s00418-014-1219-9, 142, 4, 389-399, 2014.01, Epidermal keratinocytes proliferate in the basal layer, differentiate, migrate through the spinous layer, granular layer and cornified layer, and finally are peeled off from the surface of skin with layer-specific expression of differentiation markers, including cytokeratins and cell–cell junction proteins such as desmogleins. Basal cells express CK5, CK14 and Ki67. In contrast, the suprabasal cells in the spinous and granular layers express CK1 and CK10 without Ki67. Inhibition of c-Jun NH2-terminal protein kinase (JNK) in HaCaT cells, a human epidermal keratinocyte cell line, induced the formation of tight junctions, which occurs in the granular layer in vivo. These cells lost their expression of CK5 and CK17, exhibited decreased expression of desmoglein 3 and had no Ki67 labeling in the nucleus. These results suggest that inhibition of JNK causes HaCaT cells to differentiate from basal- and spinous-like cells to granular-like cells. The inhibition of JNK in HaCaT cells provides a useful in vitro model system to study the differentiation of epidermal keratinocytes..
9. Y. Nakano, Yuuko Inai, Yoshihisa Yamashita, S. Nagaoka, T. Kusuzaki‐Nagira, T. Nishihara, N. Okahashi, T. Koga, Molecular and immunological characterization of a 64‐kDa protein of Actinobacillus actinomycetemcomitans, Oral Microbiology and Immunology, 10.1111/j.1399-302X.1995.tb00136.x, 10, 3, 151-159, 1995.01, The 64‐kDa protein to which about half the sera from patients with localized juvenile periodontitis and rapidly progressive periodontitis reacted strongly was purified from Actinobacillus actinomycetemcomitans Y4. Determination of the TV‐terminal sequence of the protein revealed that it was a GroEL‐like protein. The DNA fragment containing the groEL gene of A. actinomycetemcomitans was amplified by polymerase chain reaction, and the groESL operon was cloned by using colony hybridization with the amplified fragment from A. actinomycetemcomitans chromosomal DNA. Sequence analysis revealed that structures of the operon and its products were typical in gram‐negative bacteria. Rabbit polyclonal antibodies to the 64‐kDa protein cross‐reacted with approximately 65‐kDa proteins of Haemophilus aphrophilus, Haemophilus influenzae, Haemophilus paraphrophilus, Escherichia coli and Eikenella corrodens but not with any cellular proteins of Porphyromonas gingivalis, Prevotella intermedia and Fusobacteriuni nucleatum. It is possible that antibodies reactive to the 64‐kDa protein in periodontitis patients are induced by the cross‐reactivity with the hsp60 proteins of other bacteria..
10. Tetsuichiro Inai, Yuko Inai, Kojiro Kurisu, Immunohistochemical detection of an enamel protein-related epitope in rat bone at an early stage of osteogenesis, Histochemistry, 10.1007/BF00717047, 99, 5, 355-362, 1993.05, Monoclonal antibody MI315 was produced against hamster tooth germ homogenate by in vitro immunization. It was found that MI315 reacted with enamel matrix, ameloblasts, and bone matrix at an early stage of osteogenesis. Decalcified tissues of rat femurs and mandibles were examined with MI315 using indirect immunofluorescence. In endochondral ossification of femurs, immunoreactivity was found in bone extracellular matrix (ECM) deposited on the surface of the cartilage core of primary spongiosa, but not in the cartilage core itself. In intramembranous ossification of 0-day-old rat mandibles, intense immunofluorescence was detected in bone ECM and a few young osteocytes, but not in osteoblasts. Immunoreactivity in bone ECM of 2-day-old rats decreased and almost disappeared from bone ECM of 4-day-old rats. Although in nondecalcified sections of 0-day-old rats, negligible immunofluorescence was detected in bone ECM which showed positive staining in decalcified tissues, the immunostaining appeared after decalcification using ethylenediaminetetraacetic acid (EDTA). These results indicate that a substance(s), which had a common epitope with an enamel-derived protein(s), existed in immature bone ECM of both endochondral and intramembranous ossification, and that it might be masked by bone mineral. Monoclonal antibody MI315 is a useful tool to investigate the time- and position-specific changes in osteogenesis and amelogenesis..