Naoya Tada

Dr. Naoya Tada


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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典西典子 西山
典子 西山
Hideki KobaraHideki Kobara
Hideki Kobara
MAMaki Ayaki
Maki Ayaki
Shintaro FujiharaShintaro Fujihara
Shintaro Fujihara
KNKaho Nakatani
Kaho Nakatani
KHKen Haruma
Ken Haruma
White globe appearance (WGA) is defined as a microendoscopic white lesion with a globular shape underlying the gastric epithelium and is considered a marker of gastric cancer. We recently reported that endoscopically visualized white spot (WS) corresponding to WGA appeared on the nonatrophic mucosa of patients with acid-suppressing agents (A-SA) use. We evaluated patients undergoing routine esophagogastroduodenoscopy and divided the patients into an A-SA group (n = 112) and a control group (n = 158). We compared the presence of WS in both groups. We also compared WS-positive- (n = 31) and -negative (n = 43) groups within the A-SA group regarding these patients’ backgrounds and serum gastrin concentrations. Comparing the A-SA group with controls, the prevalence of WS was significantly higher (31/112 vs. 2/158; p < 0.001). The number of patients with high serum gastrin concentrations was significantly higher in the WS-positive group (18/31) vs. the WS-negative group (5/43) (p < 0.001). Within the A-SA group, the prevalence of WS was also significantly higher in patients taking potassium-competitive acid blockers vs. proton-pump inhibitors (21/31 vs. 10/31, p < 0.001). The WS-positive group had a significantly greater percentage of patients, with a high serum gastrin level (p < 0.001). WS may be associated with hypergastrinemia and potassium-competitive acid blockers.

16 October 2021 in Journal of Clinical Medicine
Verified
Journal Article
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Hideki KobaraHideki Kobara
Hideki Kobara
KUKunihisa Uchita
Kunihisa Uchita
NUNoriya Uedo
Noriya Uedo
JKJun Kunikata
Jun Kunikata
KYKenji Yorita
Kenji Yorita
KHKoki Hirano
Koki Hirano
We aimed to investigate the diagnostic ability of magnifying endoscopy with narrow band imaging (ME-NBI) for cervical intraepithelial neoplasia grade 2 or worse (CIN2+). This was a multicenter prospective study. Eligible patients had positive Pap smear results or follow-up high-grade cytology or CIN3 diagnosed in referring hospitals. Patients underwent ME-NBI by a gastrointestinal endoscopist, followed by colposcopy by a gynecologist. One lesion with the worst finding was considered the main lesion. Punch biopsies were collected from all indicated areas and one normal area. The reference standard was the highest histological grade among all biopsy specimens. The primary endpoint was the detection rate of patients with CIN2+ in the main lesion. The secondary endpoints were diagnostic ability for CIN2+ lesions and patients’ acceptability. We enrolled 88 patients. The detection rate of ME-NBI for patients with CIN2+ was 79% (95% CI: 66–88%; p = 1.000), which was comparable to that of colposcopy (79%; p = 1.000). For diagnosing CIN2+ lesions, ME-NBI showed a better sensitivity than colposcopy (87% vs. 74%, respectively; p = 0.302) but a lower specificity (50% vs. 68%, respectively; p = 0.210). Patients graded ME-NBI as having significantly less discomfort and involving less embarrassment than colposcopy. ME-NBI did not show a higher detection ability than colposcopy for patients with CIN2+, whereas it did show a better patient acceptability.

1 January 2022 in Digestive and Liver Disease
Verified
Journal Article
Closed access
NTNaoya Tada
Naoya Tada
HKHideki Kobara
Hideki Kobara
NNNoriko Nishiyama
Noriko Nishiyama
TMTsutomu Masaki
Tsutomu Masaki

14 September 2021 in Diagnostics
Verified
Journal Article
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Shintaro FujiharaShintaro Fujihara
Shintaro Fujihara
Hideki KobaraHideki Kobara
Hideki Kobara
典西典子 西山
典子 西山
NTNaoya Tada
Naoya Tada
KKKazuhiro Kozuka
Kazuhiro Kozuka
TMTsutomu Masaki
Tsutomu Masaki
Esophagogastroduodenoscopy (EGD) has a high risk of virus transmission during the current coronavirus disease 2019 era, and preventive measures are under investigation. We investigated the effectiveness of a newly developed patient-covering negative-pressure box system (Endo barrier®) (EB) for EGD. Eighty consecutive unsedated patients who underwent screening EGD with EB use were prospectively enrolled. To examine the aerosol ratio before, during, and after EGD, 0.3- and 0.5-μm aerosols were measured every 60 s using an optical counter. Moreover, the degree of contamination of the examiners’ goggles and vinyl gowns was assessed before and after EGD using a rapid adenosine triphosphate (ATP) test for simulated droplets. Data were available in 73 patients and showed that 0.3- and 0.5-μm particles did not increase in 95.8% (70/73) and 94.5% (69/73) of patients during EGD under EB. There were no significant differences in the total 0.3- or 0.5-μm particle counts before versus after EGD. The difference in the ATP levels before and after EGD was −0.6 ± 16.6 relative light units (RLU) on goggles and 1.59 ± 19.9 RLU on gowns (both within the cutoff value). EB use during EGD may provide a certain preventive effect against aerosols and droplets, decreasing examiners’ exposure to viruses.

28 December 2020 in Digestive Endoscopy
Verified
Journal Article
Open access
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NTNaoya Tada
Naoya Tada
Hideki KobaraHideki Kobara
Hideki Kobara
TMTsutomu Masaki
Tsutomu Masaki
Watch a video of this article.

12 September 2020 in Diagnostics
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Journal Article
Open access
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Hideki KobaraHideki Kobara
Hideki Kobara
NKNobuya Kobayashi
Nobuya Kobayashi
典西典子 西山
典子 西山
NTNaoya Tada
Naoya Tada
Shintaro FujiharaShintaro Fujihara
Shintaro Fujihara
TMTsutomu Masaki
Tsutomu Masaki
Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) has emerged as a standard and convenient method for the sampling of subepithelial lesions (SELs). Immunohistological analysis is required to definitively distinguish mesenchymal tumors; however, EUS-FNA provides insufficient material to achieve this, especially for small SELs < 2 cm. We therefore previously reported a novel submucosal tunneling biopsy (STB) technique that utilizes endoscopic submucosal dissection (ESD) for sampling SELs. However, unresolved advanced technical issues have hindered its widespread application. Currently, a counter-traction technique is used to facilitate ESD. We here describe a technically simplified STB technique using clip-with-line traction for gastric SELs.