研究者総覧

笹原 鉄平 (ササハラ テッペイ)

  • 感染・免疫学講座(臨床感染症学部門) 准教授
Last Updated :2021/09/22

研究者情報

学位

  • 博士(医学)(自治医科大学)

ホームページURL

科研費研究者番号

  • 30448849

J-Global ID

研究キーワード

  • 性感染症   医療関連感染   病院環境汚染   芽胞形成菌   感染制御   

研究分野

  • ライフサイエンス / 感染症内科学 / 感染制御

経歴

  • 2015年01月 - 現在  自治医科大学医学部講師
  • 2010年04月  自治医科大学医学部助教
  • 2006年04月 - 2010年03月  自治医科大学附属病院臨床感染症センターフェロー
  • 2003年04月 - 2006年03月  国立国際医療センター総合診療科レジデント

学歴

  • 2006年04月 - 2010年03月   自治医科大学   医学部大学院
  • 1997年04月 - 2003年03月   札幌医科大学   医学部

所属学協会

  • 日本防菌防黴学会   日本性感染症学会   日本プライマリ・ケア連合学会   日本環境感染学会   日本臨床薬理学会   日本化学療法学会   日本感染症学会   日本内科学会   

研究活動情報

論文

  • Teppei Sasahara, Shunji Hayashi, Kouichi Hosoda, Yuji Morisawa, Yoshikazu Hirai
    BIOCONTROL SCIENCE 19 3 129 - 134 2014年09月 [査読有り][通常論文]
     
    Bacillus cereus is a spore-forming bacterium. B. cereus occasionally causes nosocomial infections, in which hand contamination with the spores plays an important role. Therefore, hand hygiene is the most important practice for controlling nosocomial B. cereus infections. This study aimed to determine the appropriate hand hygiene procedure for removing B. cereus spores. Thirty volunteers' hands were experimentally contaminated with B. cereus spores, after which they performed 6 different hand hygiene procedures. We compared the efficacy of the procedures in removing the spores from hands. The alcohol-based hand-rubbing procedures scarcely removed them. The soap washing procedures reduced the number of spores by more than 2 log(10). Extending the washing time increased the spore-removing efficacy of the washing procedures. There was no significant difference in efficacy between the use of plain soap and antiseptic soap. Handwashing with soap is appropriate for removing B. cereus spores from hands. Alcohol-based hand-rubbing is not effective.
  • 笹原 鉄平, 大西 翼, 渡辺 美智代
    日本環境感染学会誌 = Japanese journal of environmental infecions 29 6 424 - 428 日本環境感染学会 2014年 [査読有り][通常論文]
  • Masanori Ogawa, Teppei Sasahara
    JOURNAL OF OCCUPATIONAL MEDICINE AND TOXICOLOGY 7 24  2012年12月 [査読有り][通常論文]
     
    Background: Biological monitoring is used to assess toluene exposure in medical examinations. The American Conference of Industrial Hygienists, Japanese Society for Occupational Health and Deutsche Forschungsgemeinschaft have proposed various biological exposure determinants, such as toluene in blood and urine, and o-cresol in urine. Toluene in blood is a common biomarker among them. Toluene is a volatile organic solvent; therefore, sample preservation under appropriate conditions before measurement is necessary. However, little study has been done on the stability of toluene in workers' blood samples under conditions simulating those of a medical examination. Finding: We carried out a pilot study on the stability of toluene in blood from humans, according to different methods of sample preservation. Toluene in blood was analyzed by head space-gas chromatography/mass spectrometry. The sealing performance of the vial was examined by using toluene-added blood and the stability of toluene in blood according to the preservation period was examined by using blood from toluene-handling workers, which was collected with vacuum blood tubes. The sealing performance of the headspace vial used in this study was good for three days and toluene in blood in tubes from workers was stable at least within 8 hours up to blood packing at 4 degrees C. Conclusion: We could propose that the collected blood need only be transferred into headspace vials on the collection day and analyzed within a few days, if the samples are preserved at 4 degrees C. Our data size is limited; however, it may be considered basic information for biological monitoring in medical examinations.
  • Masataka Oda, Manabu Hashimoto, Masaya Takahashi, Yuka Ohmae, Soshi Seike, Ryoko Kato, Aoi Fujita, Hideaki Tsuge, Masahiro Nagahama, Sadayuki Ochi, Teppei Sasahara, Shunji Hayashi, Yoshikazu Hirai, Jun Sakurai
    PLOS ONE 7 6 e38054  2012年06月 [査読有り][通常論文]
     
    Bacillus cereus (B. cereus) is a pathogen in opportunistic infections. Here we show that Bacillus cereus sphingomyelinase (Bc-SMase) is a virulence factor for septicemia. Clinical isolates produced large amounts of Bc-SMase, grew in vivo, and caused death among mice, but ATCC strains isolated from soil did not. A transformant of the ATCC strain carrying a recombinant plasmid containing the Bc-SMase gene grew in vivo, but that with the gene for E53A, which has little enzymatic activity, did not. Administration of an anti-Bc-SMase antibody and immunization against Bc-SMase prevented death caused by the clinical isolates, showing that Bc-SMase plays an important role in the diseases caused by B. cereus. Treatment of mouse macrophages with Bc-SMase resulted in a reduction in the generation of H2O2 and phagocytosis of macrophages induced by peptidoglycan (PGN), but no effect on the release of TNF-alpha and little release of LDH under our experimental conditions. Confocal laser microscopy showed that the treatment of mouse macrophages with Bc-SMase resulted in the formation of ceramide-rich domains. A photobleaching analysis suggested that the cells treated with Bc-SMase exhibited a reduction in membrane fluidity. The results suggest that Bc-SMase is essential for the hydrolysis of SM in membranes, leading to a reduction in phagocytosis.
  • T. Sasahara, S. Hayashi, Y. Morisawa, T. Sakihama, A. Yoshimura, Y. Hirai
    EUROPEAN JOURNAL OF CLINICAL MICROBIOLOGY & INFECTIOUS DISEASES 30 2 219 - 226 2011年02月 [査読有り][通常論文]
     
    We describe an outbreak of Bacillus cereus bacteremia that occurred at Jichi Medical University Hospital in 2006. This study aimed to identify the source of this outbreak and to implement appropriate control measures. We reviewed the charts of patients with blood cultures positive for B. cereus, and investigated B. cereus contamination within the hospital environment. Genetic relationships among B. cereus isolates were analyzed. Eleven patients developed B. cereus bacteremia between January and August 2006. The hospital linens and the washing machine were highly contaminated with B. cereus, which was also isolated from the intravenous fluid. All of the contaminated linens were autoclaved, the washing machine was cleaned with a detergent, and hand hygiene was promoted among the hospital staff. The number of patients per month that developed new B. cereus bacteremia rapidly decreased after implementing these measures. The source of this outbreak was B. cereus contamination of hospital linens, and B. cereus was transmitted from the linens to patients via catheter infection. Our findings demonstrated that bacterial contamination of hospital linens can cause nosocomial bacteremia. Thus, blood cultures that are positive for B. cereus should not be regarded as false positives in the clinical setting.
  • 林俊治, 笹原鉄平, 吉村章, 森澤雄司, 高岡恵美子, 平井義一
    臨床検査 53 4 501 - 506 2009年04月 [査読無し][通常論文]
  • 笹原 鉄平, 林 俊治, 森澤 雄司, 平井 義一
    日本環境感染学会誌 24 5 312 - 318 一般社団法人 日本環境感染学会 2009年 [査読有り][通常論文]
     
    病院で使用するタオルには,加熱処理が義務づけられている.しかし,熱に耐性であるBacillus cereusの芽胞が病院タオルを汚染することがある.さらに,病院タオルのB. cereus汚染は医療関連感染の原因となりうる.したがって,病院タオルのB. cereus汚染を定期的に評価する必要がある.しかし,その評価のための標準方法は確立されていない.今回の研究において,我々は4つの測定方法(スタンプ法・スワブ法・単純抽出法・ビーズ抽出法)を用いて,病院タオルのB. cereus汚染の評価を行なった.スタンプ法ではタオル汚染を定量評価することが不可能であった.また,スワブ法では病院タオルから少数のB. cereusしか検出できなかった.一方,抽出法では病院タオルから多数のB. cereusを検出することができた.特に,ビーズ抽出法では単純抽出法の2倍の菌数を検出することができた.以上の結果より,ビーズ抽出法は病院タオルのB. cereus汚染の評価に最も適した測定方法と考えられる.さらに本研究の結果から,タオル中のB. cereusの分布密度が不均一であることが判明した.したがって,タオルのB. cereus汚染を評価する場合,1枚のタオルから複数のサンプル断片を採取して調べる必要がある.
  • 笹原鉄平, 中原康雄, 上坂義和, 國本雅也, 田山二朗
    神経治療学 23 2 151 - 155 2006年03月 [査読有り][通常論文]

書籍

  • 感度と特異度からひもとく感染症診療のDecision Making
    笹原鉄平 (担当:分担執筆範囲:梅毒血清検査 クラミジア・トラコマチス抗原(遺伝子検査を除く))
    文光堂 2012年
  • 感染症事典
    笹原鉄平 (担当:分担執筆範囲:セレウス菌)
    オーム社 2012年
  • 感染症診療ガイドライン総まとめ
    笹原鉄平 (担当:分担執筆範囲:性感染症)
    総合医学社 2010年
  • 市中感染症診療の考え方と進め方IDATEN感染症セミナー
    笹原鉄平 (担当:分担執筆範囲:細菌性髄膜炎のマネジメント)
    医学書院 2009年
  • 抗菌薬について内心疑問に思っていることQ&A
    笹原鉄平 (担当:分担執筆範囲:抗菌薬治療の効果判定はどのようにすればよいですか? 抗菌薬治療中, その抗菌薬を無効と判断した場合, どうしたらよいですか?)
    羊土社 2009年
  • 臨床に直結する感染症診療のエビデンス
    笹原鉄平 (担当:分担執筆範囲:クリプトコッカス髄膜炎 (Cryptococcal meningo- encephalitis) の治療において血清および髄液中クリプトコッカス抗原(Cryptococcal polysaccharide antigen)のtiterモニタリングは治療効果の指標となりうるか?)
    文光堂 2008年

講演・口頭発表等

MISC

受賞

  • 2012年11月 East Asian Conference on Infection control and Prevention Silver award
     Bacterial Growth in Intravenous Fluid Products 
    受賞者: 笹原鉄平
  • 2006年10月 Hospital Infection Society Poster award
     Staphylococcal scalded skin syndrome outbreak due to methicillin-resistant Staphylococcus aureus in the neonatal care unit 
    受賞者: 笹原鉄平

共同研究・競争的資金等の研究課題

担当経験のある科目

  • テュートリアル・診断学自治医科大学
  • 臨床感染症学自治医科大学
  • 細菌学自治医科大学


Copyright © MEDIA FUSION Co.,Ltd. All rights reserved.