|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Risk factors for bleeding after endoscopic mucosal resection显示文摘AIM: To clarify the risk factors for bleeding after endoscopic mucosal resection (EMR).METHODS: A total of 297 consecutive patients who underwent EMR were enrolled. Some of the patients had multiple lesions. Bleeding requiring endoscopic treatment was defined as bleeding after EMR. Odds ratios (OR) with 95% confidence intervals (CI), calculated by logistic regression with multivariate adjustments for covariates,were the measures of association.RESULTS: Of the 297 patients, 57 (19.2%) patients with bleeding after EMR were confirmed. With multivariate adjustment, the cutting method of ENR, diameter, and endoscopic pattern of the tumor were associated with the risk of bleeding after ENR. The multivariate-adjusted OR for bleeding after EMR using endoscopic aspiration mucosectomy was 3.07 (95%CI, 1.59-5.92) compared with strip biopsy. The multiple-adjusted OR for bleeding after EMR for the highest quartile (16-50 mm) of tumor diameter was 5.63 (95%CI, 1.84-17.23) compared with that for the lowest (4-7 mm). The multiple-adjusted OR for bleeding after EM R for depressed type of tumor was 4.21 (95%CI, 1.75-10.10) compared with elevated type.CONCLUSION: It is important to take tumor characteristics (tumor size and endoscopic pattern) and cutting method of EMR into consideration in predicting bleeding after ENR. | Masatsugu Shiba Kazuhide Higuchi Kaori Kadouchi Ai Montani Kazuki Yamamori Hirotoshi Okazaki Makiko Taguchi Tomoko Wada Atsushi Itani Toshio Watanabe Kazunari Tominaga Yoshihiro Fujiwara Tomoshige Hayashi Kei Tsumura Tetsuo Arakawa | 2005 | World Journal of Gastroenterology2005，11，46： | 25 |
| 2 | Quality of ulcer healing in gastrointestinal tract:Its pathophysiology and clinical relevance显示文摘In this paper,we review the concept of quality of ulcer healing(QOUH) in the gastrointestinal tract and its role in the ulcer recurrence.In the past,peptic ulcer disease(PUD) has been a chronic disease with a cycle of repeated healing/remission and recurrence.The main etiological factor of PUD is Helicobacter pylori(H.pylori),which is also the cause of ulcer recurrence.However,H.pylori-negative ulcers are present in 12%-20% of patients;they also recur and are on occasion intractable.QOUH focuses on the fact that mucosal and submucosal structures within ulcer scars are incompletely regenerated.Within the scars of healed ulcers,regenerated tissue is immature and with distorted architecture,suggesting poor QOUH.The abnormalities in mucosal regeneration can be the basis for ulcer recurrence.Our studies have shown that persistence of macrophages in the regenerated area plays a key role in ulcer recurrence.Our studies in a rat model of ulcer recurrence have indicated that proinflammatory cytokines trigger activation of macrophages,which in turn produce increased amounts of cytokines and chemokines,which attract neutrophils to the regenerated area.Neutrophils release proteolytic enzymes that destroy the tissue,resulting in ulcer recurrence.Another important factor in poor QOUH can be deficiency of endogenous prostaglandins and a deficiency and/or an imbalance of endogenous growth factors.Topically active mucosal protective and antiulcer drugs promote high QOUH and reduce inflammatory cell infiltration in the ulcer scar.In addition to PUD,the concept of QOUH is likely applicable to inflammatory bowel diseases including Crohn's disease and ulcerative colitis. | Tetsuo Arakawa Toshio Watanabe Tetsuya Tanigawa Kazunari Tominaga Yasuhiro Fujiwara Kenichi Morimoto | 2012 | World Journal of Gastroenterology2012，18，35： | 16 |
| 3 | Diversion colitis and pouchitis: A mini-review显示文摘Diversion colitis is characterized by inflammation of the mucosa in the defunctioned segment of the colon after colostomy or ileostomy. Similar to diversion colitis, diversion pouchitis is an inflammatory disorder occurring in the ileal pouch, resulting from the exclusion of the fecal stream and a subsequent lack of nutrients from luminal bacteria. Although the vast majority of patients with surgically-diverted gastrointestinal tracts remain asymptomatic, it has been reported that diversion colitis and pouchitis might occur in almost all patients with diversion. Surgical closure of the stoma, with reestablishment of gut continuity, is the only curative intervention available for patients with diversion disease. Pharmacologic treatments using short-chain fatty acids, mesalamine, or corticosteroids are reportedly effective for those who are not candidates for surgical reestablishment; however, there are no established assessment criteria for determining the severity of diversion colitis, and no management strategies to date. Therefore, in this mini-review, we summarize and review various recently-reported treatments for diversion disease. We are hopeful that the information summarized here will assist physicians who treat patients with diversion colitis and pouchitis, leading to better case management. | Kentaro Tominaga Kenya Kamimura Kazuya Takahashi Junji Yokoyama Satoshi Yamagiwa Shuji Terai | 2018 | World Journal of Gastroenterology2018，24，16： | 10 |
| 4 | tRNA cleavage: a new insight显示文摘Over the past decades,tRNA was found to be a rich hub of RNA modifications such as 1-methyladenosine and 5-methycytosine modifications and others,holding more than half of all modifications occurring in RNA molecules.Moreover,tRNA was discovered to be a source of various small noncoding RNA species,such as the stress induced angiogenin cleaved tRNA halves(tiRNA)or the miRNA like tRNA derived fragments.tRNA cleavage under stress was fist discovered in bacteria and later was found to be conserved across different species,including mammals.Under cellular stress conditions,tRNA undergoes conformational changes and angiogenin cleaves it into 3′and 5′halves.5′tiRNA halves were shown to repress protein translations.tRNA cleavage is thought of to be a cytoprotective mechanism by which cells evade apoptosis,however some data hints to the opposite;that tiRNA are cytotoxic or at least related to apoptosis initiation.tRNA cleavage also was shown to be affected by tRNA modifications via different enzymes in the cytosol and mitochondria.In this review,we will highlight the biology of tRNA cleavage,show the evidence of it being cytoprotective or a marker of cell death and shed a light on its role in disease models and human diseases as well as possible future directions in this field of RNA research. | Sherif Rashad Kuniyasu Niizuma Teiji Tominaga | 2020 | Neural Regeneration Research2020，15，1： | 5 |
| 5 | Transient receptor potential vanilloid 4-dependent calcium influx and ATP release in mouse and rat gastric epithelia显示文摘AIM: To explore the expression of transient receptor potential vanilloid 4(TRPV4) and its physiological meaning in mouse and rat gastric epithelia. METHODS: RT-PCR and immunochemistry were used to detect TRPV4 m RNA and protein expression in mouse stomach and a rat normal gastric epithelial cell line(RGE1-01), while Ca2+-imaging and electrophysiology were used to evaluate TRPV4 channel activity. ATP release was measured by a luciferin-luciferase assay. Gastric emptying was also compared between WT and TRPV4 knockout mice. RESULTS: TRPV4 m RNA and protein were detected in mouse tissues and RGE1-01 cells. A TRPV4-specific agonist(GSK1016790A) increased intracellular Ca2+ concentrations and/or evoked TRPV4-like current activities in WT mouse gastric epithelial cells andRGE1-01 cells, but not TRPV4 KO cells. GSK1016790 A or mechanical stimuli induced ATP release from RGE1-01 cells while TRPV4 knockout mice displayed delayed gastric emptying in vivo. CONCLUSION: TRPV4 is expressed in mouse and rat gastric epithelium and contributes to ATP release and gastric emptying. | Hiroshi Mihara Nobuhiro Suzuki Ammar Abdullkader Boudaka Jibran Sualeh Muhammad Makoto Tominaga Yoshiaki Tabuchi Toshiro Sugiyama | 2016 | World Journal of Gastroenterology2016，22，24： | 5 |
| 6 | Efficacy of the revised Vienna Classification for diagnosing colorectal epithelial neoplasias显示文摘AIM:To prospectively investigate the effi cacy of the revised Vienna Classifi cation for diagnosing colorectal epithelial neoplastic lesions in cold biopsy specimens.METHODS:Patients were selected for inclusion if they had colorectal epithelial lesions that were not considered suitable for direct endoscopic resection.These included colorectal polyps ≥ 10 mm and lesions suspected of being carcinomas capable of invading the colorectal submucosa or beyond,including strictures,based on the cold biopsies obtained from each lesion prior to resection.We investigated the relationship between diagnoses based on cold biopsy samples using the revised Vienna Classification and resected specimens of the same lesions,and the therapeutic implications of diagnoses made using the revised Vienna Classification.The same cold biopsy specimens were also examined using the Japanese Group Classifi cation guidelines,and compared with the resected specimens of the same lesions for reference.RESULTS:A total of 179 lesions were identified.The sensitivity,specificity,positive and negative predictive values of the revised Vienna Classification for distinguishing between intramucosal lesions and submucosal invasive carcinomas in cold biopsy specimens was 22.2%,100%,100%,and 71.4%,respectively,and for distinguishing between intramucosal lesions and those invading the submucosa or beyond was 59.7%,100%,100%,and 37.6%,respectively.The sensitivity,specificity,positive and negative predictive values of the Japanese Group Classification for distinguishing between intramucosal lesions and submucosal invasive carcinomas in cold biopsy specimens was 83.3%,91.4%,83.3%,and 91.4%,respectively,and for distinguishing between intramucosal lesions and those invading the submucosa or beyond was 95.1%,91.4%,97.9%,and 82.1%,respectively.A total of 137 of 144 carcinomas that had invaded the submucosa or beyond and three high-grade intraepithelial neoplasias were diagnosed as 'carcinoma' using the Japanese Group Classif ication system.CONCLUSION:The revised Vienna Classifi cation for cold biopsy specimens has high positive predictive value in the diagnosis of colorectal carcinoma invasive to the submucosa or beyond. | Kenji Tominaga Sumio Fujinuma Takuro Endo Yoshihisa Saida Kei Takahashi Iruru Maetani | 2009 | World Journal of Gastroenterology2009，15，19： | 5 |
| 7 | Prevalence of fatty liver in Japanese children and relationship to obesity显示文摘 | Kunihiko Tominaga MD Dr Ph John H. Kurata PhD Dr. Yang K. Chen MD Edward Fujimoto DHSc MPH Shouhei Miyagawa Ichiro Abe MSA Yoshimasa Kusano BS | | Digestive Diseases and Sciences0，，： | 5 |
| 8 | Dietary Factors and the Risk of Gastric Cancer Among Japanese Women显示文摘 | Lucy Sayuri Ito Manami Inoue Kazuo Tajima Yoshitaka Yamamura Yasuhiro Kodera Kaoru Hirose Toshiro Takezaki Nobuyuki Hamajima Tetsuo Kuroishi Suketami Tominaga | 2002 | Annals of Epidemiology2002，，1： | 4 |
| 9 | 精力的文学评论为执行 laparoscopic colorectal 外科采购原料显示文摘 Laparoscopic surgery for colorectal disease has become widespread as a minimally invasive treatment.This is important because the increasing availability of new devices allows us to perform procedures with a reduced length of surgery and decreased blood loss.We herein report the results of a literature review of energy sources for laparoscopic colorectal surgery,focused especially on 6 studies comparing ultrasonic coagulating shears(UCS) and other instruments.We also describe our laparoscopic dissection techniques using UCS for colorectal cancer.The short-term outcomes of surgeries using UCS and Ligasure for laparoscopiccolorectal surgery were superior to conventional electrosurgery.Some authors have reported that the length of surgery or blood loss when Ligasure was used for laparoscopic colorectal surgery is less than when UCS was used.On the other hand,a recent study demonstrated that there were no significant differences between the short-term outcomes of UCS and Ligasure for laparoscopic colorectal surgery.It is therefore suggested that the choice of technique used should be made according to the surgeon’s preference.We also describe our laparoscopic dissection techniques using UCS(Harmonic ACE) for colorectal cancer with regard to the retroperitoneum dissection,dissection technique,dissection technique around the feeding artery,and various other dissection techniques.We therefore review the outcomes of using various energy sources for laparoscopic colorectal surgery and describe our laparoscopic dissection techniques with UCS(Harmonic ACE) for colorectal cancer. | Tsukasa Hotta Katsunari Takifuji Shozo Yokoyama Kenji Matsuda Takashi Higashiguchi Toshiji Tominaga Yoshimasa Oku Takashi Watanabe Toru Nasu Tadamichi Hashimoto Koichi Tamura Junji Ieda Naoyuki Yamamoto Hiromitsu Iwamoto Hiroki Yamaue | 2012 | World Journal of Gastrointestinal Surgery2012，4，1： | 4 |
| 10 | Soluble ST2 protein inhibits LPS stimulation on monocyte-derived dendritic cells显示文摘ST2 蛋白质是 ST2L 蛋白质的可溶的拼接变体,它是为 interleukin-33 (IL-33 ) 的受体。以前,我们报导可溶的 ST2 在 monocytic 房间压制了 lipopolysaccharide (LPS ) 和 cytokine 生产的信号 transduction。到调查这禁止的效果是否发生在树枝状的房间,它是在天生、适应的免疫的关键播放器,人的导出单核白血球的树枝状的房间在 LPS 刺激前与可溶的 ST2 蛋白质被预先对待。尽管可溶的 ST2 没稀释树枝状的房间的导致 LPS 的成熟,有可溶的 ST2 的预告的处理压制了 cytokine 生产并且禁止了 LPS 发信号。而且,天真的 T 房间的增长被可溶的 ST2 显著地禁止预告的处理。IL-33 在不成熟的导出单核白血球的树枝状的房间的 cytokine 生产上有小效果。而且,可溶的 ST2 蛋白质被使内在化进树枝状的房间,建议那可溶的 ST2 蛋白质由除 IL-33 的隐遁以外的不在经典中的机制行动。 | Akihisa Nagata Naoki Takezako Hiroyuki Tamemoto Hiromi Ohto-Ozaki SatoshiOhta Shin-ichi Tominaga Ken Yanagisawa | 2012 | Cellular & Molecular Immunology2012，9，5： | 4 |
| 11 | Gas-forming liver abscess associated with rapid hemolysis in a diabetic patient显示文摘We experienced a case of liver abscess due to Clostridium perfringens(CP) complicated with massive hemolysis and rapid death in an adequately controlled type2 diabetic patient. The patient died 6 h after his first visit to the hospital. CP was later detected in a blood culture. We searched for case reports of CP septicemia and found 124 cases. Fifty patients survived, and 74died. Of the 30 patients with liver abscess, only 3 cases survived following treatment with emergency surgica drainage. For the early detection of CP infection, detection of Gram-positive rods in the blood or drainage fluid is important. Spherocytes and ghost cells indicate intravascular hemolysis. The prognosis is very poor once massive hemolysis occurs. The major causative organisms of gas-forming liver abscess in diabetic patients are Klebsiella pneumoniae(K. pneumoniae) and Escherichia coli(E. coli). Although CP is relatively rare,the survival rate is very poor compared with those of K. pneumoniae and E. coli. Therefore, for every case that presents with a gas-forming liver abscess, the possibility of CP should be considered, and immediate aspiration of the abscess and Gram staining are important. | Miwa Kurasawa Takashi Nishikido Junko Koike Shin-ichi Tominaga Hiroyuki Tamemoto | 2014 | World Journal of Diabetes2014，5，2： | 4 |
| 12 | Can magnifying endoscopy with narrow band imaging be useful for low grade adenomas in preoperative biopsy specimens?显示文摘 | Kazuhiro Miwa Hisashi Doyama Renma Ito Hiroyoshi Nakanishi Katsura Hirano Satoko Inagaki Kei Tominaga Naohiro Yoshida Kenichi Takemura Shinya Yamada Yoshibumi Kaneko Kazuyoshi Katayanagi Hiroshi Kurumaya Toshihide Okada Masakazu Yamagishi | 2012 | Gastric Cancer2012，，2： | 3 |
| 13 | Gastroduodenal ulcer bleeding in elderly patients on low dose aspirin therapy显示文摘AIM To determine the clinical characteristics of elderly patients of hemorrhagic gastroduodenal ulcer on low-dose aspirin(LDA)therapy.METHODS A total of 1105 patients with hemorrhagic gastroduodenal ulcer treated in our hospital between January 2000 and March 2016 were grouped by age and drugs used,and these groups were compared in several factors.These groups were compared in terms of length of hospital stay,presence/absence of hemoglobin(Hb)decrease,presence/absence of blood transfusion,Forrest Ⅰ,percentage of Helicobacter pylori infection,presence/absence of underlying disease,and percentage of severe cases.RESULTS The percentage of blood transfusion(62.6%vs 47.7%,P<0.001),Hb decrease(53.8% vs 40.8%,P<0.001),and the length of hospital stay(23.5 d vs 16.7 d,P<0.001)were significantly greater in those on drug therapy.The percentage of blood transfusion(65.3%vs 47.8%,P<0.001),Hb decrease(54.2%vs 42.1%,P<0.001),and length of hospital stay(23.3 d vs 17.5 d,P<0.001)were significantly greater in the elderly.In comparison with the LDA monotherapy group,the percentage of severe cases was significantly higher in the LDA combination therapy group when elderly patients were concerned(16.1%vs34.0%,P=0.030).Meanwhile,among those on LDA monotherapy,there was no significant difference between elderly and non-elderly(16.1%vs 16.0%,P=0.985).CONCLUSION A combination of LDA with antithrombotic drugs or nonsteroidal anti-inflammatory drugs(NSAIDs)contributes to aggravation.And advanced age is not an aggravating factor when LDA monotherapy is used. | Koh Fukushi Keiichi Tominaga Kazunori Nagashima Akira Kanamori Naoya Izawa Mimari Kanazawa Takako Sasai Hideyuki Hiraishi | 2018 | World Journal of Gastroenterology2018，24，34： | 3 |
| 14 | Endoscopic tissue shielding with polyglycolic acid sheets, fibrin glue and clips to prevent delayed perforation after duodenal endoscopic resection显示文摘 | Hisashi Doyama Kei Tominaga Naohiro Yoshida Kenichi Takemura Shinya Yamada | 2014 | Digestive Endoscopy2014，，： | 3 |
| 15 | Clinical importance of colonoscopy in patients with gastric neoplasm undergoing endoscopic submucosal dissection显示文摘AIM To evaluate the usefulness of total colonoscopy(TCS) for patients undergoing gastric endoscopic submucosal dissection(ESD) and to assess risk factors for colorectal neoplasms.METHODS Of the 263 patients who underwent ESD at our department between May 2010 and December 2013, 172 patients undergoing TCS during a one-year period before and after ESD were targeted. After excluding patients with a history of surgery or endoscopic therapy for colorectal neoplasms, 158 patients were analyzed. Of the 868 asymptomatic patients who underwent TCS during the same period because of positive fecal immunochemical test(FIT) results, 158 patients with no history of either surgery or endoscopic therapy for colorectal neoplasms who were matched for age and sex served as the control group for comparison.RESULTS TCS revealed adenoma less than 10 mm in 53 patients(33.6%), advanced adenoma in 17(10.8%), early colorectal cancer in 5(3.2%), and advanced colorectalcancer in 4(2.5%). When the presence or absence of adenoma less than 10 mm, advanced adenoma, and colorectal cancer and the number of adenomas were compared between patients undergoing ESD and FITpositive patients, there were no statistically significant differences in any of the parameters assessed. The patients undergoing ESD appeared to have the same risk of colorectal neoplasms as the FIT-positive patients. Colorectal neoplasms were clearly more common in men than in women(P = 0.031). Advanced adenoma and cancer were significantly more frequent in patients with at least two of the following conditions: hypertension, dyslipidemia, and diabetes mellitus(P = 0.019).CONCLUSION In patients undergoing gastric ESD, TCS appears to be important for detecting synchronous double neoplasms. Advanced adenoma and cancer were more common in patients with at least two of the following conditions: hypertension, dyslipidemia, and diabetes mellitus. Caution is therefore especially warranted in patients with these risk factors. | Chieko Tsuchida Naoto Yoshitake Hitoshi Kino Yoshihito Kaneko Masakazu Nakano Kohei Tsuchida Keiichi Tominaga Takako Sasai Hironori Masuyama Hidetsugu Yamagishi Yasuo Imai Hideyuki Hiraishi | 2017 | World Journal of Gastroenterology2017，23，23： | 3 |
| 16 | Effectiveness of clip-and-snare method using pre-looping technique for gastric endoscopic submucosal dissection显示文摘AIM:To evaluate efficacy and safety of clip-and-snare method using pre-looping technique(CSM-PLT)for gastric endoscopic submucosal dissection(ESD).METHODS:In the CSM-PLT method,a clip attached to the lesion side was strangulated with a snare,followed by application of an appropriate tension to the lesion independent of an endoscope.Twenty consecutive lesions were resected by ESD using CSM-PLT(CSM-PLT group)and compared with a control group,including20 lesions that were resected by conventional ESD.The control group was matched based on the size and location of the lesion,presence of pathologic fibrosis,and experience of endoscopists.Total procedure time of ESD,proportion of en bloc resection,and complications were analyzed.RESULTS:The total procedure time for the CSM-PLT group was significantly shorter than that for the control group(38.5 min vs 59.5 min,P=0.023);all lesions were resected en bloc by ESD.There was no significant difference in complications between the two groups.Moreover,there was no complication in the CSM-PLT group.In one large lesion(size:74 mm)that underwentextensive CSM-PLT during ESD,we used an additional CSM-PLT on another edge of the lesion after achieving submucosal resection to the maximum extent possible during initial CSM-PLT.In two lesions,the snare came off the lesion together with the clip after a sudden pull;nevertheless,ESD was successful in all lesions.CONCLUSION:CSM-PLT was an effective and safe method for gastric ESD. | Naohiro Yoshida Hisashi Doyama Ryosuke Ota Yasuhito Takeda Hiroyoshi Nakanishi Kei Tominaga Shigetsugu Tsuji Kenichi Takemura | 2016 | World Journal of Gastrointestinal Endoscopy2016，8，12： | 3 |
| 17 | Diagnosis and management of fibromuscular dysplasia and segmental arterial mediolysis in gastroenterology field: A mini-review显示文摘The vascular diseases including aneurysm, occlusion, and thromboses in the mesenteric lesions could cause severe symptoms and appropriate diagnosis and treatment are essential for managing patients. With the development and improvement of imaging modalities, diagnostic frequency of these vascular diseases in abdominal lesions is increasing even with the small changes in the vasculatures. Among various vascular diseases, fibromuscular dysplasia(FMD) and segmental arterial mediolysis(SAM) are noninflammatory, nonatherosclerotic arterial diseases which need to be diagnosed urgently because these diseases could affect various organs and be lethal if the appropriate management is not provided. However, because FMD and SAM are rare, the cause, prevalence, clinical characteristics including the symptoms, findings in the imaging studies, pathological findings, management, and prognoses have not been systematically summarized. Therefore, there have been neither standard diagnostic criteria nor therapeutic methodologies established, to date. To systematically summarize the information and to compare these disease entities, we have summarized the characteristics of FMD and SAM in the gastroenterological regions by reviewing the cases reported thus far. The information summarized will be helpful for physicians treating these patients in an emergency care unit and for the differential diagnosis of other diseases showing severe abdominal pain. | Masayoshi Ko Kenya Kamimura Kohei Ogawa Kentaro Tominaga Akira Sakamaki Hiroteru Kamimura Satoshi Abe Kenichi Mizuno Shuji Terai | 2018 | World Journal of Gastroenterology2018，24，32： | 2 |
| 18 | A High-Cholesterol Diet Exacerbates Liver Fibrosis in Mice via Accumulation of Free Cholesterol in Hepatic Stellate Cells显示文摘 | Toshiaki Teratani Kengo Tomita Takahiro Suzuki Tetsuya Oshikawa Hirokazu Yokoyama Katsuyoshi Shimamura Susumu Tominaga Sadayuki Hiroi Rie Irie Yoshikiyo Okada Chie Kurihara Hirotoshi Ebinuma Hidetsugu Saito Ryota Hokari Kazuo Sugiyama Takanori Kanai Soich | 2012 | Gastroenterology2012，，1： | 2 |
| 19 | A prospective, single-blind trial comparing wireless capsule endoscopy and double-balloon enteroscopy in patients with obscure gastrointestinal bleeding显示文摘 | Natsuhiko Kameda Kazuhide Higuchi Masatsugu Shiba Hirohisa Machida Hirotoshi Okazaki Hirokazu Yamagami Tetsuya Tanigawa Kenji Watanabe Toshio Watanabe Kazunari Tominaga Yasuhiro Fujiwara Nobuhide Oshitani Tetsuo Arakawa | 2008 | Journal of Gastroenterology2008，，6： | 2 |
| 20 | Ag7(MBISA)6 Nanoclusters Conjugated with Quinacrine for FRET-Enhanced Photodynamic Activity under Visible Light Irradiation显示文摘Singlet oxygen(1 O2) plays an important role in various applications, such as in the photodynamic therapy(PDT) of cancers,photodynamic inactivation of microorganisms, photo-degradation of toxic compounds, and photo-oxidation in synthetic chemistry. Recently,water-soluble metal nanoclusters(NCs) have been utilized as photosensitizers for the generation of highly reactive 1 O2 because of their high water solubility, low toxicity, and surface functionalizability for targeted substances. In the case of metal NC-based photosensitizers, the photo-physical properties depend on the core size of the NCs and the core/ligand interfacial structures. A wide range of atomically precise gold NCs have been reported; however, reports on the synthesis of atomically precise silver NCs are limited due to the high reactivity and low photostability(i.e., easy oxidation) of Ag NCs. In addition, there have been few reports on what kinds of metal NCs can generate large amounts of 1 O2. In this study, we developed a new one-pot synthesis method of water-soluble Ag7(MBISA)6(MBISA= 2-mercapto-5-benzimidazolesulfonic acid sodium salt) NCs with highly efficient 1 O2 generation ability under the irradiation of white light emitting diodes(LEDs). The molecular formula and purity were determined by electrospray ionization mass spectrometry and gel electrophoresis. To the best of our knowledge, this is the first report on atomically precise thiolate silver clusters(Agn(SR)m) for efficient 1 O2 generation under visible light irradiation. The 1 O2 generation efficiency of Ag7(MBISA)6 NCs was higher than those of the following known water-soluble metal NCs: bovine serum albumin(BSA)-Au25 NCs,BSA-Ag8 NCs, BSA-Ag14 NCs,Ag25(dihydrolipoic acid)14 NCs,Ag35(glutathione)18 NCs,and Ag75(glutathione)40 NCs. The metal NCs examined in this study showed the following order of 1 O2 generation efficiency under white light irradiation: Ag7(MBISA)6 > BSA-Ag14 > Ag75(SG)40 > Ag35(SG)18 >BSA-Au25 >>BSA-Ags(not detected) and Ag2 s(DHLA)14(not detected). For further improving the 1 O2 generation of Ag7(MBISA)6 NCs, we developed a novel fluorescence resonance energy transfer(FRET) system by conjugating Ag7(MBISA)6 NCs with quinacrine(QC)(molar ratio of Ag NCs to QC is 1 : 0.5). We observed the FRET process,from QC to Ag7(MBISA)6 NCs,occurring in the conjugate. That is,the QC works as a donor chromophore,while the Ag NCs work as an acceptor chromophore in the FRET process. The FRET-mediated process caused a 2.3-fold increase in 1 O2 generation compared to that obtained with Ag7(MBISA)6 NCs alone. This study establishes a general and simple strategy for improving the PDT activity of metal NC-based photosensitizers. | TOMINAGA Chiaki HIKOSOU Dailo OSAKA Issey KAWASAK Hideya | 2018 | 物理化学学报2018，34，7： | 2 |
您所在的机构暂未开通此部分的功能，请联系管理员