22. 2014年4月01日 21:04:03
: trY2KTQMKc
以下はネーチャ誌の理研発表に関する最深記事：http://www.nature.com/news/stem-cell-scientist-found-guilty-of-misconduct-1.14974 Stem-cell scientist found guilty of misconduct But Japanese researcher stands by her claim to be able to produce stem cells using an acid bath or mechanical stressDavid Cyranoski、01 April 2014 RIKEN president Ryoji Noyori bows during a press conference in Tokyo, where investigators revealed the results of their investigation into Haruko Obokata's researchA committee investigating problems in papers claiming a method to apply stress to create embryonic like cells has found the lead researcher guilty of scientific misconductThe judgment is the latest twist — but not the final word — in the bizarre story of stimulus triggered activation of pluripotency (STAP), a method that researchers at the RIKEN Center for Developmental Biology (CDB) in Kobe, Japan, still say is able to turn ordinary mature mouse cells into cells that share embryonic stem cells capacity to turn into all of the body’s cellsThe technology was presented in two Nature papers1, 2 on 30 January by the CDB’s Haruko Obokata together with colleagues in Japan and the United States, but since then a slew of problems has been identified. (Nature’s News and Comment team is editorially independent of its research editorial team.)
A six-person committee — three RIKEN scientists, two university researchers and a lawyer — looked at six problems. Four were dismissed as innocent errors, but in two cases the committee found that Obokata had manipulated data in an intentionally misleading fashion. They branded it scientific misconductObokata did not appear at the press conference where the committee announced its results this morning or at an afternoon press conference where RIKEN management, led by director Ryoji Noyori, gave RIKEN's response. But in a written statement, Obokata said she planned to appeal the judgmentOne problem concerned a figure showing electrophoresis gels. One lane in a diagram had been swapped in for another. Obokata says she made the switch because the other lane was clearer and she did not think it a problem. The committee found the swap to be intentionally misleading manipulationThe committee also condemned Obokata’s use of an image from her doctoral thesis. In the doctoral thesis the image, a teratoma, was used to show the broad-ranging developmental capacity of cells she made by putting pressure on the cell membranes using a pipette. The image in the Nature paper was meant to show the same developmental capacity, but those cells were said to be made by stressing the cells with acid. Obokata said she mistakenly added the wrong image. But the committee, noting that captions on the image had been changed, judged it to be fraudulentThe committee repeatedly fended off questions about whether the technology works and thus whether STAP cells could actually exist. “That is beyond the scope of our investigation,” said committee chair Shunsuke Ishii, a molecular biologist at RIKEN in Tsukuba, JapanIn her letter, Obokata says the spliced gel lane did nothing to change the study’s results. “There was no merit in falsifying data, and I had no intention of doing so when I made the image. I only wanted to have a better image,” she writes. Use of the duplicated image was also “a simple mistake” made because the images were similar. Obokata says that she had already identified the mistakes and sent Nature a correction. Ishii says that Obokata provided teratoma slides that, she said, were from the Nature experiment. But, because of poor data management and the failure to properly label samples in the laboratory, “it’s impossible to know exactly where it came from,” he saysObokata says the committee’s judgment of misconduct is “unacceptable” and that she plans to appeal it soonThe committee also investigated the involvement of three co-authors, Yoshiki Sasai and Hitoshi Niwa, both of RIKEN CDB, and Teruhiko Wakayama, who left RIKEN last year for Yamanashi UniversitySasai, who helped Obokata write the paper, and Wakayama, in whose laboratory Obokata worked as a researcher before getting her own research unit, were cleared of involvement in the misconduct but found to carry responsibility for failure to check the dataBoth wrote letters of apology. In his, Sasai reaffirmed his belief that STAP works. “Even if the problematic data is removed, there are some results that can only be explained by STAP,” he writesNiwa’s involvement started too late in the process to warrant censorDuring the press conference, reporters expressed frustration that the investigation didn’t go further: the committee limited itself to six problems, despite the fact that other problems have been flagged. Wakayama, for example, has already initiated genetic tests which could either identify serious inconsistencies in the protocol or support the paper’s claims, but the investigation committee said it has not done any similar genetic studies on purported STAP cells left in Obokata’s laboratory. In fact, they did not have clear answers about what materials were availableAsked if there was evidence that Obokata actually did the experiments, Ishii said that “it’s difficult to tell with any kind of rigour”, since the two notebooks she provided were missing essential information, such as dates. Although he has overseen many junior researchers, “I have never experienced this kind of carelessness,” Ishii saidRIKEN will now set up a committee to determine punishments. Meanwhile, a CDB team led by Shinichi Aizawa and Niwa will spend the next year trying to test whether the technique works. Any successful outcome will be cross-checked by a third partyKenneth Lee, a developmental biologist at The Chinese University of Hong Kong, says he tried to reproduce Obokata’s results by following her protocol as closely as possible. Four attempts ended in failure. Asked if RIKEN should spend another year trying to make STAP cells, Lee says, “it makes sense — but not with her method.”
Nature doi:10.1038/nature.2014.14974 |
|
スパムメールの中から見つけ出すためにメールのタイトルには必ず「阿修羅さんへ」と記述してください。