257 research outputs found
木質基質に依存した秋田スギ天然林の維持・更新機構
学位の種別: 論文博士審査委員会委員 : (主査)東京大学教授 丹下 健, 東京大学教授 井出 雄二, 東京大学教授 福田 健二, 東京大学准教授 梶本 卓也, 東京大学講師 増守 眞也University of Tokyo(東京大学
Rearrangement of Mouse Immunoglobulin Kappa Deleting Element Recombining Sequence Promotes Immune Tolerance and Lambda B Cell Production
SummaryThe recombining sequence (RS) of mouse and its human equivalent, the immunoglobulin (Ig) kappa deleting element (IGKDE), are sequences found at the 3′ end of the Ig kappa locus (Igk) that rearrange to inactivate Igk in developing B cells. RS recombination correlates with Ig lambda (Igλ) light (L) chain expression and likely plays a role in receptor editing by eliminating Igk genes encoding autoantibodies. A mouse strain was generated in which the recombination signal of RS was removed, blocking RS-mediated Igk inactivation. In RS mutant mice, receptor editing and self-tolerance were impaired, in some cases leading to autoantibody formation. Surprisingly, mutant mice also made fewer B cells expressing lambda chain, whereas λ versus κ isotype exclusion was only modestly affected. These results provide insight into the mechanism of L chain isotype exclusion and indicate that RS has a physiological role in promoting the formation of λ L chain-expressing B cells
A Case of Primary Signet-Ring Cell/Histiocytoid Carcinoma of the Eyelid: Immunohistochemical Comparison With the Normal Sweat Gland and Review of the Literature
Primary signet-ring cell/histiocytoid carcinomas of the eyelid are extremely rare tumors considered to originate from sweat glands. Here, we report the case of a 72-year-old man diagnosed with primary signet-ring cell/histiocytoid carcinoma of the eyelid and present immunohistochemical analyses of the eyelid apocrine gland (Moll gland) and apocrine and eccrine sweat glands of perineum and axilla. Widespread infiltration of tumor cells with signet-ring cell or histiocytoid appearance was observed in his left eyelid, orbit, and periocular lesion. Tumor cells expressed mucins and showed immunoreactivity that was similar to that of the Moll gland: MUC6 (+), GlcNAc alpha 1 -> 4Gal -> R(-), MUC2(-), MUC5AC(-), GCDFP15(+), CD15(+), S100(-), CK7(+), CK20(-), ER(+), PgR (+), HER2(-), E-cadherin(+), p63(-), PSA(-), and TTF-1(-). The tumor cells differed from those of perineal and axillary apocrine and eccrine sweat glands, which were MUC6(-). The Moll gland was ER(-) and PgR(-), whereas perineal and axillar apocrine sweat glands were ER(+) and PgR(+), and perineal and axillary eccrine sweat glands were ER(+) and PgR(-). The tumor showed characteristics similar to that of the eyelid Moll gland, which is demonstrated to be an apocrine gland with a protein expression distinct from that of other apocrine glands. MUC6 and GCDFP15 expression are useful in identifying the Moll gland immunophenotype and GCDFP15, ER and PgR expression are useful in distinguishing primary eyelid signet-ring/histocytoid carcinoma from gastrointestinal malignancies.ArticleAMERICAN JOURNAL OF DERMATOPATHOLOGY. 34(8):E139-E145 (2012)journal articl
A case of conjunctival intraepithelial neoplasia with spheroidal degeneration: a clinicopathological study
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