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Yamazaki S Dudziak D Heidkamp GF Fiorese C Bonito AJ Inaba K Nussenzweig MC Steinman RM 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(10):6923-6933
Foxp3(+)CD25(+)CD4(+) regulatory T cells (Treg) mediate immunological self-tolerance and suppress immune responses. A subset of dendritic cells (DCs) in the intestine is specialized to induce Treg in a TGF-beta- and retinoic acid-dependent manner to allow for oral tolerance. In this study we compare two major DC subsets from mouse spleen. We find that CD8(+) DEC-205/CD205(+) DCs, but not the major fraction of CD8(-) DC inhibitory receptor-2 (DCIR2)(+) DCs, induce functional Foxp3(+) Treg from Foxp3(-) precursors in the presence of low doses of Ag but without added TGF-beta. CD8(+)CD205(+) DCs preferentially express TGF-beta, and the induction of Treg by these DCs in vitro is blocked by neutralizing Ab to TGF-beta. In contrast, CD8(-)DCIR2(+) DCs better induce Foxp3(+) Treg when exogenous TGF-beta is supplied. In vivo, CD8(+)CD205(+) DCs likewise preferentially induce Treg from adoptively transferred, Ag-specific DO11.10 RAG(-/-) Foxp3(-)CD4(+) T cells, whereas the CD8(-)DCIR2(+) DCs better stimulate natural Foxp3(+) Treg. These results indicate that a subset of DCs in spleen, a systemic lymphoid organ, is specialized to differentiate peripheral Foxp3(+) Treg, in part through the endogenous formation of TGF-beta. Targeting of Ag to these DCs might be useful for inducing Ag-specific Foxp3(+) Treg for treatment of autoimmune diseases, transplant rejection, and allergy. 相似文献
34.
Rice plant development: from zygote to spikelet 总被引:27,自引:0,他引:27
Itoh J Nonomura K Ikeda K Yamaki S Inukai Y Yamagishi H Kitano H Nagato Y 《Plant & cell physiology》2005,46(1):23-47
Rice is becoming a model plant in monocotyledons and a model cereal crop. For better understanding of the rice plant, it is essential to elucidate the developmental programs of the life cycle. To date, several attempts have been made in rice to categorize the developmental processes of some organs into substages. These studies are based exclusively on the morphological and anatomical viewpoints. Recent advancement in genetics and molecular biology has given us new aspects of developmental processes. In this review, we first describe the phasic development of the rice plant, and then describe in detail the developmental courses of major organs, leaf, root and spikelet, and specific organs/tissues. Also, for the facility of future studies, we propose a staging system for each organ. 相似文献
35.
Transcriptional induction of Smurf2 ubiquitin ligase by TGF-beta 总被引:1,自引:0,他引:1
Ohashi N Yamamoto T Uchida C Togawa A Fukasawa H Fujigaki Y Suzuki S Kitagawa K Hattori T Oda T Hayashi H Hishida A Kitagawa M 《FEBS letters》2005,579(12):2557-2563
Smad ubiquitination regulatory factor 2 (Smurf2), a ubiquitin ligase for Smads, plays critical roles in the regulation of transforming growth factor-beta (TGF-beta)-Smad signaling via ubiquitin-dependent degradation of Smad2 and Smad7. We found that TGF-beta stimulates Smurf2 expression. TGF-beta activated the Smurf2 promoter in a TGF-beta responsive cell lines, whereas IL-1alpha, PDGF and epidermal growth factor did not. TGF-beta-mediated Smurf2 promoter activation was inhibited by Smad7 or an activin receptor-like kinase 5 inhibitor but not by dominant negative Smad or disruption of Smad-binding elements in the promoter. Moreover, inhibition of the phosphatidil inositol 3 kinase (PI3K)/Akt pathway suppressed TGF-beta-mediated Smurf2 induction. These results suggest that TGF-beta stimulates Smurf2 expression by Smad-independent pathway such as PI3K/Akt pathway via TGF-beta receptor. 相似文献
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Tanaka M Sagawa S Hoshi J Shimoma F Yasue K Ubukata M Ikemoto T Hase Y Takahashi M Sasase T Ueda N Matsushita M Inaba T 《Bioorganic & medicinal chemistry》2006,14(17):5781-5794
Conformationally restricted 3-anilino-4-(3-indolyl)maleimide derivatives were designed and synthesized aiming at discovery of novel protein kinase Cbeta (PKCbeta)-selective inhibitors possessing oral bioavailability. Among them, compounds having a fused five-membered ring at the indole 1,2-position inhibited PKCbeta2 with IC50 of nM-order and showed good oral bioavailability. One of the most potent compounds was found to be PKCbeta-selective over other 6 isozymes and exhibited ameliorative effects in a rat diabetic retinopathy model via oral route. 相似文献
38.
Yoshizawa Itsuo Nagata Kyoko Ohuchi Ryoko Itoh Shinji Kanaiwa Yoshio Amiya Takashi 《Steroids》1980,36(1):87-96
Two D-homosteroids were isolated from the hydrolyzate of 5β-pregnane -3α,20α-diol disulfate (II) when it was refluxed in 3N hydrochloric acid. The structures of these steroids have been elucidated as 17α-methyl-D-homo-5β-androstane-3α, 17aβ-diol (VI) and 17α-methyl-17aγb-chloro-D-homo-5β-androstan-3α-ol (VIII) by instrumental analyses. The former was identical with a synthetic specimen derived from 5β-pregnane-3α,20β-diol di-sulfate (IV) by uranediol rearrangement. The main hydrolyzates obtained were 17α-ethyl-17β-methyl-18-nor-5β-androst-13-en-3α-ol (V) and 5β-pregnane-3α, 20α-diol (III). 相似文献
39.
Kyoko Fujisawa Charlotte Silcott-Niles Poppy Simonson Daniela Lamattina Cristian A. Humeres Tapan Bhattacharyya Pascal Mertens Caroline Thunissen Victoria ORourke Magdalena Paczuk James A. Whitworth Oscar Daniel Salomn Michael A. Miles 《PLoS neglected tropical diseases》2021,15(7)
BackgroundVisceral leishmaniasis (VL) is a zoonotic protozoal vector-borne disease that is a major public health challenge. In Argentina, canine (CVL) and human visceral leishmaniasis (HVL) have recently emerged. There is a lack of standardised diagnostic tests for CVL, which hinders control of CVL and HVL.Methodology/Principal findingsSampling was carried out in Puerto Iguazú, Argentina, comprising 190 asymptomatic, oligosymptomatic and polysymptomatic dogs. The following diagnostics were applied: microscopy of lymph node aspirate (LNA); three immunochromatographic rapid diagnostic tests (RDTs), prototype rK28-ICT, rK39-ICT (both Coris BioConcept), commercial rK39 (InBios); ELISA for IgG, IgG1 and IgG2, against rK28, rK39 or crude lysate antigen. DNA detection and analysis, with 30 dogs, was of the ITS1 region using skin samples, and loop-mediated isothermal amplification (LAMP; Eiken Loopamp) of buffy coat, skin scrape or LNA. 15.4% of dogs were positive by LNA microscopy. The rK28 RDT had higher seropositivity rate (61%) than either a prototype rK39 RDT (31.4%) or commercial rK39 RDT (18.8%), without cross-reactivity with six other pathogens. IgG anti-rK39 ELISA antibody titres, but not IgG2, were positively correlated with number of clinical signs. LAMP with LNA had a higher positivity rate than PCR; buffy coat sampling was more sensitive than skin scrape. ITS1 confirmed Leishmania (Leishmania) infantum as the agent of CVL. Leishmania (Viannia) spp. was detected in skin samples from two dogs, compatible with Leishmania (Viannia) braziliensis.Conclusions/SignificanceSeroprevalence confirmed rapid increase in CVL in Puerto Iguazú. The rK28 RDT test potentially has great value for improved point-of-care diagnosis. Given cost reduction and accessibility, commercial LAMP may be applicable to buffy coat. RDT biomarkers of CVL clinical status are required to combat spread of CVL and HVL. The presence of Viannia, perhaps as an agent of human mucocutaneous leishmaniasis (MCL), highlights the need for vigilance and surveillance. 相似文献
40.
Antitumor agents. 258. Syntheses and evaluation of dietary antioxidant--taxoid conjugates as novel cytotoxic agents 总被引:1,自引:0,他引:1
Nakagawa-Goto K Yamada K Nakamura S Chen TH Chiang PC Bastow KF Wang SC Spohn B Hung MC Lee FY Lee FC Lee KH 《Bioorganic & medicinal chemistry letters》2007,17(18):5204-5209
Various dietary antioxidants, including vitamins, flavonoids, curcumin, and a coumarin, were conjugated with paclitaxel (1) through an ester linkage. The newly synthesized compounds were evaluated for cytotoxic activity against several human tumor cell lines as well as the corresponding normal cell lines. Interestingly, most tested conjugates selectively inhibited the growth of 1A9 (ovarian) and KB (nasopharyngeal) tumor cells without activity against other cell lines. Particularly, conjugates 16 and 20 were highly active against 1A9 (ED(50) value of 0.005 microg/mL) as well as KB (ED(50) values of 0.005 and 0.14 microg/mL, respectively) cells. Compound 22b, the glycinate ester salt of vitamin E conjugated with 1, appears to be a promising lead for further development as a clinical trial candidate as it exhibited strong inhibitory activity against Panc-1 (pancreatic cancer) with less effect on the related E6E7 (normal) cell line. 相似文献