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991.
Takeshi Nishimoto Yuki Yamamoto Kimiko Yoshida Naoko Goto Shumpei Ohnami Kazunori Aoki 《PloS one》2012,7(9)
The targeting of gene transfer at the cell-entry level is one of the most attractive challenges in vector development. However, attempts to redirect adenovirus vectors to alternative receptors by engineering the capsid-coding region have shown limited success, because the proper targeting ligands on the cells of interest are generally unknown. To overcome this limitation, we have constructed a random peptide library displayed on the adenoviral fiber knob, and have successfully selected targeted vectors by screening the library on cancer cell lines in vitro. The infection of targeted vectors was considered to be mediated by specific receptors on target cells. However, the expression levels and kinds of cell surface receptors may be substantially different between in vitro culture and in vivo tumor tissue. Here, we screened the peptide display-adenovirus library in the peritoneal dissemination model of AsPC-1 pancreatic cancer cells. The vector displaying a selected peptide (PFWSGAV) showed higher infectivity in the AsPC-1 peritoneal tumors but not in organs and other peritoneal tumors as compared with a non-targeted vector. Furthermore, the infectivity of the PFWSGAV-displaying vector for AsPC-1 peritoneal tumors was significantly higher than that of a vector displaying a peptide selected by in vitro screening, indicating the usefulness of in vivo screening in exploring the targeting vectors. This vector-screening system can facilitate the development of targeted adenovirus vectors for a variety of applications in medicine. 相似文献
992.
993.
994.
Moride N Kuwahara A Sutoh A Tanaka Y Mukai Y Yamashita M Matsuzaki T Yasui T Irahara M 《Zygote (Cambridge, England)》2012,20(2):193-198
It is reported that okadaic acid (OA)-sensitive phosphatase is related to mitogen-activated protein kinase (MAPK)/p90rsk activation in mammalian oocytes. OA is also involved in the positive feedback loop between M phase-promoting factor (MPF) and cdc25c in Xenopus oocytes during meiotic maturation. However, the effect of phosphatase inhibition by OA on MPF and MAPK activities at the MII/G1 in oocytes remains unknown. The aim of this study is to clarify the relationship between OA-sensitive phosphatase and mitosis MII/G1 transition in mouse oocytes. MII-arrested oocytes were, isolated from mice, inseminated and cultured in TYH medium (control group) or TYH medium supplemented with 2.5 μM of OA (OA group). Histone H1 kinase and myelin basic protein (MBP) kinase activities were measured as indicators of MPF and p42 MAPK activities after insemination. Phosphorylation of cdc25c after insemination was analized in OA and control group by western blotting. Seven hours after insemination a pronucleus (PN) was formed in 84.1% (69/85) of oocytes in the control group. However, no PN was formed in oocytes of the OA group (p < 0.001). Although MPF and MAPK activities in the control group significantly decreased at 3, 4, 5, and 7 h after insemination, these decreases were significantly inhibited by OA addition (p < 0.05). Furthermore, OA addition prevented cdc25c dephosphorylation 7 h after insemination. In conclusion, OA-sensitive phosphatase correlates with inactivation of MPF and MAPK, and with the dephosphorylation of cdc25c at the MII/G1 transition in mouse oocytes. 相似文献
995.
Chijiwa T Ikeda N Masuda H Hara H Oda-Ueda N Hattori S Ohno M 《Bioscience, biotechnology, and biochemistry》2012,76(3):551-558
A novel phospholipase A(2) (PLA(2)) gene, named PfPLA 6, was found in a 6,328-bp NIS-1(5')-a segment in the Protobothrops flavoviridis (Habu, Crotalinae) genome. A comparison of the aligned nucleotide sequences of Viperidae (Viperinae and Crotalinae) venom PLA(2) genes, including PfPLA 6, revealed the deletion of a 12-bp segment called S1EX 1 and a 55-bp segment called S2EX 1 in exon 1 and the interposition of a 219-bp segment called SINT 2 (SINE) in intron 2. A classification of Viperidae PLA(2) genes based on these structural modes indicated that the A-type genes (without SINE), including PfPLA 6, are evolutionarily ancestral to the B-type (Viperinae) and C-type (Crotalinae) PLA(2) genes (both with SINE). Since PfPLA 6 is a pseudogene, an active prototype of PfPLA 6 can be assumed to be the ancestral PLA(2) gene. Putative evolutionary processes from this A-type prototype PLA(2) gene to descendent PLA(2) genes are discussed. 相似文献
996.
Terauchi M Nagasato C Kajimura N Mineyuki Y Okuda K Katsaros C Motomura T 《Planta》2012,236(4):1013-1026
Plasmodesmata are intercellular bridges that directly connect the cytoplasm of neighboring cells and play a crucial role in cell-to-cell communication and cell development in multicellular plants. Although brown algae (Phaeophyceae, Heterokontophyta) are phylogenetically distant to land plants, they nevertheless possess a complex multicellular organization that includes plasmodesmata. In this study, the ultrastructure and formation of plasmodesmata in the brown alga Dictyota dichotoma were studied using transmission electron microscopy and electron tomography with rapid freezing and freeze substitution. D. dichotoma possesses plasma membrane-lined, simple plasmodesmata without internal endoplasmic reticulum (desmotubule). This structure differs from those in land plants. Plasmodesmata were clustered in regions with thin cell walls and formed pit fields. Fine proteinaceous "internal bridges" were observed in the cavity. Ultrastructural observations of cytokinesis in D. dichotoma showed that plasmodesmata formation began at an early stage of cell division with the formation of tubular pre-plasmodesmata within membranous sacs of the cytokinetic diaphragm. Clusters of pre-plasmodesmata formed the future pit field. As cytokinesis proceeded, electron-dense material extended from the outer surface of the mid region of the pre-plasmodesmata and finally formed the nascent cell wall. From these results, we suggest that pre-plasmodesmata are associated with cell wall development during cytokinesis in D. dichotoma. 相似文献
997.
Abe H Tominaga T Matsubara T Abe N Kishi S Nagai K Murakami T Araoka T Doi T 《The Journal of biological chemistry》2012,287(24):20430-20442
Activation of mesangial cells (MCs), which is characterized by induction of smooth muscle α-actin (SMA) expression, contributes to a key event in various renal diseases; however, the mechanisms controlling MC differentiation are still largely undefined. Activated Smad1 induced SMA in a dose-dependent manner in MCs. As a direct regulating molecule for SMA, we identified and characterized scleraxis (Scx) as a new phenotype modulator in advanced glycation end product (AGE)-exposed MCs. Scx physically associated with E12 and bound the E-box in the promoter of SMA and negatively regulated the AGE-induced SMA expression. Scx induced expression and secretion of bone morphogenetic protein 4 (BMP4), thereby controlling the Smad1 activation in AGE-treated MCs. In diabetic mice, Scx was concomitantly expressed with SMA in the glomeruli. Inhibitor of differentiation 1 (Id1) was further induced by extended treatment with AGE, thereby dislodging Scx from the SMA promoter. These data suggest that Scx and Id1 are involved in the BMP4-Smad1-SMA signal transduction pathway besides the TGFβ1-Smad1-SMA signaling pathway and modulate phenotypic changes in MCs in diabetic nephropathy. 相似文献
998.
This study was initiated to examine accumulation of cadmium (Cd) and other metals in kidney and liver in autopsy samples and
to compare the levels between those in an area with heavy Cd exposure and those in no-polluted areas in Japan. Data on Cd
and other metals in kidney (cortex and medulla) and liver in 95 cases (87 women and eight men; the exposed) in a Cd-polluted
area and 43 cases (21 women and 22 men; the controls) in non-polluted areas were cited from 15 previous publications to be
summarized together with six unpublished cases. Cd levels in kidney cortex and medulla were significantly lower in the exposed
(31.5 and 23.8 μg/g wet tissue as GM, respectively) than in the controls (82.7 and 36.4 μg/g, respectively), whereas Cd levels
in liver was higher in the exposed (60.2 μg/g) than in the controls (8.1 μg/g). Exposed women had lower Cd in the cortex (29.9 μg/g)
and medulla (22.7 μg/g) than exposed men (55.4 and 38.1 μg/g, respectively) as well as in cortex of control women (92.9 μg/g).
Comparison with worldwide data other than Japan for non-exposed populations [19.1, 9.3, and 1.3 μg/g in cortex, medulla, and
liver, respectively, as the inverse variance-weighted averages (IVWA) of GM values for each of 22 reports] suggests that the
levels for the non-exposed Japanese (123.3, 33.5, and 3.9 μg/g as IVWA) tended to be higher than the levels in other countries,
possibly reflecting high dietary Cd intake in the past. 相似文献
999.
The distributions of neuropeptides in paraffin-embedded tissue sections (PETS) of the eyestalk, brain, and thoracic ganglia of the shrimp Penaeus monodon were visualized by imaging mass spectrometry (IMS). Peptide signals were obtained from PETS without affecting morphological features. Twenty-nine neuropeptides comprising members of FMRFamide, SIFamides, crustacean hyperglycaemic hormone, orcokinin-related peptides, tachykinin-related peptides, and allatostatin A were detected and visualized. Among these findings we first identified tachykinin-related peptide as a novel neuropeptide in this shrimp species. We found that these neuropeptides were distributed at specific areas in the three neural organs. In addition, 28 peptide sequences derived from 4 types of constitutive proteins, including actin, histones, arginine kinase, and cyclophilin A were also detected. All peptide sequences were verified by liquid chromatography-tandem mass spectrometry. The use of IMS on acetic acid-treated PETS enabled us to identify peptides and obtain their specific localizations in correlation with the undisturbed histological structure of the tissue samples. 相似文献
1000.
Tomoya Yoshinari Atsushi Yaguchi Naoko Takahashi-Ando Makoto Kimura Haruo Takahashi Takashi Nakajima Yoshiko Sugita-Konishi Hiromichi Nagasawa & Shohei Sakuda 《FEMS microbiology letters》2008,284(2):184-190
The essential oil of German chamomile showed specific inhibition toward aflatoxin G1 (AFG1 ) production, and ( E )- and ( Z )-spiroethers were isolated as the active compounds from the oil. The ( E )- and ( Z )-spiroethers inhibited AFG1 production of Aspergillus parasiticus with inhibitory concentration 50% (IC50 ) values of 2.8 and 20.8 μM, respectively, without inhibiting fungal growth. Results of an O- methylsterigmatocystin (OMST) conversion study indicated that the spiroethers specifically inhibited the OMST to AFG1 pathway. A cytochrome P450 monooxygenase, CYPA, is known as an essential enzyme for this pathway. Because CYPA has homology with TRI4, a key enzyme catalyzing early steps in the biosynthesis of trichothecenes, the inhibitory actions of the two spiroethers against TRI4 reactions and 3-acetyldeoxynivalenol (3-ADON) production were tested. ( E ) - and ( Z ) - spiroethers inhibited the enzymatic activity of TRI4 dose-dependently and interfered with 3-ADON production by Fusarium graminearum , with IC50 values of 27.1 and 103 μM, respectively. Our results suggest that the spiroethers inhibited AFG1 and 3-ADON production by inhibiting CYPA and TRI4, respectively. 相似文献