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151.
Magnetic resonance imaging (MRI) and boron-neutron capture therapy (BNCT) are quite attractive techniques for diagnosis and treatment of cancer, respectively. In order to progress the study on both MRI and BNCT, the novel compounds containing 19F and 10B atoms in a single molecule were designed and synthesized. In the present paper, the syntheses and the internalization rates into tumor cells of these compounds are elucidated.  相似文献   
152.
In adoptive immunotherapy, the number of effector cells is one of the major factors relating to the therapeutic efficacy. We demonstrated that tumor-infiltrating lymphocytes (TILs) were stimulated to proliferate by incubation with interleukin 2 (IL-2) plus interleukin 4 (IL-4). TILs cultured with IL-2 plus IL-4 increased 3.1-fold more than TILs cultured with IL-2 alone. However, IL-4 did not alter the cytotoxic activity of TILs against autologous tumor cells and established tumor cell lines. It is suggested that IL-2 receptor is related to the mechanism of the proliferation of activated TILs cultured by combination with IL-2 and IL-4. Thus, the combination of IL-2 and IL-4 may increase the efficacy of adoptive immunotherapy using activated TILs.  相似文献   
153.
The Golgi apparatus forms stacks of cisternae in many eukaryotic cells. However, little is known about how such a stacked structure is formed and maintained. To address this question, plant cells provide a system suitable for live-imaging approaches because individual Golgi stacks are well separated in the cytoplasm. We established tobacco BY-2 cell lines expressing multiple Golgi markers tagged by different fluorescent proteins and observed their responses to brefeldin A (BFA) treatment and BFA removal. BFA treatment disrupted cis, medial, and trans cisternae but caused distinct relocalization patterns depending on the proteins examined. Medial- and trans-Golgi proteins, as well as one cis-Golgi protein, were absorbed into the endoplasmic reticulum (ER), but two other cis-Golgi proteins formed small punctate structures. After BFA removal, these puncta coalesced first, and then the Golgi stacks regenerated from them in the cis-to-trans order. We suggest that these structures have a property similar to the ER-Golgi intermediate compartment and function as the scaffold of Golgi regeneration.  相似文献   
154.
Polycomb repressive complex 1 (PRC1) plays an essential role in the epigenetic repression of gene expression during development and cellular differentiation via multiple effector mechanisms, including ubiquitination of H2A and chromatin compaction. However, whether it regulates the stepwise progression of adipogenesis is unknown. Here, we show that FBXL10/KDM2B is an anti-adipogenic factor that is up-regulated during the early phase of 3T3-L1 preadipocyte differentiation and in adipose tissue in a diet-induced model of obesity. Interestingly, inhibition of adipogenesis does not require the JmjC demethylase domain of FBXL10, but it does require the F-box and leucine-rich repeat domains, which we show recruit a noncanonical polycomb repressive complex 1 (PRC1) containing RING1B, SKP1, PCGF1, and BCOR. Knockdown of either RING1B or SKP1 prevented FBXL10-mediated repression of 3T3-L1 preadipocyte differentiation indicating that PRC1 formation mediates the inhibitory effect of FBXL10 on adipogenesis. Using ChIP-seq, we show that FBXL10 recruits RING1B to key specific genomic loci surrounding the key cell cycle and the adipogenic genes Cdk1, Uhrf1, Pparg1, and Pparg2 to repress adipogenesis. These results suggest that FBXL10 represses adipogenesis by targeting a noncanonical PRC1 complex to repress key genes (e.g. Pparg) that control conversion of pluripotent cells into the adipogenic lineage.  相似文献   
155.
The wheat ALMT1 gene encodes an aluminum (Al)-activated malate transport protein which confers Al-resistance. We investigated the membrane topology of this plasma-membrane localized protein with immunocytochemical techniques. Several green fluorescent protein (GFP)-fused and histidine (His)-tagged chimeras of ALMT1 were prepared based on a computer-predicted secondary structure and transiently expressed in cultured mammalian cells. Antibodies raised to polypeptide epitopes of ALMT1 were used in conjunction with the antibody to the His-tags to determine the topology of ALMT1. This study shows that the ALMT1 protein contains six transmembrane domains with the amino and carboxyl termini located on the extracellular side of the plasma membrane.Key Words: ALMT1, aluminum resistance, immunofluorescent staining, malate transporter, topology, Triticum aestivum  相似文献   
156.
[Arg8]Vasopressin (AVP) has an antilipolytic action on adipocytes, but little is known about the mechanisms involved. Here, we examined the involvement of the V1a receptor in the antilipolytic effect of AVP using V1a receptor-deficient (V1aR-/-) mice. The levels of blood glycerol were increased in V1aR-/- mice. The levels of ketone bodies, such as acetoacetic acid and 3-hydroxybutyric acid, the products of the lipid metabolism, were increased in V1aR-/- mice under a fasting condition. Triacylglyceride and free fatty acid levels in blood were decreased in V1aR-/- mice. Furthermore, measurements with tandem mass spectrometry determined that carnitine and acylcarnitines in serum, the products of beta-oxidation, were increased in V1aR-/- mice. Most acylcarnitines were increased in V1aR-/- mice, especially in the case of 2-carbon (C2), C10:1, C10, C14:1, C16, C18:1, and hydroxy-18:1-carbon (OH-C18:1)-acylcarnitines under feeding rather than under fasting conditions. The analysis of tissue C2-acylcarnitine level showed that beta-oxidation was promoted in muscle under the feeding condition and in liver under the fasting condition. An in vitro assay using brown adipocytes showed that the cells of V1aR-/- mice were more sensitive to isoproterenol for lipolysis. These results suggest that the lipid metabolism is enhanced in V1aR-/- mice. The cAMP level was enhanced in V1aR-/- mice in response to isoproterenol. The phosphorylation of Akt by insulin stimulation was reduced in V1aR-/- mice. These results suggest that insulin signaling is suppressed in V1aR-/- mice. In addition, the total bile acid, taurine, and cholesterol levels in blood were increased, and an enlargement of the cholecyst was observed in V1aR-/- mice. These results indicated that the production of bile acid was enhanced by the increased level of cholesterol and taurine. Therefore, these results indicated that AVP could modulate the lipid metabolism by the antilipolytic action and the synthesis of bile acid via the V1a receptor.  相似文献   
157.
The mycotoxin deoxynivalenol (DON), a secondary metabolite produced by species of the plant pathogen Fusarium, causes serious problems in cereal crop production because of its toxicity towards humans and livestock. A biological approach for the degradation of DON using a DON-degrading bacterium (DDB) appears to be promising, although information about DDBs is limited. We isolated 13 aerobic DDBs from a variety of environmental samples, including field soils and wheat leaves. Of these 13 strains, nine belonged to the Gram-positive genus Nocardioides and other four to the Gram-negative genus Devosia. The degradation phenotypes of the two Gram types were clearly different; all washed cells of the 13 strains degraded 100 μg mL(-1) DON to below the detection limit (0.5 μg mL(-1)), but the conditions inducing the DON-degrading activities differed between the two Gram types. The HPLC profiles of the DON metabolites were also distinct between the two genera, although all strains produced 3-epi-deoxynivalenol. The Gram-positive strains showed DON assimilation in media containing DON as a carbon source, whereas the Gram-negatives did not. Our results suggest that aerobic DDBs are distributed within at least two phylogenetically restricted genera, suggesting independent evolution of the DON-degradation mechanisms.  相似文献   
158.
Strenuous exercise induces delayed-onset muscle damage including oxidative damage of cellular components. Oxidative stress to muscle cells impairs glucose uptake via disturbance of insulin signaling pathway. We investigated glucose uptake and insulin signaling in relation to oxidative protein modification in muscle after acute strenuous exercise. ICR mice were divided into sedentary and exercise groups. Mice in the exercise group performed downhill running exercise at 30 m/min for 30 min. At 24 hr after exercise, metabolic performance and insulin-signaling proteins in muscle tissues were examined. In whole body indirect calorimetry, carbohydrate utilization was decreased in the exercised mice along with reduction of the respiratory exchange ratio compared to the rested control mice. Insulin-stimulated uptake of 2-deoxy-[(3)H]glucose in damaged muscle was decreased after acute exercise. Tyrosine phosphorylation of insulin receptor substrate (IRS)-1 and phosphatidyl-3-kinase/Akt signaling were impaired by exercise, leading to inhibition of the membrane translocation of glucose transporter 4. We also found that acute exercise caused 4-hydroxy-nonenal modification of IRS-1 along with elevation of oxidative stress in muscle tissue. Impairment of insulin-induced glucose uptake into damaged muscle after strenuous exercise would be related to disturbance of insulin signal transduction by oxidative modification of IRS-1.  相似文献   
159.
In the adult teleost brain, proliferating cells are observed in a broad area, while these cells have a restricted distribution in adult mammalian brains. In the adult teleost optic tectum, most of the proliferating cells are distributed in the caudal margin of the periventricular gray zone (PGZ). We found that the PGZ is largely divided into 3 regions: 1 mitotic region and 2 post-mitotic regions—the superficial and deep layers. These regions are distinguished by the differential expression of several marker genes: pcna, sox2, msi1, elavl3, gfap, fabp7a, and s100β. Using transgenic zebrafish Tg (gfap:GFP), we found that the deep layer cells specifically express gfap:GFP and have a radial glial morphology. We noted that bromodeoxyuridine (BrdU)-positive cells in the mitotic region did not exhibit glial properties, but maintained neuroepithelial characteristics. Pulse chase experiments with BrdU-positive cells revealed the presence of self-renewing stem cells within the mitotic region. BrdU-positive cells differentiate into glutamatergic or GABAergic neurons and oligodendrocytes in the superficial layer and into radial glial cells in the deep layer. These results demonstrate that the proliferating cells in the PGZ contribute to neuronal and glial lineages to maintain the structure of the optic tectum in adult zebrafish.  相似文献   
160.
A novel endonuclease, a new member of the RAD2 nuclease family, has been identified from the higher plant, rice (Oryza sativa L. cv. Nipponbare), and designated as OsSEND-1. The open reading frame of the OsSEND-1 cDNA encoded a predicted product of 641 amino acid residues with a molecular weight of 69.9 kDa. The encoded protein showed a relatively high degree of sequence homology with the RAD2 nuclease family proteins, especially RAD2 nuclease, but it differed markedly from FEN-1, XPG or HEX1/EXO1. The N- and I-domains in the family were highly conserved in the OsSEND-1 sequence. The protein was much smaller than XPG, but larger than HEX1/EXO1 and FEN-1. The genome sequence was composed of 14 exons, and was localized at the almost terminal region of the short arm of chromosome 8. Northern blotting and in situ hybridization analyses demonstrated preferential expression of OsSEND-1 mRNA in proliferating tissues such as meristem. The mRNA level of OsSEND-1 was induced by UV and DNA-damaging agent such as MMS or H2O2, indicating that OsSEND-1 has some roles in the repair of many types of damaged DNA. The recombinant peptide showed endonuclease activity.  相似文献   
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