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11.
Cell morphogenesis is of fundamental significance in all eukaryotes for development, differentiation, and cell proliferation. In fission yeast, Drosophila Furry-like Mor2 plays an essential role in cell morphogenesis in concert with the NDR/Tricornered kinase Orb6. Mutations of these genes result in the loss of cell polarity. Here we show that the conserved proteins, MO25-like Pmo25, GC kinase Nak1, Mor2, and Orb6, constitute a morphogenesis network that is important for polarity control and cell separation. Intriguingly, Pmo25 was localized at the mitotic spindle pole bodies (SPBs) and then underwent translocation to the dividing medial region upon cytokinesis. Pmo25 formed a complex with Nak1 and was required for both the localization and kinase activity of Nak1. Pmo25 and Nak1 in turn were essential for Orb6 kinase activity. Further, the Pmo25 localization at the SPBs and the Nak1-Orb6 kinase activities during interphase were under the control of the Cdc7 and Sid1 kinases in the septation initiation network (SIN), suggesting a functional linkage between SIN and the network for cell morphogenesis/separation following cytokinesis.  相似文献   
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We studied the effect of transforming growth factor-beta 1 (TGF-beta 1) on colony formation of leukemic blast progenitors from ten acute myeloblastic leukemia (AML) patients stimulated with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), interleukin-6 (IL-6), or interleukin-1 beta (IL-1 beta). These CSFs and interleukins by themselves stimulated the proliferation of leukemic blast progenitors without adding TGF-beta 1. G-CSF, GM-CSF, and IL-3 stimulated blast colony formation in nine patients, IL-6 stimulated it in five, and IL-1 beta stimulated in four. TGF-beta 1 significantly reduced blast colony formation stimulated by G-CSF, GM-CSF, or IL-6 in all patients. In contrast, TGF-beta 1 enhanced the stimulatory effect of IL-3 on blast progenitors from three cases, while in the other seven patients TGF-beta 1 reduced blast colony formation in the presence of IL-3. To study the mechanism by which TGF-beta 1 enhanced the stimulatory effect of IL-3 on blast progenitors, we carried out the following experiments in the three patients in which it occurred. First, the media conditioned by leukemic cells in the presence of TGF-beta 1 stimulated the growth of leukemic blast progenitors, but such effect was completely abolished by anti-IL-1 beta antibody. Second, the addition of IL-1 beta in the culture significantly enhanced the growth of blast progenitors stimulated with IL-3. Third, leukemic cells of the two patients studied were revealed to secrete IL-1 beta and tumor necrosis factor-alpha (TNF-alpha) constitutively; the production by leukemic cells of IL-1 beta and TNF-alpha was significantly promoted by TGF-beta 1. Furthermore, the growth enhancing effect of TGF-beta 1 in the presence of IL-3 was fully neutralized by anti-IL-1 beta antibody. These findings suggest that TGF-beta 1 stimulated the growth of blast progenitors through the production and secretion of IL-1 beta by leukemic cells.  相似文献   
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We isolated and characterized a d-lactic acid-producing lactic acid bacterium (d-LAB), identified as Lactobacillus delbrueckii subsp. lactis QU 41. When compared to Lactobacillus coryniformis subsp. torquens JCM 1166 T and L. delbrueckii subsp. lactis JCM 1248 T, which are also known as d-LAB, the QU 41 strain exhibited a high thermotolerance and produced d-lactic acid at temperatures of 50 °C and higher. In order to optimize the culture conditions of the QU 41 strain, we examined the effects of pH control, temperature, neutralizing reagent, and initial glucose concentration on d-lactic acid production in batch cultures. It was found that the optimal production of 20.1 g/l d-lactic acid was acquired with high optical purity (>99.9% of d-lactic acid) in a pH 6.0-controlled batch culture, by adding ammonium hydroxide as a neutralizing reagent, at 43 °C in MRS medium containing 20 g/l glucose. As a result of product inhibition and low cell density, continuous cultures were investigated using a microfiltration membrane module to recycle flow-through cells in order to improve d-lactic acid productivity. At a dilution rate of 0.87 h−1, the high cell density continuous culture exhibited the highest d-lactic acid productivity of 18.0 g/l/h with a high yield (ca. 1.0 g/g consumed glucose) and a low residual glucose (<0.1 g/l) in comparison with systems published to date.  相似文献   
15.
5a-Carba-β-D-glucopyranose derivatives were synthesized and identified as novel SGLT2-selective inhibitors. These inhibitors exhibited potent SGLT2 inhibition with high selectivity over SGLT1. Among the tested compounds, 6f indicated the most potent hSGLT2 inhibition and the highest selectivity over hSGLT1. Moreover, the pharmacokinetics data also showed that 6h, which had the same aglycon structure as sergliflozin-active (3-active), had a threefold longer half-life time (T(1/2)) than sergliflozin (3) with a high distribution volume in db/db mice. Subsequently, 6h lowered blood glucose levels as much as 3 and showed longer hypoglycemic action than 3 in db/db mice.  相似文献   
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Regulation of food intake by acyl and des-acyl ghrelins in the goldfish   总被引:2,自引:0,他引:2  
Our recent research has indicated that intracerebroventricular (i.c.v.) and intraperitoneal (i.p.) administration of n-octanoic acid-modified ghrelin (acyl ghrelin) stimulates food intake and locomotor activity in the goldfish. The manner in which peripherally administered acyl ghrelin regulates food intake, however, remains unclear. In contrast to acyl ghrelin, non-acylated ghrelin (des-acyl ghrelin) does not exert an orexigenic action or induce hypermotility. To this extent, the biological role of des-acyl ghrelin in fish is unknown. Given the possible involvement of afferent pathways in mediating the effects of acyl ghrelin, as is known to occur in rodents, we examined the effect of capsaicin, a neurotoxin which destroys primary sensory (vagal and splanchnic) afferents, on the orexigenic activity induced by i.p.-injected acyl ghrelin. Pretreatment with i.p.-injected capsaicin (0.16 micromol/g body weight (BW)) cancelled the orexigenic action of i.p.-injected acyl ghrelin (8 pmol/g BW), although i.p.-injected capsaicin alone did not affect food intake. The effect of des-acyl ghrelin on the orexigenic action of acyl ghrelin in the goldfish was also investigated. The i.c.v. and i.p. injection of des-acyl ghrelin at doses 3-10 times higher than that of acyl ghrelin suppressed the orexigenic action of i.c.v.- and i.p.-injected acyl ghrelin (doses of 1 and 8 pmol/g BW). In contrast, injection of des-acyl ghrelin alone did not show any inhibitory effect on food intake. These results suggest that, as is seen in rodents, circulating acyl ghrelin derived from peripheral tissues acts via primary sensory afferent pathways on feeding centers in the brain. The results also show that des-acyl ghrelin inhibits acyl ghrelin-induced orexigenic activity in goldfish.  相似文献   
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The Trypanosoma spp. cause animal and human trypanosomiasis characterized with appreciable health and economic burden mostly in developing nations. There is currently no effective therapy for this parasitic disease, due to poor drug efficacy, drug resistance, and unwanted toxicity, etc. Therefore, new anti-Trypanosoma agents are urgently needed. This study explored new series of imidazoles for anti-Trypanosoma properties in vitro and in vivo. The imidazoles showed moderate to strong and specific action against growth of T. congolense. For example, the efficacy of the imidazole compounds to restrict Trypanosoma growth in vitro was ≥ 12-fold specific towards T. congolense relative to the mammalian cells. Additionally, the in vivo study revealed that the imidazoles exhibited promising anti-Trypanosoma efficacy corroborating the in vitro anti-parasite capacity. In particular, three imidazole compounds (C1, C6, and C8) not only cleared the systemic parasite burden but cured infected rats after no death was recorded. On the other hand, the remaining five imidazole compounds (C2, C3, C4, C5, and C7) drastically reduced the systemic parasite load while extending survival time of the infected rats by 14 days as compared with control. Untreated control died 3 days post-infection, while the rats treated with diminazene aceturate were cured comparable to the results obtained for C1, C6, and C8. In conclusion, this is the first study demonstrating the potential of these new series of imidazoles to clear the systemic parasite burden in infected rats. Furthermore, a high selectivity index of imidazoles towards T. congolense in vitro and the oral LD50 in rats support anti-parasite specific action. Together, findings support the anti-parasitic prospects of the new series of imidazole derivatives.  相似文献   
20.
The canga of the Serra dos Carajás, in Eastern Amazon, is home to a unique open plant community, harboring several endemic and rare species. Although a complete flora survey has been recently published, scarce to no genetic information is available for most plant species of the ironstone outcrops of the Serra dos Carajás. In this scenario, DNA barcoding appears as a fast and effective approach to assess the genetic diversity of the Serra dos Carajás flora, considering the growing need for robust biodiversity conservation planning in such an area with industrial mining activities. Thus, after testing eight different DNA barcode markers (matK, rbcL, rpoB, rpoC1, atpF‐atpH, psbK‐psbI, trnH‐psbA, and ITS2), we chose rbcL and ITS2 as the most suitable markers for a broad application in the regional flora. Here we describe DNA barcodes for 1,130 specimens of 538 species, 323 genera, and 115 families of vascular plants from a highly diverse flora in the Amazon basin, with a total of 344 species being barcoded for the first time. In addition, we assessed the potential of using DNA metabarcoding of bulk samples for surveying plant diversity in the canga. Upon achieving the first comprehensive DNA barcoding effort directed to a complete flora in the Brazilian Amazon, we discuss the relevance of our results to guide future conservation measures in the Serra dos Carajás.  相似文献   
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