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71.
Monacolin K is a secondary metabolite produced by Monascus species. It was found that it is able to decrease cholesterol levels. In this study, red mold rice (RMR) was added to the diet of Arbor Acres broiler chickens, and the cholesterol level in meat, as well as the concentration of triglyceride, the high-density lipoprotein cholesterol (HDL-C), and the low-density lipoprotein cholesterol (LDL-C) in the serum were evaluated. Four-week-old broilers are studied and divided into four groups in that each group contains 15 subjects. A 3-week experimental feeding trial was conducted in which three groups of broilers were fed 2.0, 5.0, and 8.0% of RMR (RMR groups) within their diet, respectively, and the result was compared to the control group. The results indicated that for each RMR group, the cholesterol content was significantly lower than that of the control group; in addition, their meat products contain higher level of unsaturated fatty acids. Triglyceride and cholesterol concentration in serum was also found to be considerably lower in RMR groups when compared to control group. Finally, in RMR groups, HDL-C/LDL-C and HDL-C/cholesterol ratios were all higher than those of the control group. In short, the results demonstrated that the cholesterol levels could be lowered by adding RMR to the diet of chickens.  相似文献   
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BACKGROUND: Phagocytosis of cells undergoing apoptosis is essential during development, cellular turnover, and wound healing. Failure to promptly clear apoptotic cells has been linked to autoimmune disorders. C. elegans CED-12 and mammalian ELMO are evolutionarily conserved scaffolding proteins that play a critical role in engulfment from worm to human. ELMO functions together with Dock180 (a guanine nucleotide exchange factor for Rac) to mediate Rac-dependent cytoskeletal reorganization during engulfment and cell migration. However, the components upstream of ELMO and Dock180 during engulfment remain elusive. RESULTS: Here, we define a conserved signaling module involving the small GTPase RhoG and its exchange factor TRIO, which functions upstream of ELMO/Dock180/Rac during engulfment. Complementary studies in C. elegans show that MIG-2 (which we identify as the homolog of mammalian RhoG) and UNC-73 (the TRIO homolog) also regulate corpse clearance in vivo, upstream of CED-12. At the molecular level, we identify a novel set of evolutionarily conserved Armadillo (ARM) repeats within CED-12/ELMO that mediate an interaction with activated MIG-2/RhoG; this, in turn, promotes Dock180-mediated Rac activation and cytoskeletal reorganization. CONCLUSIONS: The combination of in vitro and in vivo studies presented here identify two evolutionarily conserved players in engulfment, TRIO/UNC73 and RhoG/MIG-2, and the TRIO --> RhoG signaling module is linked by ELMO/CED-12 to Dock180-dependent Rac activation during engulfment. This work also identifies ARM repeats within CED-12/ELMO and their role in linking RhoG and Rac, two GTPases that function in tandem during engulfment.  相似文献   
74.
An electric circuit for plant protoplast manipulation is described. The circuit used readily available materials and was designed for use in teaching. This integrated circuit can be placed in a single small box with controls for the aligning voltage, the aligning frequency, the pulse voltage, and the pulse timing. The circuit can be supplied by any suitable source of dc power and can be easily altered for individual requirements. The circuit, as presented here, can be assembled for less than $250.  相似文献   
75.
Global histone H1 phosphorylation correlates with cell cycle progression. However, the function of site-specific H1 variant phosphorylation remains unclear. Our mass spectrometry analysis revealed a novel N-terminal phosphorylation of the major H1 variant H1.4 at serine 35 (H1.4S35ph), which accumulates at mitosis immediately after H3 phosphorylation at serine 10. Protein kinase A (PKA) was found to be a kinase for H1.4S35. Importantly, Ser-35-phosphorylated H1.4 dissociates from mitotic chromatin. Moreover, H1.4S35A substitution mutant cannot efficiently rescue the mitotic defect following H1.4 depletion, and inhibition of PKA activity increases the mitotic chromatin compaction depending on H1.4. Our results not only indicate that PKA-mediated H1.4S35 phosphorylation dissociates H1.4 from mitotic chromatin but also suggest that this phosphorylation is necessary for specific mitotic functions.  相似文献   
76.
Summary Protein-tyrosine phosphatase PTPN3 is a membrane-associated non-receptor protein-tyrosine phosphatase. PTPN3 contains a N-terminal FERM domain, a middle PDZ domain, and a C-terminal phosphatase domain. Upon co-expression of PTPN3, the level of human hepatitis B viral (HBV) RNAs, 3.5 kb, 2.4/2.1 kb, and 0.7 kb transcribed from a replicating HBV expression plasmid is significantly reduced in human hepatoma HuH-7 cells. When the expression of endogenous PTPN3 protein is diminished by specific small interfering RNA, the expression of HBV genes is enhanced, indicating that the endogenous PTPN3 indeed plays a suppressive role on HBV gene expression. PTPN3 can interact with HBV core protein. The interaction is mediated via the PDZ domain of PTPN3 and the carboxyl-terminal last four amino acids of core. Either deletion of PDZ domain of PTPN3 or substitution of PDZ ligand in core has no effect on PTPN3-mediated suppression. These results clearly show that the interaction of PTPN3 with core is not required for PTPN3 suppressive effect. Mutation of 359serine and 835serine of 14-3-3β binding sites to alanine, which slightly reduces the interaction with 14-3-3β, does not influence the PTPN3 effect. In contrast, mutation of the invariant 842cysteine residue in phosphatase domain to serine, which makes the phosphatase activity inactive, does not change its subcellular localization and interaction with core or 14-3-3β, but completely abolishes PTPN3-mediated suppression. Furthermore, deletion of FERM domain does not affect the phosphatase activity or interaction with 14-3-3β, but changes the subcellular localization from cytoskeleton-membrane interface to cytoplasm and nucleus, abolishes binding to core, and diminishes the PTPN3 effect on HBV gene expression. Taken together, these results demonstrate that the phosphatase activity and FERM domain of PTPN3 are essential for its suppression of HBV gene expression. En-Chi Hsu, Yen-Cheng Lin have equal contributions to this work.  相似文献   
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79.
Kuruma shrimp Marsupenaeus japonicus held in 34 per thousand seawater were injected with tryptic soy broth (TSB)-grown Vibrio alginolyticus (2.7x10(6)cfu shrimp(-1)), and then placed in water containing concentrations of sulfide at 0 (control), 51, 106, 528 and 1050microgl(-1), respectively. After 12-144h, mortality of V. alginolyticus-injected shrimp exposed to 528 and 1102microgl(-1) sulfide was significantly higher than that of shrimp exposed to 51microgl(-1) sulfide and the control solution. In another experiment, M. japonicus which had been exposed to 0, 56, 112, 525 and 1076microgl(-1) sulfide for 6, 12, 24 and 48h were examined for immune parameters, and phagocytic activity and clearance efficiency of V. alginolyticus. Sulfide concentrations at 525microgl(-1) or greater for 12h resulted in decreased total haemocyte count (THC) and phenoloxidase activity, phagocytic activity and bacterial clearance efficiency, whereas a sulfide concentration at 1076microgl(-1) for 24h caused a significant increase in respiratory burst and superoxide dismutase activity of M. japonicus. It is concluded that concentrations of sulfide at 528microgl(-1) or greater increased the susceptibility of M. japonicus against V. alginolyticus infection by a depression in immune ability. The increased production of superoxide anion by M. japonicus exposed to 525microgl(-1) sulfide or greater was considered to be cytotoxic to the host.  相似文献   
80.

Background

Over-expression of Aurora kinases promotes the tumorigenesis of cells. The aim of this study was to determine the preclinical profile of a novel pan-Aurora kinase inhibitor, BPR1K653, as a candidate for anti-cancer therapy. Since expression of the drug efflux pump, MDR1, reduces the effectiveness of various chemotherapeutic compounds in human cancers, this study also aimed to determine whether the potency of BPR1K653 could be affected by the expression of MDR1 in cancer cells.

Principal Findings

BPR1K653 specifically inhibited the activity of Aurora-A and Aurora-B kinase at low nano-molar concentrations in vitro. Anti-proliferative activity of BPR1K653 was evaluated in various human cancer cell lines. Results of the clonogenic assay showed that BPR1K653 was potent in targeting a variety of cancer cell lines regardless of the tissue origin, p53 status, or expression of MDR1. At the cellular level, BPR1K653 induced endo-replication and subsequent apoptosis in both MDR1-negative and MDR1-positive cancer cells. Importantly, it showed potent activity against the growth of xenograft tumors of the human cervical carcinoma KB and KB-derived MDR1-positive KB-VIN10 cells in nude mice. Finally, BPR1K653 also exhibited favorable pharmacokinetic properties in rats.

Conclusions and Significance

BPR1K653 is a novel potent anti-cancer compound, and its potency is not affected by the expression of the multiple drug resistant protein, MDR1, in cancer cells. Therefore, BPR1K653 is a promising anti-cancer compound that has potential for the management of various malignancies, particularly for patients with MDR1-related drug resistance after prolonged chemotherapeutic treatments.  相似文献   
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