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1.
The efficacy of synthetic female sex pheromone lures for Crocidolomia pavonana (Fabricius) (Lepidoptera: Crambidae) in the cabbage fields of Java and Bali, Indonesia, was investigated by varying the composition and dosage of the components. The lure containing a synthetic pheromone blend of (Z)-11-hexadecenyl acetate (Z11–16: Ac) and (Z)-9-tetradecenyl acetate (Z9–14: Ac) at a 10:1 ratio acquired significantly more male catches than single component lures and the control lure. Meanwhile, no attraction was observed when lures with 1:1 and 1:10 blends were tested. The composition of Z11–16: Ac and Z9–14: Ac at a ratio of 5, 10 and 20:1 attracted more males than the control lures. Dosage studies showed that 0.055 and 0.55 mg of a mixture of Z11–16: Ac and Z9–14: Ac (10:1 ratio) attracted more males than the control. These results are the first demonstration of the efficacy of synthetic pheromone for C. pavonana in field conditions. The present study suggests the feasibility of pheromone-based monitoring as a simple and low-cost technique for integrated pest management of this pest.  相似文献   
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We recently established mouse microglial cells persistently infected with mouse-adapted scrapie ME7 (ScMG20/ME7) for in vitro study of prion pathogenesis. Here, we found that ScMG20/ME7 cells were hypersensitive to P2X7 receptor agonists, as demonstrated by sustained Ca(2+) influx, membrane pore formation, cell death, and interleukin-1beta release. P2X7 mRNA expression was upregulated in these cells, and also in scrapie-infected mice brains. Treatment with pentosan polysulfate eliminated the infectivity and disease-related forms of prion protein from ScMG20/ME7 cell cultures, however, hypersensitivity of P2X7 receptors remained. These results suggest that prion infections may strongly affect the P2X7 receptor system in mouse microglial cells.  相似文献   
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Because a limited study previously showed that alpha-synuclein (alpha-syn), the major pathogenic protein for Parkinson disease, was expressed in differentiating brain tumors as well as various peripheral cancers, the main objective of the present study was to determine whether alpha-syn might be involved in the regulation of tumor differentiation. For this purpose, alpha-syn and its non-amyloidogenic homologue beta-syn were stably transfected to human osteosarcoma MG63 cell line. Compared with beta-syn-overexpressing and vector-transfected cells, alpha-syn-overexpressing cells exhibited distinct features of differentiated osteoblastic phenotype, as shown by up-regulation of alkaline phosphatase and osteocalcin as well as inductive matrix mineralization. Further studies revealed that proteasome activity was significantly decreased in alpha-syn-overexpressing cells compared with other cell types, consistent with the fact that proteasome inhibitors stimulate differentiation of various osteoblastic cells. In alpha-syn-overexpressing cells, protein kinase C (PKC) activity was significantly decreased, and reactivation of PKC by phorbol ester significantly restored the proteasome activity and abrogated cellular differentiation. Moreover, activity of lysosome was up-regulated in alpha-syn-overexpressing cells, and treatment of these cells with autophagy-lysosomal inhibitors resulted in a decrease of proteasome activity associated with up-regulation of alpha-syn expression, leading to enhance cellular differentiation. Taken together, these results suggest that the stimulatory effect of alpha-syn on tumor differentiation may be attributed to down-regulation of proteasome, which is further modulated by alterations of various factors, such as protein kinase C signaling pathway and a autophagy-lysosomal degradation system. Thus, the mechanism of alpha-syn regulation of tumor differentiation and neuropathological effects of alpha-syn may considerably overlap with each other.  相似文献   
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Transection of the medial forebrain bundle caused apoptosis of dopamine neurons in the rat substantia nigra. Immunohistochemical localization of activated microglia and tyrosine hydroxylase in the axotomized substantia nigra showed that activation of microglia was rapid and OX-6 (MHC-II marker)-positive and ED1 (lysosomal phagocytic marker)-positive microglia were apposed to structurally intact tyrosine hydroxylase-positive dopamine neurons, indicating microglial phagocytosis of degenerating dopamine neurons. The occurrence of microglial phagocytosis at early stages of apoptosis may indicate the evolution of apoptosis into an irreversible state. Alternatively, interventions that suppress early activation of microglia might lead to novel mechanisms for neuron protection.  相似文献   
6.
Manggur, which means to plane down or sharpen, is a manual process in producing copper blades of Balinese gamelan orchestra. The craftsmen of Manggur work 6 to 8 hours a day, sitting on the floor with folded legs and hunched back. Because the craftsmen often complain about musculoskeletal problems after having completed a full day work, an ergonomic intervention was made by changing their usual working posture (the first working posture) into working on tables while sitting on chairs for one hour and alternately standing for half an hour (the second working posture). Treatment by subject design was applied to 22 randomly chosen craftsmen. Resting heart rate and working heart rate were measured by using a stopwatch, and the number of musculoskeletal complaints were recorded with Nordic Body Map Questionnaire. As a result, the second working posture caused significant reductions in working heart rate, work pulse (the difference between working heart rate and resting heart rate) and the number of musculoskeletal complaints. These results suggest that the change of working posture in manggur decreases cardiovascular load and musculoskeletal strain among Balinese gamelan craftsmen.  相似文献   
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As the first step in understanding the molecular oscillation of the circa rhythms in the golden rabbitfish Siganus guttatus—a reef fish with a definite lunar-related rhythmicity—we cloned and sequenced a Period gene (rfPer). The rfPer gene contained an open reading frame that encodes a protein consisting of 1,452 amino acids; this protein is highly homologous to PER proteins of vertebrates including zebrafish. Phylogenetic analyses indicated that the rfPER protein is related to the zebrafish PER1 and PER4. The expression of rfPer mRNA in the whole brain, retina, and liver under light/dark (LD) conditions increased at 06:00 h and decreased at 18:00 h, suggesting that its robust circadian rhythm occurs in neural and peripheral tissues. When daily variation in the expression in rfPer mRNA in the whole brain and cultured pineal gland were examined under LD conditions, similar expression patterns of the gene were observed with an increase around dawn. Under constant light condition, the increased expression of rfPer mRNA in the whole brain disappeared around dawn. The present results demonstrate that rfPer is related to zPer4 and possibly zPer1. The present study is the first report on the Period gene from a marine fish.  相似文献   
9.
Poly(3-hydroxybutyrate-co-38 mol%-3-hydroxyvalerate) [P(3HB-co-38mol%-3HV)] was produced by Cupriavidus sp. USMAA2-4 in the presence of oleic acid and 1-pentanol. Due to enormous production of empty fruit bunch (EFB) in the oil palm plantation and high production cost of P(3HB-co-3HV), oil palm EFB fibers were used for biocomposites preparation. In this study, maleic anhydride (MA) and benzoyl peroxide (DBPO) were used to improve the miscibility between P(3HB-co-3HV) and EFB fibers. Introduction of MA into P(3HB-co-3HV) backbone reduced the molecular weight and improved the thermal stability of P(3HB-co-3HV). Thermal stability of P(3HB-co-3HV)/EFB composites was shown to be comparable to that of commercial packaging product. Composites with 35% EFB fibers content have the highest tensile strength compared to 30% and 40%. P(3HB-co-3HV)/EFB blends showed less chemicals leached compared to commercial packaging.  相似文献   
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