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991.
Jeung Il Kim Tae Wan Kim Sung Min Hong Tae Yong Moon In Sook Lee Kyung Un Choi Hak Sun Yu 《The Korean journal of parasitology》2014,52(1):69-73
Sparganosis is a parasitic infection caused by the plerocercoid tapeworm larva of the genus Spirometra. Although the destination of the larva is often a tissue or muscle in the chest, abdominal wall, extremities, eyes, brain, urinary tract, spinal canal, and scrotum, intramuscular sparganosis is uncommon and therefore is difficult to distinguish from a soft tissue tumor. We report a case of intramuscular sparganosis involving the gastrocnemius muscle in an elderly patient who was diagnosed using ultrasonography and MRI and treated by surgical excision. At approximately 1 cm near the schwannoma at the right distal sciatic nerve, several spargana worms were detected and removed. 相似文献
992.
The Furongian trilobite family Tsinaniidae is characterized by a highly effaced surface and forms an important constituent of the Furongian trilobite faunas of east Gondwana. However, the origin of the characteristic morphology of this family has remained unclear. Only recently has the tsinaniid trilobite Lonchopygella megaspina been suggested to represent an intermediate stage in the evolutionary transition to other tsinaniids on the basis of the trunk segmentation. Here, we report successive occurrences of four species of the kaolishaniid genus Mansuyia and a tsinaniid trilobite Tsinania canens from the Furongian (late Cambrian) Chaomidian Formation in Shandong Province, China. A cladistic analysis including these taxa reveals that the four species of Mansuyia constitute stem‐group taxa to the family Tsinaniidae, rendering Mansuyia and the Kaolishaniidae paraphyletic. The youngest species of Mansuyia, M. taianfuensis, turns out to be the immediate sister taxon of the Tsinaniidae, displaying a closely similar morphology to the tsinaniid trilobite, Shergoldia laevigata. The generic and familial boundary therefore situated between M. taianfuensis and S. laevigata. 相似文献
993.
994.
The industrially-important thermostable lipase, TliA, was extracellularly produced in the recombinant Pseudomonas fluorescens by the homologous expression of TliA and its cognate ABC protein exporter, TliDEF. To increase the secretory production of TliA, we optimized the growth temperature and the culture medium of P. fluorescens. The total amount and the specific productivity of lipase was highest at 25 °C of cell growth temperature, although maximal cell growth was observed at 30 °C. Using the culture medium composed of 20 g dextrin l?1, 40 g Tween 80 l?1 and 30 g peptone l?1, TliA was produced at a level of 2,200 U ml?1 in a flask culture. The TliA production increased about 3.8-fold (8,450 U ml?1) in batch fermentation using a 2.5 l fermentor, which was about 7.7-fold higher than that of previously reported TliA production. 相似文献
995.
Adriana M.G. Ibelli Tae K. Kim Creston C. Hill Lauren A. Lewis Mariam Bakshi Stephanie Miller Lindsay Porter Albert Mulenga 《International journal for parasitology》2014
Ixodes scapularis is a medically important tick species that transmits causative agents of important human tick-borne diseases including borreliosis, anaplasmosis and babesiosis. An understanding of how this tick feeds is needed prior to the development of novel methods to protect the human population against tick-borne disease infections. This study characterizes a blood meal-induced I. scapularis (Ixsc) tick saliva serine protease inhibitor (serpin (S)), in-house referred to as IxscS-1E1. The hypothesis that ticks use serpins to evade the host’s defense response to tick feeding is based on the assumption that tick serpins inhibit functions of protease mediators of the host’s anti-tick defense response. Thus, it is significant that consistent with hallmark characteristics of inhibitory serpins, Pichia pastoris-expressed recombinant IxscS-1E1 (rIxscS-1E1) can trap thrombin and trypsin in SDS- and heat-stable complexes, and reduce the activity of the two proteases in a dose-responsive manner. Additionally, rIxscS-1E1 also inhibited, but did not apparently form detectable complexes with, cathepsin G and factor Xa. Our data also show that rIxscS-1E1 may not inhibit chymotrypsin, kallikrein, chymase, plasmin, elastase and papain even at a much higher rIxscS-1E1 concentration. Native IxscS-1E1 potentially plays a role(s) in facilitating I. scapularis tick evasion of the host’s hemostatic defense as revealed by the ability of rIxscS-1E1 to inhibit adenosine diphosphate- and thrombin-activated platelet aggregation, and delay activated partial prothrombin time and thrombin time plasma clotting in a dose-responsive manner. We conclude that native IxscS-1E1 is part of the tick saliva protein complex that mediates its anti-hemostatic, and potentially inflammatory, functions by inhibiting the actions of thrombin, trypsin and other yet unknown trypsin-like proteases at the tick–host interface. 相似文献
996.
Byeong-Ho Kang Young-Jun Shim Yoo-Keung Tae Jin-A Song Byong-Kwan Choi In-Sun Park Bon-Hong Min 《Biochemical and biophysical research communications》2014
Clusterin induces the expression of various chemotactic cytokines including tumor necrosis factor-α (TNF-α) in macrophages and is involved in the cell migration. According to the results of this study, clusterin induced the directional migration (chemotaxis) of macrophages based on a checkerboard analysis. The chemotactic activity of clusterin was prevented by pretreatment with pertussis toxin (PTX), indicating that the Gαi/o-protein coupled receptor (GPCR) was involved in the chemotactic response of clusterin. Clusterin-stimulated chemotaxis was abrogated in a dose-dependent manner by pretreatment with gallein (a Gβγ inhibitor), indicating the involvement of Gβγ released from the GPCR. In addition, inhibitors of phospholipase C (PLC, U73122) and phosphoinositide 3-kinase (PI3K, LY294002), the key targets of Gβγ binding and activation, suppressed chemotactic migration by clusterin. The phosphorylation of Akt induced by clusterin was blocked by pretreatment with gallein or LY294002 but not with U73122, indicating that Gβγ released from the PTX-sensitive Gi protein complex activated PLC and PI3K/Akt signaling pathways separately. The activation of cellular MAP kinases was essential in that their inhibitors blocked clusterin-induced chemotaxis, and Gβγ was required for the activation of MAP kinases because gallein reduced their phosphorylations induced by clusterin. In addition, the inflammation-induced migration of macrophages was greatly reduced in clusterin-deficient mice based on a thioglycollate-induced peritonitis model system. These results suggest that clusterin stimulates the chemotactic migration of macrophages through a PTX-sensitive GPCR and Gβγ-dependent pathways and describe a novel role of clusterin as a chemoattractant of monocytes/macrophages, suggesting that clusterin may serve as a molecular bridge between inflammation and its remodeling of related tissue by recruiting immune cells. 相似文献
997.
998.
Tae Hoon Lee Shilpa Chennakrishnaiah Eric Audemard Laura Montermini Brian Meehan Janusz Rak 《Biochemical and biophysical research communications》2014
Cell free DNA is often regarded as a source of genetic cancer biomarkers, but the related mechanisms of DNA release, composition and biological activity remain unclear. Here we show that rat epithelial cell transformation by the human H-ras oncogene leads to an increase in production of small, exosomal-like extracellular vesicles by viable cancer cells. These EVs contain chromatin-associated double-stranded DNA fragments covering the entire host genome, including full-length H-ras. Oncogenic N-ras and SV40LT sequences were also found in EVs emitted from spontaneous mouse brain tumor cells. Disruption of acidic sphingomyelinase and the p53/Rb pathway did not block emission of EV-related oncogenic DNA. Exposure of non-transformed RAT-1 cells to EVs containing mutant H-ras DNA led to the uptake and retention of this material for an extended (30 days) but transient period of time, and stimulated cell proliferation. Thus, our study suggests that H-ras-mediated transformation stimulates vesicular emission of this histone-bound oncogene, which may interact with non-transformed cells. 相似文献
999.
Mi Hye Son Mi Young Jung Seulah Choi Daeho Cho Tae Sung Kim 《Biochemical and biophysical research communications》2014
Interleukin (IL)-32 has been associated with a variety of inflammatory diseases including rheumatoid arthritis, vasculitis and Crohn’s disease. We have previously reported that IL-32γ, the IL-32 isoform with the highest biological activity, could act as an immune modulator through regulation of dendritic cell (DC) functions in immune responses. Cell locomotion is crucial for induction of an effective immune response. In this study, we investigated the effect and underlying mechanisms of IL-32γ on recruitment of T cells. IL-32γ upregulated the expression of several chemokines including CCL2, CCL4, and CCL5 in the DCs. In particular, IL-32γ significantly increased CCL5 expression in a dose-dependent manner. Treatment with JNK and NF-κB inhibitors suppressed IL-32γ-induced CCL5 expression in DCs, indicating that IL-32γ induced CCL5 production through the JNK and NF-κB pathways. Furthermore, supernatants from IL-32γ-treated DCs showed chemotactic activities controlling migration of activated CD4+ and CD8+ T cells, and these activities were suppressed by addition of neutralizing anti-CCL5 antibody. These results show that IL-32γ effectively promotes migration of activated T cells via CCL5 production in DCs. The chemotactic potential of IL-32γ may explain the pro-inflammatory effects of IL-32 and the pathologic role of IL-32 in immune disorders such as rheumatoid arthritis. 相似文献
1000.
HIF‐1α Expression as a Protective Strategy of HepG2 Cells Against Fatty Acid‐Induced Toxicity 下载免费PDF全文