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1.
Hyuck Choi Byung-Chul Jeong Sung-Woong Hur Jung-Woo Kim Keun-Bae Lee Jeong-Tae Koh 《PloS one》2015,10(10)
Craniofacial bone defects are observed in a variety of clinical situations, and their reconstructions require coordinated coupling between angiogenesis and osteogenesis. In this study, we explored the effects of cartilage oligomeric matrix protein-angiopoietin 1 (COMP-Ang1), a synthetic and soluble variant of angiopoietin 1, on bone morphogenetic protein 2 (BMP2)-induced cranial bone regeneration, and recruitment and osteogenic differentiation of perivascular pericytes. A critical-size calvarial defect was created in the C57BL/6 mouse and COMP-Ang1 and/or BMP2 proteins were delivered into the defects with absorbable collagen sponges. After 3 weeks, bone regeneration was evaluated using micro-computed tomography and histologic examination. Pericyte recruitment into the defects was examined using immunofluorescence staining with anti-NG2 and anti-CD31 antibodies. In vitro recruitment and osteoblastic differentiation of pericyte cells were assessed with Boyden chamber assay, staining of calcified nodules, RT-PCR and Western blot analyses. Combined administration of COMP-Ang1 and BMP2 synergistically enhanced bone repair along with the increased population of CD31 (an endothelial cell marker) and NG2 (a specific marker of pericyte) positive cells. In vitro cultures of pericytes consistently showed that pericyte infiltration into the membrane pore of Boyden chamber was more enhanced by the combination treatment. In addition, the combination further increased the osteoblast-specific gene expression, including bone sialoprotein (BSP), osteocalcin (OCN) and osterix (OSX), phosphorylation of Smad/1/5/8, and mineralized nodule formation. COMP-Ang1 can enhance BMP2-induced cranial bone regeneration with increased pericyte recruitment. Combined delivery of the proteins might be a therapeutic strategy to repair cranial bone damage. 相似文献
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W. D. Roof H. Q. Fang K. D. Young Jianling Sun & Ry Young 《Molecular microbiology》1997,25(6):1031-1046
slyD encodes a 196 amino acid polypeptide that is a member of the FKBP family of cis–trans peptidyl–prolyl isomerases (PPIases). slyD mutations affect plaque formation by the phage φX174 by blocking the action of the phage lysis protein E. Here we describe the selection of a set of spontaneous slyD mutations conferring resistance to the expression of gene E from a plasmid. These mutations occur disproportionately in residues of SlyD that, based on the structure of the prototype mammalian FKBP12, make ligand contacts with immunosuppressing drug molecules or are conserved in other FKBP proteins. A wide variation in the plating efficiency of φX174 on these E R strains is observed, relative to the parental, indicating that these alleles differ widely in residual SlyD activity. Moreover, it is found that slyD mutations cause significant growth rate defects in Escherichia coli B and C backgrounds. Finally, overexpression of slyD causes filamentation of the host. Thus, among the FKBP genes found in organisms across the evolutionary spectrum, slyD is unique in having three distinct drug-independent phenotypes. 相似文献
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Eun Jin Park Joon Young Song Min Ju Choi Ji Ho Jeon Jah-yeon Choi Tae Un Yang Kyung Wook Hong Ji Yun Noh Hee Jin Cheong Woo Joo Kim 《The Korean journal of parasitology》2014,52(4):425-428
A 45-year-old-male who had underlying ulcerative colitis and presented with fever and dry cough. Initially, the patient was considered to have invasive aspergillosis due to a positive galactomannan assay. He was treated with amphotericin B followed by voriconazole. Nevertheless, the patient deteriorated clinically and radiographically. The lung biopsy revealed eosinophilic pneumonia, and ELISA for Toxocara antigen was positive, leading to a diagnosis of pulmonary toxocariasis. After a 10-day treatment course with albendazole and adjunctive steroids, the patient recovered completely without any sequelae. Pulmonary toxocariasis may be considered in patients with subacute or chronic pneumonia unresponsive to antibiotic agents, particularly in cases with eosinophilia. 相似文献
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Fatty acyl-CoAs are potential in vivo inactivators of glucose-6-phosphate dehydrogenase (G6PD). Ovariectomized mature rats (n = 74) were given 5 micrograms of estradiol intravenously, then killed 0, 24, 36, 48 and 72 h later. Control levels of myristoyl-, palmitoyl-, stearoyl-, arachidonoyl-, oleoyl- and linoleoyl-CoA were 0.6, 3.2, 4.7, 3.4, 2.4 and 3.0 micrograms/uterus and were increased 39, 110, 146, 100, 84 and 69% at 36-48 h, respectively. Levels of fatty acyl-CoAs in the rat uterus become elevated 36 h after estradiol treatment. At the same time G6PD changes from a stable enzyme to one that is irreversibly inactivated, possibly due to being rapidly degraded. Progesterone (2 mg subcutaneously every 12 h, n = 30), administered beginning at either 24 or 36 h after estradiol treatment, had no effect on estradiol-induced changes in myristoyl-, palmitoyl-, or stearoyl-CoA. Compared to the groups of rats treated with estradiol alone, animals treated with combinations of estradiol and progesterone exhibited higher levels of arachidonoyl-CoA after 48 h, and oleoyl-CoA and linoleoyl-CoA were greater after 72 h. Progesterone increased the estradiol-induced levels of unsaturated fatty acyl-CoAs suggesting that progesterone may induce uterine fatty acid desaturase activity and/or uptake of dietary fatty acids. Addition of fatty acyl-CoAs, at concentrations seen in vivo at 36-48 h after estradiol, to purified G6PD, causes irreversible G6PD inactivation. 相似文献
9.
J. Young 《BMJ (Clinical research ed.)》1996,313(7058):677-681
Rehabilitation is concerned with lessening the impact of disabling conditions. These are particularly common in older people and considerable health gain can be achieved by successful rehabilitation. Hospital doctors and general practitioners should be aware of the core principles of rehabilitation, be able to recognise rehabilitation need in their patients, and have sufficient knowledge of their local rehabilitation services to trigger the referral process. 相似文献
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