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101.
CD59, a complement regulatory protein, controls choroidal neovascularization in a mouse model of wet-type age-related macular degeneration 总被引:6,自引:0,他引:6
Bora NS Kaliappan S Jha P Xu Q Sivasankar B Harris CL Morgan BP Bora PS 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(3):1783-1790
We have shown that membrane attack complex (MAC) formation via the activation of the alternative pathway plays a central role in the laser-induced choroidal neovascularization (CNV). This study was undertaken to understand the role of a complement regulatory protein, CD59, which controls MAC assembly and function, in this model. CNV was induced by laser photocoagulation in C57BL/6 and Cd59a(-/-) mice using an argon laser. Animals from each group were sacrificed on day 1, 3, 5, and 7 postlaser. Retinal pigment epithelium-choroid-scleral tissue was examined to determine the incidence and size of CNV complex, and semiquantitative RT-PCR and Western blot analysis for CD59a was studied. Recombinant soluble mouse CD59a-IgG2a fusion (rsCD59a-Fc) protein was injected via i.p. or intravitreal routes 24 h before laser. Our results demonstrated that CD59a (both mRNA and protein) was down-regulated during laser-induced CNV. Cd59a(-/-) mice developed CNV complex early in the disease process. Increased MAC deposition was also observed in these Cd59a(-/-) mice. Administration of rsCD59a-Fc inhibited the development of CNV complex in the mouse model by blocking MAC formation and also inhibited expression of angiogenic growth factors. These data provide strong evidence that CD59a plays a crucial role in regulating complement activation and MAC formation essential for the release of growth factors that drive the development of laser-induced CNV in mice. Thus, our results suggest that the inhibition of complement by soluble CD59 may provide a novel therapeutic alternative to current treatment. 相似文献
102.
A rapid expansion of fisheries is demanding an adequate supply of efficient, nutritious and inexpensive fish feed, because feed contributes highly to the cost of fish production. Shrimp head, a waste product from the shrimp export industry qualifies as an economical, abundant and good quality protein source for fish feeds. In the present work, shrimp head silage powder, which contained approximately 40% protein, was used as a substitute for fish flour. Four feeds, in the form of pellets, were prepared by substituting shrimp head silage for fish flour at 0%, 33.3%, 66.6% and 100% dietary levels. Other ingredients such as corn, soy, bovine blood, cassava and corn cob flours, soy oil, vitamin premix, salt, and other components also were used in the formulation. A commercial fish feed was used as the control. The proximate composition of these feeds did not differ significantly at p>0.05, except for the protein content of the control feed, which was about 30.6% versus 35.4-36.9% protein in the other diets. No significant differences (p>0.05 level) in weight and length of juveniles fed with the different feeds during a period of 60 days were observed. In all cases, an excellent correlation (0.9950-0.9996) between weight and length of juveniles was observed. No significant difference in growth of juveniles fed on R1, R2, R3, or R4, or the control feed, was observed. Similarly, the proximate analyses of the flesh of juveniles did not present significant differences (p>0.05). The result of the study indicates that the shrimp head silage could replace fish flour as an ingredient in tilapia feed with economic advantages and without sacrificing the quality of the feed. 相似文献
103.
Bora E Cankaya T Alpman A Karaca E Cogulu O Tekgul H Ozkinay F 《Genetic counseling (Geneva, Switzerland)》2007,18(1):71-75
Martsolf syndrome is an autosomal recessive syndrome characterized by microcephaly, mental retardation, cataract, hypogonadism and short stature. A seven-year-old boy was admitted to the hospital with growth retardation and difficulties in walking. His parents were first cousins. Bilateral lens extraction was performed during infancy because of congenital cataract. On physical examination he had short stature, microcephaly, micropthalmia, hypogonadism, mental retardation. Brain magnetic resonance imaging revealed alterations in the white matter. Up to date very few cases with this syndrome have been reported. This is the first case described in the Turkish population and may add valuable information to the literature. 相似文献
104.
Since the establishment of in vitro fertilization, it became evident that almost half of the couples failed to achieve fertilization and this phenomenon was attributed to a male gamete dysfunction. The adoption of assisted fertilization techniques particularly ICSI has been able to alleviate male factor infertility by granting the consistent ability of a viable spermatozoon to activate an oocyte. Single sperm injection, by pinpointing the beginning of fertilization, has been an invaluable tool in clarifying the different aspects of early fertilization and syngamy. However, even with ICSI some couples fail to fertilize due to ooplasmic dysmaturity in relation to the achieved nuclear maturation marked by the extrusion of the first polar body. More uncommon are cases where the spermatozoa partially or completely lack the specific oocyte activating factor. In this work, we review the most relevant aspects of fertilization and its failure through assisted reproductive technologies. Attempts at diagnosing and treating clinical fertilization failure are described. 相似文献
105.
This paper describes three new Ortheziola species of the Palaearctic and Oriental regions. The specimens were extracted from forest litter using Berlese funnels, and are from the collections of Muséum d’Histoire naturelle de Genève, Switzerland. Thus the genus Ortheziola
sensu stricto now includes 12 species. An identification key, distribution map and new locality records for the Ortheziola species currently known are provided. 相似文献
106.
Durkan R Gürbüz A Yilmaz B Ozel MB Bagis B 《Journal of applied biomaterials & functional materials》2012,10(1):e37-e42
Introduction: Microwave and water bath postpolymerization have been suggested as methods to improve the mechanical properties of heat and autopolymerizing acrylic resins. However, the effects of autoclave heating on the fracture properties of autopolymerizing acrylic resins have not been investigated. Purpose: The aim of this study was to assess the effectiveness of various autoclave postpolymerization methods on the fracture properties of 3 different autopolymerizing acrylic resins. Methods: Forty-two specimens of 3 different autopolymerizing acrylic resins (Orthocryl, Paladent RR and Futurajet) were fabricated (40x8x4mm), and each group was further divided into 6 subgroups (n=7). Control group specimens remained as processed (Group 1). The first test group was postpolymerized in a cassette autoclave at 135°C for 6 minutes and the other groups were postpolymerized in a conventional autoclave at 130°C using different time settings (5, 10, 20 or 30 minutes). Fracture toughness was then measured with a three-point bending test. Data were analyzed by ANOVA followed by the Duncan test (α=0.05). Results: The fracture toughness of Orthocryl and Paladent-RR acrylic resins significantly increased following conventional autoclave postpolymerization at 130°C for 10 minutes (P<.05). However, the fracture toughness of autoclave postpolymerized Futurajet was not significantly different than its control specimens (P<.05). The fracture toughness of Futurajet was significantly less than Paladent RR and Orthocryl specimens when autoclaved at 130°C for 10 minutes. Conclusions: Within the limitations of this study, it can be suggested that autoclave postpolymerization is an effective method for increasing the fracture toughness of tested autoploymerized acrylic resins. 相似文献
107.
Age-related macular degeneration (AMD) is a leading cause of central blindness in the elderly population. The wet type of AMD is characterized by extensive growth of new vessels. One of the effective strategies to treat wet AMD is to limit the choroidal neovascularization (CNV). We studied the effects of adiponectin peptide I (APNpI) on new vessel growth in laser-induced rat model of wet AMD and on rat choroidal endothelial cell (CEC) culture. CNV size and vessel density were investigated by microscopy. Immunohistochemical staining (IHC) for von Willebrand Factor (vWF), APN, APN receptors 1 (AdipoR1), 2 (AdipoR2), VEGF, VEGF receptor 2 (VEGF-R2), proliferating cell nuclear antigen (PCNA) was performed in CNV area. The mRNA expression of VEGF and VEGF-R2 in RPE-choroid was investigated by RT-PCR and real-time PCR. APNpI inhibited area of CNV by 4 fold, number of vWF positive vessels by 99% and area of subretinal tissue by 40%. The expression of VEGF and VEGF-R2 at mRNA and protein levels decreased after APNpI treatment in vivo. Proliferative index (PCNA) was 5 folds less in laser spots of APNpI treated rats compared to controls. In conclusion, APNpI inhibited formation of new vessels in rat model of CNV by decreasing VEGF, VEGF-R2 expression and cell proliferation. Thus, APNpI may have potential therapeutic use for AMD treatment since it significantly inhibited CNV. 相似文献
108.
Fifty fluorescent pseudomonads were isolated from rhizospheric soil of green gram from nearby area of Kaziranga, Assam, India
and assayed for their extracellular proteinase production. Out of these isolates, 20 were found to be prominent in proteinase
production. Genetic diversity of the 20 isolates were analyzed through BOX-PCR fingerprinting and 16S rDNA-RFLP along with
three reference strains, viz., Pseudomonas fluorescens (NCIM2099T), Pseudomonas aureofaciens (NCIM2026T), and Pseudomonas aeruginosa (MTCC2582T). BOX-PCR produced two distinct clusters at 56% similarity coefficient and seven distinct BOX profiles. 16S rDNA-RFLP with
three tetra-cutters restriction enzymes (HaeIII, AluI, and MspI) revealed two major clusters A and B; cluster A contained only single isolate FPS9 while the rest of 22 isolates belonged
to the cluster B. Based on phenotypic characters and 16S rDNA sequence similarity, all the eight highly proteinase-producing
strains were affiliated with P. aeruginosa. The proteinase was extracted from two most prominent strains (KFP1 and KFP2), purified by a three-step process involving
(NH4)2SO4 precipitation, gel filtration, and ion exchange chromatography. The enzyme had an optimal pH of 8.0 and exhibit highest activity
at 60°C and 37°C by KFP1 and KFP2 respectively. The specific activities were recorded as 75,050 (for KFP1) and 81,320 U/mg
(for KFP2). The purified enzyme was migrated as a single band on native and SDS-PAGE with a molecular mass of 32 kDa. Zn2+, Cu2+, and Ni2+ ion inhibited the enzyme activity. Enzyme activity was also inhibited by EDTA established as their metallo-proteinase nature. 相似文献
109.
Prabhu M Siva Sankar MS Bhanuprakash V Venkatesan G Bora DP Yogisharadhya R Balamurugan V 《Biologicals》2012,40(1):92-95
In the present study, SYBR Green and TaqMan real time PCRs (rt-PCR) based on the C18L gene (encodes ankyrin repeat protein) of camelpox (CMLV) and buffalopox viruses (BPXV) were, respectively employed for potency evaluation of live attenuated camelpox and buffalopox vaccines. Cells infected with the respective vaccine viruses were harvested at critical time points and subjected to respective PCRs. The critical time points of harvests for CMLV and BPXV respectively, were 36 and 30 h post infection and were respectively determined based on maximum slopes of (−3.324) and (−3.321) standard curves. On evaluation of eight batches of camelpox and seven batches of buffalopox vaccines, the results indicated that the titres estimated by respective rt-PCRs were well comparable to the conventional TCID50 method. The rt-PCR assays were found relatively more sensitive, specific and rapid than end point dilution assay. Thus, they could be used as additional tools for estimation of live CMLV and BPXV particles in camelpox and buffalopox vaccines. 相似文献
110.
Photoreactive cellulose membrane--A novel matrix for covalent immobilization of biomolecules 总被引:2,自引:0,他引:2
We report a simple and mild procedure for the preparation of a photoreactive cellulose membrane capable of forming a covalent bond with a biomolecule in presence of 365 nm UV light. Photoreactive cellulose membrane was prepared by the reaction of fluoro group of 1-fluoro-2-nitro-4-azidobenzene (FNAB) and hydroxyl group of the cellulose in an alkaline medium. X-ray photoelectron spectroscopy (XPS) of the photoreactive cellulose confirmed the incorporation of FNAB moiety. Azido group of the photoreactive membrane on exposure to UV light transforms into highly reactive nitrene which binds with a protein. The efficacy of the activated membrane was checked by immobilizing glucose oxidase (GOD) onto it in presence of light. Immobilized GOD was found to have improved thermal, pH and storage stability. Photoreactive cellulose membrane was successfully used in enzyme-linked immunosorbent assay (ELISA) technique. The antibody immobilized onto such support by UV irradiation in 30 min showed similar ELISA value than the antibody immobilized onto a polystyrene ELISA plate in 12h incubation at 4 degrees C by conventional method. 相似文献