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991.
Ghim SJ Rector A Delius H Sundberg JP Jenson AB Van Ranst M 《Biochemical and biophysical research communications》2004,324(3):1108-1115
Equus caballus papillomavirus type 1 (EcPV-1) was isolated from a cutaneous papilloma, the most common neoplasm in horses. The complete EcPV-1 nucleotide sequence and genomic organization were determined. Phylogenetic analysis showed that EcPV-1 is a close-to-root papillomavirus, with only distant relationships to the fibropapillomaviruses and the benign cutaneous papillomaviruses. To produce EcPV-1 virus-like particles (VLPs), the EcPV-1 L1 major capsid protein was expressed in insect cells using a recombinant baculovirus vector. The self-assembled EcPV-1 VLPs were morphologically indistinguishable from wild type papillomavirus virions. Monoclonal antibodies were developed against intact and denatured EcPV-1 VLPs. When tested by ELISA, all monoclonal antibodies produced against intact (#18) and some against denatured EcPV-1 VLPs (#16) reacted with intact EcPV-1 VLPs only, demonstrating that the VLPs carry type-specific conformational as well as linear epitopes on their surface. Recombinant EcPV-1 VLPs offer the potential of a noninfectious vaccine to prevent and eradicate equine cutaneous papillomatosis. 相似文献
992.
993.
Chronic infection with certain types of human papillomaviruses (HPV), especially HPV-16 and HPV-18, leads to the development of cervical cancer. Prophylactic HPV vaccines based on HPV virus like particles (VLPs) have now been developed. The commercial vaccines, Gardasil and Cervarix are clinically effective in preventing HPV infection but do not have a therapeutic effect against existing chronic HPV infections. However, papillomavirus (PV) VLPs elicit strong cytotoxic T cell (CTL) responses and PV VLPs without any adjuvant have therapeutic effects in animal PV infection model. Alum in Gardasil, Alum and 3-O-deacylated-4′-monophosphoryl lipid A (ASO4) in Cervarix may stimulate IL10 production and inhibit the Th1, CTL immune response of immunized individuals. PV VLPs also stimulate the production of IL10 by CD4+ T cells, which prevent their CTL generation effect as a therapeutic vaccine. Neutralizing IL10 at the time of PV VLPs immunization increases cytotoxic T cell responses. PV VLPs incorporating PV early protein E2, 6 and 7, together with immune stimulator that promote strong type 1 responses, and at the same time blocking the effect of IL10 may have therapeutic effect against HPV infection related diseases and are worth further basic and clinical investigation. 相似文献
994.
目的:探讨与观察面颈部吸脂结合脂肪移植在瘢痕整形中的临床应用效果。方法:采用回顾性研究方法,选择2017年8月到2020年6月在本院诊治的面颈部瘢痕患者78例作为研究对象,根据随机信封抽签原则把患者分为联合组与对照组各39例。对照组给予面颈部吸脂治疗,联合组给予面颈部吸脂结合脂肪移植治疗,治疗观察3个月。结果:联合组治疗后瘢痕部位的疼痛分级与对照组对比差异无统计学意义(P>0.05)。两组治疗后的美容权重评分与瘢痕基底深度都低于治疗前(P<0.05),联合组低于对照组(P<0.05)。治疗后联合组的总有效率为97.4%,高于对照组的82.1%(P<0.05)。联合组治疗期间的感染、栓塞、出血、神经损害等并发症发生率为5.1%,低于对照组的28.2%(P<0.05)。结论:面颈部吸脂结合脂肪移植在瘢痕整形中的临床应用并不会增加患者的疼痛,还能降低瘢痕基底深度与减少并发症的发生,提高患者的美容度与总体治疗效果。 相似文献
995.
为了比较不同锚钩蛋白基序结合活性,构建新型的鼠李糖乳杆菌颗粒表面展示系统。首先,用热酸处理法制备鼠李糖乳杆菌GEM(Gram-positive enhancer matrix,GEM)颗粒,并通过电镜观察、RT-PCR检测和SDS-PAGE检测鉴定其处理效果;同时,利用大肠杆菌表达了锚定蛋白PA3-EGFP和P60-EGFP并将其与GEM颗粒共同孵育结合;最后,使用免疫印迹、电镜观察、荧光显微镜观察和荧光分光光度法评价鼠李糖乳杆菌GEM颗粒与锚定蛋白的结合效率。结果表明,使用10%的TCA处理鼠李糖乳杆菌得到了灭活的肽聚糖骨架(GEM颗粒),经鉴定其大小形态均一,绝大部分无蛋白残留,3.8×10~6个GEM颗粒样品中的DNA拷贝数仅为32;免疫印迹和荧光显微镜观察均可检测到融合蛋白PA3-EGFP和P60-EGFP锚定在GEM颗粒上,且结合在GEM颗粒表面的锚定蛋白呈絮状。荧光分光光度计法检测结果显示锚定蛋白PA3-EGFP结合GEM的效率稍高于P60-EGFP,但差异不显著(P0.05)。以上结果表明由鼠李糖乳杆菌制得的GEM颗粒与锚定蛋白PA3、P60的结合效率良好,可用于构建新型的外源蛋白表面展示系统,进而为后续的细菌样颗粒疫苗的研究与应用奠定基础。 相似文献
996.
Summary The ultrastructure of the fat body of Aedes aegypti was followed from emergence through a blood meal. Changes in the volume of protein granules and lipid droplets were also examined. The relationship of these events to the known endocrinology of vitellogenin synthesis in mosquitoes is discussed.Massachusetts Experiment Station Paper No. 2130. Supported by the Massachusetts Agricultural Experiment Station, Project n° 356, and by NIH grant n° AI-11909 相似文献
997.
Karen Shapiro Colin Krusor Fernanda F. M. Mazzillo Patricia A. Conrad John L. Largier Jonna A. K. Mazet Mary W. Silver 《Proceedings. Biological sciences / The Royal Society》2014,281(1795)
Gelatinous polymers including extracellular polymeric substances (EPSs) are fundamental to biophysical processes in aquatic habitats, including mediating aggregation processes and functioning as the matrix of biofilms. Yet insight into the impact of these sticky molecules on the environmental transmission of pathogens in the ocean is limited. We used the zoonotic parasite Toxoplasma gondii as a model to evaluate polymer-mediated mechanisms that promote transmission of terrestrially derived pathogens to marine fauna and humans. We show that transparent exopolymer particles, a particulate form of EPS, enhance T. gondii association with marine aggregates, material consumed by organisms otherwise unable to access micrometre-sized particles. Adhesion to EPS biofilms on macroalgae also captures T. gondii from the water, enabling uptake of pathogens by invertebrates that feed on kelp surfaces. We demonstrate the acquisition, concentration and retention of T. gondii by kelp-grazing snails, which can transmit T. gondii to threatened California sea otters. Results highlight novel mechanisms whereby aquatic polymers facilitate incorporation of pathogens into food webs via association with particle aggregates and biofilms. Identifying the critical role of invisible polymers in transmission of pathogens in the ocean represents a fundamental advance in understanding and mitigating the health impacts of coastal habitat pollution with contaminated runoff. 相似文献
998.
M. Hetta Z. MussadiqA.-M. Gustavsson C. Swensson 《Animal Feed Science and Technology》2012,171(1):20-30
We evaluated effects of hybrid and advancing plant maturity on performance, chemical composition, and nutritional characteristics of whole plant forage maize as well as the relative contributions of its plant fractions at high latitudes. Three maize hybrids, Avenir (FAO 180), Isberi (FAO 190) and Burli (FAO 210), were grown in southern Sweden in a field experiment with a replicated complete randomized block design. Plants were harvested four times during maturation, and dry matter (DM) yield and DM as a proportion of fresh weight were recorded. Whole plants were separated into four morphological fractions representing stems, leaves, kernels and cobs and the contribution of each fraction to the DM of the whole plant was estimated. Plant material was subjected to chemical analysis followed by measurement of in vitro gas production (GP) in buffered rumen fluid and finally, by calculation of in vitro true digestibility of organic matter (OM) and neutral detergent fibre (aNDFom). The GP profiles were fitted to a first order kinetic model with a discrete lag. Parameters describing the GP profiles were used in a recently developed mechanistic two compartment rumen degradation model to estimate in vivo OM digestibility (OMD) and first order rate of degradation in the rumen. Hybrids were compared and effects of maturity were assessed by analysis of variance using DM concentration as covariate. There were differences (P<0.05) among the hybrids in DM yield and relative contributions of the plant fractions. Differences (P<0.05) in modelled in vivo digestibility of OM and rates of degradation also occurred among hybrids. Increased maturity caused a reduction in in vitro digestibility of aNDFom in all plant fractions (P<0.05), but increased the rate of rumen degradation of OM in the whole plant as evaluated from GP results. The DM yield had a quadratic relationship with increasing maturity, with maximum yield at a DM concentration of about 370 g/kg. In vitro GP can describe the nutritive characteristics of forage maize in relation to advancing maturity and increased maturity affected agronomic performance and plant composition as well as the nutritive characteristics of hybrids. 相似文献
999.
Fouad Sayah Antoinette Karlinsky Michel Breuzet 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1997,167(7):502-507
During the reproductive cycle of the female Labidura riparia, cytological observations show cyclical modifications of lipid droplets in the periovarian adipocyte. Fat body lipids and
their constitutive fatty acids are analyzed. The lipids are predominantly triacylglycerols, which increase after adult ecdysis
during vitellogenic and non-vitellogenic periods. Small amounts of diacylglycerols and phospholipids are found. Diacylglycerols
increase during vitellogenesis and decrease during the non-vitellogenic period. Cytological modifications of lipid droplets
are probably related to diacylglycerol fluctuations. Gas-liquid chromatography of fatty acid methyl esters shows oleic acid
to be the predominant fatty acid in total lipids and triacylglycerols; unsaturated acids are approximately twice as abundant
as saturated acids all along the reproductive cycle. Fatty acid composition of diacylglycerols and phospholipids differs from
triacylglycerols and total lipids composition. Palmitic, stearic, oleic and linoleic acids represent the major fatty acids;
their relative amounts vary during the different periods of the reproductive cycle. The correlations between fat body lipid
changes and ovarian development were discussed and compared with observations made on other insect species.
Accepted: 23 April 1997 相似文献
1000.
Parvin Babaei Arsalan Damirchi Rastegar Hoseini 《Journal of Exercise Nutrition & Biochemistry》2015,19(3):173-182