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31.
Fluorescence confocal microscopy was used to characterize micron-sized microfabricated silicon particles and planar oxide surfaces after silanization and immobilization of IgG antibody. Surfaces treated with amino- and mercaptosilanes were tested for the presence of amine and sulfhydryl groups by labeling with specific fluorescein probes. In addition, human antibody (IgG) was immobilized to the thiol-coated microparticles using the heterobifunctional crosslinker succinimidyl 4-(N-maleimidolmethyl)-cyclohexane-1-carboxylate. Estimates of the surface density of IgG were consistent with 8.3% of a monolayer of covalently-bound antibody. Confocal images confirmed uniform layers of both silanes and antibodies on the microparticles. The sensitivity limit for the confocal measurements was determined to be as low as 1.5 x 10(-5) fluors per nm2. 相似文献
32.
Fucosylated protein of retinal cone photoreceptor outer segments: morphological and biochemical analyses 下载免费PDF全文
Cone outer segments (OS) of the goldfish retina are diffusely labeled after intravitreal injection of [(3)H]fucose while rod OS remain unlabeled. By electron microscopic radioautography, the OS of red- and blue-sensitive cones are heavily labeled while green- sensitive cone OS are lightly labeled. The time-course and pattern of OS labeling in all cone types from 30 min to 24 h resemble that of incorporation of other sugars into rhodopsin in rod OS. The nature of the cone OS-specific fucosylated component(s) was examined using biochemical techniques. Cone OS were prelabeled by intravitreal injection of [(3)H]fucose 24 h before sacrifice. Photoreceptor OS were isolated using a discontinuous sucrose density gradient and it was verified by electron microscopic radioautography that the only source of radioactivity in the preparations was cone OS. The different cone types could be recognized by the heaviness of labeling, characteristic membrane spacing, and 'staining' of green cone OS in vitro with horseradish peroxidase. After acid hydrolysis of prelabeled photoreceptor membranes, 90 percent of the counts were in the neutral sugar fraction which was analyzed by thin-layer chromatography. Approximately 70 percent of the radioactivity co-chromatographed with authentic fucose. SDS-PAGE/fluorography of prelabeled photoreceptor membranes revealed a single radioactive component that was lightly stained with coomassie blue and showed an apparent molecular weight of 33,000. This cone-derived band was separated from unlabeled rod opsin which was well stained and showed an apparent mol wt of 38,000. Isoelectric focusing under denaturing conditions produced two major and one minor band of radioactivity with isoelectric points of 8.2, 8.6, and 8.8 respectively. No radioactivity was found in association with a stained band corresponding in isoelectric point to that of bovine opsin (pl, 6.2). The fucosylated component was readily digested by pronase, indicating its protein nature. Washing of the isolated OS with isotonic and hypotonic buffers failed to extract major amounts of the radioactivity, suggesting that the fucosylated component is an integral membrane protein. The presence of a fucosylated protein thus represents a major difference between cone and rod OS in the goldfish and has enabled us to identify cone OS in preparations of isolated photoreceptor membranes and to demonstrate the separation of a cone-derived glycoprotein from rod opsin. 相似文献
33.
Animal production systems convert plant protein into animal protein. Depending on animal species, ration and management, between 5% and 45 % of the nitrogen (N) in plant protein is converted to and deposited in animal protein. The other 55%-95% is excreted via urine and feces, and can be used as nutrient source for plant (= often animal feed) production. The estimated global amount of N voided by animals ranges between 80 and 130 Tg N per year, and is as large as or larger than the global annual N fertilizer consumption. Cattle (60%), sheep (12%) and pigs (6%) have the largest share in animal manure N production. The conversion of plant N into animal N is on average more efficient in poultry and pork production than in dairy production, which is higher than in beef and sheep production. However, differences within a type of animal production system can be as large as differences between types of animal production systems, due to large effects of the genetic potential of animals, animal feed and management. The management of animals and animal feed, together with the genetic potential of the animals, are key factors to a high efficiency of conversion of plant protein into animal protein. The efficiency of the conversion of N from animal manure, following application to land, into plant protein ranges between 0 and 60%, while the estimated global mean is about 15%. The other 40%-100% is lost to the wider environment via NH3 volatilization, denitrification, leaching and run-off in pastures or during storage and/or following application of the animal manure to land. On a global scale, only 40%-50% of the amount of N voided is collected in barns, stables and paddocks, and only half of this amount is recycled to crop land. The N losses from animal manure collected in barns, stables and paddocks depend on the animal manure management system. Relative large losses occur in confined animal feeding operations, as these often lack the land base to utilize the N from animal manure effectively. Losses will be relatively low when all manure are collected rapidly in water-tight and covered basins, and when they are subsequently applied to the land in proper amounts and at the proper time, and using the proper method (low-emission techniques). There is opportunity for improving the N conversion in animal production systems by improving the genetic production potential of the herd, the composition of the animal feed, and the management of the animal manure. Coupling of crop and animal production systems, at least at a regional scale, is one way to high N use efficiency in the whole system. Clustering of confined animal production systems with other intensive agricultural production systems on the basis of concepts from industrial ecology with manure processing is another possible way to improve N use efficiency. 相似文献
34.
35.
Elrasheid AH Kheirelseid Kah Hoong Chang John Newell Michael J Kerin Nicola Miller 《BMC molecular biology》2010,11(1):12
Background
Gene expression analysis has many applications in cancer diagnosis, prognosis and therapeutic care. Relative quantification is the most widely adopted approach whereby quantification of gene expression is normalised relative to an endogenously expressed control (EC) gene. Central to the reliable determination of gene expression is the choice of control gene. The purpose of this study was to evaluate a panel of candidate EC genes from which to identify the most stably expressed gene(s) to normalise RQ-PCR data derived from primary colorectal cancer tissue. 相似文献36.
The glucose transport system of the hyperthermophilic anaerobic bacterium Thermotoga neapolitana 下载免费PDF全文
The glucose transport system of the extremely thermophilic anaerobic bacterium Thermotoga neapolitana was studied with the nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DOG). T. neapolitana accumulated 2-DOG against a concentration gradient in an intracellular free sugar pool that was exchangeable with external source of energy, such as pyruvate, and was inhibited by arsenate and gramicidin D. There was no phosphoenolpyruvate-dependent phosphorylation of glucose, 2-DOG, or fructose by cell extracts or toluene-treated cells, indicating the absence of a phosphoenolpyruvate:sugar phosphotransferase system. These data indicate that D-glucose is taken up by T. neapolitana via an active transport system that is energized by an ion gradient generated by ATP, derived from substrate-level phosphorylation. 相似文献
37.
Serum from 88 pregnant sows and gilts was sampled 24 and 28 days after their first insemination or mating day. The oestrone sulphate (E1S) concentration in the samples was assessed with a commercially available radioimmunoassay kit modified for use with swine serum. The first aim was to test whether it was possible to predict litters of total number <10 piglets at term. The second aim was to compare the use of day 24 or day 28 samples, or of both, in this prediction. 相似文献
38.
Richard Harrop Franklin Chu Nashat Gabrail Sandy Srinivas Daniel Blount Anna Ferrari 《Cancer immunology, immunotherapy : CII》2013,62(9):1511-1520
The attenuated vaccinia virus, modified vaccinia Ankara, has been engineered to deliver the tumor antigen 5T4 (TroVax®). Here, we report results from a randomized open-label phase II trial in castration-resistant prostate cancer patients in which TroVax was administered in combination with docetaxel and compared against docetaxel alone. The aim was to recruit 80 patients (40 per arm), but the study was terminated early due to recruitment challenges. Therefore, this paper reports the comparative safety and immunological and clinical efficacy in 25 patients, 12 of whom were treated with TroVax plus docetaxel and 13 with docetaxel alone. 5T4-specific immune responses were monitored throughout the study. Clinical responses were assessed by measuring changes in tumor burden by CT and bone scan and by quantifying PSA concentrations. TroVax was well tolerated in all patients. Of 10 immunologically evaluable patients, 6 mounted 5T4-specific antibody responses. Patients treated with TroVax plus docetaxel showed a greater median progression-free survival of 9.67 months compared with 5.10 months for patients on the docetaxel alone arm (P = 0.097; HR = 0.31; 95 % CI 0.08–1.24). Importantly, a pre-treatment biomarker previously demonstrated to predict 5T4 immune response and treatment benefit showed a strong association with 5T4 antibody response and a statistically significant association with progression-free survival in patients treated with TroVax plus docetaxel, but not docetaxel alone. 相似文献
39.
Ashraf A Helmy Mostafa A Hamad Ahmed M Aly Tahra Sherif Mostafa Hashem Dalia AH El-Sers Mohammad Semieka 《Annals of surgical innovation and research》2011,5(1):1-9
Background
Biliary tract reconstruction continues to be a challenging surgical problem. Multiple experimental attempts have been reported to reconstruct biliary defects with different materials and variable outcome. Our aim was to evaluate a new method for biliary reconstruction using an isolated pedicled gastric tube in a live animal trial and also to present the first clinical case.Methods
Seven mongrel dogs underwent biliary reconstruction using gastric tube harvested, completely separated from the greater curvature, and based on a vascularized pedicle with the right gastroepiploic vessels. The tube was interposed between the common bile duct (CBD) and the duodenum. Postoperative mortality, morbidity, liver functions, gross and microscopic histological picture were assessed. The first clinical case was also presented where, in a patient with post-cholecystectomy biliary injury, an isolated pedicled gastric tube was interposed between the proximal and distal ends of the CBD.Results
One dog did not recover from anesthesia and another one died postoperatively from septic peritonitis. Five dogs survived the procedure and showed uneventful course and no cholestasis. The mean anastomotic circumference was 4.8 mm (range 4-6) for CBD anastomosis and 6.2 mm (range 5-7) for duodenal anastomosis. Histologically, anastomotic sites showed good evidence of healing. In the first clinical case, the patient showed clinical and biochemical improvement. Endoscopic retrograde cholangiography was feasible and assured patent biliary anastomoses.Conclusion
In mongrel dogs, biliary reconstruction using pedicled gastric tube interposition between CBD and duodenum is feasible with satisfactory clinical results, anastomotic circumference and histological evidence of healing. The technique is also feasible in human and seems to be promising. 相似文献40.
Jo Moore Stephen AC Hawkins Anthony R Austin Timm Konold Robert B Green Ian W Blamire Ian Dexter Michael J Stack Melanie J Chaplin Jan PM Langeveld Marion M Simmons Yvonne I Spencer Paul R Webb Michael Dawson Gerald AH Wells 《BMC research notes》2011,4(1):1-13