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251.
Deformities/anomalies in fish body shapes have important implications on the marketability of the fish and thus can affect particularly the consumer perception of aquaculture-produced fish, raising concerns on animal welfare. The aim of this study was to detect the distribution of deformities in cultivated Sparus aurata that were raised to market size and sold in Istanbul Gürpınar Wholesale Fish Market in 2017–2018. We used external examination methods and X-ray imaging techniques to detect body deformities. Various types of deformities were found such as lordosis, cranial malformations, malpigmentation and change in the number of vertebrae. In most cases the same fish exhibited several malformations.  相似文献   
252.
Sensitive detection of protein aggregates is important for evaluating the quality of biopharmaceuticals and detecting misfolded proteins in several neurodegenerative diseases. However, it is challenging to detect extremely low concentrations (<10 ppm) of aggregated protein in the presence of high concentrations of soluble protein. Glucagon, a peptide hormone used in the treatment of extreme hypoglycemia, is aggregation-prone and forms amyloid fibrils. Detection of glucagon fibrils using conformation-specific antibodies is an attractive approach for identifying such aggregates during process and formulation development. Therefore, we have used yeast surface display and magnetic-activated cell sorting to sort single-chain antibody libraries to identify antibody variants with high conformational specificity for glucagon fibrils. Notably, we find several high-affinity antibodies that display excellent selectivity for glucagon fibrils, and we have integrated these antibodies into a sensitive immunoassay. Surprisingly, the sensitivity of our assay—which involves direct (nonantibody mediated) glucagon immobilization in microtiter plates—can be significantly enhanced by pretreating the microtiter plates with various types of globular proteins before glucagon immobilization. Moreover, increased total concentrations of glucagon peptide also significantly improve the sensitivity of our assay, which appears to be due to the strong seeding activity of immobilized fibrils at high glucagon concentrations. Our final assay is highly sensitive (fibril detection limit of ~0.5–1 ppm) and is >20 times more sensitive than detection using a conventional, amyloid-specific fluorescent dye (Thioflavin T). We expect that this type of sensitive immunoassay can be readily integrated into the drug development process to improve the generation of safe and potent peptide therapeutics.  相似文献   
253.
Successful nanobiotechnology implementation largely depends on control over the interfaces between inorganic materials and biological molecules. Controlling the orientations of biomolecules and their spatial arrangements on the surface may transform many technologies including sensors, to energy. Here, we demonstrate the self-organization of L -lactate dehydrogenase (LDH), which exhibits enhanced enzymatic activity and stability on a variety of gold surfaces ranging from nanoparticles to electrodes, by incorporating a gold-binding peptide tag (AuBP2) as the fusion partner for Bacillus stearothermophilus LDH (bsLDH). Binding kinetics and enzymatic assays verified orientation control of the enzyme on the gold surface through the genetically incorporated peptide tag. Finally, redox catalysis efficiency of the immobilized enzyme was detected using cyclic voltammetry analysis in enzyme-based biosensors for lactate detection as well as in biofuel cell energy systems as the anodic counterpart. Our results demonstrate that the LDH enzyme can be self-immobilized onto different gold substrates using the short peptide tag under a biologically friendly environment. Depending on the desired inorganic surface, the proposed peptide-mediated path could be extended to any surface to achieve single-step oriented enzyme immobilization for a wide range of applications.  相似文献   
254.
Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) is one of the most important and effective predators of Tetranychus spp. (Acari: Tetranychidae). This study analyzed the effects of hexythiazox and spiromesifen resistance on biological characteristics of N. californicus. Pre-oviposition, oviposition, post-oviposition times, adult lifespan, total number of eggs laid per female, net reproductive rate (R0), intrinsic rate of increase (rm), doubling time (DT), mean generation time (T) and finite rate of increase (λ) were compared among three populations: 63.9-fold hexythiazox resistant (HEX14), 53.6-fold spiromesifen resistant (SPR13) and a susceptible base population. Pre-oviposition and oviposition times, mean number of eggs/female, adult lifespan, R0 and rm values were all significantly higher for the two resistant populations than for the susceptible population. Life tables of HEX14, SPR13 and the susceptible population showed that R0 was 35.0, 26.5 and 19.4 (females/female generation), rm was 0.35, 0.32 and 0.30 (females/female/day), DT was 1.92, 2.07 and 2.27 days, T was 9.8, 9.8 and 9.7 days, and λ was 1.43, 1.39 and 1.35 (individuals/female/day), respectively.  相似文献   
255.
Drugs known to inhibit phenylethanolamine-N-methyltransferase (EC 2.1.1.28), the final enzyme in the epinephrine synthetic pathway were administered to rats and their effects on pituitary-arenal function studied. 2, 3-Dichloro-α-methylbenzylamine (DCMB) produced dose-related increases in plasma corticosterone in basal and stressed rats. Evidence for the central nature of this tonic inhibitory effect of epinephrine was its continued presence in adrenal demedullated rats. 2-chloro-3-trifluoromethyl-α-benzylamine (CTFMB) administration elevated plasma corticosterone and this effect was highly correlated to the decrease in hypothalamic epinephrine concentration in both sham operated and adrenal demedullated rats. These findings argue for tonic epinergic inhibition of pituitary-adrenal function.  相似文献   
256.
257.
Molecular Biology Reports - Diabetic chronic wound, which is one of the diabetic complications caused by hyperglycemia, characterized by prolonged inflammation has become one of the most serious...  相似文献   
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