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71.
Marleen Julia Meyer Simon Falk Sarah Rmer Clarissa Prinzinger Sabine Tacke Joachim Geyer Stefan Simm Mladen Vassilev Tzvetkov 《International journal of molecular sciences》2022,23(9)
OCT1 and OCT2 are polyspecific membrane transporters that are involved in hepatic and renal drug clearance in humans and mice. In this study, we cloned dog OCT1 and OCT2 and compared their function to the human and mouse orthologs. We used liver and kidney RNA to clone dog OCT1 and OCT2. The cloned and the publicly available RNA-Seq sequences differed from the annotated exon-intron structure of OCT1 in the dog genome CanFam3.1. An additional exon between exons 2 and 3 was identified and confirmed by sequencing in six additional dog breeds. Next, dog OCT1 and OCT2 were stably overexpressed in HEK293 cells and the transport kinetics of five drugs were analyzed. We observed strong differences in the transport kinetics between dog and human orthologs. Dog OCT1 transported fenoterol with 12.9-fold higher capacity but 14.3-fold lower affinity (higher KM) than human OCT1. Human OCT1 transported ipratropium with 5.2-fold higher capacity but 8.4-fold lower affinity than dog OCT1. Compared to human OCT2, dog OCT2 showed 10-fold lower transport of fenoterol and butylscopolamine. In conclusion, the functional characterization of dog OCT1 and OCT2 reported here may have implications when using dogs as pre-clinical models as well as for drug therapy in dogs. 相似文献
72.
ABSTRACTWind turbine control is an important task to make the electricity generation secure in terms of energy demand and machine safety. It also yields to control the desired power level and optimized energy because of the assignment of turbine speed. The contactless piezoelectric wind energy harvester (CPWEH) used in this study has three piezoelectric layers located around the shaft with 120 degrees apart and they are buckled by the magnetic force without any physical contact. The superiority of this device is to generate energy for low wind speeds such as 1.5 m/s. However, for high speeds, high total harmonic distortions (THDs) govern the waveforms, thus controlling the turbine speed becomes necessary for optimizing the output power. Encouraged by this, a small low inertia dc generator is coupled with the wind turbine, and the generator terminals are connected to a resistor through a power switch to generate a braking torque that opposes to wind speed direction. By controlling the switch properly, turbine speed is ensured to remain within a certain band, which accordingly prevents the turbine from rotating very fast at damaging wind speeds. Several experiments are performed on the developed CPWEH with/without the presented control scheme which prove the existence of promising performance of our proposal. 相似文献
73.
Prof. Dr. Özkan Özden Dr. Şafak Ulusoy Assoc. Prof. Dr. Nuray Erkan 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,5(3-4):407-412
Sea food is a major source of animal protein. Marine foods are very rich sources of mineral components. The total content of minerals in the raw flesh of marine fish and invertebrates is in the range of 0.6–1.5% wet weight. The contents of Na, K, Ca, Mg and P are up to 1 mg/100 g, whereas those of Fe, Zn, I are less than 1 mg/100 g. Mussels (Mytilus galloprovincialis) were investigated for macro and trace element composition throughout the year. Ranges of moisture, ash, protein and fat contents were 79.76–87.46 g/100 g, 1.06–2.06 g/100 g, 7.28–12.65 g/100 g and 0.33–3.49 g/100 g, respectively. While the highest protein and fat values were found in the summer (July–August), the highest moisture and ash contents were found in the winter (December–January). The contents of highest Na, K, Ca were found in the summer. Cadmium, lead and copper were found to be below the legislative limits throughout year. High levels of mercury were found in January and October. It should be discussed whether mussel may provide an alternative source of mineral for healthy nutrition. 相似文献
74.
This paper investigated the uniaxial mechanical properties of a new type of hollow sphere structures. For this new type, the sphere shell was perforated by several holes in order to open the inner sphere volume and surface. The mechanical properties, i.e. elastic properties and initial yield stress of perforated hollow sphere structures (PHSS) in a primitive cubic arrangement were numerically evaluated for different hole diameters and different joining techniques of the hollow spheres. The results are compa... 相似文献
75.
Swelling kinetics,mechanical properties,and release characteristics of chitosan‐based semi‐IPN hydrogels 下载免费PDF全文
Two series of pH‐sensitive semi‐interpenetrating network hydrogels (semi‐IPN) based on chitosan (CS) natural polymer and acrylamide (AAm) and/or N‐hydroxymethyl acrylamide (HMA) monomers by varying the monomer and CS ratios were synthesized by free radical chain polymerization. 5‐Fluorouracil (5‐FU), a model anticancer drug, has been added to the feed composition before the polymerization. The characterization of gels indicated that the drug is molecularly dispersed in the polymer matrix. The swelling kinetics of drug‐loaded gels have decreased with increased HMA content at 37°C in both distilled water and buffer solutions with a pH of 2.1 or 7.4. Elastic modulus of the gels increased with the increase in HMA content and higher CS concentration enhanced the elastic modulus positively. Moreover, cumulative release percentages of the gels for 5‐FU were ca. 10% higher in pH 2.1 than those in pH 7.4 media. It was determined that they can be suitable for the use in both gastric and colon environments. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41886. 相似文献
76.
A Comparative Study on Changes and Relationships of Kernel Biochemical Components in Different Types of Maize 下载免费PDF全文
Fatih Kahrıman Cem Ömer Egesel Başak Egesel 《Journal of the American Oil Chemists' Society》2015,92(10):1451-1459
A great deal of genetic variability and breeding efforts have yielded a number of specialty maize types. Little is known about how the off‐target traits in specialty maize kernel have changed and how they compare to those of standard maize genotypes. In this study, we compared the normal (NORMAL), high‐oil (HOM) and high‐protein maize (HPM) genotypes in terms of oil, protein, fatty acids and some mineral components. We also investigated the relationships among the evaluated traits in different kernel types. We detected a significant variation among the maize types for all of the investigated traits. Specialty maize genotypes had a superior performance for the traits they were specifically bred for, as well as kernel mineral content over the normal genotypes. HOM and HPM had similar values in terms of their fatty acid composition. However, they were different from the standard genotypes, with higher oleic and lower linolenic acid levels, which indicates that the specialty maize genotypes possess a better oil quality. Correlation analysis revealed that only three pairs of correlations out of 46 values had the same sign and a similar level of significance in different types. Such similarities or differences in correlation values for different types should be taken into account in the efforts for developing high quality maize genotypes. 相似文献
77.
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79.
The purpose of this study was to prepare hydrogels and microemulsion (ME)-based gel formulations containing 1% terbinafine hydrochloride (TER-HCL) and to evaluate the use of these formulations for the antifungal treatment of fungal infections. Three different hydrogel formulations were prepared using chitosan, Carbopol® 974 and Natrosol® 250 polymers. A pseudo-ternary phase diagram was constructed, and starting from ME formulation, a ME gel form containing 1% Carbopol 974 was prepared. We also examined the characteristic properties of the prepared hyrogels. The physical stability of hydrogels and the ME -based gels were evaluated after storage at different temperatures for a period of 3 months. The release of TER-HCL from the gels and the commercial product (Lamisil®) was carried out by using a standard dialysis membrane in phosphate buffer (pH 5.2) at 32?°C. The results of the in vitro release study showed that the Natrosol gel released the highest amount of drug, followed by Carbopol gel, chitosan gel, commercial product, and the microoemulsion-based gel in that order. In vitro examination of antifungal activity revealed that all the prepared and commercial products were effective against Candida parapsilosis, Penicillium, Aspergillus niger and Microsporum. These results indicate that the Natrosol®-based hydrogel is a good candidate for the topical delivery of TER-HCL. 相似文献
80.