RESUMEN
The primary male-goats Lac-1 (human lactoferrin gene construct hLF5) and Lac-2 (human lactoferrin gene construct hLF3) with genome containing human lactoferrin gene were bred and the sperm bank of primary male-goats and their male descendents (F1-F7) was created. The herd of goats (200 transgenic females) that produced recombinant human lactoferrin (rhLF) in their milk at levels up to 16 g/L was obtained. The rhLF from milk of transgenic goats, natural human lactoferrin (hLF) from woman milk and natural goat lactoferrin (gLF) from milk of non-transgenic goats were purified using cation-exchange chromatography. It has been shown that rhLF is a glycoprotein and its physicochemical characteristics of rhLF are similar to hLf as revealed by different analytical methods including electron paramagnetic resonance, spectrophotometry, differential scanning calorimetry, mass spectrometry and peptide mapping. The high expression level of rhLF achieved in milk of transgenic goats provides a solid basis for developing an efficient and cost-effective downstream processing. The rhLF exhibited a prominent biological activity suggesting it as a promising biopharmaceutical and food supplements.
Asunto(s)
Animales Modificados Genéticamente/genética , Lactoferrina/genética , Proteínas Recombinantes/genética , Animales , Productos Lácteos , Femenino , Regulación de la Expresión Génica/genética , Glicosilación , Cabras/genética , Humanos , Lactoferrina/biosíntesis , Masculino , Leche/metabolismo , Proteínas Recombinantes/biosíntesisRESUMEN
We have performed experiments using magnetocumulative generators (MCGs) to power three different types of high-energy-density plasma discharges suitable for intense x-ray generation. They include the H-pressed discharge, the capillary z-pinch, and the θ-pinch. The MCGs were operated with, and without, plasma opening switches. The characteristic currents were approximately 10 MA and characteristic time scales approximately 1 µs. In this paper we describe the characteristics of these experiments.
RESUMEN
The results of experiments with a plasma x-ray source in the PIRIT-2000 facility are presented in this paper. The facility is designed with module capacitive energy storage energizing vacuum inductive storage. The formation of a rapidly growing current pulse as well as its commutation on a load was carried out by a plasma opening switch. A vacuum diode as well as various types of plasma loads can be used for the generation of a high-power x-ray flux. The storage energy of a 54-module capacitive storage is up to 2 MJ, its inductance is 15 nH, and its output voltage is 500 kV. The peak current in the plasma load constituted 4 MA with a 150-ns rise time. The maximum integral energy output of x radiation measured by an open thermocouple calorimeter was as high as 100 kJ, while the primary storage energy was 1 MJ. The plasma load usage at a current of 4 MA ensured a 100-kJ generation in x-ray radiation and the density of the radiation flux at a distance of 1 m from the source was as much as 0.8 J/cm2, while near the source it was 10 J/cm2.
RESUMEN
This paper gives the results of studies on a plasma x-ray source, which enables one to obtain a 2.5-krad radiation dose per pulse over an area of 100 cm2 in the quantum energy range from 20 to 500 keV. Pulse duration is 100 ns. Spectral radiation distributions from a diode under various operation conditions of a plasma are obtained. A Marx generator served as an initial energy source of 120 kJ with a discharge time of T/4 = 10-6 s. A short electromagnetic pulse (10-7 s) was shaped using plasma erosion opening switches.