Investigation of the content of alpha-fetoprotein and serum albumin in the vitreous body of the eye of human embryos

The content of serum albumin and alpha-fetoprotein in the vitreous body of the eyes of human fetuses from the 16th through the 24th week was investigated. It was detected that albumin and alpha-fetoprotein in the vitreous body of human eyes are presented in equal molar concentrations in the 16th week. There is 1.5-fold increased concentration of alpha-fetoprotein in comparison to albumin during the 17th week. After the 17th week, there was a reduction in the concentration of both proteins. It was reported that cyanine dye, used for detection of albumin, does not interact with alpha-fetoprotein.     

Dependence of fluorescence spectra of chloroplasts from the activity of photosystem 2]

By means of high sensitive spectrofluorometer the fluorescence spectra have been measured of normal chloroplasts and those with blocked photosystem 2 activity due to photoinhibition or treatment with 0.6 M tris-buffer. At room temperature fluorescence spectra of inactivated chloroplasts are similar to the spectrum of normal chloroplasts measured at low light intensity. Under excitation by intense light a decrease of intensity at 685 nm is appeared (about 3-4 times) in the fluorescence spectra of inactivated chloroplasts as compared to the spectrum of normal chloroplasts. The sharp intensity decrease of maxima at 685 and 695 nm (3-4 times) and small decrease at 680 and 730 nm (by 30-50%) are observed in low temperature fluorescence spectra of inactivated chloroplasts. Thus, the damage of photosystem 2 reaction centres is not accompanied by the preferential decrease of the only fluorescence band. The similarity of fluorescence difference spectra of chloroplasts distinguished by the state of photosystem 2 reaction centre, and the complex structure of difference spectra indicate that the variable fluorescence of chloroplasts during the induction is due to the emission of bulk chlorophyll alpha of the photosystem 2.     

Enhanced-contrast two-photon optogenetic pH sensing and pH-resolved brain imaging

We present experiments on cell cultures and brain slices that demonstrate two-photon optogenetic pH sensing and pH-resolved brain imaging using a laser driver whose spectrum is carefully tailored to provide the maximum contrast of a ratiometric two-photon fluorescence readout from a high-brightness genetically encoded yellow-fluorescent-protein-based sensor, SypHer3s. Two spectrally isolated components of this laser field are set to induce two-photon-excited fluorescence (2PEF) by driving SypHer3s through one of two excitation pathways—via either the protonated or deprotonated states of its chromophore. With the spectrum of the laser field accurately adjusted for a maximum contrast of these two 2PEF signals, the ratio of their intensities is shown to provide a remarkably broad dynamic range for pH measurements, enabling high-contrast optogenetic deep-brain pH sensing and pH-resolved 2PEF imaging within a vast class of biological systems, ranging from cell cultures to the living brain.     

The role of a local infectious focus in the development of Pseudomonas aeruginosa sepsis (experimental research)

The dynamics of sepsis development and the formation of metastatic foci have been studied using an experimental model. It has been established, that at the initial stages, the process manifests itself by bacteremia and endotoxemic shock, as well as by the complex of vascular disorders. The dependence of the formation of metastatic abscesses on the terms of the primary focus excision as well as the irreversibility of sepsis at the definite stage of infectious process have been studied. It is supposed, that the primary focus initiates the cascade activation mechanism of the factors, that determine the transition of bacteremia to the stage of septicopyemia.     

Protein mass in human cardiomyocytes does not correspond to gene content

Lack of proportionality between DNA and protein content has been revealed in the human cardiac myocytes. The proportion 2:4:8:16 was observed in DNA of di-, tetra-, octa- and hexadeca myocytes while the protein content of the same cells was 2:3.5:5.2:7.2 in the inner layer, 2:3.5:6.5:8.9 in the central layer and 2:3.1:5.6:9.1 in the outer layer of the normal left ventricle. The protein content of myocytes of the same ploidy was higher in the inner layer than in other ones.