High dispersion CCD spectra are used to study the profiles of the Ha and Hb lines of 48 stars in early spectral classes in the young diffuse binary cluster h/j Per. In addition, moderate resolution ...spectra of 15 B and Be stars were taken over the interval 4400-4960 . One or, possibly, two new Be stars are discovered. The major parameters of the Ha line are measured for the observed B and Be stars. The spectra over 4400-4960 are used to estimate T(eff), logg, and usin i. No traces of emission are detected in the Ha line profiles for 28 of the stars and emission is observed in the Ha line for 20. During our observations an absorption profile of the Ha line was observed for some of the stars, such as Oo146, Oo566, Oo922, and Oo1268, although they have previously been identified as Be stars. A significant long-term variability of the Ha line is discovered for the Be stars Oo1161 and Oo2242. Oo2371 manifests a variability in its faint emission spectrum which is typical of close binary systems that include a Be star.
Early sea urchin embryos are sensitive to agonists and antagonists of transmitter receptors, both metabotropic and channel ones. In this work, we studied mechanisms of the cytostatic action of ...cyproheptadine and haloperidol–antagonists of serotonin 5HT
2
receptors and dopamine D
2
receptors, respectively. For this purpose, we employed the model of the blockade of the first cleavage division in sea urchin, which allows quantifying the effects of embryotoxic substances. The action of haloperidol and cyproheptadine is mediated by the effects on cytoskeleton elements. Both antagonists caused an increase in the degree of polymerization of the actin cytoskeleton, both in the cortical layer and in the cytoplasm. In addition, both antagonists affected the tubulin cytoskeleton: haloperidol predominantly disturbed spatial organization of the mitotic spindle, while cyproheptadine caused a complete depolymerization of tubulin and arrest of mitotic processes. The results indicate that cytostatic effects of dopamine and serotonin antagonists on cleavage divisions of sea urchin embryos are mediated by similar and/or crosstalk molecular mechanisms but also have significant differences that require further research.
To clarify the organizing effect of Semax and HLDF-6 peptides on the kinetics of protein synthesis in hepatocytes, in addition to an in vitro study (Brodsky et al., 2019), the effects of these ...peptides in vivo have been studied. The circahoralian (ultradian) rhythm of protein synthesis, that is, a marker of the direct cell-to-cell communication, was investigated in rats of different ages. Peptides were injected intraperitoneally into young (2–3-month-old) or old (1.5–2-year-old) rats at a 50–100-µg/kg dose. Hepatocytes were isolated and sparse or dense cultures were established. In sparse cultures from young rats that received one or another peptide, the rhythm of protein synthesis was observed; in the cultures from rats of the same age that were injected with saline, no rhythm was found. In dense cultures of old rats after the action of the peptide, the amplitudes of the rhythm of protein synthesis did not differ from the rhythms observed in young rats; after saline injection, the rhythm amplitudes were twice as low. Injection of the peptide into adult rats that had previously received dopamine caused a protein synthesis rhythm characteristic for rats of this age; the administration of dopamine abolished the rhythm. The synchronizing effect of the peptides was maintained for at least 2 days after their single administration to the rat. The use of Semax or HLDF-6 is recommended to compensate for the disturbances of the kinetics of protein synthesis in humans in aging and pathology.
In the search for stable factors regulating direct cell–cell interactions and effects on the properties of cells in aging organisms, the regulatory peptides Semax and HLDF-6 were studied. The ...circahoralian rhythm of protein synthesis in cells in vitro served as a marker of cell–cell interactions. The peptides normalized the cell–cell interactions, which are greatly weakened during aging. It is shown that the peptides organize the protein-synthesis rhythm in primary rat hepatocyte cultures. The effect of the HLDF-6 peptide was realized via metabotropic glutamate receptors; the blockade of these receptors by the antagonist MCPG abolished the effect of the peptide. The protein kinase inhibitor H7 prevented the effect of the peptides on the protein-synthesis kinetics. Just as for other signaling factors, the activation of protein kinases in the case of the peptides regulates the key process of direct cell–cell interactions. The effect of a single signal of each of the peptides was retained for at least 1 day. Our data allow the peptides to be recommended for improving elderly people’s condition and block the factors that disorganize the protein-synthesis kinetics.
On high-resolution spectra, obtained in the Hα region and medium resolution spectra obtained in the region 4420-4960A together with radial velocities, which was taken from other published sources we ...analyzed the radial velocities and calculate orbital parameters of the massive binary system V622 Per. It is shown that the system has an orbital period 5.2 days and is a post mass transfer binary. Temperature of components and an inclination angle of the system were obtained from light curve analysis of the ellipsoidal variability. Luminosity ration of components was found of about 4:1. Teff and log g for each of components was estimated. It is shown that primary, less massive but brighter star is an evolved object that has lost a large part of the mass during its evolution. Estimations of the primary chemical composition showed a noticeable enrichment of products of the CNO cycles such as He/H reach 0.18, the nitrogen is in excess of about 0.5 dex, the carbon has lower abundances (by 2-3 dex lower) and the oxygen has 1 dex lower than solar abundance. The possible evolution of the binary with the known age 17 Myear is discussed.
Radial velocities analysis based on high-resolution spectra, obtained in the H\(\alpha\) region and low resolution spectra obtained in the region 4420-4960\AA together with radial velocities, taken ...from other published sources allow us to calculate orbital parameters of the massive binary system V622 Per. It is shown that the system has an orbital period 5.214(29) days, T\(_0\) = 2450661(4) and is a post mass transfer binary. From light curve analysis of the ellipsoidal variability we obtained inclination angle of the system and temperature of the components. Luminosity ration of the components was found of about 4:1. T\(_{eff}\) and \(log g\) were estimated for each component. It is shown that primary, less massive but more bright star, is an evolved object that has lost large part of its mass during the evolution. Estimations of chemical composition of the primary show noticeable enrichment by products of the CNO cycles. E.g. He/H reaches 0.18, nitrogen is in excess of about 0.5 dex, carbon has low abundances (by 2-3 dex lower) and oxygen has 1 dex lower than solar abundance. The possible evolution of the binary with the known age 14 Myrs is discussed.
Melatonin administered to rat intraperitoneally organizes ultradian rhythm of protein synthesis in hepatocytes that persists for 1 day after exposure to the synchronizing signal. Hepatocytes were ...isolated 1 day after melatonin administration and cultured on coverslips in a serum-free medium. In 24 h in culture, the kinetics of protein synthesis was analyzed. In our previous experiments, we detected a rhythm in cells isolated in 1.5 h, but not in 3 days after melatonin administration to the rat. We have found that synchronization of oscillations of the protein synthesis intensity
in vivo
persists over 1 day after rat exposure to melatonin. Phenylephrine, an efficient synchronizer of protein synthesis
in vitro
, does not organize the rhythm
in vivo
.
Chondrosarcomas are malignant cartilage tumors that do not respond to traditional chemotherapy or radiation. The 5-year survival rate of histologic grade III chondrosarcoma is less than 30%. An ...animal model of chondrosarcoma has been established--namely, the Swarm Rat Chondrosarcoma (SRC)--and shown to resemble the human disease. Previous studies with this model revealed that tumor microenvironment could significantly influence chondrosarcoma malignancy.
To examine the effect of the microenvironment, SRC tumors were initiated at different transplantation sites. Pyrosequencing assays were utilized to assess the DNA methylation of the tumors, and SAGE libraries were constructed and sequenced to determine the gene expression profiles of the tumors. Based on the gene expression analysis, subsequent functional assays were designed to determine the relevancy of the specific genes in the development and progression of the SRC.
The site of transplantation had a significant impact on the epigenetic and gene expression profiles of SRC tumors. Our analyses revealed that SRC tumors were hypomethylated compared to control tissue, and that tumors at each transplantation site had a unique expression profile. Subsequent functional analysis of differentially expressed genes, albeit preliminary, provided some insight into the role that thymosin-β4, c-fos, and CTGF may play in chondrosarcoma development and progression.
This report describes the first global molecular characterization of the SRC model, and it demonstrates that the tumor microenvironment can induce epigenetic alterations and changes in gene expression in the SRC tumors. We documented changes in gene expression that accompany changes in tumor phenotype, and these gene expression changes provide insight into the pathways that may play a role in the development and progression of chondrosarcoma. Furthermore, specific functional analysis indicates that thymosin-β4 may have a role in chondrosarcoma metastasis.
Primary cultures of rat hepatocytes were studied in serum-free medium. Ultradian protein synthesis rhythm was used as a marker of overall cell synchronization and cooperation amongst the population. ...The level of synchronization was determined by amplitudes of the rhythm. Low synchronization of old rat hepatocytes can be enhanced by addition of either gangliosides or phenylephrine to the medium. Incubation of cultures with gangliosides lasted for 2.5
h, while action of phenylephrine was only for 2
min. The amplitude of protein synthesis rhythm was increased 1.5–2 times. In cultures transferred to a fresh normal medium, this increased amplitude was observed for at least 2–3 days. Thus, both gangliosides and phenyleprine are triggers, which, as shown earlier, initiated calcium-dependent processes in the cytoplasm. The results are discussed in the light of concept of the cell self-organization by a direct cell–cell communication.
Chondrosarcomas are among the most malignant skeletal tumors. Dedifferentiated chondrosarcoma is a highly aggressive subtype of chondrosarcoma, with lung metastases developing within a few months of ...diagnosis in 90% of patients. In this paper we performed comparative analyses of the transcriptomes of five individual metastatic lung lesions that were surgically resected from a patient with dedifferentiated chondrosarcoma. We document for the first time a high heterogeneity of gene expression profiles among the individual lung metastases. Moreover, we reveal a signature of “multifunctional” genes that are expressed in all metastatic lung lesions. Also, for the first time, we document the occurrence of massive macrophage infiltration in dedifferentiated chondrosarcoma lung metastases.
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