RESUMEN
We studied the effect of bovine brain gangliosides, individual ganglioside GM1, and melatonin on the rate of wound closure under in vitro conditions and the effect of melatonin on the rate of wound healing under in vivo conditions. It was shown that bovine brain gangliosides and melatonin reliably increased cell migration in the experimental wound model. This effect was detected when the cell cultures were treated with the test preparations after wound infliction and when the cultures of human keratinocytes were pretreated before wounding. Analysis of the effect of melatonin on the rate of wound healing in vivo showed that melatonin accelerated this process, especially at the middle stages corresponding to the proliferation phase (days 3-6 after surgery). Histological analysis revealed intensification of epidermal cell proliferation at the edges of the wound starting from day 4 after surgery.
Asunto(s)
Gangliósido G(M1)/farmacología , Queratinocitos/efectos de los fármacos , Melatonina/farmacología , Repitelización/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Animales , Bovinos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Piel/crecimiento & desarrolloRESUMEN
The kinetics of protein synthesis was investigated in primary cultures of hepatocytes from old rats in serum-free medium. The rats were fed mixed fodder supplemented with glutamic acid and then transferred to a regular mixed fodder. The amplitude of protein synthesis rhythm in hepatocytes isolated from these rats increased on average 2-fold in comparison with the rats not receiving glutamic acid supplement. Based on this indicator reflecting the degree of cell-cell interactions, the cells from old rats were not different from those of young rats. The effect was preserved for 3-4 days. These results are discussed in connection with our previous data on preservation of the effect of single administration of gangliosides, noradrenaline, serotonin, and other synchronizers on various cell populations. In contrast to the other investigated factors, glutamic acid is capable of penetrating the blood-brain barrier, which makes its effect possible not only in the case of hepatocytes and other non-brain cells, but also in neurons.
Asunto(s)
Comunicación Celular/efectos de los fármacos , Ácido Glutámico/farmacología , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Proteínas Quinasas/biosíntesis , Animales , Ácido Glutámico/administración & dosificación , Cinética , Ratas , Ratas WistarRESUMEN
The protein subunit of RNase P from a thermophilic bacterium, Thermotoga maritima, was overexpressed in and purified from Escherichia coli. The cloned protein was reconstituted with the RNA subunit transcribed in vitro. The temperature optimum of the holoenzyme is near 50 degrees C, with no enzymatic activity at 65 degrees C or above. This finding is in sharp contrast to the optimal growth temperature of T.maritima, which is near 80 degrees C. However, in heterologous reconstitution experiments in vitro with RNase P subunits from other species, we found that the protein subunit from T.maritima was responsible for the comparative thermal stability of such complexes.
Asunto(s)
Endorribonucleasas/genética , Endorribonucleasas/metabolismo , Proteínas de Escherichia coli , ARN Catalítico/genética , ARN Catalítico/metabolismo , Thermotoga maritima/enzimología , Thermotoga maritima/genética , Secuencia de Aminoácidos , Aminoácidos/análisis , Endorribonucleasas/química , Endorribonucleasas/aislamiento & purificación , Estabilidad de Enzimas , Escherichia coli/enzimología , Escherichia coli/genética , Holoenzimas/química , Holoenzimas/genética , Holoenzimas/aislamiento & purificación , Holoenzimas/metabolismo , Cinética , Datos de Secuencia Molecular , Subunidades de Proteína , ARN Bacteriano/genética , ARN Bacteriano/aislamiento & purificación , ARN Bacteriano/metabolismo , ARN Catalítico/química , ARN Catalítico/aislamiento & purificación , ARN de Transferencia de Tirosina/genética , ARN de Transferencia de Tirosina/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Ribonucleasa P , Alineación de Secuencia , Temperatura , Transcripción GenéticaRESUMEN
If the human skin is not exposed to solar radiation (direct or scattered) for long periods of time, disturbances will occur in the physiological equilibrium of the human system. The result will be functional disorders of the nervous system, a vitamin D deficiency, a weakening of the body's defenses, and an aggravation of chronic diseases. Sunlight deficiency is observed more particularly in persons living in the polar regions and in those working underground or in windowless industrial buildings. The simplest and at the same time the most effective measure for the prevention of this deficiency is the irradiation of human beings by means of uv lamps. Such irradiation is conducted either in special rooms called photaria or directly in locations where persons are regularly present-in workshops, schools, hospitals, etc. As a rule, the daily dosage of uvdoes not exceed half of the average dose which produces a just perceptible reddening of an untanned human skin. It is preferable to use fluorescent lamps which use phosphorous and have maximum emission of 315 nm. The beneficial effect of uv irradiation has been confirmed by many years of experience. Ultraviolet irradiation is also beneficial for agricultural animals. In addition to the lamps used for irradiation of human beings, high pressure mercury lamps in a quartz envelope are used to irradiate animals. Irradiation doses vary according to the species ani age of the animals.
