Activity of enzymatic detoxification systems in the mice liver under conditions of different retinoid provision

The activity of cellular components of liver detoxification system was studied under the conditions of the absence of vitamin A stores. It is shown that a decrease of p-hydroxylase and N-demethylase activity of cytochrome P-450 simultaneously with a decrease of glutathione-S-transferase activity takes place in the liver microsomal fraction of vitamin A-deficient animals. At the same time the absence of retinoid stores in knock-out animals influences the decrease of only p-hydroxylase activity of cytochrome P-450 system. The increase in glutathione-S-transferase activity is observed in the liver postmicrosomal fraction in mice, kept on vitamin A-deficient diet, while its parametres in knock-out group animals were not statistically different compared to the control.     

Biochemical features of maize tissues with different capacities to regenerate plants

Metabolic profiling using GC–MS and LC–MS analyses of soluble metabolites and cell wall bound phenolic compounds from maize calluses of different morphogenic competence revealed a number of biochemical characteristics that distinguish tissues with high plant regeneration ability from tissues that cannot efficiently regenerate plants in vitro. Maize cultures of different ages from H99 (compact type I callus) and HiII (friable type II callus) were divided into two different samples: regenerable (R) and non-regenerable (NR) based on known morphologies. Tissues from both genotypes with high morphogenic potential had higher asparagine and aspartate and indole-3-butenol concentrations, decreased sugar and DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) concentrations, low levels of 4-aminobutyric acid (GABA) and chlorogenic acid and lower levels of feruloyl- and sinapoyl glucosides compared to NR tissues. The ether bound cell wall phenolics of tissues with high regeneration potential had higher levels of the predominant G (guaiacyl) units and lower levels of H (p-hydroxyphenyl) and S (syringyl) units and higher ferulic acid/coumaric acid and ferulic acid/diferulic acid ratios. The same trends were found with the ester-bound phenolics of HiII, however, there were only small differences between the H99 R and NR tissues. Concentrations of the major sugars, organic acids, amino acids and soluble aromatic compounds tended to increase as the time after culture initiation increased. The results show that there are differences in general metabolism, phenolic secondary compounds and cell wall composition between R and NR cell types.     

Endogenous scavenger levels (vitamin E and A) of patients with chronic alcoholic liver disease under different environmental conditions.

Serum level of endogenous scavengers (E and A vitamin) was studied in groups of patients with various chronic alcoholic liver diseases and in a healthy control group on polluted and non-polluted areas. Vitamin levels in patients with chronic liver disease are diminished in comparison to the healthy in general, but mainly in the cirrhotic group. Diminution of vitamin E levels was observed in earlier phase of liver disease than that of vitamin A levels. Patients and healthy control on polluted area showed more expressed diminution of vitamin levels than the same groups on non-polluted area. Free radical parameter (RBC diene conjugate content) and characteristic alcoholic parameters (serum GOT, gamma-GT, cholesterol level and liver GOT, gamma-GT content in biopsy specimen) were used to explain the differences between the same investigated groups on polluted and non-polluted areas. As conclusion can be supposed that industrial pollution of environment has a worsening effect in diseases with free radical mechanism.     

Biochemical mechanism of ulcer development under stressful conditions

Using the model of acute immobilizing stress in rats it has been established that the content of N-acetylneuraminic acid, hexoses connected with protein, acid glycosaminoglycanes and fucouse in a structure of gastric mucus increases alongside with growth of proteolytic enzymes activity in it. The received results justify an important role of noncollagenic proteins and proteolytic enzymes in provision of resistancy of stomach mucous membrane and mechanisms of stressory ulcers development.     

A strategy for clone selection under different production conditions

Top performing clones have failed at the manufacturing scale while the true best performer may have been rejected early in the screening process. Therefore, the ability to screen multiple clones in complex fed-batch processes using multiple process variations can be used to assess robustness and to identify critical factors. This dynamic ranking of clones' strategy requires the execution of many parallel experiments than traditional approaches. Therefore, this approach is best suited for micro-bioreactor models which can perform hundreds of experiments quickly and efficiently. In this study, a fully monitored and controlled small scale platform was used to screen eight CHO clones producing a recombinant monoclonal antibody across several process variations, including different feeding strategies, temperature shifts and pH control profiles. The first screen utilized 240 micro-bioreactors were run for two weeks for this assessment of the scale-down model as a high-throughput tool for clone evaluation. The richness of the outcome data enable to clearly identify the best and worst clone as well as process in term of maximum monoclonal antibody titer. The follow-up comparison study utilized 180 micro-bioreactors in a full factorial design and a subset of 12 clone/process combinations was selected to be run parallel in duplicate shake flasks. Good correlation between the micro-bioreactor predictions and those made in shake flasks with a Pearson correlation value of 0.94. The results also demonstrate that this micro-scale system can perform clone screening and process optimization for gaining significant titer improvements simultaneously. This dynamic ranking strategy can support better choices of production clones.     

Odor-sampling time of mice under different conditions

Response accuracy and odor sample times on positive (S+) and negative (S-) trials were recorded for mice trained on a variety of go, no-go odor detection and discrimination tasks. Odor sample time was relatively stable over extended training on the same task, increased during acquisition of difficult tasks, relatively insensitive to reinforcement magnitude, and, in some cases, provided more information regarding task difficulty and discrimination than did response accuracy. Mice generally sampled longer on S- trials in simple odor detection tasks but longer on S+ trials in odor discrimination tasks.     

Chronotoxicity of cyclophosphane under different lighting conditions

Study of the chronotoxicity of cyclophosphamide injected to mice at 18, 24, 6 and 12 o'clock has shown that animals kept under the conditions of natural changes of day and night showed the circadian rhythm of the drug toxicity with the maximal survival of the animals after injection at 24 and 6 o'clock and with the minimal survival after injection at 18 o'clock. In animals maintained under the conditions of artificial constant light the toxicity rhythm was perversed within the first hours after injection and improved on subsequent observation. Moreover the earlier death was marked in these animals.     

Antihypoxic effect of vitamin E and its derivative in rats under modeling of hypoxic conditions of different origin

The increase of ubiquinone content in myocardial mitochondria and succinateubiquinone reductase activity in rat blood leucocytes under hypoxic hypoxia and acute microfocal myocardial damage [table: see text] have been shown. At the same time the succinateubiquinone reductase activity of rat myocardial mitochondria do not change substantially. We simultaneously observe the dramatic drop in NADH-ubiquinone reductase activity under experimental myocarditis. This fact demonstrates higher stability of succinateubiquinone reductase system and differences in metabolical processes under hypoxic conditions of different origin. All vitamin E derivatives studied demonstrate substantial antihypoxic activity, which is connected with increased animals' survivability, ubiquinone content in myocardial mitochondria and stabilization and leveling of succinateubiquinone reducatse activity in rat blood leucocytes. alpha-Tocopherolacetate with shortened to six carbon atoms side chain is the most effective in this respect. We discuss possible mechanisms for the realization of vitamin E and its active derivative's antihypoxic effect.     

Absorption and localization of zinc in the ileum of chicks dependent on provision with vitamin A

Vitamin A increase the accumulation and transport of zinc in the chick ileal mucosa. Regulating effect of this vitamin on the mentioned processes was already observed in the initial stage zinc uptake in the intestinal mucosa--its storage in the mucus layer. Stimulation of zinc absorption by vitamin A can be related to a specific carrier-vitamin A-dependent zinc-binding protein. Presence of zinc in the smooth endoplasmic reticulum of the enterocyte apical zone suggests the role of this organelle in the cation homeostasis in the cell.     

Growth of hybridoma cells under different agitation conditions

Summary The effect of mechanical agitation on hybridoma cell growth was examined in laboratory scale vessels. At an agitation rate four times that required to keep the cells in suspension, both growth rate and growth extent were reduced. However, using the minimum agitation rate required to suspend cells, no adverse effect on cell growth was observed even with a turbine agitator.     

Biochemical changes associated with in vivo RbcL fragmentation by reactive oxygen species under chilling-light conditions

During physiological stress, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) degradation is accelerated, which is considered to be one of the key factors responsible for photosynthetic decline. A recent study has shown that the large subunit (RbcL) of Rubisco is directly fragmented by hydroxyl radicals in Cucumis sativus leaves under chilling-light conditions. In the present study, we investigated biochemical aspects associated with this in vivo RbcL fragmentation by reactive oxygen species. RbcL fragmentation was observed in C. sativus and Phaseolus vulgaris , but not in Solanum lycopersicum , Glycine max , Oryza sativa , Triticum aestivum , Spinacia oleracea or Arabidopsis thaliana . In C. sativus and P. vulgaris , RbcL fragmentation followed the fragmentation of PsaB, while in the other species, PsaB fragmentation did not occur. In C. sativus and P. vulgaris , the activities of antioxidant enzymes decreased dramatically under chilling-light conditions, and the proportion of uncarbamylated Rubisco increased. These data suggest that in vivo RbcL fragmentation under chilling-light conditions is associated with a combination of events, namely, inactivation of antioxidant enzymes, destruction of photosystem I and an increase of uncarbamylated Rubisco, which can produce hydroxyl radicals via the Fenton reaction at the catalytic site of RbcL.     

Fish oil and treatment of cancer cachexia

Cancer cachexia is a syndrome characterized by high prevalence and multifactorial etiology. The pathophysiology of cancer-induced weight loss is mainly due to failure of food intake and to various metabolic abnormalities, including hypermetabolism. Multiple biologic pathways are involved in this process, including pro-inflammatory cytokines, neuroendocrine hormones and tumour specific factors such as proteolysis inducing factor (PIF). As a result, a protein and energy depletion is observed that is greater than what would be expected based on the simple decrease of food intake and is associated with marked reduction of lean body mass (LBM). Therapy requires a multi-model approach with control of reduced food intake and of the metabolic abnormalities. Combination treatment with nutritional support and modulation of metabolic/inflammation changes is promising. In this regard, n-3 fatty acids in dose of at least 1.5 g/day for a prolonged time to advanced cancer patients with weight loss, are associated with an improvement of clinical, biological and functional parameters and with amelioration of quality of life.     

A comparison of hydrogen photoproduction by sulfur-deprived Chlamydomonas reinhardtii under different growth conditions

Continuous photoproduction of H(2) by the green alga, Chlamydomonas reinhardtii, is observed after incubating the cultures for about a day in the absence of sulfate and in the presence of acetate. Sulfur deprivation causes the partial and reversible inactivation of photosynthetic O(2) evolution in algae, resulting in the light-induced establishment of anaerobic conditions in sealed photobioreactors, expression of two [FeFe]-hydrogenases in the cells, and H(2) photoproduction for several days. We have previously demonstrated that sulfur-deprived algal cultures can produce H(2) gas in the absence of acetate, when appropriate experimental protocols were used (Tsygankov, A.A., Kosourov, S.N., Tolstygina, I.V., Ghirardi, M.L., Seibert, M., 2006. Hydrogen production by sulfur-deprived Chlamydomonas reinhardtii under photoautotrophic conditions. Int. J. Hydrogen Energy 31, 1574-1584). We now report the use of an automated photobioreactor system to compare the effects of photoautotrophic, photoheterotrophic and photomixotrophic growth conditions on the kinetic parameters associated with the adaptation of the algal cells to sulfur deprivation and H(2) photoproduction. This was done under the experimental conditions outlined in the above reference, including controlled pH. From this comparison we show that both acetate and CO(2) are required for the most rapid inactivation of photosystem II and the highest yield of H(2) gas production. Although, the presence of acetate in the system is not critical for the process, H(2) photoproduction under photoautotrophic conditions can be increased by optimizing the conditions for high starch accumulation. These results suggest ways of engineering algae to improve H(2) production, which in turn may have a positive impact on the economics of applied systems for H(2) production.     

TheCaesalpinia peltophoroides cell cycle under different aeration conditions

Summary Cell cycle parameters were studied inCaesalpinia peltophoroides meristems proliferating under different oxygen tensions. This species has been selected for mixed planting in degraded areas in Brazil, some of which are occasionally flooded. As the species’ adaptation to oxygen deprivation during flooding is not fully understood, the objective of this study was to characterize the meristematic activity of root cells under various oxygen regimes. Synchronous binucleate cells, induced by a pulse of caffeine, showed a cell-cycle time constant under both control (5.6 mg of O₂ per l) and oxygenated conditions (7.9 and 3.2 mg of O₂ per l). The whole cell cycle lasted 10 h, although the relative duration of metaphase and anaphase/early telophase increased in more hypoxic conditions. The species appeared to utilise oxygen diffusing from the shoot to the root system to maintain cell division and root growth.