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Metabolic activity of neutrophilic granulocytes of carp (Cyprinus carpio L.) aged from 2 months - 5 years determined by the Nitrotetrazolium blue reduction test (NBT) has been rendered as the percentage of NBT⁺ cells, NBT index and quantity of formazane (g/l). A decrease of the percentage of NBT⁺ cells from the 5th months and the NBT index from the 10 month of the carps lives was discovered. The highest percentage of the NBT⁺ cells and NBT index was found in carps 2 months old, the lowest in the carps at the age of 5 years and 25 months, respectively. Sex did not affect these parameters. Age and sex of the carp did not affect the quantity of formazane in the blood.
The aim this study was to compare metabolic activity of a hollow fiber bioreactor with a perfused liver. A special construction of a hollow fiber bioreactor was used with freshly isolated rat hepatocytes. After isolation, hepatocytes were incubated in the bioreactor for the duration of 3 hrs in the following conditions: 100 ml medium Hanks Balances Salts Solution supplemented with 4% albumin, 2 mM ornithine, 10 mM ammonium chloride and 6 mM ethanol were used; the medium was perfused in a circulated system for 25 ml/min; samples of the medium were taken to estimate ammonia, urea, glucose, lactate, ethanol, AST and ALT activity before and after 5 min and every 15 min of perfusion time. The same experimental condition was used in the perfused rat liver system. Utilization of ammonia was different in both systems and amounted to: 8.89 and 5.23 µmol/h/g hepatocytes in the bioreactor and perfused liver, respectively. Urea production was: 2.35 and 8.22 µmol/h/g hepatocytes, respectively. The largest differences between the compared systems were observed in the glucose and lactate metabolism. The bioreactor did not release glucose and lactate during the entire time of perfusion. In contrast, perfused liver intensively released glucose (31.32 µmol/hr/g cells) and produced lactate (29.42 µmol/hr/g cells). On the other hand, there was no statistically significance difference in the rate of ethanol metabolism between both systems, which amounted to 2.55 and 2.04 umol/h/g hepatocytes in the bioreactor and perfused liver, respectively. The results indicate that a bioreactor with freshly isolated hepatocytes is not bioequivalent to a perfused liver if estimation is made on the basis of ureogenesis and/or glucose utilization. However, ethanol utilization gives evidence that the metabolic activity of the bioreactor is comparable with a perfused liver. On the basis of the obtained results it can be concluded that the difference in metabolic activity of the bioreactor and perfused liver is connected with catabolic state and disturbances of energy metabolism in freshly isolated hepatocytes. In such a condition HBSS is not the proper medium for the recovery of homeostasis. To estimate the metabolic activity of freshly isolated hepatocytes cultivated in various in vitro systems such as a marker of model usefulness it is suggested to use the activity of inducible enzymes, but not constituent enzymes.
Praca zawiera wyniki porównawczych badań kalorymetrycznych, fotosyntezy i transpiracji grochu rosnącego przy optymalnej zawartości wody w glebie oraz w stanie deficytu wody indukowanego przed fazą tworzenia pąków i kwitnieniem. Pomiary kalorymetryczne wykonano w prototypowym izotermicznym, sześcio- celowym kalorymetrze w temperaturze 25°C. Do pomiarów fotosyntezy i transpiracji użyto przenośnego analizatora gazu LI-6400 firmy LI-COR. Deficyt wody w glebie indukowano obniżając jej zawartość w glebie z poziomu 70% PPW do około 30% PPW. Stwierdzone różnice w szybkości wydzielania metabolicznego ciepła, intensywności fotosyntezy i transpiracji były związane z fazą wzrostu grochu i niższe w stanie deficytu wody w glebie.
New trends in evaluation of metabolic activity in brewery yeast strains are described. Such assays include the determination of membrane integrity, profiles of cell components and enzymatic activities. The most monoparametric methods control only one feature - the special character of yeast cell, and the result is the mean for whole cell population. Application of flow cytometry in brewery practice allows to control several vitality parameters simultaneously, and also shows the results of statistical approach.
Lactoferrin (LF) is an iron-binding protein from the transferrin family, present in mucosal secretions, granules of neutrophils and the serum of mammals. Many biological functions have been attributed to lactoferrin, including immunomodulatory and anti-inflammatory properties. Its presence has not been detected in poultry and its influence on their mechanisms of resistance has not been investigated. The aim of present in vitro study was to investigate the influence of bovine lactoferrin on the activity of chicken blood leukocytes. After isolation cells were cultured in complete RPMI - 1640 medium containing 0 (control), 2, 1, 0.5, 0.25 and 0.1 mg/ml of bovine LF, lymphocytes for 48 h and granulocytes for 18 h, respectively. Then the effect of LF on the activity of phagocytes (RBA and PKA tests) and lymphocytes (MTT test) was evaluated. The obtained results suggest that bovine lactoferrin has significant influence on the activity of chicken leukocytes in vitro. The use of LF increased the ability of chicken granulocytes for respiratory burst, however no stimulation of the killing activity was observed. Bovine lactoferrin also increased the proliferative response of lymphocytes T stimulated by ConA, whereas a similar effect on lymphocytes B stimulated by LPS was not noticed. The observed stimulation of the investigated parameters is encouraging for further research concerning the possibility of the use of LF as immunostimulant in poultry husbandry.
The purpose of the study was to evaluate the metabolic activity of neutrophils in pure blood healthy and mastitic cows. Examinations were performed on 10 cows with clinical mastitis, 10 with subclinical mastitis and 10 healthy cows. The blood samples were collected from the coccygeal vessels and milk veins on the first day of clinical mastitis treatment with an intramammary product containing amoxicillin, clavulanic acid and prednisolone (or observation of the other cows) and on 3rd and 7th days. The blood was examined in the following ways: without in vitro stimulation and in vitro stimulation using fMLP, OZ, PMA. The reactive oxygen species (ROS) production was assessed by means of luminol-enhanced chemiluminescence (CL) using a kinetic method for 40 minutes at 38°C, measuring CL at 5 minute intervals (BioOrbit 1251 Luminometer). The area under the curve (integrate) was calculated. Significant differences in CL levels between peripheral blood and blood flowing from the udder were not found, irregardless of the use of stimulators or udder health status. The spontaneous and induced CL level, mainly through means of the receptor, was significantly higher in the blood of mastitic cows in comparison to healthy cows. PMNs from chronic mastitic cows were characterized by weakness of oxygen metabolism and a crucial increase of a stimulated respiratory burst through activation of the protein kinase C way (PMA). A significant decrease of OZ stimulated and non significant decrease of PMA stimulated CL was determined on the 3rd and 7th days after intramammary clinical mastitis treatment; however, the spontaneous CL remained on the same level.
The studies were done on 50 male Wistar rats divided into five groups: 1 - controls, II - rats immobilized for 13 hr, III - animals immobilized after peritoneal infection with a pathogenic E. coli, IV - rats immobilized after the application of vitamin E (30 mg/kg bw) for six continous days, V - rats immobilized after the application of vitamin E and peritoneal injection of a pathogenic E. coli. Metabolic neutrophil activity (NBT-test) was determined spectrophotometrically in blood and the level of corticosterone was estimated in blood plasma by the radiocompetition method. It was found that an increase of corticosterone and decrease of metabolic neutrophil activity appeared in rats after immobilization (group II). However, a significant decrease of neutrophil activity and an inconsiderable increase of corticosterone were noted in group III and V. Immobilization of rats after the administration of witamin E did not affect the level of the examined parameters (group IV).
Omówiono techniki instrumentalne stosowane do wykrywania i określania liczby mikroorganizmów w żywności. Zwrócono uwagę na metody oceniające zmętnienie podłoży spowodowane wzrostem drobnoustrojów (turbidymetria) oraz metody oceniające aktywność metaboliczną istniejących w żywności drobnoustrojów (np. metody elektryczne, mikrokalorymetria, kolorymetria, ultradźwięki, bioczujniki). Ponadto zaprezentowano metody bazujące na oznaczaniu poziomu określonych metabolitów lub składników komórkowych. Zwrócono uwagę na cechy dodatnie i ujemne wymienionych technik oraz podano przykłady ich zastosowań w badaniach żywności.
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