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21.
S. J. Rosochacki J. Po&#;oszynowicz A. B. Piekarzewska 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2000,117(4):261-273
The experiment was conducted to determine the relationship between lysosomal proteinase activities in skeletal muscle and liver of stressed pigs. Six‐month‐old Duroc (D) and Pietrain (P) pigs were randomly assigned to either control (group I) or stressed groups (5 min of stress, group II; 15 min of stress, group III; 30 min of stress, group IV; 60 min of stress, group V). At slaughter, the longissimus dorsi muscle and the liver were taken. The tissues were analysed for cathepsin D, acid autolytic activities without and with pepstatin (inhibitor of cathepsin D) and leupeptin (inhibitor of cysteine proteinases). Both tissues were also analysed for RNA, DNA and protein content. The acute immobilization stress in the prone position caused changes in longissimus dorsi muscle in DNA (26% decrease in D and 35% increase in P pigs), functional cell size, protein/103DNA (FCS) (34% increase in D and 25% decrease in P pigs), increase in acid autolytic activity (AAA) (by 48.3%), pepstatin insensitive acid autolytic activity (PIA) (by 111.8%), leupeptin insensitive acid autolytic activity (LIA) (by 35.8%) in D, but in P pigs by 13.5%, 16.6% and 54%, respectively. The interaction between strain of pigs and stress was also observed, mostly in DNA and AAA's. In the liver, RNA was decreased by 10% in D and by 12.3% in P pigs, DNA by 13% and 24% in D and P pigs, FCS was increased by 13.2% in D and by 22.7% in P pigs; the activity of cathepsin D (CatD) and pepstatin sensitive cathepsin D (PSCatD) increased after 15 min of stress by 9.2% and 9.3% and LIA by 13.7% in D pigs but in P pigs the maximal increase was after 15 min of stress in AAA by 10.3%, in PIA by 13.6% and in LIA by 3.2%. The experiment showed that the proteinase activities in the two different strains of pigs were different. The highest changes were in AAA's in the longissimus dorsi muscle and in CatD and PSCatD in the liver. There was more CatD in the longissimus dorsi muscle and liver of D than P pigs. Although it should be taken with caution, this suggests that other proteinases may be also responsible for the catabolism of proteins. 相似文献
22.
ByS.J. Rosochacki A. M. Konecka A. B. Piekarzewska J. P Poloszynowicz J. Kleweic 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2000,117(3):203-210
Duroc (D) and Pietrain (P) pigs were used to study the effect of acute immobilization stress on carbohydrate metabolism. Changes in the activities of several glycolytic enzymes and the content of glycogen in longissimus dorsi muscle (LDM), glycogen content in the liver and glucose level in plasma were observed. The glycogen level in LDM of pigs was about five times higher in P pigs compared with D ones. The immobilization stress of 15 min caused a decrease of glycogen LDM content by 27% in D and by 44% in P pigs. In the liver, these changes were 75% in P pigs, but in D pigs the glycogen content was lowered during the time of experiment by 37% (control versus 60 min stress). Plasma glucose level was elevated by 118% in D and by 50.5% in P pigs after 15 min of immobilization stress. The activities of the glycolytic enzymes investigated changed in different way in LDM: the PGluM decreased by 20% in D and by 19% in P pigs; the GPI by 8.5% in both strains of pigs; the PFK and PK were higher in D than in P pigs (some statistically significant differences between PK activities of control and 15‐, 30‐ and 60‐min‐stressed animals); the ALD activity was similar in both investigated strains of pigs and LDH was lower in D than in P pigs. It can be assumed that the changes led to the new homeostasis connected with the stress to which the pigs were subjected. 相似文献
23.
Major chemical exchange between the crust and mantle occurs in subduction zone environments, profoundly affecting the chemical evolution of Earth. The relative contributions of the subducting slab, mantle wedge, and arc lithosphere to the generation of island arc magmas, and ultimately new continental crust, are controversial. Isotopic data for lavas from a transect of volcanoes in a single arc segment of northern Honshu, Japan, have distinct variations coincident with changes in crustal lithology. These data imply that the relatively thin crustal lithosphere is an active geochemical filter for all traversing magmas and is responsible for significant modification of primary mantle melts. 相似文献
24.
The kinetics of a first-order, solid-solid phase transition were investigated in the prototypical nanocrystal system CdSe as a function of crystallite size. In contrast to extended solids, nanocrystals convert from one structure to another by single nucleation events, and the transformations obey simple unimolecular kinetics. Barrier heights were observed to increase with increasing nanocrystal size, although they also depend on the nature of the nanocrystal surface. These results are analogous to magnetic phase transitions in nanocrystals and suggest general rules that may be of use in the discovery of new metastable phases. 相似文献
25.
AB Nascimento MS Albornoz L Che JA Visintin V Bordignon 《Reproduction in domestic animals》2010,45(5):851-859
This study investigated the effect of porcine follicular fluid (PFF) and dibutyryl cyclic adenosine monophosphate (dbcAMP) during in vitro maturation (IVM) of porcine oocytes on meiotic maturation, fertilization and embryo development, and compared the effect of supplementing the embryo culture media with PFF or foetal bovine serum (FBS) on embryo development. Oocytes from pre‐pubertal gilts were IVM for 44 h, and parthenogenetically activated or in vitro‐fertilized. Embryos were cultured in porcine zygote medium (PZM3) for 7 days. Cleavage and blastocyst rates were evaluated at 48 h and 7 days of culture. The supplementation of the IVM medium with 25% PFF and 1 mm dbcAMP for the first 22 h resulted in more (p < 0.05) embryos developing to the blastocyst stage as compared with the inclusion of dbcAMP alone. The dbcAMP + PFF combination increased (p < 0.05) the average number of nuclei per blastocyst as compared with either of these components alone or in its absence. A synergistic effect of dbcAMP + PFF during IVM was also reflected in the capacity of oocytes to regulate sperm penetration and prevent polyspermy, as twice as many oocytes from the control group were penetrated by more than one sperm as compared with those matured in the presence of both dbcAMP and PFF. The supplementation of PZM3 with 10% FBS from days 5 to 7 of culture significantly improved the total cell quantity in embryos derived either from control or dbcAMP + PFF matured oocytes. There was no effect on the total cell quantity when FBS was replaced by the same concentration of PFF. These studies showed that dbcAMP, PFF and FBS can improve both the quantity (57.3% vs 41.5%) and quality (74.8 vs 33.3 nuclei) of porcine blastocysts derived from oocytes recovered of pre‐pubertal gilts. 相似文献
26.
Piekarzewska AB Rosochacki SJ Sender G 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2000,47(5):257-269
Concentrations of noradrenaline (NA), adrenaline (A), dopamine (DA), 5-hydroxytryptamine (5-HT), the DA metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) and the main 5-HT metabolite 5-hydroxyindole-3-acetic acid (5-HIAA) were measured using HPLC in 16 brain areas of control and immobilized Pietrain pigs. The animals were immobilized for 15, 30 and 60 min in the prone position. Control pigs showed patterns of regional distribution of brain monoamines similar to those described for rats, dogs and Duroc pigs. However, the absolute values of NA and A in the hypothalamus and preoptic area were much higher than those in rats and dogs, but similar to those in Duroc pigs. The concentrations of dopamine and its metabolites DOPAC and HVA were highest in the caudate nucleus, the nucleus accumbens, the olfactory tubercle and the ventral tegmental area. The distributions of serotonin and its metabolite 5-HIAA were similar in all examined structures. DOPAC/DA and HVA/DA ratios were higher in the cornu ammonis, the hippocampus posterior and the raphe nuclei than in other structures, which suggests brain structure-related differences in dopamine turnover. The greatest decreases in NA and A content were observed in the hypothalamus, the preoptic area and the olfactory tuberculum during the first 30 min of immobilization stress. 5-HT turnover was increased in the raphe nuclei, while DA turnover was affected in the raphe nuclei, the septum, the substantia nigra and the olfactory tubercle. We suggest that acute immobilization stress caused differences in regional patterns of brain biogenic amines, thereby maintaining adequate transmitter levels during stress in stress-susceptible pigs. 相似文献
27.
A transient metastable rotator phase occurring on crystallization of hexadecane into its triclinic phase from the supercooled melt was directly observed with time-resolved synchrotron x-ray scattering. In this system, the limit of supercooling (the crystallization temperature) is determined by the thermodynamic stability of the transient phase with respect to the liquid. The crystallization kinetics of the homologous series of n-alkanes was measured and explained in terms of a crossover from stability to "long-lived" metastability to transient metastability. This crossover allowed further confirmation of the nature of the transient phase. 相似文献
28.
Uri Bargai AB VMD DVSc. Ami Tsvi Nathan DVM Shmuel Pearl DVM 《Veterinary radiology & ultrasound》1991,32(5):259-260
An 18-month-old pregnant heifer, hitherto normal, was noticed to regurgitate wet, partially digested roughage several times a day. On clinical examination, the heifer was losing body weight. There was no obstacle to passing a stomach tube to the rumen. A barium study of the esophagus was performed. Megaesophagus involving the cervical and cranial thoracic esophagus was diagnosed. Postmortem findings were a dilated esophagus, with no gross pathology seen. Histopathology showed extensive submucosal cellular infiltration of eosinophils. The classification and possible etilogy of the case is discussed. 相似文献
29.
In two field trials (T1 and T2), the effect of two different extenders for buck semen was tested. Semen from six (T1) and seven (T2) bucks of the Norwegian Dairy Goat breed was diluted either in a milk‐based extender containing egg yolk (M) or in a commercially available extender without egg yolk [Andromed® (A)]. Dilution in M was performed in a two‐step procedure including centrifugation of the ejaculates and removal of the supernatant, while dilution in A was performed in one step. During the two trials (T1 and T2) 514 and 714, does, respectively, were artificially inseminated during natural oestrus, and the farmers performed the inseminations themselves after attending an artificial insemination (AI) training course. Vaginal insemination with 200 × 106 spermatozoa diluted in M resulted in a 25‐day non‐return rate (NRR) and kidding rate of 37.3% and 24.5%, respectively, while semen diluted in A resulted in 31.7% NRR and a kidding rate of 19.8% (T1). In T2, NRR and kidding rate for AI performed with semen diluted with M were 42.7% and 28.5%, respectively, while dilution in A gave 37.2% NRR and a kidding rate of 26.8%. There was no significant effect of extender in the two trials [T1:p = 0.068 (NRR), p = 0.148 (kidding rate), T2:p = 0.096 (NRR), p = 0.38 (kidding rate)], but farmer had a significant effect on the fertility parameters in both trials. In conclusion, the present studies may indicate that Andromed® is suitable for buck semen. However, more research is necessary to confirm the results and to improve the fertility of does after vaginal AI with frozen‐thawed semen. 相似文献
30.