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151.
152.
Neuroendocrine-immune interactions in fish: a role for interleukin-1   总被引:10,自引:0,他引:10  
Bi-directional communication between the hypothalamus-pituitary-adrenal (HPA)-axis and the sympathetic nervous system with the immune system is crucial to ensure homeostasis. Shared use of ligands and especially receptors forms a key component of this bi-directional interaction. Glucocorticoids (GC), the major end products of the HPA-axis differentially modulate immune function. Cytokines, especially interleukin-1 (IL-1), tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), ensure immune signalling to the neuroendocrine system. In addition, hormones from leukocyte origin such as corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and beta-endorphin, as well as centrally synthesised and secreted cytokines, contribute to the communication network.In teleost fish cortisol is the major product of the hypothalamus-pituitary-interrenal (HPI)-axis which is the teleost equivalent of the HPA-axis. Moderate and substantial increases in cortisol during stressful circumstances negatively affect B-lymphocytes, whereas rescue of neutrophilic granulocytes may support innate immunity. Recent elucidation of lower vertebrate cytokine sequences has facilitated research into neuroendocrine-immune interactions in teleosts and the first evidence for a significant function of interleukin-1 in the bi-directional communication is discussed.  相似文献   
153.
Comparative studies of ionic composition, osmolality, protein concentration and pH of seminal plasma along with spermatozoa concentrations were carried out in stellate sturgeon, Acipenser stellatus, and Russian sturgeon, Acipenser gueldenstaedtii. Analysis of A. gueldenstaedtii sperm showed significantly higher concentrations of Na+ (34.58 ± 4.61 mm ), Ca2+ (0.35 ± 0.12 mm ), Mg2+ (0.70 ± 0.25 mm ), Cl? (13.50 ± 4.04 mm ) and proteins (0.60 ± 0.29 mg/ml) in the seminal plasma than did seminal plasma of A. stellatus: Na+ (20.08 ± 10.75 mm ), Ca2+ (0.28 ± 0.06 mm ), Mg2+ (0.29 ± 0.05 mm ), Cl? (7.50 ± 3.00 mm ) and 0.30 ± 0.11 mg/ml proteins. Significantly higher concentration of K+ (5.42 ± 1.06 mm ) was observed in A. stellatus compared to A. gueldenstaedtii K+ (2.29 ± 0.50 mm ). Concentration of Na+ was positively correlated with osmolality (r = 0.819), levels of Cl? (r = 0.922) and Mg2+ (r = 0.727) and pH (r = 0.848). The concentration of Mg2+ was positively correlated with protein concentration (r = 0.774), Na+ (r = 0.727), Cl? (r = 0.872) and Ca2+ (r = 0.801). A positive relationship was also found between concentration of K+ and spermatozoa concentration (r = 0.709). Results revealed strong inter‐species differences in several parameters. The data should be useful for artificial fertilization and for cryopreservation of sturgeon sperm.  相似文献   
154.
This paper is dedicated to the problem of radioactive contaminated lands?? assessment. We suggest the mechanisms of land value calculation under radionuclide contamination, accountability of such factors as internal and external human irradiation, migration of radionuclides in soil profile, and accountability of the own soil value in the totals sheet, as well as ecosystem services from the assessment facility. The approbation of the suggested method for the conditions of the Tula region is also presented.  相似文献   
155.
Within-leaf variations in cell size, mitochondrial numbers and dark respiration rates were compared in the most recently expanded tip, the mid-section and base of needles of Pinus radiata D. Don trees grown for 4 years in open-top chambers at ambient (36 Pa) or elevated (65 Pa) carbon dioxide partial pressure (p(CO2)a). Mitochondrial numbers and respiratory activity varied along the length of the needle, with the highest number of mitochondria per unit cytoplasm and the highest rate of respiration per unit leaf area at the base of the needle. Regardless of the location of the cells (tip, middle or basal sections), needles collected from trees grown in elevated p(CO2)a had nearly twice the number of mitochondria per unit cytoplasm as those grown in ambient p(CO2)a. This stimulation of mitochondrial density by growth at elevated p(CO2)a was greater at the tip of the needle (2.7 times more mitochondria than in needles grown in ambient CO2) than at the base of the needle (1.7 times). The mean size of individual mitochondria was unaffected either by growth at elevated p(CO2)a or by position along the needle. Tree growth at elevated p(CO2)a had a variable effect on respiration per unit leaf area, significantly increasing respiration in the tip of the needles (+25%) and decreasing respiration at the mid-section and base of the needles (-14% and -25%, respectively). Although a simple relationship between respiration per unit leaf area and mitochondrial number per unit cytoplasm was found within each CO2 treatment, the variable effect of growth at elevated p(CO2)a on respiration along the length of the needles indicates that a more complex relationship must determine the association between structure and function in these needles.  相似文献   
156.
Crystalline abscisin II, with a tentative molecular formula of C(15)H(20)O(4), has been isolated from young cotton fruit. It accelerates abscission when applied in amounts as low as 0.01 microg per abscission zone. It inhibits indoleacetic acid-induced straight growth of Avena coleoptiles but has no gibberellin activity on dwarf maize.  相似文献   
157.
158.
Athymic-nude (nu/nu) mice and normal (nu/+) mice showed no differences in either latent period or incidence of local sarcomas or lung adenomas within 120 days after administration of 3-methylcholanthrene at birth. However, nu/nu mice were incapable of rejecting allogeneic skin grafts for the duration of the experiment. These results argue against an active role of thymus-dependent immunity as a surveillance mechanism preventing tumor development.  相似文献   
159.
In this study, humoral (circulating anti-Leishmania antibodies) and cellular (Montenegro's skin test) immune responses of dogs from an endemic area of visceral leishmaniosis were tested using Leishmania chagasi, Leishmania amazonensis and Leishmania braziliensis antigens. The antibody response was tested in three animal groups, selected according to their anti-L. chagasi antibody activity, as measured by ELISA in the serum: 19 negative (O.D. below 0.30), seven with undefined (O.D. between 0.40 and 0.70) and 12 positive (O.D. above 1.0) ELISA result. In the group of animals with positive ELISA, the antibody activity against L. chagasi antigens (mean O.D.=1.31) was significantly higher (ANOVA, P<0.01) than against L. amazonensis (mean O.D.=0.88) or L. braziliensis (mean O.D.=0.87) antigens. The Montenegro's skin test results obtained with L. chagasi and L. braziliensis antigens showed a fair agreement (kappa=0.309). The same was observed when antigens from L. braziliensis and L. amazonensis were compared (kappa=0.374), whereas a moderate agreement between the results from tests performed with L. chagasi and L. amazonensis antigens was observed (kappa=0.530). The induration areas obtained with L. braziliensis antigen were smaller than those obtained with the other antigens. The data presented herein indicate that the use of antigens from different Leishmania species may interfere with the results of the immunological tests performed in dogs in an endemic area of visceral leishmaniosis.  相似文献   
160.
We investigated effects of Rendement Napole (RN ) genotype on metabolic markers in Ossabaw pigs fed diets with different levels of dietary fat. Thirty‐two pigs, belonging to either the wild‐type (WT , rn+/rn+) or carrier (CAR , RN ?/rn+) genotypes (n  = 16/genotype), were divided into two dietary groups, (high fat [HF ] or low fat [LF ]) diets, for 12 weeks (n  = 8 pigs/genotype/diet) after which pigs were killed for gene expression analysis by RT ‐PCR . Feeding HF diet caused increased daily gain (ADG ,<  .05) and final body weight (BW ) (<  .05) in comparison with the LF diet (<  .05). Feed efficiency (gain:feed) was higher (<  .05) in pigs on the HF and was higher (<  .05) in CAR pigs compared to WT . There was genotype × diet interaction (=  .05) on final BW such that CAR animals on LF diet had the same final BW as animals of both genotypes on HF diet. Carrier pigs on LF diet had higher (<  .05) average daily gain and gain:feed than WT pigs. There was a trend (<  .08) for a higher feed consumption in pigs on the LF diet. Backfat thickness was higher (<  .01) in pigs on the HF diet. Serum triglyceride was higher (0.62 vs. 0.33 mg/dl, <  .01) in pigs on HF diet. Serum insulin was higher (<  .05) in CAR versus WT pigs (0.40 vs. 0.015 μg/ml). Pigs on the HF diet had a higher (<  .05) serum insulin compared to those on the LF diet (0.032 vs. 0.023 μg/ml). Carnitine palmitoyl transferase 1‐alpha was higher (<  .05) in the longissimus dorsi and semitendinosus muscles of pigs on HF diet. Acyl‐CoA oxidase I was elevated (<  .05) in the liver of pigs on HF diet. Fatty acid synthase was lower in the longissimus dorsi muscle, liver and mesenteric fat (<  .05) of carrier pigs. The RN gene regulates specific metabolic markers in the Ossabaw pigs.  相似文献   
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