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151.
The aim of the study was to determine the influence of certain antibiotics on the production of IFN-gamma by mouse lymphocytes T after four days incubation with Listeria monocytogenes. The level of mouse IFN-gamma was determined by ELISA method (Inter Test-gamma Mouse IFN-gamma Kit, Genzyme). The strongest immunosuppression effect was demonstrated using rifampicin (39 ng/ml IFN-gamma) (Control: 123 +/- 29 ng/ml IFN-gamma, p < 0.05). Lower immunosuppression effects were observed also with cephradine (54 ng/ml IFN-gamma), amikacin (56 ng/ml IFN-gamma) and ticarcillin (83 ng/ml). The obtained results show that all tested cephalosporins (cephamandole, cefotaxime, cephradine) and aminogllycosides (gentamicin, streptomycin, amicacin) inhibit production of IFN-gamma by mouse lymphocytes T. The influence of penicillin G and ampicillin, as well as, erythromycin and lincomycin on the production IFN-gamma was not observed. Our results suggest that rifampicin, ticarcillin, cephalosporins and aminoglycosides act as inhibitors of production IFN-gamma. 相似文献
152.
Aurelijus Zimkus Audrius Misiūnas Larisa Chaustova 《Central European Journal of Biology》2013,8(8):724-729
The effect of Li+ ions as a transformation inducing agent on the yeast cell wall has been studied. Two Saccharomyces cerevisiae strains, p63-DC5 with a native cell wall, and strain XCY42-30D(mnn1) which contains structural changes in the mannan-protein complex, were used. Fourier transform infrared (FT-IR) spectroscopy has been used for the characterization of the yeast strains and for determination of the effect of lithium cations on the cell wall. A comparison of the carbohydrate absorption band positions in the 970–1185 cm?1 range, of Na+ and Li+ treated yeast cells has been estimated. Absorption band positions of the cell wall carbohydrates of p63-DC5 were not influenced by the studied ions. On the contrary, the treatment of XCY42-30D(mnn1) cells with Li+ ions shifted glucan band positions, implying that the cell wall structure of strain XCY42-30D(mnn1) is more sensitive to Li+ ion treatment. 相似文献
153.
154.
SUMMARY: We created and tested Sight, a Java-based package that provides a user-friendly interface to generate and connect agents for automatic genomic data-mining for individual requirements without requiring programming skills from the user. AVAILABILITY: http://physiologie.uni-ulm.de//Seiten/Arbeitsgruppe/Jurkat-Rott/Jurkat-Rott.htm. The system does not require additional components and runs on IBM PCs under Windows (NT 4.0, 2000 and XP) or Linux (Phat 4.0 and Mandrake 9.0). 相似文献
155.
Tomasz Leski Algis Aučina Audrius Skridaila Marcin Pietras Edvardas Riepšas Maria Rudawska 《Mycorrhiza》2010,20(7):473-481
In this paper, we report the effect of Scots pine genotypes on ectomycorrhizal (ECM) community and growth, survival, and foliar
nutrient composition of 2-year-old seedlings grown in forest bare-root nursery conditions in Lithuania. The Scots pine seeds
originated from five stands from Latvia (P1), Lithuania (P2 and P3), Belarus (P4), and Poland (P5). Based on molecular identification,
seven ECM fungal taxa were identified: Suillus luteus and Suillus variegatus (within the Suilloid type), Wilcoxina mikolae, Tuber sp., Thelephora terrestris, Cenococcum geophilum, and Russuloid type. The fungal species richness varied between five and seven morphotypes, depending on seed origin. The
average species richness and relative abundance of most ECM morphotypes differed significantly depending on pine origin. The
most essential finding of our study is the shift in dominance from an ascomycetous fungus like W. mikolae in P2 and P4 seedlings to basidiomycetous Suilloid species like S. luteus and S. variegatus in P1 and P5 seedlings. Significant differences between Scots pine origin were also found in seedling height, root dry weight,
survival, and concentration of C, K, Ca, and Mg in the needles. The Spearman rank correlation coefficient revealed that survival
and nutritional status of pine seedlings were positively correlated with abundance of Suilloid mycorrhizas and negatively
linked with W. mikolae abundance. However, stepwise multiple regression analysis showed that only survival and magnesium content in pine needles
were significantly correlated with abundance of ECM fungi, and Suilloid mycorrhizas were a main significant predictor. Our
results may have implications for understanding the physiological and genetic relationship between the host tree and fungi
and should be considered in management decisions in forestry and ECM fungus inoculation programs. 相似文献
156.
The objectives of this study were to investigate impact of stump and slash removal on growth and mycorrhization of Picea abies seedlings outplanted on a forest clear-cut. Four non-replicated site preparation treatments included: (1) mounding (M), (2)
removal of stumps (K), (3) mounding and removal of logging slash (HM) and (4) removal of logging slash and stumps (HK). Results
showed that height increment of the seedlings was highest in K and lowest in M after the third growing season, and similar
pattern remained after the fourth season. Ectomycorrhizal (ECM) colonisation of seedling roots was highest in M (96.6%) and
lowest in K (72.3%), and even in HK (76.0%) and HM (76.3%). Morphotyping and sequencing of internal transcribed spacer of
fungal ribosomal DNA revealed a total of 13 ECM species. Among those, Thelephora terrestris and Cenococcum geophilum were the most common, found on 27.4% and 26.3% of roots, respectively. The rest of species colonised 26.6% of roots. Richness
of ECM species was highest in M (10 species) and lowest in K (three species). Consequently, stump and slash removal from clear-felled
sites had a positive effect on growth of outplanted spruce seedlings, but negative effect on their mycorrhization. This suggests
that altered soil conditions due to site disturbance by stump and slash removal might be more favourable for tree growth than
more abundant mycorrhization of their root systems in less disturbed soil. 相似文献
157.
Phorbol esters and beta-adrenergic agonists mediate desensitization of adenylate cyclase in rat glioma C6 cells by distinct mechanisms 总被引:7,自引:0,他引:7
Exposure of rat glioma C6 cells to either isoproterenol or 12-O-tetradecanoylphorbol 13-acetate (TPA) resulted in desensitization of isoproterenol-stimulated adenylate cyclase activity. After either treatment, the affinity of beta-receptors for isoproterenol was reduced. Thus, desensitization by TPA or isoproterenol appeared to involve an "uncoupling" of the beta-receptor from the stimulatory regulatory component (Ns) of adenylate cyclase. The activity of Ns, assayed by reconstitution of S49 cyc- adenylate cyclase activity, was found to be unchanged after desensitization. The activity of beta-receptors was measured by inactivating Ns and the catalytic component of adenylate cyclase in C6 membranes and fusing them with membranes lacking beta-receptors. Receptors from isoproterenol-treated C6 cells were less active in "coupling" to the foreign adenylate cyclase than receptors from untreated cells, whereas receptors from TPA-treated cells were fully active. This unexpected latter result was explored further. Lysates from C6 cells were centrifuged on linear sucrose density gradients and the gradient fractions assayed for beta-receptor binding activity. Most of the receptors were recovered in a "heavy" plasma membrane peak but some receptors also appeared in a "light" membrane peak. After treatment of the cells with isoproterenol or TPA, the proportion of receptors in the light peak increased. Prior treatment of the cells with concanavalin A prevented the increase in light receptors caused by isoproterenol or TPA. In addition, the concanavalin A treatment prevented the desensitization of adenylate cyclase caused by TPA but not that caused by isoproterenol. Finally, desensitization of adenylate cyclase was reversed by polyethylene glycol-induced fusion of membranes from cells treated with TPA but not isoproterenol. We conclude that beta-agonists and phorbol esters desensitize adenylate cyclase by distinct mechanisms. Agonists cause a reduction in the functional activity of the beta-receptors followed by a segregation of the receptors into a light membrane fraction devoid of Ns. Phorbol esters do not alter the activity of the receptors but do cause their segregation. 相似文献
158.
J. Bogdanowicz B. Pawłowska A. Ilnicka S. Gawlik-Zawiślak A. Jóźwiak B. Sobiczewska E. Zdzienicka L. Korniszewski J. Zaremba 《Journal of applied genetics》2010,51(2):215-217
Fluorescent in situ hybridization (FISH) was performed in 76 patients referred to our department because of intellectual disability and dysmorphic features that can be related to subtelomeric microaberrations. In all the patients, conventional cytogenetic methods revealed normal karyotype. Four (5.3%) subtelomeric rearrangements were detected by FISH: 2 subtelomeric 1p36 deletions, an unbalanced translocation involving chromosomes 1 and 12 with 1p36 deletion, and a de novo balanced translocation involving chromosomes 19 and 22. Thus, 3 cases of 1p36 subtelomeric deletion were found (3.95%). To confirm subtelomeric rearrangements in 2 patients, comparative genomic hybridization (CGH) was applied. Moreover, 3 cases of polymorphism without phenotypic effects were found: in 2 patients, the polymorphism involved the long arm of chromosome 2 (maternal derivative in both patients), while in the third patient, a polymorphism of the long arm of chromosome 7 was diagnosed. The latter polymorphism was also found in the patient’s mother and grandfather. 相似文献
159.
Synchronization of estrus and ovulation in sows not conceiving in a scheduled fixed-time insemination program 总被引:1,自引:0,他引:1
A field study was conducted to investigate the effectiveness of a treatment with altrenogest, eCG and hCG or the GnRH-analogue D-Phe(6)-LHRH to synchronize estrus and ovulation of sows diagnosed as non-pregnant in order to reintegrate them back into a scheduled fixed-time insemination program. Sows (n=531) diagnosed as non-pregnant by ultrasonography on days 21-35 after insemination were subjected to one of three treatments: (1) 16 mg altrenogest/day/animal orally for 15 days to block follicular growth, followed by injection of 1000 IU eCG intramuscularly (i.m.) 24h after withdrawal of altrenogest to stimulate follicular growth and 500 IU hCG i.m. 78-80 h after eCG to induce ovulation; (2) similar to (1) except that 20mg altrenogest and 800 IU eCG were used and (3) similar to (2) except that 50 microg D-Phe(6)-LHRH was used to induce ovulation. Females were artificially inseminated (AI) twice at 24 and 40 h, respectively, after hCG/D-Phe(6)-LHRH. Success of treatments was checked by ultrasonography of the ovaries. Rates of conception and farrowing (CR, FR), and number of total and live born piglets (TB, LB) were recorded and compared to those of synchronized first served sows. Females had differing ovarian structures prior to treatment. Altrenogest effectively blocked follicular growth in >80% of the females irrespective of dosage, but 16 mg increased the development of polycystic ovarian degeneration. Four to 18% of the females still had corpora lutea after altrenogest. Most females ovulated either between both inseminations or thereafter (P<0.05). Females treated with D-Phe(6)-LHRH tended to ovulate earlier than those injected with hCG. The CR and FR were up to 25% lower for sows diagnosed as non-pregnant than for sows after first service (P<0.05). Among sows diagnosed as non-pregnant the CR was higher in females treated with D-Phe(6)-LHRH (P<0.05). No differences were found in regard to numbers of TB and LB. In conclusion, a treatment with 20mg altrenogest per day per animal, followed by 800 IU eCG and 50 microg the GnRH-analogue D-Phe(6)-LHRH is appropriate to synchronize estrus and ovulation of sows diagnosed as non-pregnant. Whether there might be a need to feed altrenogest for a longer interval of 18 days has to be investigated. 相似文献
160.
Vilma Kaškonienė Paulius Kaškonas Audrius Maruška Ona Ragažinskienė 《Acta Physiologiae Plantarum》2013,35(4):1171-1178
The aim of this study was to evaluate the variation of essential oils composition of Bidens tripartita L. collected during three successive years (2009–2011). Essential oils were obtained by supercritical CO2 extraction, applying gas chromatographic–mass spectrometric (GC–MS) analysis for identification of volatile compounds afterwards. The essential oils of B. tripartita showed a characteristic chemical composition from year to year, observing both quantitative and qualitative compounds differences. The yield of essential oils was 22 and 35 % higher in 2010 year material than in 2009 and 2011 year, respectively. The main compounds found in the B. tripartita essential oils were α-pinene (3.7–12.1 %), p-cymene (2.8–8.0 %), β-ocimene (40.5–45.9 %), β-elemene (9.9–15.6 %), iso and α-caryophyllenes (4.3–6.8 % and 5.2–8.2 %), and α-bergamotene (3.3–9.4 %). To determine the significance of changes in the identified compounds in the samples, representing different plant collection year, statistical hypothesis testing was applied. For classification of these samples to the groups and evaluation of similarity between them principal component analysis, multivariate analysis of variance and hierarchical cluster analysis techniques were used. The correlation analysis helped to find out the strength of linear relationship between amount of each compound and meteorological data (temperature and precipitations). 相似文献