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991.
CS Bedetti NC Jorge FCG Trigueiro GP Bragança LV Modolo 《Biotechnic & histochemistry》2018,93(2):149-154
We report a new method for histochemical localization of cytokinins (CKs) in plant tissues based on bromophenol blue/silver nitrate staining. The method was validated by immunohistochemistry using anti-trans-zeatin riboside antibody. Indole-3-acetic acid (auxin, IAA) was localized by anti-IAA antibody in plant tissues as a proof for IAA histolocalization. We used root sections, because they are major sites of CKs synthesis, and insect galls of Piptadenia gonoacantha that accumulate IAA. Immunostaining confirmed the presence of zeatin and sites of accumulation of IAA indicated by histochemistry. The colors developed by histochemical reactions in free-hand sections of plant tissues were similar to those obtained by thin layer chromatography (TLC), which reinforced the reactive sites of zeatin. The histochemical method for detecting CKs is useful for galls and roots, whereas IAA detection is more efficient for gall tissues. Therefore, galls constitute a useful model for validating histochemical techniques due to their rapid cell cycles and relatively high accumulation of plant hormones. 相似文献
992.
Liam Chung Erik Thiele Orberg Abby L. Geis June L. Chan Kai Fu Christina E. DeStefano Shields Christine M. Dejea Payam Fathi Jie Chen Benjamin B. Finard Ada J. Tam Florencia McAllister Hongni Fan Xinqun Wu Sudipto Ganguly Andriana Lebid Paul Metz Sara W. Van Meerbeke Franck Housseau 《Cell host & microbe》2018,23(3):421
993.
Lindsay B. Avery Jason Wade Mengmeng Wang Amy Tam Amy King Nicole Piche-Nicholas 《MABS-AUSTIN》2018,10(2):244-255
Implementation of in vitro assays that correlate with in vivo human pharmacokinetics (PK) would provide desirable preclinical tools for the early selection of therapeutic monoclonal antibody (mAb) candidates with minimal non-target-related PK risk. Use of these tools minimizes the likelihood that mAbs with unfavorable PK would be advanced into costly preclinical and clinical development. In total, 42 mAbs varying in isotype and soluble versus membrane targets were tested in in vitro and in vivo studies. MAb physicochemical properties were assessed by measuring non-specific interactions (DNA- and insulin-binding ELISA), self-association (affinity-capture self-interaction nanoparticle spectroscopy) and binding to matrix-immobilized human FcRn (surface plasmon resonance and column chromatography). The range of scores obtained from each in vitro assay trended well with in vivo clearance (CL) using both human FcRn transgenic (Tg32) mouse allometrically projected human CL and observed human CL, where mAbs with high in vitro scores resulted in rapid CL in vivo. Establishing a threshold value for mAb CL in human of 0.32 mL/hr/kg enabled refinement of thresholds for each in vitro assay parameter, and using a combinatorial triage approach enabled the successful differentiation of mAbs at high risk for rapid CL (unfavorable PK) from those with low risk (favorable PK), which allowed mAbs requiring further characterization to be identified. Correlating in vitro parameters with in vivo human CL resulted in a set of in vitro tools for use in early testing that would enable selection of mAbs with the greatest likelihood of success in the clinic, allowing costly late-stage failures related to an inadequate exposure profile, toxicity or lack of efficacy to be avoided. 相似文献
994.
PÉTER KOVÁCS WERNER E. G. MÜLLER GYÖRGY CSABA 《The Journal of eukaryotic microbiology》1997,44(5):487-491
ABSTRACT. By use of a monoclonal antibody directed against purified lectin from the sponge Geodia cydonium it was demonstrated that the mucocysts of Tetrahymena pyriformis contain a substance immunologically similar to that found in G. cydonium . In extracts of T. pyriformis the monoclonal antibody recognizes a 36 kDa protein; binding could be abolished by adsorption of the antibody with (i) crude extract, (ii) purified lectin from G. cydonium and (iii) a 29 aa long peptide. In addition the data show that 10-6 M of insulin causes first the release of mucocyst material, which reacts with the lectin antibody, and second its subsequent redistribution on the surface of the somatic cilia and the oral field. 相似文献
995.
K. S. Sturm Christoph N. Berger Sheila X. Zhou Sally L. Dunwoodie Seong-Seng Tan Patrick P. L. Tam 《Development genes and evolution》1997,206(6):377-388
The developmental potential of parthenogenetic embryonic stem (P-ES) cells was studied in teratomas and mouse chimaeras.
Teratomas derived from P-ES cells contained a mixture of tissue types with variable proportions of specific tissues. Three
of the eight P-ES cell lines analysed showed high proportions of striated muscle in teratomas, similar to teratomas from normal
embryos or ES cell lines derived from fertilised embryos (F-ES cells). Our study also revealed that one P-ES cell line showed
little lineage restriction in injection chimaeras. Descendants of the P-ES cells contributed to most tissues of chimaeric
fetuses in patterns similar to F-ES cells. Normal colonisation of muscle, liver and pancreas was found in adult chimaeras.
P-ES cells also showed similar haematopoietic differentiation and maturation as F-ES cells. However, extensive P-ES cell contribution
was associated with a reduction in body size. These findings suggest that, while P-ES cells display more extensive developmental
potential than the cells of parthenogenetic embryos from which they were derived, they only retained properties related to
the presence of the maternal genome. To elucidate the molecular basis for the lack of lineage restriction during in vivo differentiation,
the expression of four imprinted genes, H19, Igf2r, Igf2 and Snrpn was compared among five P-ES and two F-ES cell lines. Expression levels of these genes varied among the different ES cell
lines, both in undifferentiated ES cells and in embryoid bodies. 相似文献
996.
Ottó Toldi Gábor Gyulai József Kiss Imre A. Tamás Ervin Balázs 《Plant cell reports》1996,15(11):851-854
An in vitro method was developed for microshoot initiation from thin-layer explants prepared from the elongated epicotyls of sugarbeet (Beta vulgaris L.). Intact epicotyls of 14-day-old seedlings were excised from the hypocotyls above the cotyledons and allowed to elongate on De Greef and Jacobs (1979) medium supplemented with 0.2 mg/l 6-benzyladenine, 0.2 mg/l gibberellic acid and 0.1 mg/l indole-3-acetic acid in darkness. After a 21-day-incubation, the elongated epicotyls were halved to obtain apical and basal segments prior to removing the leaves and lateral buds. Subsequently, 5–8 mm long, 2–3 mm wide and 0.8–1.0 mm thick tangential sections were prepared longitudinally from the exterior parts of the halved epicotyls. These thin-layer explants were incubated on microshoot initiating media containing various growth regulators. The combination of 1.0 mg/l 6-benzyladenine and the antiauxin 2,3,5-triiodobenzoic acid (1.0 mg/l) resulted in maximum microshoot development (6.3±0.2 microshoots/thin-layer explant). The final efficiency of our tissue culture system was significantly increased by the NaCl (100 mg/l) initiated in vitro rooting of microshoot originated plantlets.Abbreviations AC
activated charcoal
-
asdp
apical segment derived plantlet
-
asTLE
apical segment derived thin-layer explant
- BA-6
benzyladenine
-
bsdp
basal segment derived plantlet
-
bsTLE
basal segment derived thin-layer explant
- EEM1-4
epicotyl elongation media
- GA3
gibberellic acid
- GM
germinating medium
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- KN
kinetin
- MES
morpholino-ethanesulfonic acid
- MSI1-6
microshoot initiating media
- NAA
-naphthalene acetic acid
- PGoB
De Greef and Jacobs (1979) medium
- RM1-3
rooting media
- SDM
shoot developing medium
- SE
standard error
- TIBA 2,3,5
triiodobenzoic acid
- TLE
thin-layer explant
- ZEA
zeatin 相似文献
997.
Gábor Nardai Tamás Schnaider Csaba Söti Michael T. Ryan Peter B. Hoj János Somogyi Peter Csermely 《Journal of biosciences》1996,21(2):179-190
The 90 kDa heat shock protein (HSP90) is an ATP-binding molecular chaperone with an associated ATPase activity having nucleoplasmin
and HSP70-binding homology domains and containing Ca-binding EF-hands and a nuclear localization signal. Here we characterize
the HSP90-associated ATPase and show that it is (i) a P-type ATPase inhibited by molybdate and vanadate, (ii) able to hydrolyze
methylfluorescein phosphate with a 5–6-fold higher affinity, (iii) a 3-times better GTPase than ATPase in the presence of
calcium and (iv) HSP27 and F-actin, but not HSP10 can “convert” the HSP90-associated ATPase activity to HSP90 autokinase activity.
The HSP90-associated ATP/GTPase may participate in the regulation of complex formation of HSP90 with other proteins, such
as F-actin, tubulin and heat shock proteins. 相似文献
998.
Istán Pelyvás Ferenc Sztaricskai László Szilágyi Rezsö Bognár József Tamás 《Carbohydrate research》1979,68(2):321-330
A convenient preparative route involving eleven steps starting from D-glucose is described for the synthesis of D-ristosamine (15) hydrochloride. Methyl 2-deoxy-β-D-arabino-hexopyranoside, prepared from 3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-D-arabino-hex- 1-enitol, was benzylidenated, and the product mesylated to give methyl 4,6-O-benzylidene-2-deoxy-3-O-methylsulfonyl-β-D-arabino-hexopyranoside. Azidolysis of this compound and subsequent opening of the 1,3-dioxane ring with N-bromosuccinimide gave methyl 3-azido-4-O-benzoyl-6-bromo-2,3,6-trideoxy-βD-ribo-hexopyranoside. Simultaneous reduction of the azido and bromo groups gave a mixture that was benzoylated to give methyl N,O-dibenzoyl-β-D-ristosaminide and then hydrolyzed to 15 hydrochloride (3-amino-2,3,6-trideoxy-D-ribo-hexopyranose hydrochloride). 相似文献
999.
1 The composition of pome fruit orchard inhabiting spider assemblages was investigated at different geographical scales (Holarctic, European, inter- and intraregional levels within Hungary) using previous faunistic studies and data collected in Hungary between 1995 and 1997. Samples in Hungary were taken from the canopy and herb layer of apple and pear orchards in five markedly different fruit-growing regions by beating and sweep-netting methods. 2 The composition of canopy spider assemblages of apple orchards was analysed for the Holartic region and found to be determined by latitude at family level, and by the main zoogoegraphical regions at genus level. At the European scale, both the genus and species composition changed along a north–south gradient. 3 A comparison among apple and pear orchards located in different regions in Hungary, showed that both foliage- and grass-dwelling spider assemblages varied considerably in species composition and dominance order. 4 Within the same region, both the foliage- and grass-dwelling spider assemblages showed moderate differences in apple and pear orchards submitted to different treatments. Although the assemblages of spiders inhabiting the canopy and the herbaceous layer can be unambiguously distinguished, some overlap still occurs. 5 We conclude that the composition of spider assemblages is basically determined by geographical location. Although both pesticide treatments and available prey densities can influence the population of spiders, such factors are of moderate importance when compared with the effect of regionality, even when considered at smaller scale. However, most members of the family Theridiidae and the large orb-weavers (Araneidae) decreased considerably in treated plots. Scale-specific differences are thus relevant in determining the composition of prey–predator systems in orchards, and should be taken into account when designing integrated pest management (IPM) programs for apple and pear orchards. 相似文献
1000.
H Kraxner L Tamás G Sáfrány O Ribári I Oláh E Hidvégi G Répássy B Szende 《Cell biology international》2001,25(7):599-606
A-431 squamous cell carcinoma cells were treated in vitro with either 4 Gy radiation of 15 (or 45) microg/ml dibromodulcitol (DBD), as well as with combined 4 Gy irradiation and DBD, with the latter as either a pretreatment or post-treatment. DBD alone or in combination with radiation had a greater effect on cell proliferation than the effect of radiation alone. The difference is due to a higher level of apoptosis induced by DBD, especially in conjunction with radiation. Such a combination may therefore be useful in the treatment of squamous cell carcinoma, which in general responds poorly to radiation therapy. 相似文献