scholarly journals INFLUENCE OF FLURIDONE ON THE CONTENT OF HORMONES IN CALL OF BARLEY CV. STEPTOE AND TS ABA‑DEFICIENT MUTANT AZ34

ÈKOBIOTEH ◽  
2021 ◽  
Vol 4 (1) ◽  
pp. 41-49
Author(s):  
O.A. Seldimirova ◽  
◽  
I.R. Galin ◽  
Keyword(s):  
In Vitro Culture ◽  
Solid Phase ◽  
Inhibitory Effect ◽  
Deficient Mutant ◽  
Solid Phase Assay ◽  
Aba Content ◽  
Endogenous Aba ◽  
Aba Synthesis ◽  
Parental Cultivar

The effect of the inhibitor of endogenous ABA synthesis fluridone on the content and distribution of endogenous ABA and IAA in the calli of ABA-deficient mutant AZ34 barley and its parental cultivar Steptoe was studied using the methods of immuno-enzymatic solid-phase assay and immunolocalization of phytohormones. It was found that by the 4th week of in vitro culture, fluridone causes a significant decrease in the ABA level in calli of both genotypes compared to the control, and the inhibitory effect of fluridone in AZ34 is more pronounced than in Steptoe. In the calli of both genotypes, a significant increase in the IAA content was revealed against the background of a decrease in the ABA content upon treatment with fluridone as compared to the control. It was concluded that ABA plays an important role in the process of embryoido-genesis in vitro.

Effects of (±)-phaseic acid on developing embryos of barley (Hordeum vulgare, L. cv. Bonanza) cultured in vitro

1992 ◽  
Vol 2 (4) ◽  
pp. 207-214 ◽  
Author(s):  
R. D. Hill ◽  
D. Durnin ◽  
L. A. K. Nelson ◽  
G. D. Abrams ◽  
L. V. Gusta ◽  
...  
Keyword(s):  
De Novo ◽  
Protein Accumulation ◽  
Phaseic Acid ◽  
Hordeum Vulgare L ◽  
Two Dimensional Electrophoresis ◽  
Amylase Inhibitor ◽  
Aba Content ◽  
Dimensional Electrophoresis ◽  
Endogenous Aba

AbstractThe effects of exogenous phaseic acid (PA) on germination and protein accumulation of cultured immature barley embryos were examined. Chemically synthesized PA was racemic, 87% pure and stable over the course of the experiment. Germination was observable in >90% of the untreated embryos after 3 days of incubation, whereas embryos treated with 10μm abscisic acid (ABA) or PA showed no evidence of germination. Buffer extracts from embryos treated with ABA or PA had similar protein profiles when examined by single and two-dimensional electrophoresis. The profiles differed significantly from those of embryos incubated in the absence of the two compounds. Concentrations of α-amylase inhibitor and barley-germ agglutinin (BGA) increased upon treatment of immature embryos with ABA or PA. This was due to de novo synthesis as there was increased incorporation of radioactivity from 35S-labelled amino acids into the proteins in treated embryos. Endogenous ABA content in PA-treated embryos was not significantly different from that in untreated embryos. An analogue of ABA, 2′, 3′-dihydroabscisic acid, which cannot be metabolized to phaseic acid, inhibited germination and caused increased synthesis of α-amylase inhibitor and germ agglutinin. ABA and PA may both be active in promoting responses associated with ABA in barley embryos, but the embryos are more sensitive to ABA.

scholarly journals Morphogenesis in vitro and peroxidase activity in barley cv. Steptoe and its ABA-deficient mutant AZ34: effects of inhibitors of ABA synthesis and auxin transport

2020 ◽  
Author(s):  
O. A. Seldimirova ◽  
G. R. Kudoyarova ◽  
I. R. Galin ◽  
D. S. Veselov ◽  
N. N. Kruglova
Keyword(s):  
Peroxidase Activity ◽  
Auxin Transport ◽  
Deficient Mutant ◽  
Barley Mutant ◽  
Morphogenesis In Vitro ◽  
The Relationship ◽  
Aba Synthesis

The relationship between the effect of ABA on morphogenesis in vitro and auxin transport, as well as the role of peroxidases in the action of ABA on morphogenesis in vitro in the ABA-deficient barley mutant AZ34 and its parent form cv. Steptoe was studied.

scholarly journals Inhibitory Effect of Nucleotides on the Multiplication of Babesia gibsoni in Canine Erythrocytes

1970 ◽  
Vol 2 (1) ◽  
pp. 59-61
Author(s):  
MA Hossain ◽  
O Yamato ◽  
M Yamasaki ◽  
Y Maede
Keyword(s):  
In Vitro Culture ◽  
Key Words ◽  
Culture Media ◽  
Inhibitory Effect ◽  
Final Concentration ◽  
Inhibitory Effects ◽  
Babesia Gibsoni ◽  
Significant Inhibitory Effect

The inhibitory effects of nucleotides on the multiplication of Babesia gibsoni was studied on the in vitro culture of canine erythrocytes. B. gibsoni was cultivated at 37°C for 3 days under a humidified atmosphere containing 5% C02, 5% O2, and 90% N2 in  culture media with no nucleotides (Control), cytidine 5'-monophosphate (5'-CMP), uridine 5'-monophosphate (5'-UMP), uridine 3'-monophosphate (3'-UMP), thymidine 3'-monophosphate (3'-TMP) and inosine 5'-monophosphate (5'-IMP), adenine 5'-monophosphate (5'-AMP) and guanine 5'-monophosphate (5'-GMP), in which a final concentration of nucleotides was 5 mM. The adding of 5'-CMP, 5'-UMP, 5'-IMP, 5'-AMP and 5'-GMP as artificial nucleotides significantly (p < 0.01) inhibited the multiplication of B. gibsoni in canine erythrocytes. Further more, the 5'-CMP and 5'-IMP showed the dose-dependently significant inhibitory effect on the multiplication B. gibsoni. It may be concluded from these results that the accumulation of specific nucleotides might have inhibited the multiplication of B. gibsoni in canine erythrocytes. Key words: Babesia gibsoni; multiplication inhibition; canine erythrocytes; nucleotides doi: 10.3329/bjvm.v2i1.1937 Bangl. J. Vet. Med. (2004). 2 (1) : 59-61

scholarly journals The production of anti-PF4 antibodies in anti-phospholipid antibody-positive patients is not affected by COVID-19 vaccination

2021 ◽  
Author(s):  
Paola Lonati ◽  
Caterina Bodio ◽  
Mariangela Scavone ◽  
Giuliana Martini ◽  
Elisa Pesce ◽  
...  
Keyword(s):  
Platelet Activation ◽  
Lupus Erythematosus ◽  
Solid Phase ◽  
Clinical Manifestations ◽  
Platelet Factor ◽  
Heparin Treatment ◽  
Before And After ◽  
Solid Phase Assay ◽  
Vitro Effect

Antibodies against cationic platelet chemokine, platelet factor 4 (PF4/CXCL4) have been described in heparin-induced thrombocytopenia (HIT) but also in patients positive for anti-phospholipid antibodies (aPL) even in the absence of heparin treatment and HIT-related clinical manifestations. Anti-PF4 antibodies have been recently described also in subjects who developed thrombosis with thrombocytopenia syndrome (TTS) in association with adenoviral vector-based, but not with mRNA-based COVID-19 vaccines. We investigated whether COVID-19 vaccination affects the production of anti-PF4 immunoglobulins detectable by solid-phase assay in aPL-positive patients and their ability to induce in vitro platelet activation. Anti-PF4 were found in 9/126 aPL-positive patients, 4/50 COVID-19, 9/49 other infections, and 1/50 aPL-negative systemic lupus erythematosus patients. Clinical manifestations of TTS were not observed in any aPL patient positive for anti-PF4, whose sera failed to cause platelet aggregations. The administration of COVID-19 vaccines did not affect the production of anti-PF4 immunoglobulins or their ability to cause platelet aggregation in 44 aPL-positive patients tested before and after vaccination. In conclusion, heparin treatment-independent anti-PF4 antibodies can be found in aPL-positive patients and asymptomatic carriers, but their presence, titer as well as in vitro effect on platelet activation are not affected by COVID-19 vaccination.

scholarly journals A monoclonal anti-DC1 antibody selectivity inhibits the generation of effector T cells mediating specific cytolytic activity.

1982 ◽  
Vol 156 (5) ◽  
pp. 1539-1544 ◽  
Author(s):  
G Corte ◽  
A Moretta ◽  
M E Cosulich ◽  
D Ramarli ◽  
A Bargellesi
Keyword(s):  
Monoclonal Antibody ◽  
T Cells ◽  
In Vitro Culture ◽  
Natural Killer ◽  
Inhibitory Effect ◽  
Cytolytic Activity ◽  
Effector T Cells ◽  
Pokeweed Mitogen ◽  
Cytotoxic Cell

The products of the DC locus have been shown to be structurally different from those of the DR locus. In this paper it is shown that, unlike anti-DR antibodies, a monoclonal antibody directed against DC1 does not affect proliferation of T cells in response to alloantigens or soluble antigens or production of Ig in a pokeweed mitogen-stimulated in vitro culture. However, the anti-DC1 inhibits the generation of effector T cells mediating specific cytolytic activity, whereas no inhibitory effect can be observed on natural killer and antibody-dependent cytotoxic cell activities.

scholarly journals Quantification of Diphtheria Toxin–Mediated ADP-Ribosylation in a Solid-Phase Assay

2007 ◽  
Vol 53 (9) ◽  
pp. 1676-1683 ◽  
Author(s):  
Christopher Bachran ◽  
Mark Sutherland ◽  
Diana Bachran ◽  
Hendrik Fuchs
Keyword(s):  
Enzymatic Activity ◽  
Diphtheria Toxin ◽  
Catalytic Domain ◽  
Solid Phase ◽  
Pseudomonas Exotoxin A ◽  
Adp Ribosylation ◽  
His Tag ◽  
Solid Phase Assay ◽  
Chimeric Toxins

Abstract Background: Because of reduced vaccination programs, the number of diphtheria infections has increased in the last decade. Diphtheria toxin (DT) is expressed by Corynebacterium diphtheriae and is responsible for the lethality of diphtheria. DT inhibits cellular protein synthesis by ADP-ribosylation of the eukaryotic elongation factor 2 (eEF2). No in vitro system for the quantification of DT enzymatic activity exists. We developed a solid-phase assay for the specific detection of ADP-ribosylation by DT. Methods: Solid phase–bound his-tag eEF2 is ADP-ribosylated by toxins using biotinylated NAD+ as substrate, and the transferred biotinylated ADP-ribose is detected by streptavidin-peroxidase. DT enzymatic activity correlated with absorbance. We measured the amount of ADP-ribosylated eEF2 after precipitation with streptavidin-Sepharose. Quantification was done after Western blotting and detection with anti–his-tag antibody using an LAS-1000 System. Results: The assay detected enzymatically active DT at 30 ng/L, equivalent to 5 mU/L ADP-ribosylating activity. Pseudomonas exotoxin A (PE) activity was also detected at 100 ng/L. We verified the assay with chimeric toxins composed of the catalytic domain of DT or PE and a tumor-specific ligand. These chimeric toxins revealed increased signals at 1000 ng/L. Heat-inactivated DT and cholera toxin that ADP-ribosylates G-proteins did not show any signal increase. Conclusions: The assay may be the basis for the development of a routine diagnostic assay for the detection of DT activity and highly specific inhibitors of DT.

scholarly journals Identification of a binding site on retinal transducin α for the phosphodiesterase inhibitory γ subunit

1994 ◽  
Vol 297 (1) ◽  
pp. 87-91 ◽  
Author(s):  
J Cunnick ◽  
C Twamley ◽  
I Udovichenko ◽  
K Gonzalez ◽  
D J Takemoto
Keyword(s):  
Binding Site ◽  
Solid Phase ◽  
Specific Binding ◽  
Dependent Manner ◽  
Gamma Subunit ◽  
High Affinity ◽  
Catalytic Function ◽  
Alpha Beta ◽  
Solid Phase Assay

Transducin alpha (T alpha) activates retinal rod cyclic GMP phosphodiesterase (PDE) by interacting with and removing the inhibitory PDE gamma subunit. A T alpha-PDE gamma complex can be isolated in vitro, and our previous work [Morrison, Rider and Takemoto (1987) FEBS Lett. 222, 266-270; Morrison, Cunnick, Oppert and Takemoto (1989) J. Biol. Chem. 264, 11671-11681] has identified a region of PDE gamma, residues 24-45, that binds to T alpha. The C-terminal region of PDE gamma is the site that interacts with PDE alpha/beta and inhibits catalytic function. The site on T alpha that binds to the PDE gamma 24-45 region has not been identified. Synthetic peptides (15-mers) which span the bovine T alpha sequence were tested for binding to purified recombinant PDE gamma using a solid-phase assay. The peptides were also tested for ability to activate a PDE complex. We have identified a region, residues 250-275 of T alpha, which shows a high affinity of PDE gamma and for the PDE gamma (24-45) binding peptide. The peptide did not bind to the C-terminal residues 50-87 of PDE gamma. Likewise, a region of T alpha, 1-25 did not exhibit high-affinity binding to PDE gamma or to the 24-45 PDE gamma peptide. Specific binding of the 250-275 peptide to PDE gamma was confirmed by its ability to compete with T alpha binding to PDE gamma, although a higher concentration was required (10x). The T alpha-(250-275) peptide activated a fully inhibited PDE alpha beta gamma 2 complex in a dose-dependent manner. These results suggest that a region on T alpha that recognizes the PDE gamma-binding site is found within residues 250-275 of T alpha.

Isohexenylnaphthazarins from Lithospermum canescens (Michx.) Lehm. and Arnebia euchroma (Royle) Jonst. in vitro culture

Planta Medica ◽  
2010 ◽  
Vol 76 (12) ◽  
Author(s):  
K Graikou ◽  
H Damianakos ◽  
K Syklowska-Baranek ◽  
A Pietrosiuk ◽  
M Jeziorek ◽  
...  
Keyword(s):  
In Vitro Culture ◽  
Arnebia Euchroma ◽  
Lithospermum Canescens

Effect of Dipyridamole on Spontaneous Platelet Aggregation in Whole Blood Decreases with the Time After Venepuncture: Evidence for the Role of ADP

1987 ◽  
Vol 58 (02) ◽  
pp. 744-748 ◽  
Author(s):  
A R Saniabadi ◽  
G D O Lowe ◽  
J C Barbenel ◽  
C D Forbes
Keyword(s):  
Platelet Aggregation ◽  
Correlation Coefficient ◽  
Whole Blood ◽  
Blood Platelet ◽  
Inhibitory Effect ◽  
Time Interval ◽  
Adp Receptor ◽  
Spontaneous Platelet Aggregation

SummarySpontaneous platelet aggregation (SPA) was studied in human whole blood at 3, 5, 10, 20, 30, 40 and 60 minutes after venepuncture. Using a whole blood platelet counter, SPA was quantified by measuring the fall in single platelet count upon rollermixing aliquots of citrated blood at 37° C. The extent of SPA increased with the time after venepuncture, with a correlation coefficient of 0.819. The inhibitory effect of dipyridamole (Dipy) on SPA was studied: (a) 10 μM at each time interval; (b) 0.5-100 μM at 3 and 30 minutes and (c) 15 μM in combination with 100 μM adenosine, 8 μM 2-chloroadenosine (2ClAd, an ADP receptor blocker) and 50 μM aspirin. There was a rapid decrease in the inhibitory effect of Dipy with the time after venepuncture; the correlation coefficient was -0.533. At all the concentrations studied, Dipy was more effective at 3 minutes than at 30 minutes after venepuncture. A combination of Dipy with adenosine, 2ClAd or aspirin was a more effective inhibitor of SPA than either drug alone. However, when 15 μM Dipy and 10 μM Ad were added together, the inhibitory effect of Dipy was not increased significantly, suggesting that Dipy inhibits platelet aggregation independent of Ad. The increase in SPA with the time after venepuncture was abolished when blood was taken directly into the anticoagulant containing 5 μM 2ClAd. It is suggested that ADP released from the red blood cells is responsible for the increased platelet aggregability with the time after venepuncture and makes a serious contribution to the artifacts of in vitro platelet function studies.

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