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Biomedical subjects

I V Maksimov

Publications and source records attributed to I V Maksimov.

At least 19 recordsLinked to original sources
PubMed2006

[Plant resistance inductors and active forms of oxygen. III. The influence of bisol 2 and baitan on morphogenesis and defense response of wheat non-morphogenic callus cells infected with smut agent].

A study was made of the influence of bisol 2 and baitan compounds on morphogenesis and defence response of wheat calluse cells infected with bunt agent in associated with oxalate oxidase activation. After introduction of bisol and baitan into cultivation medium, dense area with meristema zones, germs of shoots and rhizoids appeared on non-morphogenic calluses, which correlated with enzyme activation. Parenchyma-like cells, generating hydrogen peroxide, were seen in the site of pathogen penetration under infestation, but were never revealed in control. Generation of hydrogen peroxide in the site of infection was accompanied with an increased oxalate oxidase activity in the cytoplasmic fraction, and with suppression of this activity in a fraction bound to the cell wall. Both compounds induced oxalate oxidase activity under combined cultivation of wheat calluses with bunt agent.

Adjuvants, Immunologic↗
PubMed2004

[Plant resistance inductors and active forms of oxygen. I. The influence of salicylic acid on hydrogen peroxide production in common cultures of wheat callus and bunt pathogen].

The influence of salicylic acid (SA) on cell resistance to bunt pathogen in wheat calluses has been studied. Cell staining by diaminobenzidin substratum (DAB-cells) was conditioned by hydrogen peroxide (H2O2) generation with the involvement of oxalate oxidase (OO). In the control group, DAB-staining was typical only of rhizoid cells (up to 50%). The infection caused no significant increase in the number of such cells; however, in the zone of fungus penetration parenchyma-like DAB-stained cells were observed (up to 24%). Under the influence of SA, the number of DAB-stained cells did not change, but increased in the zone of fungus penetration (up to 36%). Besides, SA increased OO activity and accelerated proembyogenic complex formation in the calluses, which, unlike rhizoids, were not sensitive to the phytopathogen. The infection caused an increase of OO activity in the cytoplasm and in an intercellular fraction, and an inhibition of an extracellular fraction of the enzyme.

3,3'-Diaminobenzidine↗
PubMed2004

[Plant resistance inductors and active forms of oxygen. II. The influence of chitooligosaccharides on the production of hydrogen peroxide with the involvement of oxalate oxidase in common cultures of wheat calluses and bunt pathogen].

We have studied the influence of various concentrations of chitooligosaccharides (CO) on hydrogen peroxide (H2O2) generation, with the involvement of oxalate oxidase (OO), in rhizoids and in zones of hard brand pathogen penetration, as well as on oxalate oxidase activity in wheat calluses. In the control group, diaminobenzidin (DAB)-staining was typical of 30% of peripheral rhizoid cells, which provided their resistance during infection. In the zone of fungus penetration, the appearance of DAB-stained parenchyma-like cells was observed. Simultaneously, the activity OO cytoplasmic fraction increased, whereas OO activity in its ion-bound fraction was suppressed. Low concentrations of medication induced rhizoid formation, increased the number of DAB-stained cells in the pathogen penetration zone, and induced OO activity in cytoplasmic and ionically cell wall-bound fractions. On the contrary, a high concentration of CO (100 mg/ml) suppressed rhizoid formation, Oo activity and the fungus growth. The discovered correlation between enzymatic activation under CO influence, the high level of protective response during infection, and the intensity of rhizoid formation may suggest the community of protective and morphogenetic mechanisms of reactions in plant cells in respect to hydrogen peroxide production.

3,3'-Diaminobenzidine↗
PubMed2003

"Chitin-specific" peroxidases in plants.

The activity of various plant peroxidases and the ability of their individual isoforms to bind chitin was studied. Some increase in peroxidase activity was observed in crude extracts in the presence of chitin. Activated peroxidases of some species fell in the fraction not sorbed on chitin and those of other species can bind chitin. Only anionic isoperoxidases from oat (Avena sativa), rice (Oryza sativa), horseradish (Armoracia rusticana), garden radish (Raphanus sativus var. radicula), peanut (Arachis hypogaea), and tobacco (Nicotiana tabacum Link et Otto) were sorbed on chitin. Both anionic and cationic isoforms from pea (Pisum sativum), galega(Galega orientalis), cucumber (Cucumis sativus), and zucchini (Cucurbita pepo L.) were sorbed on chitin. Peroxidase activation under the influence of chitin was correlated to the processes that occur during hypersensitive reaction and lignification of sites, in which pathogenic fungus penetrates into a plant. The role of chitin-specific isoperoxidases in inhibition of fungal growth and connection of this phenomenon with structural characteristics of isoperoxidases are also discussed.

Chitin↗
PubMed2002

[Effect of the bioantioxidant histochrome on myocardial injury in reperfusion therapy on patients with myocardial infarction].

AIM: To evaluate effects of histochrome on severity of reperfusion damage in opening of the coronary artery in patients with acute myocardial infarction (MI). MATERIAL AND METHODS: 86 acute MI patients were randomized into three groups. 26 patients of group 1 A received 100 mg histochrome 10 min before and 1 hour after intravenous bolus administration of thrombolytic streptokinase; 20 patients of group 1 B received histochrome by the same scheme on the disease day 1 followed by 100 mg/day for 10 days; 40 control patients have undergone thrombolysis without prophylactic histochrome. RESULTS: In the control group ventricular extrasystoles (VES) arose in 100% patients, in groups 1A and 1B--in 27%. The same picture was observed in relation to episodes of accelerated idioventricular rhythm. Coronary reperfusion was accompanied by fast dynamics of ST segment and ORS complex in the control group. MI focus measured by the Selvester ECG method was less in histochrome groups. After myocardial reperfusion malonic dialdehyde in the serum rose 6 times in the control groups and was slightly elevated in groups 1A and 1B. CONCLUSION: Preventive administration of histochrome before thrombolytic therapy to reperfuse myocardium diminishes reperfusion damage: inhibits activity of lipid peroxidation and development of necrosis focus in acute period of MI.

Antioxidants↗
PubMed2000

[Development of blunt Tilletia caries (D.C.) Tul. pathogen on embryogenic wheat callus].

The development of Tilletia caries on embryogenic and morphogenic wheat calluses from germination of spores up to sorus formation have been investigated. Pathogene growth was similar in variants with wheat calluses of susceptible species Triticum aestivum and resistant species T. timopheevii, but intensity of its development of embryogenic calluses of both species was lower, than on morphogenic. Necrosis of parenchyma-like cells was more distinct in the embryogenic than in morphogenic calluses. It was combined with low accumulation rate of infected cells in embryogenic calluses. Necrosis reduced the healthy cell reproduction in meristem-like cells of morphogenic calluses and thereby additionally decreased resistance of morphogenic calluses to pathogene.

Basidiomycota↗
PubMed1992

[Effectiveness of pre-hospital thrombolytic therapy in acute myocardial infarction].

The efficacy and risk of prehospital thrombolysis for acute myocardial infarction (MI) were evaluated in a randomized trial. Patients received streptokinase, 500,000 U, and heparin, 10,000 U, intravenously within 5-10 minutes before (Group 1, n = 50) or after (Group 2, n = 50) hospital admission. One hundred patients took conventional therapy (Group 3). The mean time interval between the onset of symptoms and thrombolytic therapy was 2.2, 4.5, and 3.8 hours in Groups 1, 2, and 3, respectively (p < 0.001). Severe hemorrhages were absent. The rate of ventricular fibrillation was the same in Groups 1 and 3 prior to hospitalization. Left ventricular contractility was identical in Groups 1 and 2. By the end of the fourth week, Group 1 showed a 14% increase in ejection fraction and a 14.5% decrease in akinetic segment, these parameters substantially unchanged in Group 2. The MI size assessed by ECG and the maximum myoglobin concentrations was significantly less in Group 1 than that in Group 2. The patients from Group 1 had fewer MI complications than those from Groups 2 and 3. Three patients died in Group 1, 6 in Group 2, and 16 in Group 3. (p < 0.05).

Adult↗
PubMed1990

[Changes in contractile function of the left ventricle under the effect of thrombolytic reperfusion of the coronary arteries in acute myocardial infarct].

A total of 73 patients with myocardial infarction (MI) were included into a prospective study involving intravenous and/or intracoronary streptokinase administration. The total ejection fraction (EF) and the extent of left ventricular dys- and akinetic areas were measured by contrast ventriculography in the first 3-9 hours and 4 weeks after the onset of MI symptoms. Coronary reperfusion performed in the first 3 hours after the onset of symptoms in patients with anterior MI (n = 8) and following 3-9 hours (mean 6.6 +/- 0.89 hours) in patients with inferior MI (n = 17) significantly (p less than 0.05) reduced the extent of dys- and akinetic areas from 20.5 +/- 4.16 to 6.0 +/- 3.99 and 10.0 +/- 1.56 to 5.0 +/- 1.74%, respectively) following 4 weeks. EF significantly (p less than 0.01) increased in the former and tended to show an increase from 51.0 +/- 2.44 to 64.0 +/- 2.26% (p less than 0.1) in the latter. In patients with anterior MI (n = 19) there was a tendency to a decrease in the extent of dys- and akinetic areas from 26.0 +/- 2.85 to 17.0 +/- 3.9 (p less than 0.1) following 3-9 hours. No substantial changes were observed in the values of left ventricular dys- and akinesis and EF in patients with anterior (n = 13) and inferior (n = 16) MI without coronary reperfusion.

Coronary Circulation↗