Mitigating Effect of Nitrates (Monizol) on Pharmacodynamic Shifts in the Cardiovascular System Caused by Radioprotector Indralin.

We studied the effect of radioprotector indralin (B-190) alone or in combination with monizol on BP and HR in rabbits, reduction of blood supply and spleen weight in rats and (CBA×C57Bl/6)F1 hybrids mice, and on blood loss from a wound on tip of the tail in mice. Being an α1-adrenomimetic, indralin caused hypertensive reaction with the development of bradycardia, reduced blood supply and spleen weight, and sharply reduced blood loss from the wound. Monizol as nitrate reduced BP without affecting HR and reduced blood loss from the wound. Monizol administered prior to indralin eliminated radioprotector-induced hypertensive reaction, reduced bradycardia by more than 2 times, and attenuated the effect of indralin on spleen weight and blood loss from the wound by 1.6-1.8 times. Monizol administered after indralin had no effect on shifts in peripheral blood supply caused by the radioprotector.

Pharmacological Analysis of the Therapeutic Effect of Radioprotectors Cystamine and Indralin in the Capacity of Radiomitigators.

The therapeutic radiomitigating effect of cystamine and indralin was studied in experiments on mice and rats and pharmacological analysis of these drugs was carried out. The animals were subjected to whole-body 60Co γ-irradiation. The mice were exposed to single (9-10 Gy) or double (8 Gy) irradiation with an interval of 1 month. The rats were exposed to 10 Gy with partial shielding of the upper quarter of the abdomen. In experiments on mice, pretreatment with reserpine abolished the therapeutic effect of cystamine administered repeatedly every 15 min over 1 h after irradiation. Moreover, summation of the radioprotective and therapeutic effects of the radioprotector was revealed under these conditions. In mice and rats, α1-adrenoreceptor blocker terazosin did not abolish the therapeutic effect of indralin administrated after irradiation, but blocked the radioprotective effect of indralin applied prior to irradiation. At the same time, 5-HT2 serotonin receptor blocker tropoxin abolished the therapeutic effect of indralin without affecting its radioprotective activity.

Radioprotective Properties of Indralin in Combination with Monizol in the Treatment of Local Acute and Delayed Radiation Injuries Caused by Local Skin γ-Irradiation.

Female rats were exposed to local γ-irradiation of the right hindpaw in doses of 30-50 Gy at 131-154 sGy/min dose rate. Radioprotector indralin was administered per os 15 min prior to irradiation, monizol was injected intraperitoneally 5 min after irradiation. Indralin showed marked radioprotective properties both for acute and delayed symptoms of local radiation injuries. In combination with monizol, radioprotective effect of indralin was potentiated to dose reduction factor of 1.4-1.5 both for radiation burn severity reduction and for restriction of postradiational contracture development and amputation of the irradiated limb.

Therapeutic effect of long-term melatonin treatment on the course and fatal outcome of modeled acute radiation sickness.

We studied the effect of long-term administration of melatonin to male C57Bl/6 mice starting from day 3 after whole-body γ-irradiation (9.5-10.0 Gy, 7.7-17.1 cGy/min). It was found that replacement of drinking water with melatonin solution (5 mg/liter) did not reduce the amount of fluid intake throughout the period of acute radiation injury. The daily dose of melatonin was 0.9-1.2 mg/kg body weight (this parameter was lower at the peak of the disease and increased during the recovery stage). Melatonin by more than 20% (p<0.05) improved survival of mice exposed to γ-irradiation in a dose of LD97/30, reduced leukopenia during the stage of acute manifestations of the disease and maximum mortality, and increased blood leukocyte count by 40% (p<0.05) by day 12 after irradiation.

[Combined effect of quercetin and indralin (B-190) in alleviating carboplatin hematologic toxicity].

In experiment conducted on male mice of C57B1/6 line quercetin (80-100 mg/kg injected 60 minutes before carboplatin) or an emergency radioprotector indralin B-190 (50-100 mg/kg injected 5 minutes after carboplatin) decreased the mortality of animals from toxic carboplatin dose of 100 mg/kg from 40% to 10-11% (p < 0.05). In mice receiving both quercetin and B-190 the reduction of carboplatin toxicity evaluated by blood WBC level was even more prominent (p < 0.05). The results were confirmed in rat experiment. In animals receiving both quercetin and B-190 with 50 mg/kg of carboplatin the WBC level was higher (p < 0.05). Quercetin alone had no effect on hematologic toxicity in those settings. Besides, quercetin and B-190 didn't have any effect on RBC level changes.

[The influence of combined application of quercetin and indralin on post-irradiation repair of hematopoiesis in acute radiation injury].

Experiments on mice-hybrids F1(CBA x C57B1/6) have detected a favorable effect of the associated application of quercetin (30-60 minutes before y-exposure of an animal) and a radioprotectant of urgent action indralin (in the case of its application after y-exposure) on a post-irradiation repair of the hematopoietic tissue in acute radiation sickness after y-exposure at a non-lethal dose of 6.7 Gy, which manifested itself in the accelerated formation of endogenous spleen colonies and spleen mass recovery, as well as in the lesser degree of leukopenia on the 12th and the 16th day after acute radiation injury. Quercetin per se did not have a radio-protective effect.

[Radioprotective properties of a radioprotector of emergency action indraline at its adminisration after irradiation in conditions of local shielding of a rat abdomen].

In experiences on white rats at a gamma-irradiation in a lethal dose LD97/30 in conditions of local schielding of an abdomen (in the field of a liver) and application of a radioprotector indraline after irradiation the expressed efficiency of combined protection up to 87.5% is scored at 31.3% of a survival in local schielding of an abdomen group and absence of effect from a drug.

[The characteristic of radioprotective properties of a radioprotectant B-190 at its administration after radiation].

In experiences on mice F1 (CBAxC57B 1/6) at a gamma-irradiation in a lethal dose LD(35-70/30) the radioprotectant B-190 at administration after an exposure would rise an animal survival--on 35-55%, caused the increase of the amount of endogenic colony in a spleen and of leucocytes in blood on 11th and 30th day of an acute radiation desease accordingly. The drug has the effect in the interval of doses from 75 up to 150 mg/kg b.w. with the rise of radioprotective action on dose reduction factor from 1.1 up to 1.22. alpha(1)-adrenoblockers terasosin in a dose of 15 mg/kg b.w. partially would reduce radioprotective properties of B-190 as radioprotectant or and drug of early therapy of acute radiation desease.

[Hygienic analysis of conditions of work at the aircraft repair plants and ways to improve the acoustic situation].

Inspection of the conditions of work at aircraft repair plants showed that employees are impacted by a number of harmful in-plant factors including noise, infrasound, kerosene, microclimate and others. Acoustic conditions correspond to harmful (3.2-3.4) or dangerous (4) classes. The general rating of the conditions of work is determined by the degree of noise harmfulness and danger. To reduce the risk of professional pathologies, employees must use personal means of acoustic protection.

[Morphologic changes in the thyroid of rats after a single and fractional gamma-irradiation].

Asynchronous reactions of the thyroid morphological parameters to ionizing radiation were observed in male rats after 24 hours following single and fractional exposure. In delayed periods the thyroid function was suppressed no matter the dose of single and fractional irradiation.

[Ecological/hygienic and toxicological evaluation of combustion products of aviation kerosene and liquefied natural gas].

Products of kerosene combustion in the present-day aeroengines contain more than 200 compounds of incomplete combustion, partial oxidation, and thermal decomposition of fuel and oil. Most of these are strong toxicants for humans. Increase of temperature in the turbine engine combustion chamber led to production of very toxic nitrogen oxides. In search for the ecologically safe and less toxic alternative attention of fuel engineers was drawn to liquefied natural gas which compares well and even excels kerosene in ecological, economic and many other respects.

[Cryogenic fuels in aviation: pollution reduction]. / Ispol'zovanie kriogennogo topliva v aviatsii -- reshenie problemy po snizheniiu zagriazneniia okruzhaiushchei sredy.

Cryogenic fuels are viewed as an alternative to the commonly used hydrocarbonic fuels. The existing national and international guidelines set limits to the emission of unburned carbohydrates (CnHm), carbon monoxide (CO), nitrogen oxides (NO(x)), and soot (SN); there is also prohibition against premeditated fuel discharge in atmosphere of airports. Whereas the international regulations are constantly revised toward toughening, more than 80% of the plane engines in the Russian civil aviation do not meet both national and international harmful emission limits. One of the ways to resolve the problem is substitution of the liquid carbohydrate fuel (kerosene) by natural gas.

[Depleted uranium: radiation and ecological safety aspects]. / Obednennyi uran: radiatsionnye i ékologicheskie aspekty bezopasnosti.

The authors have analyzed the ecological, sanitary-and-hygienic and medicobiologic aspects of using the impoverished uranium in armaments and military equipment. The influence of impoverished uranium on human body (600 cases) was studied using medicobiologic investigation. It was shown that the particles of aerosol of mixed uranium oxide cause the radiation and chemical damage of kidneys, lungs and other internals. Uranium's alpha-radiation is very effective in induction of biologic effects during internal irradiation. Taking into account that bone tissue is the critical organ for uranium isotopes the medullar tissue is exposed to alpha-radiation. In the armed conflicts of the last decade wide use of armour-piercing means with elements consisted of impoverished uranium has led to the appearance of new technogenic risk factor for the environment and the man.

[Radiation safety of exploitation of radiation sources at the civil aviation airlines]. / Radiatsionnaia bezopasnost' pri ékspluatatsii istochnikov ioniziruiushchikh izluchenii na predpriiatiiakh grazhdanskoi aviatsii.

Radiation risks from isotope-containing equipment, and ionizing and unused X-ray radiation sources are characterized and relevant normative documents with safety requirements to radiation sources installation, radiation safety of aircraft servicing and repair, hand luggage control and heavy luggage registration, personal protection items, system of radiation monitoring at airlines and aircraft works, and liability for breach of performance guidelines are cited.

Effect of radioprotector Indralin on the course of acute GVH disease.

The effect of radioprotector indralin on the graft-versus-host reaction was studied on the model of acute GVH disease induced in mice by intraperitoneal transplantation of 40x10(6)semiallogenic splenocytes. The effect was evaluated by animal mortality from GVH disease. Recipients were male F1(CBAxC57Bl/6) mice exposed to 7 Gy 24 h before transplantation. Donors were male C57Bl/6 mice. Indralin, intraperitoneally injected in a dose of 100 mg/kg 5 min after irradiation attenuated the severity of GVH disease. It eliminated phase I of acute GVH reaction and shifted to the right the dynamics of mortality. Estimated time of 50% mortality (LT50) was prolonged by more than 4 days (the parameter increased by 31.1%). Two (5.7%) animals recovered from acute GVH disease, while all controls died. Indralin treatment after irradiation resulted in a 30% increase in survival of exposed mice.