High Molecular Weight AB-Polybenzimidazole and Its Solutions in a Complex Organic Solvent: Dissolution Kinetics and Rheology.

AB-polybenzimidazole (ABPBI) dissolution kinetics in an eco-friendly complex acid-free solvent based on dimethyl sulfoxide (DMSO), methanol and KOH, and the rheological behavior of their solutions are investigated. The optimal component ratio of solvent providing the complete ABPBI dissolution is determined. Methanol containing dissolved KOH contributes to the creation of a single-phase superbasic medium, which accelerates and improves the polymer solubility in a mixture with DMSO, significantly reducing the viscoelasticity of the resulting solution.

Effect of Chronic Administration of Obestatin and Its Fragment FNAP-NH on Behavioral Activity and Nociceptive Threshold in Rats with Normal and Excess Body Weight.

The effects of chronic intranasal administration of 300 nmol/kg obestatin and its fragment FNAP-NH on behavioral activity and nociceptive threshold were examined in male Wistar rats with normal body weight or alimentary obesity. In normal rats, obestatin produced no effect on behavior and nociception, whereas FNAP-NH fragment enhanced risk-taking behavior. Rats with excess body weight demonstrated less pronounced risk-taking behavior and elevated nociceptive threshold in comparison with normal animals, but these differences were abolished by chronic administration of FNAP-NH.

Changes in Behavior and Blood Corticosterone Level in Male and Female Rats after Single Administration of Obestatin Fragment 1-4.

Single administration of the obestatin fragment 1-4 (300 nmol/kg) to male Wistar rats produced a significant weight loss in male rats on observation days 5-8, while in female rats only on day 8. In addition, males demonstrated decreased risk factor in the elevated plus-maze test, but no effect of the preparation on behavior of female rats was revealed. Obestatin fragment 1-4 had no effect on corticosterone level 1 week after single administration in both females and male rats.

[Prophylaxis and treatment of radiation oral cavity mucositis by hydrogel preparations in patients with oropharyngeal cancer].

Development of radiation mucositis in patients with oropharingeal cancer who are treated by radiation therapy leads to constrains breaks, decreases of the quality of life and makes the radiation dose in target insufficient. All above mentioned increases recurrence risk. Since 2010 there was developed and introduced the method of prophylaxis and treatment of radiation injuries of oral cavity in patients with oropharingeal cancer which gives an ability to improve radiation treatment outcomes and the quality of life of patients.

[Radiation pneumonitis in the treatment of early-stage breast cancer].

Despite of improvement of radiotherapy techniques and increasing usage of conformal radiation therapy which provides decrease of dose for normal tissues and organs, cases of radiation-induced injuries are still registrated. The aim of this study is to determine frequency and severity of lung toxicity in 513 breast cancer patients with Tis-2N0-2M0 disease after breast conserving surgery and chemotherapy depending from radiation therapy technique and irradiation volume. It is quite clear that in breast cancer patients frequency of lung toxicity after breast conserving surgery and RT increases from 20-24% when irradiating only breast to 37-41% when irradiating breast and regional lymph nodes.

Effect of anorexigenic peptide obestatin on platelet aggregation and osmotic resistance of erythrocytes.

We studied the effects of the anorexigenic peptide obestatin on the coagulation system and blood rheology (by the parameters of platelet aggregation and osmotic resistance of erythrocytes) in vitro and in vivo. Obestatin inhibited in vitro platelet aggregation in the entire dose range and reduced osmotic resistance of erythrocytes in all doses except 300 nmol/kg (obestatin in a dose of 300 nmol/kg had no effect on this parameter). Similar to the results of in vitro experiments, intranasal, intraperitoneal, and subcutaneous administration of obestatin in a dose of 300 nmol/kg inhibited platelet aggregation and had no effect on the osmotic resistance of erythrocytes.

[Transgenerational effects of prenatal stress of different etiology].

This paper considers the transgenerational effects of prenatal stress of different etiology. The impacts of stress factors on the biochemical and morphofunctional parameters of life of the mother, fetus, and offspring in the first and subsequent generations (F1-F4) are estimated. Particular attention is paid to assessing changes in the parameters of physical development, the state of the hypothalamic-pituitary-adrenal axis, proinflammatory status, behavioral indicators, cognitive performance, and vegetative balance in the post-stress period.

[Transgenerational consequences of acute antenatal stress in pregnant rats].

The aim of the present study was to investigate the effects of acute hypobaric hypoxia in early organogenesis on three following generations including pregnant females (FO) and two generations of their posterity (F1 and F2). Animals of all generations mentioned above demonstrated marked changes in motor and exploratory activity as well as in anxiety level while the litter of F1 and F2 generations showed also changes in learning ability. Besides, acute hypobaric hypoxia interfered in maternal behavior of females of the FO and F1 generations.

Comparative analysis of the effects of various stress factors at the stage of early organogenesis on heart rate variability in pregnant female rats and their offspring.

We studied changes in the autonomic balance of heart regulation (by the parameters of heart rate variability) in non-pregnant female rats and rats on the days 10-11 of pregnancy on the next day after stress provoked by acute hypobaric hypoxia, intermittent normobaric hypoxia, or immobilization. The same parameters were assessed in 36-day-old offspring. In non-pregnant rats, the intermittent hypoxia resulted in a shift of the autonomic balance of heart regulation towards activation of the parasympathetic nervous system; in pregnant females, immobilization led to a shift of the autonomic balance towards the sympathetic nervous system.

[Postnatal behavioral consequences of antenatal intermittent hypoxia experienced during early organogenesis in mature rats].

This study analyses the spontaneous behavior and anxiety-phobic status of mature rats that were subjected to antenatal intermittent hypoxia during the early stages of organogenesis. Antenatal intermittent hypoxia caused a decrease of motor activity as well as an enhanced anxiety level in rats of both sexes, while males appeared to be more sensitive to hypoxic influence. The effects of single antenatal intermittent hypoxia were more expressed than those of double exposure.

Transgeneration effects of antenatal acute hypoxia during early organogenesis.

We studied the effect of acute hypobaric hypoxia in early organogenesis on physiological and behavioral parameters of second-generation albino rats. Antenatal acute hypoxia was followed by physical and sexual retardation, increase in the mortality rate, and behavioral changes in second-generation animals (hypoactivity of males and females on day 22 of life and hyperactivity of males on day 57 of life). Second-generation animals exhibited no gender differences in body weight and horizontal and vertical locomotor activity.

[Influence of antenatal intermittent normobaric hypoxia during early organogenesis on the development of white rats].

The influence of antenatal intermittent normobaric hypoxia during early organogenesis (days 9-10 of intrauterine development) on the physical development, vegetative balance, and antioxidant defense system of 60-day-old rats was studied. Antenatal exposure to intermittent hypoxia resulted in the impaired physical development of all offspring during the early 15-day postnatal period and caused changes in the vegetative balance of heart regulation, which were differently directed in males and females. Moreover, females that survived antenatal hypoxia had a decreased superoxide dismutase activity in the brain, compared to that in the control rats.

Effect of hypoxia during early organogenesis on cardiac activity and noradrenergic regulation in the postnatal period.

Cardiac activity in rats during the postnatal period was studied in vitro and in vivo after exposure of rat pups to antenatal acute hypobaric hypoxia at the stage of organogenesis (day 9-10 of gestation). Cultured cardiomyocytes from rat pups exposed to antenatal hypoxia were characterized by increased rate of contractions and decreased reactivity to norepinephrine. Heart rate elevation, predominance of sympathetic influences on cardiac activity, and significant increase in norepinephrine concentration in the cerebral cortex were found in freely moving animals exposed to antenatal hypoxia.

Peptidergic correction of behavior in adult progeny of albino rats exposed to acute hypoxia during early organogenesis.

Physical development, spontaneous behavior, and training capacity were evaluated in adult progeny of albino rats exposed to acute hypobaric hypoxia on days 9-10 of gestation, corresponding to the early organogenesis period. Prenatal hypoxia caused delayed behavioral disorders, which were more pronounced in females born from mothers with low resistance to hypoxia. Therapeutic intranasal administration of Pro-Gly-Pro peptide in a dose of 1 mg/kg to rat pups on days 13-15 of life completely prevented the negative consequences of acute prenatal hypoxia in adult females and leveled virtually all negative consequences, except delayed physical development, in males.

[Comparative investigation of the delayed effects of prenatal hypoxia in the period of progestation and organogenesis].

The aim of the present study was to compare the survival, physical development and spontaneous behavior of rat pups born from white rats subjected to acute hypobaric hypoxia on the 3rd-5th days of gestation (progestation) period or on the 9-10th day of gestation (period of early organogenesis). It was shown that the delayed effects of progestation hypoxia were less expressed than those following acute hypoxia modeled in the early organogenesis. In latter case, hypoxia led to the increased mortality among rat pups of both sexes while hypoxia-induced delay in physical development and changes in spontaneous behavior and anxiety level were registered up to the 57th day of postnatal period.

[Effect of prenatal hypoxia during organogenesis on albino rat behavior during postnatal period].

The survival rate, physical development, and spontaneous behavior has been evaluated in pups of albino rats exposed to acute hypobaric hypoxia on the 9-10th day of gestation corresponding to the onset of organogenesis. Prenatal hypoxia increased the mortality among the offspring, delayed their physical development, and affected their spontaneous behavior up to the age of 2 months. The females exposed to intrauterine hypoxia proved to be more sensitive to hypoxia than males.

Acute hypoxia during organogenesis affects cardiac autonomic balance in pregnant rats.

Changes in ECG parameters were studied in pregnant rats exposed to acute hypobaric hypoxia during the period of organogenesis (gestation days 9 to 10). Rats with low, medium, and high tolerance to hypoxia exhibited pronounced autonomic nervous system imbalance, which become apparent as a loss of correlation between various parameters of ECG signals recorded at rest and during exposure to some stress factors existing under normal conditions.

[Acute antenatal hypoxia on different stages of embryogenesis changes the offspring behavior patterns and biogenic amine levels].

The effects of acute hypobaric hypoxia on the stages of progestation or beginning of organogenesis on biogenic amines levels in brain stem and cerebral cortex of their mature offspring as well as on their behavior, were investigated. It was shown that acute hypoxia applied in the period of embryonic organogenesis resulted in severe delayed changes in offspring spontaneous behavior and led to marked changes of biogenic amine levels, particularly expressed for dopaminergic system. Females subjected to antenatal hypoxia happened to be more sensitive to its influences than males.

[Influence of isolated virion proteins of hepatitis A virus on the behavior of rats].

Influenza A virus M-proteins can cause depression in experimental animals 1 day after administration. HA and NA, on the contrary, activate motor activity in animals under the similar conditions. The effect of viral proteins is dose-dependent.

The effects of ante- and postnatal hypoxia on the central nervous system and their correction with peptide hormones.

Ante- and postnatal hypoxia significantly worsened the postnatal development of animals. The posthypoxic behavioral model included hyperactivity and decreased learning ability, these being typical manifestations of attention deficit disorder. A peptide constellation prevented and significantly improved posthypoxic postnatal development and eliminated the majority of negative behavioral changes.

Consequences of progestational hypoxia in pregnant rats and its peptide correction (EEG data).

We studied immediate and delayed changes in ECG in female albino rats subjected to acute hypobaric hypoxia on days 4-5 of pregnancy and evaluated the possibility of correction of hypoxia-produced disturbances with some peptides. Acute hypoxia lengthened the mean RR interval, increased heart rate variability, and decreased the monotony index. Hypoxia induced considerable changes in the structure of ECG that reflected the development of arrhythmias and conduction disturbances.

[Prenatal hypoxic stress: physiological and biochemical consequences, correction by regulator peptides].

The review is devoted to the problem of prenatal hypoxia influence on central and vegetative nervous system, cardio-vascular and respiratory systems, cell metabolism. It is shown that perinatal hypoxia is often resulted in severe non-reversal functional disorders of postnatal development based on significant morphological changes. Regulatory peptide pretreatment is discussed as one of the methods for correction of pre- and postnatal hypoxic consequences.