Socrates: A Novel N-Ethyl-N-nitrosourea-Induced Mouse Mutant with Audiogenic Epilepsy

Epilepsy is one of the common neurological diseases that affects not only adults but also infants and children. Because epilepsy has been studied for a long time, there are several pharmacologically effective anticonvulsants, which, however, are not suitable as therapy for all patients. The genesis of epilepsy has been extensively investigated in terms of its occurrence after injury and as a concomitant disease with various brain diseases, such as tumors, ischemic events, etc. However, in the last decades, there are multiple reports that both genetic and epigenetic factors play an important role in epileptogenesis. Therefore, there is a need for further identification of genes and loci that can be associated with higher susceptibility to epileptic seizures. Use of mouse knockout models of epileptogenesis is very informative, but it has its limitations. One of them is due to the fact that complete deletion of a gene is not, in many cases, similar to human epilepsy-associated syndromes. Another approach to generating mouse models of epilepsy is N-Ethyl-N-nitrosourea (ENU)-directed mutagenesis. Recently, using this approach, we generated a novel mouse strain, soc (socrates, formerly s8-3), with epileptiform activity. Using molecular biology methods, calcium neuroimaging, and immunocytochemistry, we were able to characterize the strain. Neurons isolated from soc mutant brains retain the ability to differentiate in vitro and form a network. However, soc mutant neurons are characterized by increased spontaneous excitation activity. They also demonstrate a high degree of Ca2+ activity compared to WT neurons. Additionally, they show increased expression of NMDA receptors, decreased expression of the Ca2+-conducting GluA2 subunit of AMPA receptors, suppressed expression of phosphoinositol 3-kinase, and BK channels of the cytoplasmic membrane involved in protection against epileptogenesis. During embryonic and postnatal development, the expression of several genes encoding ion channels is downregulated in vivo, as well. Our data indicate that soc mutation causes a disruption of the excitation-inhibition balance in the brain, and it can serve as a mouse model of epilepsy.

Heart Dysfunction in Essential Hypertension Depends on Systemic Proinflammatory Influences: A Retrospective Clinical Pathophysiological Study

Low-intensity systemic inflammation is an important element of heart failure pathogenesis. The aim of this study is to assess proinflammatory status serum indicators (C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6)) in middle-aged males (M) and females (F) with essential hypertension (HTN) depending on left ventricular (LV) diastolic dysfunction (LVDD). The main group comprised 55 M and 49 F with the first- to second-severity grade HTN with mild heart failure and a preserved LV ejection fraction ≥50%. Patients had sinus rhythm, first or second-severity degree LVDD, LV hypertrophy, left atrium dilatation, and NT-proBNP > 125 pg/mL. Comparison group: 30 hypertensives without cardiac dysfunction; control group: 31 normotensives. Quantitative features were compared using the Mann−Whitney test, median χ2, ANOVA module. Spearman’s rank correlation coefficients were determined to identify the relationship between the proinflammatory pattern and exercise tolerance. Hypertensive M had markedly higher CRP, TNF-α, and IL-6 levels compared to F. All mean values corresponded to reference range. In patients with second-degree LVDD, CRP, TNF-α, and IL-6 levels were significantly greater than in subjects with first-degree LVDD (both within M and within F samples). Significant negative associations between CRP, IL-6, and TNF-α levels and the 6 min walk test existed in hypertensive M and F. The study demonstrated a close relationship between the proinflammatory pattern and LVDD and exercise tolerance indicators, regardless of the hypertensive patient’s sex.

Differences in Fatty Acid Composition between Orb-Weaver Spiders Inhabiting a Riparian Zone and a Steppe Are Associated with the Consumption of Different Chironomid Taxa

Amphibiotic insects, chironomids of the genera Glyptotendipes and Chironomus, which emerged from saline Lake Shira, differed in composition and content of fatty acids, including the essential eicosapentaenoic acid (20:5n-3, EPA), and upon flying out they were concentrated in different territories, the riparian zone and remote arid steppe zone, respectively. Potential consumers of chironomids adults, the orb-weaver spiders Larinoides suspicax, which inhabited both zones, also differed in fatty acid composition. The main difference in their biochemical composition was a significantly higher level of EPA in spiders from the riparian zone that likely to be explained by consumption of the Glyptotendipes adults enriched in this fatty acid and concentrated only within this zone. The higher level of EPA, which is deficient in terrestrial ecosystems, in orb-weaver spiders from the riparian zone of the saline lake may potentially promote a successful survival of the consumers in the arid landscape.

[Mechanisms for the Development of Blood Pressure Variability and the Potential of Antihypertensive Drugs in Their Correction]

Blood pressure variability (BPV) is the fluctuations of blood pressure over a certain period of time under the influence of various factors. The issue of increased BPV is of particular clinical importance due to high predictive value of this parameter as a risk factor for fatal and non-fatal cardiovascular, cerebrovascular and renal events. It is proved that in the BPV increasing, the key role is played by impairments in arterial baroreflexes, which, in turn, are mediated by increased vascular stiffness, impact of angiotensin II and the sympathetic nervous system, endothelial dysfunction, nitric oxide deficiency and aging, including the vascular aging. Antihypertensive drugs that targeting largest amount of pathophysiological mechanisms in BPV increasing have a most advantages in correcting excessive pressure fluctuations. In this regard such drugs are perindopril and amlodipine, which can eliminate almost the entire spectrum of increased BPV causes and, therefore, optimally reduce the cardiovascular risk.

[Single Pill Indapamide and Perindopril Arginine Combination: Optimal Coupling of Vascular Protection and Hemodynamic Risk Factors Reduction in Patients with Essential Arterial Hypertension]

OBJECTIVE

to investigate the impact of indapamide / perindopril single-pill combination (I / P SPC) on arterial stiffness parameters, blood pressure (BP) level and BP variability (BPV) in middle-aged patients with stage II grade 1-2 essential arterial hypertension (EAH). Materials and methods. We retrospectively formed a group of patients with stage II grade 1-2 EAH who had not previously received regular antihypertensive therapy (AHT) (n=52, mean age 52.9±6.0 years). All patients were treated with I / P SPC and all of them achieved target office BP level (less than 140 / 90 mm Hg). After 12 weeks of follow-up (from the time of reaching the target BP) assessment of AHT effectiveness (general clinical data, ambulatory blood pressure monitoring [ABPM], volume sphygmography, echocardiography), and vascular stiffness evaluation were performed.

RESULTS

At the end of follow-up office systolic BP (SBP), diastolic BP (DBP), pulse BP, day-time, night-time and 24‑hour SBP and DBP significantly (p<0.001 for all) decreased. According to the ABPM data day-time, nighttime, and 24‑hour systolic BPV significantly decreased (p=0.029, p=0.006 and p<0.001, respectively); day-time and 24‑hour diastolic BPV also significantly decreased (p=0.001 and p<0.001, respectively). Day-night standard deviation (SDdn) significantly decreased too (p=0.002 and p<0.001, respectively). Volumetric sphygmography showed significant decrease of right cardio-ankle vascular index (CAVI) (from 8.20±1.29 to 7.58±1.44, p=0.001) and of left CAVI (from 8.13±1.40 to 7.46±1.43, p<0.001), as well as reduction of the number o f patients with a right- and / or left-CAVI >9.0 (from 32.7 to 11.5 %, p=0.018). According to assessment of arterial stiffness using the Vasotens24 software package, the arterial stiffness index (ASI) significantly (p<0.001) decreased from 153.5±29.9 to 138.3±20.0 (by -9.2±13.1 %). Transthoracic echocardiography data demonstrated significant decrease (p<0.001) in effective arterial elastance (from 1.82±0.43 to 1.58±0.36 mm Hg; by -11.85±16.29 %) and significant (p<0.001) increase in the arterial compliance - from 1.27±0.34 to 1.54±0.38 mm Hg / ml (+26.95±38.06 %).

CONCLUSION

In AHT naive patients 40-65 years old with stage II grade 1-2 EAH therapy with I / P SPC provided effective 24‑hour BP control, reduced BPV and improved arterial stiffness parameters.

[Cognitive functions, emotional status, MRI measurements in treatment-naïve middle-aged patients with uncomplicated essential arterial hypertension]

AIM

To study cognitive functions, anxiety and depression levels, 24-hour blood pressure (BP) profile, cerebral blood flow (CBF) perfusion in treatment-naive middle-aged patients with uncomplicated essential arterial hypertension (EAH) depending on the white matter hyperintensities (WMH) burden.

MATERIAL AND METHODS

Forty-one hypertensive patients (mean age 46.2±4.6 years) and 41 healthy volunteers (mean age 50.3±6.7 years) were enrolled to the study. All subjects underwent brain MRI (MAGNETOM Skyra 3.0T, T1, T2 FSE, T2 FLAIR, T1 MPRAGE, ASL), Montreal cognitive assessment (MoCa), 10-word learning task, verbal fluency test, trail making test, Stroop color and word test, anxiety and depression assessment with Hamilton rating scales, 24-hour blood pressure monitoring (ABPM).

RESULTS

WMH were found in 22 (53.7%) hypertensive patients and in 3 (7.3%) healthy volunteers (p=0.0002). Hypertensive patients had the significantly lower CBF compared to controls (p<0.001).

CONCLUSION

WMH were identified in treatment-naive middle-aged patients with uncomplicated mild to moderate EAH. There was an association between WMH and lower CBF in the cortical plate of frontal lobes, SBP variability and worse cognition. Cerebral hypoperfusion can cause cognitive impairment even in the earliest stages of EAH, which increases due to emotional disorders.

[Day-by Day Blood Pressure Variability: Methodological Aspects, Prognostic Value, Effects of Antihypertensive Therapy]

In this article we present problems of prognostic value of day-by-day blood pressure (BP) variability, its role in development and progression of damage of target organs in arterial hypertension, and impact on risk of cardiovascular, cerebral-vascular complications, and mortality. We also discuss methodological aspects of assessment of day-by-day BP variability. The article contains literature data on effects of antihypertensive therapy on variability of home BP, and consideration of evidence base of possibilities of the fixed amlodipine/perindopril combination for lowering day-by-day BP variability.

[Blood Pressure Variability. Visit-to-Visit Blood Pressure Variability]

The article is devoted to the modern state of the problem of blood pressure variability (BPV). Along with discussion of classification and methods of diagnosis it contains data on prognostic value of visit-to-visit BPV. We have also reviewed effect on BPV of various regimens of antihypertensive therapy and presented evidence base supporting ability of amlodipine/perindopril fixed dose combination to lower visit-to-visit BPV.

[24‑Hour Arterial Pressure Variability: Prognostic Significance, Methods of Evaluation, Effect of Antihypertensive Therapy]

We discuss in this article problems of prognostic significance of 24‑hour arterial pressure variability (24hAPV), as well as the role of 24hAPV in development and progression of various target organs damage by arterial hypertension. We also present literature data on impact of various regimens of antihypertensive therapy on 24hAPV, and on ability of fixed-dose perindopril/amlodipine to lower 24‑hAPV.

Sip-1 mutations cause disturbances in the activity of NMDA- and AMPA-, but not kainate receptors of neurons in the cerebral cortex

Smad-interacting protein-1 (Sip1) [Zinc finger homeobox (Zfhx1b), Zeb2] is a transcription factor implicated in the genesis of Mowat-Wilson syndrome (MWS) in humans. MWS is a rare genetic autosomal dominant disease caused by a mutation in the Sip1 gene (aka Zeb2 or Zfhx1b) mapped to 2q22.3 locus. MWS affects 1 in every 50-100 newborns worldwide. It is characterized by mental retardation, small stature, typical facial abnormalities as well as disturbances in the development of the cardio-vascular and renal systems as well as some other organs. Sip1 mutations cause abnormal neurogenesis in the brain during development as well as susceptibility to epileptic seizures. In the current study we investigated the role of the Sip1 gene in the activity of NMDA-, AMPA- and KA- receptors. We showed that a particular Sip1 mutation in the mouse causes changes in the activity of both NMDA- and AMPA- receptors in the neocortical neurons in vitro. We demonstrate that neocortical neurons that have only one copy of Sip1 (heterozygous, Sip1^fI/wt), are more sensitive to both NMDA- and AMPA- receptors agonists as compared to wild type neurons (Sip1^wt/wt). This is reflected in higher amplitudes of agonist induced Ca²⁺ signals as well as a lower half maximal effective concentration (ЕC50). In contrast, neurons from homozygous Sip1 mice (Sip1^fI/fI), demonstrate higher resistance to these respective receptor agonists. This is reflected in lower amplitudes of Ca²⁺-responses and so a higher concentration of receptor activators is required for activation.

[A change in adrenal responsiveness in sotalol-treated patients with paroxysmal atrial fibrillation depending on autonomic nervous system tone]

AIM

To evaluate the efficacy of sotalol depending on the magnitude of changes in adrenal responsiveness and autonomic nervous system tone in patients with paroxysmal atrial fibrillation (AF).

SUBJECTS AND METHODS

Twenty-six patients with paroxysmal AF in the presence of coronary heart disease (CHD) and hypertension were examined. Sinus rhythm variability and sympathicotonic and vagotonic disorders were studied in patients with paroxysmal AF before and during sotalol treatment. A commercial Beta-ARM-Agat kit was used to estimate the adrenal responsiveness of erythrocyte membranes (β-APM), which can judge the body's individual sensitivity to β-adrenoblockers.

RESULTS

Sotalol used in the average therapeutic doses of 160-240 mg did not reduce ejection fraction or increase atrioventricular conduction up to abnormal values. In patients with borderline and mild hypertension, the drug lowered blood pressure statistically significantly (p=0.01) and was well tolerated. The drug increased the sensitivity of β-adrenoblockers in patients with adrenergic AF.

CONCLUSION

The effect of sotalol on the autonomic nervous system manifested in the higher power of a high-frequency spectral component of heart rate variability than in that of a low-frequency one. Long-term sotalol administration significantly reduced β-APM, increasing the sensitivity of adrenoceptors.

FOR EXTRAINTESTINAL MANIFESTATIONS OF INFLAMMATORY BOWEL DISEASE IN CHILDREN

Inflammatory bowel disease (IBD) are systemic diseases with different intestinal and extra-intestinal manifestations (ElM). This fact can determin an examination plan and the disease course and prognosis. Up to 8.4% of children with IBD have ELM like the first symptom of the disease. The range of ElM of iBD in children is differ from that one of adult patients: rarer arthropathy and arthritis, skin and liver diseases, an extremely rare eye disease. The physical development disorder is a typical children's manifestation of the IBD, the "failure of the weight curve" is an early symptom of the IBD debut (82% of examined children), especially ulcerative colitis. The article discusses the clinical features and therapy of the most frequent extraintestinal manifestations of IBD in children: skin, mucous, eye diseases, axial and peripheral arthropathies, primary scierosing cholangitis, physical, sexual development disorders, decreased bone mineral density. Most often, we observed patients with arthritis and primary scierosing cholangitis - up to 12.5% of patients with active disease. A growth failure was observed in 20% of children with IBD debut, and remained in 9.7% children despite adequate anti-inflammatory therapy. Decreased bone mineral density in children with IBD observed in 30% cases (ISCD-recommendations). Extraintestinal manifestations are very important to make the early diagnosis of IBD without any intestinal symptoms. The pediatrician can suspect a systemic diseases course. ElMs adversely impact upon patientsquality of life and some can be life-threatening.

[Manifestations of polymorphism of β1-adrenoreceptors in patients with newly diagnosed cardiac rhythm disorders]

Individual peculiarities of the receptor apparatus of cardiomyocytes may determine pathological features of heart activity and susceptibility to pharmaceuticals. The possible role of beta-adrenoreceptor polymorphism in the development of cardiac rhythm disturbances is assessed by PCR. Special attention is given to A145G polymorphism of the ADRB1 gene in 127 patients with primary cardiac rhythm disorders. It was shown that AJ45G polymorphism (Ser49Gly) at DNA sites encoding for the amino acid sequence of beta-1 adrenoreceptors can influence the development of sex-specific cardiac rhythm disorders.

[Symptomatic epilepsy in inflammatory demyelinating diseases]

Based on the own observations, we have summarized the features of symptomatic epilepsy in multiple sclerosis and conducted a clinical analysis of the most diagnostically difficult cases of inflammatory and demyelinating diseases in which epilepsy was the major clinical syndrome. The cases of post-infectious acute disseminated encephalomyelitis, idiopathic cerebral angiitis, Rasmussen's encephalitis are reviewed. Peculiarities of MRI structural brain lesions in these patients are discussed. The use of additional laboratory studies, including a study of cerebrospinal fluid, is considered.

[The role of unconscious emotional-motivational stimuli in heroin addiction]

Eighty patients with heroin addiction, aged from 15 to 20 years (most of them over the age of 16), were examined. The duration of illness was from 6 months to 3 years. The examination was conducted 2-3 weeks after arresting of withdrawal syndrome. In that period, patients had different mental disorders: depressive-dysphoric, neurosis-like, anxiety-hypochondriac, hysteriform and others. The aim of the examination was to find peculiarities of functioning of different cortical regions in the process of appraisal of conscious and unconscious stimuli using the method of visual evoked potentials with P300 recording. Stimuli were words highlighted on the screen--indifferent and potentially significant for a patient (e.g. heroin). The stimulus related to the dominating motivation caused in patients the higher diffuse cortical activation on the unconscious level compared to non-targeted stimuli.

[Metabolic activity of peripheral blood neutrophils during treatment of children with acute lymphoblastic leukemia]

Neutrophilic metabolic activity was studied in 21 children with lymphoblastic leukemia during chemotherapy. After one-year chemotherapy, reduced cell activities of catalase and glutathione reductase were observed in children with septic complications during a follow-up in the presence of lower neutrophilic lactate levels. There was a direct correlation between lactate levels and catalase activity. Since the reduction in the levels of lactate in the neutrophils is attended by their apoptosis, this suggests that there is an association of delayed cell death with a fall in the phagocytic antioxidative defense potential.

[Use of venofer for iron deficiency correction in patients undergoing programmed hemodialysis]

AIM

To study iron metabolism in patients on programmed hemodialysis (PH) in oral and intravenous administration of iron drugs; to compare clinical and financial results of using such drugs.

MATERIAL AND METHODS

A two-stage trial studied iron metabolism in 158 PH patients on replacement therapy with erythropoetin. They received correction of iron deficiency with oral drugs (stage I) and venofer (stage II).

RESULTS

The study of iron metabolism has found its deficiency in 2/3 patients receiving oral iron: absolute (48%) and relative (20%). Administration of venofer led to a 2-fold increase in the number of patients with normal iron metabolism. The target Hb and Ht were achieved in 2.5 times more patients than before venofer treatment. The dose of erythpoetin in such cases was reduced by 40%. Side effects were not observed. The week cost of venofer treatment per patient was lower by 22.5$ than the cost of treatment with oral iron drugs.

CONCLUSION

Venofer correction of iron deficiency in PH patients is more effective both clinically and financially than use of oral iron preparations.

[Immunosuppressive components of extracellular lipopolysaccharide highly virulent strain Salmonella typhimurium 1468]

Immunosuppressive activity of culture liquid substrate (CFS) of highly virulent strain Salmonella typhimurium has been studied. A model of delayed hypersensitivity (DHS) to nonbacterial antigen in mice, a method of gel-filtration through the sephadex column G-200, immunosorbents were used. Three components with immunosuppressive activity: thermolabile component and thermostable one with direct immunosuppressive action and the third thermolabile component which manifested inductive immunosuppressive activity only after redox treatment have been revealed in the strain CFS. O-specific and lipid parts were found in the composition of all the components. This allowed them to be related to lipopolysaccharide.

[Immunosuppressive effects of pathogenic gram-negative bacteria]

The review deals with the Immunosuppressive effects of virulent gram-negative bacteria (Salmonella, Shigela, Pseudomonas aeruginosa), with the importance of these effects for the bacteria to survive in the infected body. The above bacteria affect the immunity system in a different way, yet have common features. They are characterized by the occurrence of endotoxin shock, by the suppression of the phagocytic system and cell-mediated immunity. A significant role in suppressing a cellular immune response is played by the lipopolysaccharide of virulent bacteria that greatly differs from that of nonvirulent strains. The immunosuppressive activity of the bacteria and their lipopolysaccharide is closely related to their virulent properties.

[Computed tomography in the evaluation of the bronchopulmonary system in late periods after childhood partial resection of the lung]

The authors used computed tomography (CT) as a basis to analyze the anatomic status of the bronchopulmonary system in 28 patients undergone resection of a part of the lung in childhood for chronic nonspecific lung inflammations and malformations. The findings confirmed the high diagnostic value of CT in the evaluation of the lung in different postoperative periods and showed a certain range of changes varying from significant in the lung operated on to progression of the primary disease to the collateral lung.

[Dependence of immunosuppressive action of lipopolysaccharide on degree of Salmonella pathogenicity]

Immunosuppressive activity of Salmonella typhimurium extracellular lipopolysaccharide (LPS) was studied. In this study isogenic S. typhimurium strains with different degree of virulence were used. The attenuation of these strains was linked with mutations on their chromosome (altered synthesis of RNA polymerase or gyrase DNA) or their own virulence plasmid (the insertion of transposon Tn-5). To obtain LPS fraction with different molecular weights, the filtrate of bacterial culture was subjected to gel filtration through a column packed with Sephadex G-200. The immunosuppressive action of LPS fractions was determined on the model of delayed-type hypersensitivity to nonbacterial antigen in experiments on BALB/c mice. The study revealed that transposon-mediated mutation on plasmid, accompanied by the attenuation of salmonellae, led to the loss of immunosuppressive activity of the high-molecular heat-sensitive component of LPS; only the second heat-resistant component with medium molecular weight retained its activity. The presence of two chromosomal attenuating mutations (rifr nalr) was accompanied by the loss of immunosuppressive activity in both components of LPS.

[Immunosuppressive components of extracellular polysaccharide from Pseudomonas aeruginosa clinical strains]

The immunosuppressive activity of lipopolysaccharide (LPS) contained in filtrates of newly isolated P. aeruginosa cultures was studied. The experimental model of delayed hypersensitivity to non-bacterial antigen in CBA mice and gel filtration through Sephadex G-200 were used. In addition to the already known LPS component with direct immunosuppressive action and having a mol.wt. of 150-800 kD, a new component was detected. It was found to be in inactive state and could be activated by redox treatment, thus becoming capable of inducing capacity for immunosuppression in Escherichia coli. This component had a mol.wt. of 50-70 kD and lost its activity after heating.

[Lipopolysaccharides of Shigella sonnei]

Immunobiological properties of native lipopolysaccharides (LPS) from virulent and avirulent strains of Shigella sonnei bacteria (LPS-V and LPS-A, respectively) were studied. In avirulent bacteria, LPS-V induced immunosuppressive activity specific of the virulent strain. LPS of the avirulent strain, whereas LPS-A lacked this property. Native LPS-V with immunosuppressive activity were isolated from the virulent strain by and immune affinity method. Treatment of LPS-V with phenol or TCA abolished its activity and converted it into the LPS-A form. The data showed that LPS-A can be converted back to the LPS-V form by redox treatment. This approach seems to be promising for activating LPS extracted from cells with TCA or a water-phenol mixture.

[The role of the structural components of bacterial lipopolysaccharide in its inductive immunosuppressive activity]

The inductive immunosuppressive activity of lipopolysaccharides (LPS) and structural parts (O-chains,cor,lipid A) obtained from bacteria of the genus Shigella and Escherichia coli was studied. LPS preparations were extracted by phenol-water method. Its structural components were obtained by the acetic acid hydrolysis and gel filtration. It has been shown that all these preparations did not change the level of delayed type hypersensitivity (DTH) to test-antigen in mice in the case of intraperitoneal injection. They did not also induce immunosuppressive activity in avirulent bacterial strains. After the redox treatment all LPS preparations acquired the ability to induce immunosuppressive property in avirulent bacteria. As a result of redox treatment the immunosuppressive activity appeared in lipid A preparations. O-chains and cor preparations were not active. Immunosuppressive activity was lost after treatment with phenol. It is supposed that active chemical groups are located in lipid A.

[The immunobiological properties of the lipopolysaccharides of bacteria in the genus Shigella with contrasting virulence and their chemically modified analogs]

The antibody formation and expression of delayed type hypersensitivity (DTH) of several antigens under the conditions of their injection together with bacterial lipopolysaccharide (LPS) in mice have been studied. Water-phenol LPS extract from S. sonnei was used. The LPS was treated with the redox system (LPS-R) or not (LPS-PW). Besides, LPS was obtained by immunoaffinity method from avirulent (LPS-A) or virulent (LPS-V) S. sonnei. It had been found that the mice reacted by more intensive increase antibody formation to LPS or sheep erythrocytes if LPS-R or LPS-V were injected alone or together with erythrocytes. More intensive increase of lymph nodes was shown as well. When specified LPS were injected in mice together with E. coli they induced the immunosuppression of DTH. The LPS-PW and LPS-A caused the most feeble reaction of immune system in mice. It has been suggested that the differences of immune reaction are the reflection of conformation processes in LPS molecules.

[The role of the structural parts of bacterial lipopolysaccharide in its direct immunosuppressive activity]

The direct immunosuppressive activity of lipopolysaccharides (LPS) and their structural parts (O-chains, R-core, lipid A), obtained from Salmonella, Pseudomonas and Burkholderia, was studied. LPS preparations were extracted by the phenol-water method. Structural parts of LPS were obtained by acetic acid hydrolysis and gel filtration. The study demonstrated that all these preparations, when injected intraperitoneally into mice, did not affect the level of delayed-type hypersensitivity (DTH) to the test antigen in the animals. After redox treatment all LPS preparations became capable of suppressing DTH. After redox treatment such immunosuppressive activity could be observed in lipid A, while O-specific chains and R-core remained inactive. After phenol treatment immunosuppressive activity disappeared. Chemical groups capable of activation were likely to be located in lipid A or in lipid A-associated protein.

[Immunosuppressive action of lipopolysaccharide S- and R-forms of Salmonella and the role of lipid A]

The immunosuppressive activity of extracellular and water-phenol lipopolysaccharides (LPS) of S.minnesota in S- and R-forms, as well as their gel-filtration, polysaccharide and lipid fractions, was studied in mouse experiments on the model of delayed type hypersensitivity (DTH). The study revealed that the extracellular LPS of S-form S.minnesota was capable of suppressing DTH with lipid A playing the decisive role in this immunosuppressive activity. The extracellular LPS of Reform S.minnesota did not possess the capacity for immunosuppression, but acquired it after redox treatment.

[The inductive immunosuppressive activity of the lipopolysaccharide from Shigella sonnei R forms]

Investigations have been carried out to find the position of lypopolysaccharide (LPS) structural part which can be activated by the redox system and to study peculiarities of its activation. Cell-free culture filtrate (CF) of Shigella sonnei strain R colonies on the nutrient agar medium was used. It was shown that CF contained three active fractions possessing inductive immunosuppressive properties. From all the phenol-water LPS fractions only lipid A possessed activity after redox treatment. O-chain and our fractions did not express such activity. The results of our investigations have shown that inductive immunosuppressive activity of the Shigella sonnei LPS was determined by lipid A.

[The immunosuppressive activity of Shigella sonnei differing by the presence of plasmid pSS120]

S. sonnei virulent strain containing invasiveness plasmid pSS120 was found to suppress delayed hypersensitivity (DH) to nonbacterial antigens. In the filtrate of the culture of this strain extracellular lipopolysaccharide (LPS), capable of inducing immunosuppressing activity in nonvirulent bacteria, was detected. S. sonnei strain having plasmid pSS120 whose invasiveness genes were blocked by the penetration of transposon Tn5, as well as strains containing no invasiveness plasmid, proved to be nonvirulent and could not inhibit immunosuppressing action. Extracellular LPS of nonvirulent strains had no inductive immunosuppressing activity. But it could be activated by chemical treatment. The results of this study indicate that the immunosuppressing action of S. sonnei LPS were linked with some genes of invasiveness plasmid pSS120.

[The immunosuppressive action of different fractions of Salmonella typhimurium lipopolysaccharide]

The suppressing activity of lipopolysaccharide (LPS) of the filtrates of genetically related S. typhimurium 415 and 415/307 cultures with respect to delayed hypersensitivity to nonbacterial antigen in mice was studied. In LPS of the virulent strain two immunosuppressing fractions differing in their molecular weight were detected by the method of gel filtration. One of them was detected in LPS of the genetically related nonplasmid clone of S. typhimurium 415/307. The possibility of the chemical inactivation and reactivation of the immunosuppressing properties of LPS was shown.

[Health status of mining technical school students under present ecological conditions of Donets Basin]

The examinations indicated that the students of mining colleges from Donbass showed unfavourable changes in their health status, including those in their immunobiological resistance and functional status. There was a direct relationship between the levels of environmental pollution and the body's changes, i.e. those in the cardiovascular, respiratory, muscular, and nervous systems. Recommendations for health promotion in the students are given in the paper.

[The immunosuppressive activity of filtrates of the culture broth from nonvirulent salmonellae]

Cultural filtrates (CF) of avirulent Salmonella virchow and Salmonella dublin have been studied for their influence on the delayed type hypersensitivity (DTH) to test-antigen in mice. It is found that i.p. injection of CF inhibits DTH in mice. The immunosuppressive activity is indicated in lipid fraction of CF and it may be removed from CF by the O-specific immunosorbent. It is heat-stable and disappears after phenol or trichloroacetic acid treatment. Gel filtration data evidence for high molecular weight of the active factor. These facts indicate to the connection of immunosuppressive activity with native lipopolysaccharide of avirulent Salmonella.

[The inductive immunosuppressive activity of the nonspecific lipopolysaccharide fraction of virulent Shigella sonnei]

The influence of lipopolysaccharide (LPS) fraction (molecular weight 50-70 kD) of virulent Shigella sonnei on bacterium ability to suppress delayed-type hypersensitivity (DTH) to xenogenic test-antigen in mice has been studied. It is found that single injection of LPS-fraction or bacteria does not inhibit DTH. Intraperitoneal injection of LPS-fraction together with avirulent S. sonnei causes DTH inhibition in mice and at the same time the injection of LPS-fraction together with Staphylococcus or Pseudomonas (extracellular parasites) does not render influence on DTH levels. There is a possibility of LPS-fraction conversion from active to non-active state and back after treatment by trichloracetic acid, phenol or redox system. It is assumed that in Shigella sonnei infection avirulent enteroinvasive bacteria can be involved in immunopathological process due to activity of non-specific fraction of S. sonnei LPS.

[Gram-negative virulent bacterial lipopolysaccharide: role in infection and immunity]

The paper discusses the data available in the literature on the studies on lipopolysaccharides (LPS) of bacteria which show their different virulence. A comparative study of the chemical composition and structure of LPS of the bacteria fails to detect any great difference, but they differ in their biological, especially immunobiological properties. It is suggested that the differences are associated with LPS conformation, chiefly its lipid moiety and ion-coordinating processes and free radical reactions are involved in the conformation. Examining just these phenomena may made advances in further studies of virulent bacterial LPS and possibilities of its use while designing new-generation vaccines.

[The immunomodulating properties of the filtrates of Klebsiella culture broth and the nature of the immunomodulating factor]

Influence of broth culture filtrates (BCF) of Klebsiella on delayed type hypersensitivity (DTN) in mice has been studied. BCF of plasmid-containing virulent strains and non-plasmid avirulent strains have been found to suppress DTH to xenogenic splenocytes. Gel filtration data have shown that immunosuppressive factor possesses molecular weight about 180-800 kDa. BCF treated with etanol-ether mixture got to soluble fraction that evidenced for its lipid nature. This factor can be inactivated or reactivated by the treatment with trichloracetic acid, phenol and other chemicals. A new factor is found in reactivated BCF. It induces the ability of E. coli O55 to suppress DTH in mice and looks like Shigella factor. It is supposed that Klebsiella immunosuppressive factors are connected with lipopolysaccharide.

[The characteristics of the body's functional status and the state of the health of pupils in mining trade schools in an industrial zone]

The article presents results of study into the level of physical development, condition of the cardiovascular-, respiratory-, central nervous systems, immunobiologic resistance of the organism, prevalence of morphofunctional deviations from the norm, and morbidity rates among the students of the mining-trade secondary school (aged 15-18). It has been found out that adverse ecological situation in urban centres of the Donetsk Province together with specific character of training for occupation in coal industry have a marked negative effect on the functional status as well as health status of the adolescents. On the basis of the studies made a complex of measures has been designed to maintain and promote the health of students of the mining-trade secondary schools.

Influence of inheritance and fostering on sensitivity to effects of morphine on nociception and locomotor activity in two inbred rat strains

There are differences between individuals in their pain threshold, locomotor activity, and sensitivity to drugs of abuse which affect these processes. We have investigated the role of genetic differences and fostering in determining sensitivity to the action of morphine on nociception and locomotor activity in two strains of rats [Fischer-344 (F) and WAG/G (W)], using methods of reciprocal cross and cross-fostering. Nine-week old rats were used in the experiments. It was found that FF rats were more sensitive to the action of morphine on locomotor activity in open field apparatus than WW rats. Both types of F1 hybrids inherited a low sensitivity to the depressive action of morphine, their activity significantly differed from FF activity and had no distinction from that of WW rats. However, there was a strong maternal effect: if WW rats were fostered by a FF mother, the depression of their locomotor activity was similar to that of FF inbred rats, and vice versa. There were significant differences between normal and cross-fostered rats in all groups. WW rats had a higher sensitivity to thermal stimuli than FF rats. Both types of hybrids had intermediate nociceptive latencies. The strain difference between WW and FF rats in the baseline latencies of tail withdrawal disappeared after crossfostering-the latencies in FF rats were significantly decreased. Administration of morphine produced greater antinociception in FF rats than in WW. Cross-fostering of FF rats by WW mothers dramatically decreased their sensitivity to the analgesic action of morphine, while WW rats fostered by FF mothers did not change their resistance to morphine induced antinociception. Thus, the sensitivity of young rats to morphine-induced analgesia or depression of locomotor activity is mostly determined by fostering during the first 21 days.

[The modulating effect of the thyrotropin-releasing hormone on genetically induced mechanisms of morphine sensitivity]

The influence of thyrotropin-releasing hormone (TRH) on morphine-induced analgesic and reinforced responses was studied in two inbred strains of rats, Fischer-344 (F344) and Wistar Albino Glaxo/GSto (WAG). Conditioned place preference, voluntary consumption of morphine solution and analgesic action of morphine in tail immersion test were studied. There were interstrain differences in pain sensitivity, i.e., F344 rats had longer latency of tail immersion and deeper analgesic effect of morphine (5 mg/kg, ip) than WAG rats. TRH (1 mg/kg, ip) produced a stronger analgesic effect in WAG rats, while F344 rats demonstrated only slight increase in pain threshold. Administration of TRH in combination with morphine significantly stronger potentiated the effect of the latter in WAG than in F344 rats. F344 rats preferred morphine in the two-bottle choice test and consumed relatively larger amount of morphine solution in the drinking paradigm than WAG rats. Morphine in the dose of 5 mg/kg (ip) induced place preference in both rat strains. Intraventricular administration of TRH (1 mcg) produced a slight effect of place preference only in F344 rats. Preceded by morphine, such injection reduced the effect of place preference. It is suggested that WAG and F344 rats have different sensitivity of brain structures to TRH. This is probably determined by genetic differences in dissociation of analgesic and reinforcing effects of morphine.

[The genetic characteristics of the analgesic action of substance P, bradykinin and thyroliberin in the rats of 2 inbred strains]

A participation of nonopiate peptide brain systems in the mechanism of individual pain sensation was studied. The experiments were carried out on rats of two inbred strains, Fischer-344 and WAG/G, which exhibit different threshold of thermal pain sensation. The action of nonopiate oligopeptides (substance P, bradykinin, and thiroliberin) on the latent period of tail immersion from hot water was studied. It was found that significant analgesic action of substance P, bradykinin, and thiroliberin is more pronounced in rats more sensitive to thermal stimuli (WAG/G). The rats with reduced thermal sensitivity (Fischer-344) are shown to be insensitive to analgesic action of substance P, bradykinin, and thiroliberin.

[The immunosuppressive activity of Streptococcus aureus peptidoglycan]

The immunosuppressive activity of peptidoglycan, obtained from S. aureus was studied in mouse experiments on the model of delayed hypersensitivity (DH) to guinea pig antigens. The study revealed that PG suppressed DH, this action being linked with its insoluble fraction. The soluble part of PG did not suppress DH. Experiments with the use of immunosorbent demonstrated the existence of serological similarity between the active factor of the soluble part of PG and its insoluble part.

[The effect of shigellae on delayed hypersensitivity in mice infected by different routes]

The influence of virulent and avirulent shigellae on delayed hypersensitivity in the case of infection by different methods has been examined. It was found that the stimulating effect of avirulent shigellae and suppressive effect of virulent shigellae were displayed after intranasal infection. Intraperitoneal and intravenous infection was accompanied by only immunosuppressive influence, which was displayed by the virulent bacteria. The discrimination of T-suppressors by low doses of cyclophosphamide did not abolish the suppressive effect of shigellae. At the same time immunosuppressive factor of spleen was produced equally after infection by different-virulence shigellae. A conclusion was drawn that T-suppressors and immunosuppressive spleen factor did not take part in the mechanism of shigellae immunosuppression.

[A method for the quantitative assessment of the withdrawal syndrome in morphine-dependent rats]

The evaluation of strength of morphine withdrawal syndrome in rats after the 17th day i. p. morphine administration is proposed as calculation of individual indexes in "open field" test. It is found, that injection 1, 5 or 10 mg/kg of morphine 30 min before testing, decreases the withdrawal syndrome in dose dependent manner. Disappearance of particular withdrawal signs took place in different doses of morphine pretreatment. According to this effect all the signs were divided into four groups and signs of each group were given by the specificity coefficient (from 0 to 3). The total individual index of the withdrawal syndrome was calculated as a sum of particular signs, multiplied by the particular coefficient. Specificity of significant signs decrease according to the order: "wet dog" shakes, diarrhea, writhings, dyspnea, paw shakes, ptosis, piloerection and teeth chattering.

[The inhibition of the cellular immune response by Pseudomonas aeruginosa extracts]

Aquatic-phenol trichloroacetic and salt extracts of Pseudomonas aeruginosa have been studied for their effect on hypersensitivity of the delayed type to guinea pig antigen in mice. It is found that salt extracts of wild strains contain thermostable immunosuppressive factors which are of the lipid nature, have high molecular weight and can be inactivated by trichloroacetic acid and phenol. The salt extracts of museum strains as well as aquatic-phenol and trichloroacetic extracts obtained from wild and museum strains had no immunosuppressive activity.

[The participation of neuropeptide Y and the catecholaminergic systems of the brain in feeding behavior]

Following intracerebroventricular (icv) administration of the lowest doses (100 ng) of neuropeptide Y (NPY) the feeding behaviour was suppressed, while higher doses (5 mcg) of NPY enhanced it. Prazosin (9.5 nmol, icv), a selective alpha 1-adrenoceptor antagonist, attenuated the stimulatory effect of 5 mcg NPY on food intake. Yohimbine (15 nmol, icv) and propranolol (5 mg/kg, ip) had no effect on NPY-induced feeding behaviour. Naloxone inhibited NPY-induced feeding behaviour and did not influence on the NPY-induced suppression of food intake. These data give evidence for heterogeneity among the central NPY receptors. The effect of NPY on feeding behaviour may, at least in part, be mediated via alpha 1-adrenoceptors.

Differences in morphine reinforcement property in two inbred rat strains: associations with cortical receptors, behavioral activity, analgesia and the cataleptic effects of morphine

The purpose of the current study was to investigate genetic differences between two inbred strains of rats, Fisher-344 (F344/N) and Wistar Albino Glaxo (WAG/GSto), in a number of drug-naive and drug-related behaviors, including oral and intravenous morphine self-administration. F344/N and WAG/GSto rats differed in drug-naive behaviors such as nociception, rearing and sensitivity to lick suppression tests but did not differ in locomotor activity, ambulation or grooming behavior. F344/N rats were less sensitive to thermal stimuli as measured via tail-flick response, and more sensitive to the suppressive effects of intermittent shock in a lick suppression test. The F344/N rats demonstrated a significantly greater amount of rearing in open field tests but did not differ from WAG/GSto rats in locomotor activity, ambulation or grooming behavior. In addition to the behavioral results, naive F344/N and WAG/GSto rats were found to differ in mu and alpha 2 receptor concentrations (F344/N > WAG/GSto) and in 5HT2 and D2 affinity constants (WAG/GSto > F344/N). These two inbred rat strains also differed in drug-related behaviors. F344/N rats showed significantly greater depression of locomotor activity at morphine 3 mg/kg than WAG/GSto rats. In addition, F344/N rats consumed significantly greater amounts of morphine in a two-bottle choice procedure and morphine maintained significantly greater amounts of behavior during intravenous self-administration sessions. Importantly, drug maintained behavior was significantly greater than with vehicle only in the F344/N rats during operant self-administration sessions.

[Antibody formation to morphine and neuromediators in morphinized rats]

The paper demonstrates induction of antibodies to morphine and neurotransmitters (dopamine, norepinephrine, serotonin) in rats treated with intraperitoneal injections of morphine hydrochloride during 2 and 4 weeks in increasing doses. A contribution of such antibodies to the mechanisms of morphine tolerance and formation of physical dependence is considered.

[Differences in the characteristics of opiate and catecholaminergic receptors of the striatum and cerebral cortex of rats of Fisher-344 and WAG/GSto strains may cause differences in reinforced action of morphine]

It has been shown that Fischer-344 rats more than WAG/GSto inbred rats preferred to consume the solution of morphine. In intravenous self-administration testing, Fischer-344 rats had a higher rate of reinforced responses that resulted in morphine infusion. Bmax values for mu- and alpha 2-adrenoreceptors were significantly higher in the cortex of WAG/GSto rats. The sensitivity of the serotonin and dopamine receptors in the cortex and striatum of WAG/GSto rats was lower than that in Fischer-344 rats. These findings suggest that the difference between morphine consumptions in two inbred rat strains may be due to individual genetic patterns determining opioid and catecholamine receptors binding in the brain.

Biochemical resistance to development of morphine-dependence in rats: biogenic amines, its receptors and antibodies

The level of norepinephrine (NE), epinephrine (E) and dopamine (DA) in hypothalamus and blood plasma along with antibodies to NE, DA and serotonin (5-HT) and characteristics of alpha 1-, alpha 2-adrenergic, D2-dopaminergic and S2-serotoninergic receptors in synaptic brain membranes were studied in two groups of rats predisposed or resistant to the formation of physical morphine dependence. The resistant animals were characterized by a significant elevation of DA levels in blood plasma, elevation of antibodies to NE, and by higher concentration of alpha 2-adrenergic receptors in the brain cortex and of D2-receptors in striatum. The affinity of D2-receptors to dopamine in resistant rats also was higher than in predisposed animals. The other parameters studied did not differ significantly between the two groups. These findings suggest that the increased activity of DA and NE neurotransmitter systems can be a cause for the genetic resistance of some individuals among Wistar rats to the formation of physical dependence on morphine.