Comparativein vitro study of the effect of contrast media on complement activity and eicosanoid content in rat blood

The study comparesin vitro effect of different contrast media on complement activity and eicosanoid content. Ionic agents (Bilignost>Iodamide>Triombrast>Hexabrix) exert pronounced complement-activating effect, while nonionic agents markedly increase blood content of arachidonic acid metabolites. The complement-activating effect of contrast media did not correlate with their ability to elevate blood content of prostaglandin F_2α and leukotrienes C₄ and B₄. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 6, pp. 637–640, June, 1998     

Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon

We have examined whether dietary polyamines influence the formation and initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in rat colon. Effects of a combination of dietary polyamines at three dose levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g; spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied in animals in two different experimental situations: animals treated with AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a specific inhibitor of endogenous polyamine synthesis. In both experimental situations, dietary polyamines enhanced the growth of ACF, expressed as the number of large ACF (foci with three or more aberrant crypts, ACF > or = 3), whereas the formation of ACF, expressed as the number of ACF, was apparently not altered. In animals treated with AOM alone, maximal growth enhancing effect on ACF was nearly obtained with the median level of dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of DFMO was counteracted by dietary polyamines in a dose- dependent manner, and it was abolished at the highest level of polyamines. In conclusion, it was demonstrated that dietary polyamines are able to enhance the growth of AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused inhibition of ACF growth, probably by compensating for the DFMO-reduced endogenous polyamine synthesis.      

Significance of molecular genetic and immunological techniques in risk groups and in children with tuberculosis

A total of 188 children and adolescents were examined. In all the children, blood Mycobacterium tuberculosis (MBT) DNA was determined by polymerase chain reaction (PCR) and MBT antigens (AG) and antibodies (AB) were by enzyme immunoassay. The studies have shown that it is expedient to concurrently determine MBT DNA and MBT AT in order to identify local forms of tuberculosis in children from risk groups. If the tests are positive, a comprehensive examination for tuberculosis is required; the presence of the syndrome of common disturbances is generally associated with tuberculous infection. When a local form of tuberculosis is excluded, preventive chemotherapy should be performed. Further negative tests for MBT DNA and lower MBT AT may be a criterion for the efficiency of preventive treatment. In children with tuberculosis, the results of repeated blood and urine tests for MBT DNA provide a way of evaluating the course of a tuberculous process and the efficiency of chemotherapy. PCR used to determine blood and urine MBT DNA is a highly specific test as positive results were in 79% of the children with tuberculosis.     

Massive pulmonary artery thromboembolism after removal of sphenoid wing meningioma (clinical case with good outcome)

The paper describes a clinical case of the severe potentially fatal postoperative complication--massive pulmonary thromboembolism--in a patient after uncomplicated removal of meningioma of the wing of os basilare. It also describes the problems in the diagnosis, treatment, prevention of perioperative deep venous thrombosis of the shin and subsequent pulmonary thromboembolism in neurosurgery patients.     

Correlation between the results of glucocorticoid therapy and in vitro effect of glucocorticoids on monocytes in asthma

The effects of glucocorticoids on monocyte morphology and function in vitro and the results of high-dose budesonide therapy in patients with non-severe bronchial asthma were analyzed. Before therapy with inhalation glucocorticosteroid (budesonide) characteristics of blood monocytes and the effects of different concentrations of prednisolone on these cells were studied in vitro by luminol-dependent chemiluminescence and computer-assisted phase-interference microscopy. High sensitivity of patients to budesonide was associated with pronounced in vitro inhibitory effect of prednisolone on monocyte activity, which was not observed in cases with delayed effects of therapy. Pronounced inhibitory effects of glucocorticoids on monocytes in vitro were observed in patients both resistant and highly sensitive to glucocorticoid therapy. Hence, the resistance of patients with non-severe asthma to high-dose budesonide therapy is not related to the weakening of the inhibitory effect of glucocorticoids on monocyte activity.     

Developmental exposure to chlorpyrifos alters reactivity to environmental and social cues in adolescent mice

Neonatal mice were treated daily on postnatal days (pnds) 1 through 4 or 11 through 14 with the organophosphate pesticide chlorpyrifos (CPF), at doses (1 or 3 mg/kg) that do not evoke systemic toxicity. Brain acetylcholinesterase (AChE) activity was evaluated within 24 h from termination of treatments. Pups treated on pnds 1-4 underwent ultrasonic vocalization tests (pnds 5, 8, and 11) and a homing test (orientation to home nest material, pnd 10). Pups in both treatment schedules were then assessed for locomotor activity (pnd 25), novelty-seeking response (pnd 35), social interactions with an unfamiliar conspecific (pnd 45), and passive avoidance learning (pnd 60). AChE activity was reduced by 25% after CPF 1-4 but not after CPF 11-14 treatment. CPF selectively affected only the G(4) (tetramer) molecular isoform of AChE. Behavioral analysis showed that early CPF treatment failed to affect neonatal behaviors. Locomotor activity on pnd 25 was increased in 11-14 CPF-treated mice at both doses, and CPF-treated animals in both treatment schedules were more active when exposed to environmental novelty in the novelty-seeking test. All CPF-treated mice displayed more agonistic responses, and such effect was more marked in male mice exposed to the low CPF dose on pnds 11-14. Passive avoidance learning was not affected by CPF. These data indicate that developmental exposure to CPF induces long-term behavioral alterations in the mouse species and support the involvement of neural systems in addition to the cholinergic system in the delayed behavioral toxicity of CPF.     

Venous thromboses and pulmonary arterial thromboembolism in neurosurgical patients

The paper gives the results of a study conducted in 3 groups of neurosurgical patients in the analysis of autoptic material over 15 years in order to detect pulmonary arterial thromboembolism (PATE) as a cause of postoperative death in neurosurgical patients. In the latter, the incidence of PATE was ascertained to be 5.4%, as evidenced by autopsy and the distribution of the onset of a fatal outcome was biphasic. The informative value of determination of the blood level of fibrin D-dimer was analyzed in neurosurgical patients as a screening method for diagnosing prethrombosis. The method has shown to be of high informative value (about 90% sensitivity) and may be used in clinical practice. The effectiveness and safety of the combined procedure of preventing venous thromboembolic events (mechanical method with a subsequent switching over to pharmacological methods on days 3) were evaluated. The method has proven to be effective and safe.     

Capacity of birds for transitive inference: The solution of the gillan test by corvids and pigeons

A system of four to five differentiations forming a series, in which the magnitude of the reinforcement (R) of each succeeding color stimulus was greater than the preceding by one unit, was formed in pigeons (Columba livia L.) and crows (Corvus corone cornix L.). The number of units of the R that was associated with each of the stimuli increased successively from stimulus pair to stimulus pair from one up to four to five (1st series) and from five to ten (2nd series). After the development of the system of differentiations, the capacity of the birds to compare the magnitudes of R in given new combinations of stimuli and to choose the stimulus associated with the greater R (transitive inference) was tested. Given small Rs, the pigeons and crows solved the test equally successfully; in the case of large reinforcements, the pigeons began to make random choices, while in the crows the proportion of correct choices decreased. The proportion of appropriate solutions was greater when it was a greater absolute difference between the number of units of the R to be compared. The solution of the test employed by the birds is not proof of their capacity for transitive inference, since it can be explained by their capacity for unexpected comparison of the absolute values of the R associated with each of the stimuli. Department of Higher Nervous Activity, M. V. Lomonosov Moscow State University. Institute of Pharmacology, Russian Academy of Medical Sciences, Moscow. Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 45, No. 4, pp. 716–722, July–August, 1995.     

Melanocytes of arteries of the human optic nerve]

The melanocytes of the arteries feeding the optic nerve were studied by electron microscopy and methods developed by Koelle, Furness and Costa. The regularities of melanocyte distribution in vessel walls, their polymorphism and ultrastructure were investigated. The results demonstrate the interrelationships between pigmented cells and the adrenergic and cholinergic nervous system of the arteries. The authors discuss the possible role of melanocytes in local regulation of ophthalmic tone and in the formation of local neuroendocrine system.