Cued memory reconsolidation in rats requires nitric oxide

It is well‐known that the reactivation of consolidated fear memory under boundary conditions of novelty and protein synthesis blockade results in an impairment of memory, suggesting that the reactivated memory is destabilized and requires synthesis of new proteins for reconsolidation. We tested the hypothesis of nitric oxide (NO) involvement in memory destabilization during the reconsolidation process in rats using memory reactivation under different conditions. We report that administration of NO‐synthase selective blockers 3‐Br‐7‐NI or ARL in the conditions of reactivation of memory under a protein synthesis blockade prevented destabilization of fear memory to the conditioned stimulus. Obtained results support the role of NO signaling pathway in the destabilization of existing fear memory triggered by reactivation, and demonstrate that the disruption of this pathway during memory reconsolidation may prevent changes in long‐term memory.     

Prognostic value of functional methods of the study of respiration and blood circulation in surgery of tuberculous spondylitis

Prognostic value of the basic indices of the external respiration function and central hemodynamics in view of predicting the nature of an early postoperative period in tuberculous spondylitis patients is demonstrated. Such indices, as vital capacity, ventilation and hemodynamic supply indices, and mean pressure in the pulmonary artery have the greatest prognostic value. One-dimensional analysis of variance of the functional examination data obtained from 209 patients with tuberculous spondylitis was used in this study.     

Causes of ineffectiveness of BCG vaccination and its impact on childhood tuberculosis

In the last few years BCG vaccination has covered 97% of the newborns, but in 45% of them this vaccination proves to be low effective since no more than 2- or 3-mm long postvaccination cicatrix disappears by the 2-nd or 3-d year of their lives. The reasons of a low efficacy of BCG vaccination include inadequate BCG vaccination techniques, incomplete administration of the inoculation dose, etc. Cases of M. tuberculosis infection in children ineffectively vaccinated with BCG are 3 times more than among those effectively vaccinated and having postvaccination cicatrix.     

Pharmacokinetics and bioavailability of the new drug protecor upon peroral administration in rabbits and beagle dogs

A new high-performance liquid chromatographic method with ultraviolet detection has been used to determine the levels of the new cardiotropic drug protecor in the blood of animals (chincilla rabbits, 2.2 ± 0.2 kg; and beagle dogs, 10 ± 0.5 kg). The parameters of protecor pharmacokinetics and bioavailability upon peroral administration of protecor tablets have been determined. Rabbits showed effective absorption of the drug uupon peroral administration in a single dose (100 mg/kg) with a peak concentration in the plasma (C _max= 41 μg/mL) reached within T _max= 3 h followed by rapid removal of the drug from the organism with a half-elimination time T _/12β=1.71 h. Peroral administration of protecor in a single dose (50 mg/kg) in beagle dogs was characterized by C _max= 34.6 μg/mL, T _max = 3 h, and T _/12β=0.75 h. The bioavailability of protecor upon peroral administration was estimated at 90% (rabbits) and 80.7% (beagle dogs). __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 12, pp. 3–6, December, 2007.     

The effect of heat exposure on cortisol and catecholamine excretion rates in workers in glass manufacturing unit

The aim of the investigation was to study the effect of long term repeated heat exposure on the excretion rates of stress hormones of workers in glass manufacturing unit. Sixteen operators, exposed to heat, were studied during the hot period and compared to a control group of 16 subjects, working in the same manufacturing unit. Both groups had moderate work load. The microclimate components and the Wet Bulb Globe Temperature were used for defining the heat exposure. The excretion rates of cortisol, adrenaline and noradrenaline were followed during the early morning shifts on three hour intervals using RIA and fluoriphotometric methods. Heart rate was followed, too. The psychosocial factors were measured by the "My job" questionnaire. Highly significantly higher cortisol, noradrenaline and adrenaline values were measured in the heat exposed operators compared to the control group, while significant differences of the psychosocial factors between the two groups lacked. Even if the heart rate was in the safe limits, the found alterations in the stress system are considerable and indicate heat stress. The work in conditions of overheat is associated with considerable heat stress and the possible health implications need to be clarified.     

Alternative splicing of cGMP-dependent protein kinase I in angiotensin-hypertension: novel mechanism for nitrate tolerance in vascular smooth muscle

Nitrate tolerance (NT) in hypertension is attributed to reduced activity of soluble guanylyl cyclase (sGC). We examined NT in basilar artery vascular smooth muscle cells (VSMCs) from control rats, rats infused with angiotensin II (Ang; 240 microg/kg per hour for 4 days), which were normotensive, and Ang-hypertensive rats (AHR; 240 microg/kg per hour for 28 days). Ca2+-activated K+ (Maxi-K) channels in VSMCs from AHR showed reduced activation by NO donor, consistent with NT. The concentration-response relationship for 8-Br-cGMP was shifted 2.5-fold to the right, indicating that abnormal sGC alone could not account for NT. Inside-out patches from AHR showed normal activation with exogenous cGMP-dependent protein kinase I (cGKI), suggesting no abnormality downstream of cGKI. We hypothesized that the reduction in apparent affinity of 8-Br-cGMP for cGKI in AHR might be due to a change in relative amounts of cGKIalpha versus cGKIbeta, since cGKIbeta is less sensitive to cGMP activators than cGKIalpha. This was substantiated by showing the following in AHR: (1) reduced effect of the cGKIalpha-selective activator 8-APT-cGMP; (2) reduced total cGKI protein (both isoforms), but an increase in cGKIbeta protein in quantitative immunofluorescence and Western blots; (3) similar changes in cGKI isoforms immunoisolated with Maxi-K channels; and (4) a large increase in cGKIbeta mRNA and a decrease in cGKIalpha mRNA in real-time PCR and Northern blots. Upregulation of cytosolic cGKIbeta was evident 4 days after Ang infusion, before development of hypertension. Our data identify a functional role for cGKIbeta in VSMCs previously ascribed exclusively to cGKIalpha. Ang-induced alternative splicing of cGKI represents a novel mechanism for reducing sensitivity to NO/cGMP.     

Use of geoinformational systems for epidemiological studying malignant laryngeal neoplasms in Krasnoyarsk

This paper shows it possible to use geoinformational systems for mapping and analyzing medical statistical data on those with malignant laryngeal neoplasms. The fact that the distribution of the patients can be shown on the map of a town in relation to the location of their houses (if they have an address) allows differentiation of the ecological living conditions of these patients, which in turn makes it possible to put not only high morbidity areas on the map of a town, but also to consider the characteristics of the environment in these areas.     

Use of a three-component scheme of immunosuppression on morphologic and immunohistochemical changes of transplants in the early postoperative period

Three-component (cyclosporin A, corticosteroids and azathioprine) immunosuppression has been widely introduced in the treatment of recipients of renal transplants because it allows a significant reduction of the components' doses in greater effectiveness. The analysis of the results of 83 puncture biopsies obtained in the immediate postoperative period after kidney transplantation has shown that administration of an imidazole derivative allows raising therapeutic concentration of cyclosporin up to 200-300 ng/ml, thus preventing rejection crises. However, increased blood concentration of cyclosporin does not increase its toxicity as a result of a significant fall in the overall level of the metabolites.