Overlapping stimulation of subthalamic nucleus and dentato-rubro-thalamic tract in Parkinson's disease after deep brain stimulation.

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) reduces tremor, rigidity, and akinesia. According to the literature, the dentato-rubro-thalamic tract (DRTt) is verified target for DBS in essential tremor; however, its role in the treatment of Parkinson's disease is only vaguely described. The aim of our study was to identify the relationship between symptom alleviation in PD patients and the distance of the DBS electrode electric field (EF) to the DRTt. METHODS: A single-center retrospective analysis of patients (N = 30) with idiopathic Parkinson's disease (PD) who underwent DBS between November 2018 and January 2020 was performed. DRTt and STN were visualized using diffusion-weighted imaging (DWI) and tractography protocol of magnetic resonance (MR). The EF was calculated and compared with STN and course of DRTt. Evaluation of patients before and after surgery was performed with use of UPDRS-III scale. The association between distance from EF to DRTt and clinical outcomes was examined. To confirm the anatomical variation between DRTt and STN observed in tractography, white matter dissection was performed with the Klingler technique on ten human brains. RESULTS: Patients with EF overlapping STN and DRTt benefited from significant motor symptoms improvement. Anatomical findings confirmed the presence of population differences in variability of the DRTt course and were consistent with the DRTt visualized by MR. CONCLUSIONS: DRTt proximity to STN, the main target in PD DBS surgery, confirmed by DWI with tractography protocol of MR combined with proper predefined stimulation parameters may improve efficacy of DBS-STN.

Modeling nitrous oxide production by a denitrifying-enhanced biologically phosphorus removing (EBPR) activated sludge in the presence of different carbon sources and electron acceptors.

In this study, the IWA Activated Sludge Model No. 2d (ASM2d) was expanded to identify the most important mechanisms leading to the anoxic nitrous oxide (N2O) production in the combined nitrogen (N) and phosphorus (P) removal activated sludge systems. The new model adopted a three-stage denitrification concept and was evaluated against the measured data from one/two-phase batch experiments carried out with activated sludge withdrawn from a local, large-scale biological nutrient removal wastewater treatment plant. The experiments were focused on investigating the effects of different external carbon sources (acetate, ethanol) and electron acceptors (nitrite, nitrate) on the mechanisms of N2O production in enhanced biological P removal by polyphosphate accumulating organisms (PAOs) and external carbon-based denitrification by ordinary heterotrophic organisms (OHOs). The experimental results explicitly showed that N2O production was predominantly governed by the presence of nitrite in the reactor regardless of the examined carbon source and the ratio COD/N in the reactor. The model was capable of accurately predicting (with R2 > 0.9) the behavior of not only N2O-N, but also NO3-N, NO2-N, soluble COD, and PO4-P. The simulation results revealed that only OHOs were responsible for N2O production, whereas the present denitrifying PAOs reduced only nitrate to nitrite.

[The radioprotective action of suprofen]. / Radiozashchitnoe deistvie suprofena.

Suprofen is a new non-steroidal anti-inflammatory drug administered intragastrically 90 min before roentgen irradiation in a dose of 20 mg/kg and then daily for 10 days in a dose of 10 mg/kg exerts the radioprotective effect evaluated according to a 30-day survival rate and an average life expectancy of the deceased animals as well as according to a decrease of postirradiation leukopenia incidence. A single administration of suprofen following roentgen irradiation exerts no radioprotective effect. Suprofen was found to enhance the radioprotective action of cysteamine.

Interaction of bradykinin with dopaminergic receptors in the CNS.

The influence of bradykinin on the action of compounds affecting predominantly the dopaminergic receptor was studied in behavioral tests (Lat test and sterotypy) and biochemically (estimation of the level of biogenic amines--noradrenaline, dopamine and serotonin, and their metabolites--normetanephrine, homovanillic and 5-hydroxyindoleacetic acids in the brain tissue). Bradykinin potentiated the action of nialamide with L-dopa, dopamine, 1,3-dimethyl-5-aminoadamantane, apomorphine and noradrenaline. Spiroperidol abolished potentializing effect of bradykinin on the central action of nialamide with L-DOPA and of noradrenaline. In animals receiving spiroperidol with bradykinin psychostimulatory action of noradrenaline was also not observed. FLA-63--inhibitor of dopamine beta-hydroxylase--increased the potentializing effect of bradykinin on the central action of dopamine. Most significant biochemical changes between the group receiving nialamide alone and the group given nialamide together with bradykinin have been observed in corpus striatum, where the level of dopamine and its metabolite--homovanillic acid--increased. The results obtained point out that the potentiation of the central effects of catecholamines by kinins depends mainly on the interaction of this peptide with dopaminergic receptor.