ALTERATIONS OF LOCAL BLOOD FLOW IN THE PENUMBRA ZONE OF LOCAL CEREBRAL INFARCTION

The main objective of this study was to reveal the circulatory changes in the Penumbra zone of stroke, which was induced by the photochemical method in the cerebral cortex of the rats. It has been revealed that the maximum reduction in blood supply in the penumbra zone during permanent ischemia is achieved 24 hours after the completion of the process of inducing thrombosis of vessels. Therapeutic intervention to save the cells of the Penumbra zone, which are in the initial stages of apoptosis, it is advisable to carry out in the first 12 hours after the onset of stroke.The main objective of this study was to reveal the circulatory changes in the Penumbra zone of stroke, which was induced by the photochemical method in the cerebral cortex of the rats. It has been revealed that the maximum reduction in blood supply in the penumbra zone during permanent ischemia is achieved 24 hours after the completion of the process of inducing thrombosis of vessels. Therapeutic intervention to save the cells of the Penumbra zone, which are in the initial stages of apoptosis, it is advisable to carry out in the first 12 hours after the onset of stroke

The Effect of Severe Intraventricular Hemorrhage on the Biorhythms of Feeding in Premature Infants

Background: Suck-swallow rhythmicity and the integration of breathing into infant feeding are developmentally regulated. Neurological injury and breathing abnormalities can both impact feeding in preterm infants. Objective: To determine the effects of neurologic injury independent of effects of disordered breathing on feeding biorhythms in premature infants. Methods: Low-risk preterm infants (LRP), infants with Grade 3–4 Intraventricular Hemorrhage (IVH), those with bronchopulmonary dysplasia (BPD), and those with both BPD and IVH (BPD+IVH) were identified. Forty-seven infants, 32–42 weeks Postmenstrual Age (PMA) were evaluated on one or more occasions (131 studies). Of these, 39 infants (81 studies) were performed at \u3e35 weeks PMA. Coefficient of variation (COV) (=standard deviation of the inter-event (e.g., suck-suck, swallow-breath, etc.) interval divided by the mean of the interval) was used to quantify rhythmic stability. Results: To adjust for PMA, only those infants \u3e35–42 weeks were compared. Suck-suck COV was significantly lower (more rhythmically stable) in the LRP group [COV = 0.274 ± 0.051 (S.D.)] compared to all other groups (BPD = 0.325 ± 0.066; IVH = 0.342 ± 0.072; BPD + IVH = 0.314 ± 0.069; all p \u3c 0.05). Similarly, suck-swallow COV was significantly lower in LRP babies (0.360 ± 0.066) compared to the BPD group (0.475 ± 0.113) and the IVH cohort (0.428 ± 0.075) (p \u3c 0.05). The BPD+IVH group (0.424 ± 0.109), while higher, was not quite statistically significant. Conclusions: Severe IVH negatively impacts suck-suck and suck-swallow rhythms. The independent effect of neurological injury in the form of IVH on feeding rhythms suggests that quantitative analysis of feeding may reflect and predict neurological sequelae

Redox hydrogel-based bienzyme microelectrodes for amperometric monitoring of L-glutamate

Fabrication and characterization of amperometric bienzyme L-glutamate sensitive microelectrodes are the prerequisite for monitoring changes Of L-glutamate concentration at glutamate-secreting cell cultures. The design of the glutamate microelectrodes is based on incorporating L-glutamate oxidase and horseradish peroxidase into a redox-hydrogel containing PVI19-dmeOs as the redox mediator and immobilizing this system onto the surface of platinum microdisk electrodes using, a dip-coating procedure. For amperometric measurements Of L-glutamate, these redox hydrogel-based bienzyme microelectrodes can be operated at low working potentials (-50 mV vs. Ag/AgCl) decreasing the influence of electroactive interferants possibly present in biological samples. The L-glutamate microsensors are characterized by a good operation stability and sensitivity (0.038+/-0.005 mAM(-1)), a low detection limit (0.5 muM in a conventional amperometric set-up and 0.03 muM in a Faraday cage, defined as three times the signal-to-noise ratio), a linear range up to 50 muM and a response time of about 35 s. The glutamate biosensors have been applied for the direct measurement Of L-glutamate release (upon chemical stimulation) from a population of immortalized hippocampal neurons (HN10 cells) demonstrating the possibility to amperometrically monitor in-Situ L-glutamate secretion from these cells

Ductular reaction at the early terms of common bile duct ligation in the rats

Ductular reaction (DR) in bile duct ligated rats generally appears from 2nd day after biliary obstruction (BO). However, we show that increased amount of ductular profiles is evident already in 6 hours after BDL. The study aims to explain the origin of such an early DR in response to BO. Male Lewis rats were subjected to common bile duct ligation (CBDL) for 3, 6, 12 and 24 hours and sham operation. Liver samples were studied histologically, immunohistochemically (Ki67, pan-Cytokeratin /AE1 + AE3/ and OV-6) and by immunoblotting analyses. It appeared that number of ductular profiles increase in timerelated manner after BO. These ductular profiles are formed by biliary epitheliocyte-like cells; No mitotic activity was revealed. Part of hepatocytes reveals pan-Cytokeratin positivity on 12 and 24 hours after BO. Total cytokeratins content at 24 hours after CBDL was 37% higher in comparison with control data. The significant increase was observed for the cytokeratins with molecular weights: 61, 56 and 40 KDa. Thus, early DR after BDL is mediated by widening of the existed finest biliary ramifications and is not associated with proliferation activities. This DR is accompanied by differentiation of hepatocytes toward bile duct-like cells