Archives Italiennes De Biologie最新文献

We used electrocortical spectral analysis and fractal methods for assessing the effects of unilateral, single brain injury on cerebellum. Cerebellar electrocortical activity was recorded in control state (before the injury) and after a single brain injury of the cerebellar cortex in anesthetized rats. We noticed that the mean power in gamma high-frequency domain (32-128 Hz) of the cerebellum, was increased after the first brain injury, while after a two-week recovery, it was larger than before the injury. The unilateral brain injury induced a permanent increase of the mild gamma activity in both the left and the right side of cerebellum cortex, but there was no further increase after the lesion was repeated. Our recent electrophysiological study on the cerebellum (Culic et al., 2005) suggested that the mean power spectra of the cerebellar cortical activity in the gamma frequency range might be the indicator of acute single focal brain injury. However, there is insufficient information on the effects of the repeated brain injury on the cerebellar electrocortical activity and morphology. There was no significant difference between the absolute and the relative mean power of the left and the right paravermal cortical activity (before, as well as, after the injury), in each of the animals tested afterwards, but there were differences between the left and the right side of cerebellum in experimental animals. Repeated injury of the cerebellar cortical areas, is strengthened by morphological changes in the cerebellar hemisphere, and shows a decrease in delta and an increase in gamma range.

Aim of our study was to assess functional outcome measured by modified Rankin scale (mRS) in patients that were treated with thrombolytic therapy-recombinant tissue plasminogen activator (rtPA) after acute ischemic stroke. The study included 100 participants that were treated after acute ischemic stroke. Analyzed parameters included: gender; age groups: age 54 and below (Group_{up to-54}), 55-64 (Group_55-64), 65-74 (Group_65-74), and 75 and above (Group_75-up); cerebral blood flow (CBF) and cerebral blood volume (CBV). Considering time of rtPA administration, we analyzed 3 groups: between 1-2 hours from stroke onset (Time_1-2h), 2-3 hours (Time_2-3h) and 3-4.5 hours (Time_3h-up). NIHSS scores were analyzed: NIHSS 1-at admission and NIHSS 2-at discharge from hospital; and mRS values: RANKIN 1-at admission and RANKIN 2-at discharge from hospital. There is significant reduction in NIHSS and mRS scores between two measurements for all groups of evaluated parameters. CBF, CBV and NIHSS values at admission significantly correlated with mRS scores at admission (p<0.01), as well as with mRS scores at discharge except for CBF where statistical significance was (p=0.019). Significantly lower values of NIHSS at admission (p<0.01), CBF values (p<0.01) and CBV values (p<0.01) are noticed in the group with mRS≤2. Early induction of rtPA treatment in patients with acute ischemic stroke within first 4.5 hours significantly increases positive treatment outcome in both genders and for all evaluated age groups. Favorable outcome (mRS≤2) at the time of discharge from hospital is significantly associated with lower NIHSS values at admission.

We assessed the role of the Toll-like receptor 4 (TLR4) gene in the ventrolateral periaqueductal gray (vlPAG) region of morphine-dependent rats on attenuating withdrawal syndrome, and regulating glutamic acid decarboxylase (GAD67), glutamic acid (Glu), and gamma-aminobutyric acid (GABA). After siRNA-mediated downregulation of TLR4, changes were observed in withdrawal behavior and downstream signaling molecules. Rats were injected into the vlPAG with TLR4 siRNA, followed by intraperitoneal injection of morphine for 5 consecutive days, and then naloxone, and the behavioral indices of morphine withdrawal were observed. 'Wet-dog' shakes, teeth chattering, and the total scores of withdrawal reactions were reduced. TLR4 expression and Glu levels were reduced, whereas GAD67 and GABA levels were increased. Overall, these findings indicate that modifying TLR4 gene expression in the vlPAG stimulates expression of the downstream signaling molecule, GAD67, which decreases Glu levels and increases GABA levels. This mechanism may explain the inhibition of withdrawal syndrome in morphine-dependent rats.

We previously reported that in normotensive humans submaximal mouth opening (mandibular extension) obtained by an ad hoc dilator (spring device), associated with partial masticatory movements and prolonged for 10 minutes is followed by a long-lasting reduction of blood pressure (BP) and heart rate (HR). Similar results were obtained by us in anesthetized rats. A recent independent study failed to confirm the results in the normotensive human. We reassessed, in 25 normotensive volunteers, the effects on BP and HR of mandibular extension obtained by the spring device associated with partial masticatory movements compared to a control procedure, consisting in keeping a tongue depressor between the incisor teeth. Both procedures were applied for 10 minutes and systolic BP (SBP), diastolic BP (DBP) and HR were measured every 10 minutes by an automatic recorder, for 30 minutes before and 120 minutes after the procedures in seated subjects watching nature documentary films on laptop screen.Baseline levels (mean of the last 3 measurements before procedure) did not significantly differ between the experimental and control sessions. Two way repeated measures ANOVA on absolute (recorded) values did not reveal a significant main effect of treatment for SBP, DBP and HR, but a significant main effect of time (P<0.001) for BP and HR. In addition, a significant interaction of time and treatment was found for SBP (P<0.001) and DBP (P=0.005), but not for HR. In addition, two way repeated measures ANOVA was done on changes from baseline obtaining a significant main effect of treatment (P<0.001) and time (P<0.001) and a significant interaction of time and treatment for SBP (P<0.001) and DBP (P<0.01). Post-hoc comparisons revealed significantly lower values for SBP and DBP in experimental compared to control values at almost all times and this decrement was by about 5 mmHg. Furthermore, for both absolute values and changes from baseline, the interaction effect was, for BP, of a qualitative type as indicated by an opposite effect in the time-course between control and experimental sessions. This study thus provides confirmatory evidence that submaximal mouth opening for a relatively brief time is followed by prolonged albeit small reductions of BP in normotensive human volunteers.