Vesicular acetylcholine transporter knock-down mice are more susceptible to pilocarpine induced status epilepticus

The pilocarpine (PILO) animal model of Temporal Lobe Epilepsy (TLE) portrays the most common changes in hippocampal circuitry found in human TLE. The acute cholinergic insult induces status epilepticus (SE), which triggers an overwhelming set of plastic events that result on late spontaneous recurrent limbic seizures. It has been suggested that the cholinergic system plays an important role in the synchronization required for ictogenesis. We took advantage of a knock-down animal model for the vesicular acetylcholine transporter (VAChT KD) to investigate seizure genesis in a model of cholinergic dysfunction. We induced SE in VAChT KD and wild-type (WT) mice by a single intraperitoneal injection of PILO in order to evaluate susceptibility to seizures. Video-EEG recordings evaluated epileptiform activity and ictal behavior onset. The hypothesis tested is that innate cholinergic hypofunction could result in increased susceptibility to PILO. VAChT KD(HOM) mice showed shorter latency for the first epileptiform discharge and for the first seizure episode, when compared to other groups. The duration of these seizure episodes, however, were not statistically different among experimental groups. On the other hand, VAChT KD(HOM) had the shortest latency to isoelectric EEG, when compared to WT and KD(HET). Our results indicate that a reduction of brain VAChT protein to the levels found in VAChT KD(HOM) mice alters the epileptic response to PILO. Thus, fine-tuning modulation of cholinergic tone can affect the susceptibility of epileptic responses to pilocarpine.     

Inhibitory network interactions shape the auditory processing of natural communication signals in the songbird auditory forebrain

The role of GABA in the central processing of complex auditory signals is not fully understood. We have studied the involvement of GABA A-mediated inhibition in the processing of birdsong, a learned vocal communication signal requiring intact hearing for its development and maintenance. We focused on caudomedial nidopallium (NCM), an area analogous to parts of the mammalian auditory cortex with selective responses to birdsong. We present evidence that GABA A-mediated inhibition plays a pronounced role in NCM's auditory processing of birdsong. Using immunocytochemistry, we show that approximately half of NCM's neurons are GABAergic. Whole cell patch-clamp recordings in a slice preparation demonstrate that, at rest, spontaneously active GABAergic synapses inhibit excitatory inputs onto NCM neurons via GABA A receptors. Multi-electrode electrophysiological recordings in awake birds show that local blockade of GABA A-mediated inhibition in NCM markedly affects the temporal pattern of song-evoked responses in NCM without modifications in frequency tuning. Surprisingly, this blockade increases the phasic and largely suppresses the tonic response component, reflecting dynamic relationships of inhibitory networks that could include disinhibition. Thus processing of learned natural communication sounds in songbirds, and possibly other vocal learners, may depend on complex interactions of inhibitory networks.     

Treadmill training for ataxic patients: a single-subject experimental design

OBJECTIVE: To investigate changes in gait quality, balance and mobility associated with treadmill training for ataxic individuals. DESIGN: Single-subject ABA design. Baseline phases (A) lasted three weeks and intervention (B) lasted four weeks. SETTING: University rehabilitation clinic. SUBJECTS: A woman (25 years) and a man (53 years) with chronic ataxia due to head trauma. INTERVENTION: Three 20-minute treadmill training sessions each week with progression in velocity and step length. MAIN MEASURES: Rivermead Visual Gait Assessment, Timed Up and Go, time to complete a balance task, walking speed, cadence, and stride length assessments three times a week during the 10 weeks. Data were analysed with the celeration line technique and two standard deviation band. RESULTS: Both individuals demonstrated gains in all parameters over initial baseline and subsequent phases, with performance increases ranging from 26% to 233% when first and last assessments were compared. Significantly superior effects of treadmill training over baseline conditions on cadence were detected (P<0.05). Gains in walking speed were not significantly better during intervention, but intervention withdrawal produced deceleration of performance gains. Gains in Timed Up and Go, step length and balance were not consistent and were possibly caused by a learning effect of the association between repeated testing and treadmill training. Rivermead Visual Gait Assessment gains reached significance only for subject 2 (P<0.05), probably because of increased variability of performance of subject 1. Results suggest that the association between repeated testing and treadmill training might have been responsible for the observed gains in the two ataxic patients.     

Evaluation of physical activity habits in patients with posttraumatic stress disorder

OBJECTIVE: In this study, we present data from a survey that aimed to assess the physical activity habits of adult Brazilian patients with Posttraumatic Stress Disorder. METHOD: Fifty male and female patients with Posttraumatic Stress Disorder participated in this study. The mean age at onset was 37+/-12 years, and the mean time between diagnosis and follow-up was 3.6+/-4.2 years. RESULTS: Substantial changes in physical activity habits were observed following the onset of PTSD. While more than half of the patients participated in physical activities prior to Posttraumatic Stress Disorder onset, there was a significant reduction in their participation afterwards. The justifications for stopping physical activities or sport participation were lack of time and lack of motivation. DISCUSSION: Several studies have shown that physical exercise decreases reverts symptoms of psychiatric disorders such as depression, anxiety and social isolation. We could therefore hypothesize that patients with Posttraumatic Stress Disorder who exercise should experience the same benefits. CONCLUSION: Our findings demonstrated that patients with Posttraumatic Stress Disorder have low levels of participation in sports or physical activities.     

Oral mucositis in acute lymphoblastic leukaemia: analysis of 169 paediatric patients

Chemotherapy-induced oral mucositis is a frequent therapeutic challenge in cancer patients. The purpose of this retrospective study was to estimate the prevalence and risk factors of oral mucositis in 169 acute lymphoblastic leukaemia (ALL) patients treated according to different chemotherapeutic trials at the Darcy Vargas Children's Hospital from 1994 to 2005. Demographic data, clinical history, chemotherapeutic treatment and patients' follow-up were recorded. The association of oral mucositis with age, gender, leucocyte counts at diagnosis and treatment was assessed by the chi-squared test and multivariate regression analysis. Seventy-seven ALL patients (46%) developed oral mucositis during the treatment. Patient age (P = 0.33), gender (P = 0.08) and leucocyte counts at diagnosis (P = 0.34) showed no correlation with the occurrence of oral mucositis. Multivariate regression analysis showed a significant risk for oral mucositis (P = 0.009) for ALL patients treated according to the ALL-BFM-95 protocol. These results strongly suggest the greater stomatotoxic effect of the ALL-BFM-95 trial when compared with Brazilian trials. We concluded that chemotherapy-induced oral mucositis should be systematically analysed prospectively in specialized centres for ALL treatment to establish the degree of toxicity of chemotherapeutic drugs and to improve the quality of life of patients based on more effective therapeutic and prophylactic approaches for prevention of its occurrence.     

Psychoeducational group and bipolar affective disorder: a reflection on the asylum and psychosocial models

Bipolar Affective Disorder (BAD), known by its chronicity, complexity and high rates of morbidity and mortality, is one of the main causes of disability in the world. There is growing evidence that its path can be changed by psychotherapy approaches, such as psychoeducation, which improves one's social and occupational behavior and capacity to deal with stressful situations. This study is an experience report about a psychoeducational group for individuals with BAD and their relatives, which consisted on reflecting upon the components of the mental health practice paradigm. Reflecting upon the psychosocial and asylum ways regarding the conceptions of object and mode of work permitted to locate the group in a psychosocial manner, as knowledge and experience favor the autonomy of the individuals, who have more chances to face the difficulties that occur in their suffering-existence process.