Behavioral learning and skill acquisition during a natural yet novel biting task.

OBJECTIVE: To investigate the effect of short-term training on behavioral learning and skill acquisition during a natural yet novel biting task. METHODS: Thirty (18 women) healthy volunteers in the age range of 18-32 years were divided into a naive (n = 17) and expert (n = 13) groups based on the self-reported familiarity to perform a complex behavioral biting task. The volunteers participated in a single experimental session divided into three sets with three series, each with ten trials of a standardized biting task. The task was to position, split and retrieve a sunflower seed from its shell without crushing the seed. The two consecutive sets were separated by fifteen minutes of short-term training. During the short-term training, the participants repeatedly performed the biting task for about fifteen minutes. A five-point grading system was devised to determine the performance and video registrations were made to determine the duration of the task. RESULTS: There was a significant main effect of training on the task performance scores (P < .001). The performance scores of the naive group before training was significantly lower than all the sets of the expert group (P < .010). The performance scores of the naive group were also significantly better after training than before (P = .001). However, the expert group took significantly shorter time to complete the task than the naive group. CONCLUSION: The results of the present study show a significant effect of training on the performance of a complex behavioral biting task. Training resulted in improved performance scores and a subtle decrease in the duration of the task.

Adsorptive Depletion of Myeloid Lineage Leucocytes as Remission Induction Therapy in Patients with Ulcerative Colitis after Failure of First-Line Medications: Results from a Three-Year Real World, Clinical Practice.

BACKGROUND/AIMS: In patients with active ulcerative colitis (UC), pharmacologics, although initially effective in most patients, are associated with refractoriness, loss of response or unfavourable side effects as additional morbidity factors. Depletion of myeloid lineage leucocytes like the CD14(+)CD16(+) monocyte phenotype, which is a major source of tumour necrosis factor-α, by granulocyte/monocyte apheresis (GMA) if effective, is also known to be free from side effects. METHODS: In clinical practice setting, 77 consecutive patients with moderate to severe UC, who failed to respond to first-line medications received GMA with the Adacolumn as remission induction therapy. Patients who achieved remission were followed for 3 years. RESULTS: Among the 77 patients, 46.8% were corticosteroids-naïve, 26% corticosteroid-dependent and 27.3% corticosteroid-refractory. The overall clinical remission rate was 79.2%, and the overall mucosal healing (MH) rate according to the Mayo endoscopic subscore ≤1 was 58.5%. MH rates in corticosteroid-naïve, corticosteroid-dependent and corticosteroid-refractory subgroups were 70.8, 56.3, and 38.5%, respectively. The 3-year sustained clinical remission rates in corticosteroid-naïve, corticosteroid-dependent and corticosteroid-refractory subgroups were 83.3, 68.8, and 23.1%, respectively. CONCLUSION: Corticosteroid-naïve patients appeared to benefit the most from the Adacolumn GMA, and attain a favourable long-term clinical course. Accordingly, GMA should be a first-line therapy in this clinical setting.

Spatial memory extinction: a c-Fos protein mapping study.

While the neuronal basis of spatial memory consolidation has been thoroughly studied, the substrates mediating the process of extinction remain largely unknown. This study aimed to evaluate the functional contribution of selected brain regions during the extinction of a previously acquired spatial memory task in the Morris water maze. For that purpose, we used adult male Wistar rats trained in a spatial reference memory task. Learning-related changes in c-Fos inmunoreactive cells after training were evaluated in cortical and subcortical regions. Results show that removal of the hidden platform in the water maze induced extinction of the previously reinforced escape behavior after 16 trials, without spontaneous recovery 24h later. Extinction was related with significantly higher numbers of c-Fos positive nuclei in amygdala nuclei and prefrontal cortex. On the other hand, the lateral mammillary bodies showed higher number of c-Fos positive cells than the control group. Therefore, in contrast with the results obtained in studies of classical conditioning, we show the involvement of diencephalic structures mediating this kind of learning. In summary, our findings suggest that medial prefrontal cortex, the amygdala complex and diencephalic structures like the lateral mammillary nuclei are relevant for the extinction of spatial memory.

Comparative Assessment of Clinical Efficacy between the Naive and the Switching Group to Donepezil: 12 Months Prospective Study

OBJECTIVES: The purpose of this study was to compare the efficacy between switching patients with Alzheimer's disease (AD) from galantamine or rivastigmine to donepezil because they were not responding adequately, and naive patients with AD who initiated therapy with donepezil. METHODS: A total of 108 patients were recruited for this 52-week study. The effect of donepezil on cognitive function was measured using Alzheimer's Disease Assessment Scale-cognitive subscale-preliminary Korean version (ADAS-cog-K). Patients' activities of daily living using Seoul-Activities of Daily Living (S-ADL) and the Seoul-Instrumental Activities of Daily Living (S-IADL);behavioral symptoms using the Korean version Neuropsychiatric Inventory (K-NPI) were measured at baseline, 13-weeks, 26-weeks, 39-weeks and 52-weeks. We defined the responsive patients to donepezil at those who showed a cognitive improvement or no change during the first six-month clinical trial. RESULTS: 86 naive patients and 22 switching patients were enrolled in the study. 74 patients completed the study and 34 discontinued their treatment before week 52. There was no significant difference between two patient groups in demographic data, baseline characteristics and dementia severity except duration of illness. The total ADAS-cog-K scores were not significantly different from baseline after 52 weeks of treatment in both groups. Both groups demonstrated deterioration of S-ADL and S-IADL at 52 weeks. The NPI scores did not significantly change in both groups. Based on the operational criteria, 61.6% of the naive group and 54.5% of the switching group were responders to donepezil. CONCLUSION: The switching group had similar levels of efficacy with the naive group who initiated therapy with donepezil. These results suggest that patients not responding adequately to rivastigmine or galantamine may improve or stabilize after switching to donepezil and prior medication does not effect donepezil's efficacy.