Gallbladder volvulus, a rare cause of acute abdomen, a case report.

INTRODUCTION: The gallbladder volvulus is a rare surgical emergency and its defined as the rotation of the gallbladder on its mesentery along the axis of the cystic duct and cystic artery. Definitive diagnosis is usually made during surgery and a delay in treatment may result in a high mortality due to rupture of gall bladder and bile peritonitis. CASE PRESENTATION: We report the case of an 88-year-old woman who presented with an acute torsion of gall bladder, which was treated promptly after admission by laparoscopic cholecystectomy. DISCUSSION: Acute torsion of gall bladder is a rare disease. Its pathogenesis is not well known but postulated to be multifactorial. Two anatomic variants that predispose to gall bladder torsion have been described. Clinical presentation is not specific, with symptoms and biologic signs that mimic acute cholecystitis. This condition should be suspected in elderly women with uncertain diagnosis of acute cholecystitis or acute abdominal pain of unknown origin. CONCLUSION: Gallbladder volvulus is a rare life-threatening surgical emergency that requires emergency surgical treatment. Out- come is often favorable when early diagnosis and surgery are made.

Discovery of recurring behavioural sequences in Wistar rat social activity: Possible support to studies on Autism Spectrum Disorders.

This study was undertaken to investigate whether, in rat interactive activities, recurring sequences of behavioural events might be identified and how and to what extent each component of the pair is involved. To this aim, the multivariate temporal-pattern (t-pattern) analysis was applied to the social interactions of 9 pairs of male Wistar rats tested in open field. Interactive activities were classified into intra- and inter-subjects. Quantitative evaluations showed that intra-subject behavioural elements represented 62.37% and inter-subject ones 37.63% of the comprehensive behaviour. T-pattern analysis revealed the presence of 221 different t-patterns organized in four different categories: containing exclusively inter-subject elements; containing both inter- and intra-subject elements; consisting of rat 1 and rat 2 intra-subject elements and, finally, consisting of intra-subject elements carried out by one of the two subjects. Results show that the activity of two interacting Wistar rats is structured on the basis of several recurring temporal sequences. Moreover, social interactions appear to be expressed also by t-patterns where the behavioural elements are carried out by animals seemingly not interacting. A support of t-pattern analysis to studies on Autism Spectrum Disorders is proposed.

Quantitative modeling of perception and production of time intervals.

The accurate perception/production of durations in the seconds and minutes range is important in a number of everyday activities, but the lack of direct experimental evidence on the neural circuits that could be involved has precluded the detailed elucidation of the underlying physiological mechanisms. We show, using a basic biophysical model of a timekeeping system and experimental data on time intervals produced or estimated under different conditions, that experimental values, variability, and distributions can be quantitatively explained in terms of a background synaptic activity such as that generated by attention. The model provides a plausible neural substrate for encoding time intervals, and the findings suggest how it may interplay at the single neuron level with the attentional system, to elaborate a subjective representation of the elapsing time.

A model of the effects of cognitive load on the subjective estimation and production of time intervals.

How and where the brain calculates elapsing time is not known, and one or more internal pacemakers or others timekeeping systems have been suggested. Experiments have shown that the accuracy in estimating or producing time intervals depends on many factors and, in particular, both on the length of the intervals to be estimated and on the additional, and unrelated, cognitive load required during the task. The psychological 'attentional approach' is able to explain the experimental data in terms of perturbations of a cognitive timer. However, the basic biophysical mechanisms that could be involved at the single neuron level are still not clear. Here we propose a computational model suggesting how the process to focus the attention on a non-temporal task could alter the perception of time intervals as observed in the experiments. The model suggests that an attention-based excitatory and/or inhibitory background synaptic noise, impinging on the pacemaker circuit, could represent both qualitative and quantitative features of the cognitive load. These effects are predicted to be independent of the number, location or specific implementations of the internal timing systems.

Operational intelligence and school problems measured by Piagetian tasks and Rhode Island Pupil Identification Scale.

To explore the relations between operational intelligence rated on several Piagetian tasks and school learning problems identified by the Rhode Island Pupil Identification Scale by Novack, Bonaventura, and Merenda we assumed that Piagetian performances would allow predicting learning problems of first graders. 38 pupils were evaluated by three teachers, who were asked to complete the Rhode Island scale. Then the same children were individually given 8 Piagetian tests (including conservation and logical tasks) by an examiner who had no information about the pupils' other scores. Analysis showed that successful Piagetian performances were associated with ratings of successful schoolwork. Analysis of variance confirmed that difficulties in operational reasoning predict occurrence of learning problems. We concluded that operational intelligence and school learning in children are closely related.