The social cognition of medical knowledge, with special reference to childhood epilepsy

This paper arose out of an engagement in medical communication courses at a Gulf university. It deploys a theoretical framework derived from a (critical) sociocognitive approach to discourse analysis in order to investigate three aspects of medical discourse relating to childhood epilepsy: the cognitive processes that are entailed in relating different types of medical knowledge to their communicative context; the types of medical knowledge that are constituted in the three different text types analysed; and the relationship between these different types of medical knowledge and the discursive features of each text type. The paper argues that there is a cognitive dimension to the human experience of understanding and talking about one specialized from of medical knowledge. It recommends that texts be studied in medical communication courses not just in terms of their discrete formal features but also critically, in terms of the knowledge which they produce, transmit and reproduce

The modified 2VO ischemia protocol causes cognitive impairment similar to that induced by the standard method, but with a better survival rate

Permanent bilateral occlusion of the common carotid arteries (2VO) in the rat has been established as a valid experimental model to investigate the effects of chronic cerebral hypoperfusion on cognitive function and neurodegenerative processes. Our aim was to compare the cognitive and morphological outcomes following the standard 2VO procedure, in which there is concomitant artery ligation, with those of a modified protocol, with a 1-week interval between artery occlusions to avoid an abrupt reduction of cerebral blood flow, as assessed by animal performance in the water maze and damage extension to the hippocampus and striatum. Male Wistar rats (N = 47) aged 3 months were subjected to chronic hypoperfusion by permanent bilateral ligation of the common carotid arteries using either the standard or the modified protocol, with the right carotid being the first to be occluded. Three months after the surgical procedure, rat performance in the water maze was assessed to investigate long-term effects on spatial learning and memory and their brains were processed in order to estimate hippocampal volume and striatal area. Both groups of hypoperfused rats showed deficits in reference (F(8,172) = 7.0951, P < 0.00001) and working spatial memory [2nd (F(2,44) = 7.6884, P < 0.001), 3rd (F(2,44) = 21.481, P < 0.00001) and 4th trials (F(2,44) = 28.620, P < 0.0001)]; however, no evidence of tissue atrophy was found in the brain structures studied. Despite similar behavioral and morphological outcomes, the rats submitted to the modified protocol showed a significant increase in survival rate, during the 3 months of the experiment (P < 0.02)

A study on immunotoxicological effects of subacute amitraz exposure in rats

The effects of amitraz, a formamidine pesticide, were investigated in four-week old outbred male Wistar rats on certain classic toxicological and haematological parameters as well as on specific immune functions. The animals were treated, per os by gavage for 28 days, in a five-day treatment two days break system, with 26.5, 21.1, 10.6 and 5.29 mg/kg/day amitraz. On the 29th day, organ weights of the thymus, heart, lung, spleen, liver, kidneys, adrenals, testicles and popliteal lymph node; WBC and RBC counts, Ht, MCV, haemoglobin; and cell content of the femoral bone marrow were determined. In two separate groups, the effects of amitraz on the PFC content of the spleen, and on the maximum level and time course of DTH reaction, were investigated. Amitraz in 26.5 mg/kg dose increased relative adrenal weight, and decreased relative liver weight, MCV value, PFC content of the spleen, and the maximum level of DTH reaction. The 21.1 mg/kg dose decreased only MCV value, while 10.6 mg/kg elevated the liver-to-brain weight ratio. Based of these findings, a NOEL dose of 5.29 mg/kg was determined for amitraz in this experimental system; while the LOEL doses were 10.6 mg/kg for the general toxicological, 21.1 mg/kg for the haematological and 26.5 mg/kg for the immune function parameters. The results show that the exposure sensitivity of these immune functions to amitraz is lower than that of some other toxicological and haematological parameters