Medical hypotheses
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The prevalence of autism, a neurodevelopmental condition resulting from genetic and environmental causes, has increased dramatically during the last decade. Among the potential environmental factors, hyperserotonemia during pregnancy and its effect on brain development could be playing a role in this prevalence raise. In the rodent model developed by Whitaker-Azmitia and colleagues, hyperserotonemia during fetal development results in a dysfunction of the hypothalamo-pituitary axis, affecting the amygdala as well as pro-social hormone oxytocin regulation. ⋯ Selective serotonin reuptake inhibitors (SSRI) are the most widely used class of antidepressants drugs, and they are not contraindicated during pregnancy. In this paper, we hypothesize that increased serotonemia during pregnancy, including due to SSRI intake, could be one of the causes of the raising prevalence in autism. If our hypothesis is confirmed, it will not only shed light on one of the possible reason for autism prevalence, but also offer new preventive and treatment options.
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Postoperative cognitive dysfunction (POCD) which is a decline in cognitive function after surgery can present days to weeks after surgery and may remain a permanent disorder. The exact pathophysiological mechanism of POCD is still unknown. In view the incidence of POCD does not seem to be influenced by the depth and the type of anesthesia, many investigators believe that inflammatory response plays a key role in the pathogenesis of POCD. ⋯ We hypothesize that inflammatory response is the initial factor of the occurrence and development of POCD and AD. Neuroinflammatory response associates with POCD and AD. The effective pathway to prevention and therapy of POCD and AD should consider measures against inflammatory response, especially against neuroinflammatory response.
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The majority of professional scientists make use of the artefacts of science but lack understanding of what these mean; raising the question: has the tradition of science been broken? Explicit knowledge is only a selective summary but practical capability derives from implicit, traditional or 'tacit' knowledge that is handed on between- and across-generations by slow, assimilative processes requiring extended human contact through a wide range of situations. This was achieved mainly by prolonged apprenticeship to a Master. Such methods recognize the gulf between being able to do something and knowing how you have done it; and the further gap between knowing how you have done something and being able to teach it by explicit instructions. ⋯ Most of modern science is therefore apparently in the post-holocaust situation described in A canticle for Liebowitz and After Virtue, but the catastrophe was bureaucratic, rather than violent. So, the tradition has indeed been broken. However, for as long as the fact is known that the tradition has been broken, and living representatives of the tradition are still alive and active, there still exists a remote possibility that the tradition could be revived.
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Humans are an unusual species because they exhibit an economic division of labour. Most theories concerning the evolution of specifically human intelligence have focused either on economic problems or sexual selection mechanisms, both of which apply more to men than women. Yet while there is evidence for men having a slightly higher average IQ, the sexual dimorphism of intelligence is not obvious (except at unusually high and low levels). ⋯ However, the effect of maternal IQ on child mortality would probably only be of major evolutionary significance in environments where childhood mortality rates were high. The modern situation is that population growth is determined mostly by birth rates; so in modern conditions, maternal intelligence may no longer have a significant effect on reproductive success; the effect of female IQ on reproductive success is often negative. Nonetheless, in the past it is plausible that the link between maternal IQ and child survival constituted a strong selection pressure acting specifically on women.