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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Galaburda et al. (1987) have suggested that asymmetry of planum temporale in men would result from an asymmetrical neuronal loss; symmetry would implicate a failure of asymmetrical cell loss. There are several reports indicating a similarity between men and animal in cerebral lateralization. In the present work, a morphological analysis was performed in sylvian fissure (SF) of cats. Asymmetry coefficients (AC) were distributed symmetrically and normally with a mean of zero. However, female cats exhibited a relatively stronger leftward asymmetry (left SF > right SF), and male cats a relatively stronger rightward asymmetry in SF. The results generally supported those of Galaburda and his coworkers. Deviations from their results depended mainly on paw preference. The similarity between human brain and animal brain was accentuated once more concerning cerebral lateralization. The results were not appropriate to conclude about the mechanisms of cerebral lateralization. Testosterone in males and estrogen in females were suggested to be the main hormones contributing to the emergence of cerebral lateralization.
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PMID:Similarities between sylvian fissure asymmetries in cat brain and planum temporale asymmetries in human brain. 130 16

The developmental and hormonal determinants of the lateralized response to focal cortical suction lesions were examined in a series of experiments. In an initial study, Sprague-Dawley male rats 25, 30, 55 or 90 days of age, received right unilateral focal frontocortical suction lesions. Only 90-day-old rats developed hyperactivity, suggesting a specific role for maturational factors in the production of this response. Prepubertally castrated adult male rats receiving right frontocortical suction lesions at 90 days also failed to develop hyperactivity, suggesting that sexual maturational factors and/or the presence of testosterone are necessary for the expression of this response. Testosterone implants, producing physiological relevant levels of circulating testosterone reinstated the hyperactivity response to adult cortical lesions in prepubertally castrated male rats. Similar lesions in the left hemisphere, however, did not produce hyperactivity in castrated male rats with testosterone replacement. Finally, in ovariectomized adult female rats, testosterone did not allow the expression of a hyperactivity response to right frontocortical suction lesions. Together, these results demonstrate both an organizational and permissive role for sex steroids in the sexually dimorphic asymmetrical response to cortical injury.
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PMID:Developmental and hormonal factors in the sexually dimorphic, asymmetrical response to focal cortical lesions. 292 12

Several standard descriptions of the avian male and female reproductive tract have been reported, including effects of age, stage of reproductive maturity and gonadal hormone concentrations. Limited information on penguin reproductive biology and a lack of information on the African penguin (Spheniscus demersus) necessitated a detailed description of salient structural features of this species and provided an opportunity to evaluate seasonal changes in gonadal steroid hormone concentrations. Tissues from 36 males (adults and juveniles) and 29 females (adults and juveniles) were used for macro-anatomical descriptions and histology of the testes and ovaries. In addition, concentrations of gonadal steroid hormones for eight captive African penguins (four females and four males) were quantified during two breeding and one non-breeding season. The testes were asymmetrical, with the right testis having smaller dimensions compared to the left testis. Marked spermatogenic cellular associations and spermatid developmental stages were present in adult testes only during the breeding season. There was variation in the dimensions of the single ovary during follicular development related to the age and breeding status of the females. Testosterone, dihydrotestosterone, and estradiol concentrations fluctuated during the breeding and non-breeding periods, with males and females having similar steroid concentrations. The results from this study confirm that the breeding status in African penguins can be deduced based on testicular and ovarian histological structures. The results from the present study focused on African penguin reproductive biology should be considered in management strategies for the conservation of the species.
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PMID:Seasonal changes in reproductive anatomy and gonadal hormone concentrations of African penguins (Spheniscus demersus). 3327 91