The effect of thymosin fraction 5 and its synthetic component thymosin-alpha 1 on rat open-field behavior

The effect of thymosin fraction 5 and its synthetic component thymosin-alpha 1 administered i. p. and i. c. v. on the behavior of 219 Wistar rats in the open field was studied to establish the effective dose and time of action of both substances. It was shown that at i. c. v. administration of both compounds in a dose of 10 ng the motor activity was suppressed for about 0.5 hour. At i. p. administration thymosin fraction 5 in doses of 0.15, 0.3 and 0.6 mg/kg suppressed the motor activity for more than 2 hours. The higher the dose, the greater the degree of suppression of the motor activity. Both peptides influence in a similar way the motor activity of the animals irrespective of the route of administration.     

Shape changes produced in detergent extracted bovine retinal pigment epithelium when exposed to ATP. A comparison with fibroblasts and smooth muscle cells

The response of single detergent treated bovine retinal pigment epithelial cells in culture to ATP was measured with an image analyser. The most pronounced contraction was produced by 1.0 mM ATP with most change taking place in the first 10 min. At 1 h the area had decreased by about 33%, perimeter 22% and maximum length 25%. By way of comparison rabbit skin fibroblasts had a decreased area of approximately 40%, perimeter 25% and maximum length 22%. Bovine aortic smooth muscle cells on the other hand decreased in area by 55%, perimeter 40% and maximum length 36%. It is hoped that this assay may be used to evaluate drugs which could counteract contractile events in proliferative vitreoretinopathy.     

Rapid change in height and body proportions of Maya American children

Maya families from Guatemala migrated to the United States in record numbers from the late 1970s to the early 1990s. Births to Maya immigrant women have created a sizable number of Maya American children. The height and sitting height of 5 to 12 years children (n = 431) were measured in 1999 and 2000. Leg length was estimated and the sitting height ratio was calculated. These data were compared with a sample of Maya children living in Guatemala measured in 1998 (n = 1,347). Maya American children are currently 11.54 cm taller and 6.83 cm longer‐legged, on average, than Maya children living in Guatemala. Consequently, the Maya Americans have a significantly lower average sitting height ratio (i.e., relatively longer legs in proportion to length of the head and trunk) than do the Maya in Guatemala. These results add support to the hypothesis that both the height and body proportions of human populations are sensitive indicators of the quality of the environment for growth. Am. J. Hum. Biol. 14:753–761, 2002. © 2002 Wiley‐Liss, Inc.     

Sphincter injury after anal dilatation demonstrated by anal endosonography.

Anal dilatation is still used in the treatment of anal fissure and haemorrhoids. Using anorectal physiology and anal endosonography we have studied 12 men presenting with faecal incontinence following anal dilatation. Resting anal pressures were low, pudendal nerve latencies were normal; 11 men had a disrupted internal anal sphincter and in ten this was extensively fragmented. Three also had defects of the external anal sphincter. These findings demonstrate for the first time the nature of the structural injury which may be caused by anal dilatation.