ABSTRACT In the rat with methylazoxymethanol (MAM)-induced microcephaly, the distribution of corticogeniculate neurons and the projection of genicurocorti- cal fibers were examined using the horseradish peroxidase (HRF’) tracing technique. In agreement with the previous studies, HRP-labeled corticogeniculate neurons in the MAM-rats were irregularly distributed and reduced in number in the occipital cortex and neurons in the LGNd also showed developmental deficits such as reduced cell number and abnormal distribution. It was first demonstrated that in the MAM-rats, the density of HRP-labeled geniculocortical fibers observed in the corpus calosum was remarkably low than the control. Moreover, HRP- labeled fiber plexus in the MAM-rats revealed a layer-like appearance similar to the control. However, its major location did not coincide with layer IV because of the obscure lamination pattern in the superficial and intermediate layers. Besides, in the MAM-rats, the density of the HRP-labeled geniculocortical afferents in the plexus was abnormally high and these afferent terminals showed uneven distribution compared with more uniform distribution in the control. From these observations, it is suggested that there is a possibility of abnormal neuronal contacts be- tween the geniculocortical afferent and the target cortical neurons in the visual cortex.
ABSTRACT The anatomical features of congenital duplication in the bovine calf encountered in 39 cases over eleven years in Hokkaido were investigated macro- scopically. Among the animals studied, 14 were male, 20 female and 5 of unknown gender, and the anomaly was noted in 35 Holstein-Friesians, 3 Japanese Blacks and 1 Hereford. 7 The duplications observed in this study were classified by four types: free asymmetrical, 4 (all 4 acardius); attached symmetrical, 25 (14 cranial duplication, 2 dipygus, 2 dicephalus dipygus, 5 thoracopagus, and 2 pygopagus); attached asymmetrical, 6 (1 parasitic dipygus, 4 notomelia, and 1 pygomelia); and miscellaneous, 4. The four acardii were holoacardii amorphi covered with skin and hair. Cranial duplication was subdivided into five types based on the number of eyes and ears. In symmetrical twins the anterior part of the body was affected in 16 out of 25 cases (64%), the posterior part in 2 out of 25 (8%) and both the anterior and posterior in 7 out of 25 (28%). All were mirror-image duplicates on the various planes, and in some the internal organs had a center of symmetry. All four notomeli calves were female. Among the miscellaneous duplications, three were of the genital organs (male 1, and female 2) and one was a spinal cord duplication.
ABSTRACT Alizarin red-S stained skeletons of the fetuses of the streptozotocin induced (on days 2, 6 and 8 of gestation) diabetic and insulin and buffer treated control rats were examined on day 20 of gestation for malformations and hypoplasia. Hypoplasia of both the neurocranial and viscerocranial bones was significant in all 3 diabetic groups. Insulin treatment had a remarkable rescue effect on fetuses of the day 8 group; a moderately similar response was found in others. Inhibition of ossification of the scapula, humerus, radius and ulna was relatively less remarkable when compared to that of the homologous bones of the hind- limbs. However the metacarpals were affected more than the metatarsals. Day 6 of gestation was particularly susceptible for retardation of sternal ossification. Agenesis, hemi- and double hemivertebrae were also observed in a few cases. Re- duction in caudal sacral and coccygeal vertebral development was remarkable. Incidence of the 14th rib was highest in the day 6 group and insulin administration significantly reduced this abnormality. Meticulous metabolic control had beneficial effect over the growth retarding effects of maternal diabetes but did not completely prevent the malformations.
ABSTRACT Effects of copper and hydrocortisone on the proliferation of cultured fibroblasts from macular mouse, a model of Menkes kinky hair disease, were analyzed by flow cytometry. In fibroblasts from the macular mouse, copper induced cytotoxicity and S-phase accumulation of cell cycle were observed at lower concentrations of copper than in fibroblasts from the controls. However, the fibroblasts cultured with a combination of copper and hydrocortisone revealed recruitment of cell cycle. These results suggest that the proliferative activity of the cells from a macular mouse are more vulnerable to an excess amount of copper than normal, and that supplementation of hydrocortisone is effective for the Menkes kinky hair disease.