ABSTRACT A comprehensive review regarding congenital toxoplasmosis, which is caused by transmission of Toxoplasma gondii from an infected mother to her fetus during pregnancy, is presented. In most cases in humans the route of infection is oral and by either of the two forms of Toxoplasma; cysts in the raw flesh of an infected animal and oocysts in the feces of an infected cat. The clinical manifestations in 9 cases of congenital toxoplasmosis encountered by the author are preserted. The findings of computed tomography (CT) and magnetic resonance imaging (MRI) in 3 of these cases are presented. Delayed migration and myelination are suggested to have occurred in 2 cases in which abnormal MRI findings were noted. These MRI findings reflected the clinical manifestations and may also have reflected the pathologic findings. Experimental studies of transplacental infection following oral inoculation of Toxoplasma oocyst were performed in 3 groups of mice, in which infection of the dams was acute, subchronic, or chronic. The incidence of congenital infection was markedly higher in the acute infection group than in the subchronic or chronic infection groups. The incidence of 19s-Toxoplasma (T)-IgM positivity was also higher in the acute infection group than in either of the other two groups. Women should avoid contact with materials that have potentially been contaminated with cat feces, because Toxoplasma in the form of oocyst evacuated in cat feces is very highly infectious. Congenital toxoplasmosis is often accompanied by severe sequelae involving the central nervous system, but treatment is not effective once the symptoms are manifested. Early diagnosis and early treatment, before symptoms are manifest, are therefore important for the prevention of congenital toxoplasmosis.
Abstract The purpose of this study is to investigate the growth and the developmental dimension and the feature of cranial base transition in unilateral cleft lip and palate (UCLP). With regared to this proposition, we have already submitted a paper in which we compared our study with skeletal reversed occlusion on a scholary journal. The authors will present this proposition in comparison with skeletal class I. The subject group consisted of 15 males and 12 females with UCLP. The control group consisted of 11 males and 14 females with skeletal class I. Standared lateral cephalometric radiographs taken at first medical examination and three years later were used. The three linear dimensions (S-N, S-Ba, N-Ba) and craniobasal angle (N-S-Ba) were measured.
The results were as follows: 1) Females showed no significant difference in S-N, S-Ba and N-Ba but males had smaller S-Ba and N-Ba in the UCLP as compared with the control at the first examination and 3 years later. 2) There were no significant difference in the three distance items, S-N, S-Ba, N-Ba, for females but significantly larger changes in N-Ba appeared in the UCLP as compared with the controls for males. 3) The cranial base angle (N-S-Ba) showed no significant difference between the UCLP and controls for both male and female subjects at any observation time.From the above evidences, it is estimated that the cranial base size and angle in the UCLP as compared with those of controls show no consistent trend owing to possible involvement of differential growth pattern between the anterior cranial base and posterior cranial base. The growth of cranial base itself per se seems to be influenced mutually at minimal level by the maxillofacial growth. This suggests growth patterns of cranial base and maxillofacial region are independent from each other.
ABSTRACT We investigated the application of flow cytometric analysis to evaluate the rat sperm viability and number in the male reproductive toxicity studies. Flow cytometric procedure has been developed to evaluate sperm number and viability that uses fluorescent dye (propidium iodide, PI) to distinguish between viable (negative staining) and dead (positive staining) sperm. Sperm samples were collected from the caudal epididymides of SD rats (13-21 weeks old). PI staining pattems/viabilities were compared among several ranges of sperm concentrations, and several kinds of sperm viability. Viabilities deter- mined by flow cytometry (FC) were also compared with motility by direct microscopical observation in several kinds of sperm viability. No notable changes in the PI staining patterns/viabilities were observed in the range from 1 x lo5 to 6 x lo6 spedml. Essentially similar results were obtained from both FC and microscopical analyses for three degrees of viability sperm: live sperm (general preparation as a control), weakly viable sperm (mixed by vortex mixer for 30 seconds), and dead sperm (treated with 90°C or Triton X-100). Viabilities of normal rat samples were 95.0 iz 4.0% in FC and 93.7 k 4.6% in microscopical observation, indicating good correlation in both analyses. Sperm numbers with FC analysis were approximately 0.8 x lo6 to 1.8 x lo6 sperm per mg indicating good correlation with those by microscopy. It was concluded that the present flow cytometric procedure was objective, rapid and reliable, and that it was one of the useful methods for measuring the number and evaluating the viability of sperm collected from the caudal epididymides of rats in the male reproductive toxicity studies.
ABSTRACT We examined the time and order of appearance of ossification centers of various bones in hand and foot in newborn Jcl:ICR mice by staining on days 22, 24, 26 and 28 post coitum (pc) by the alcian blue and alizarin red S staining procedure. The time of appearance of ossification centers of the carpal bones was from about day 22 pc to about day 26 pc, while the ossification centers of the tarsal bones appeared from preterm to about day 28 pc. The order of appearance of ossification centers of respective bones in mice was roughly similar to humans and rats. In carpal bones, ulnar sesamoid, centrale. fused 4th and 5th distal carpal and ulnare appeared first. Then, fused radiale and intermedium and 3rd distal carpal appeared. Finally, 1st distal carpal, 2nd distal carpal, and the last pisiform appeared. In the tarsal bones, fibulare and intermedium appeared first. Then, 1st distal tarsal, fused 4th and 5th distal tarsal and 3rd distal tarsal appeared. Finally, 2nd distal tarsal, centrale and tibiale appeared. In other mammals (humans, chimpanzees, rhesus monkeys and rats), it has been shown that the carpal and tarsal bone ossification of females starts earlier than that of males. However, in this study in mice, there was no such sex difference. The timing of ossification of carpal and tarsal bones in mice is of practical importance in determining the developmental status of hand and foot of mice in the field of neonatal teratology.
ABSTRACT The effect of maternal hyperphenylalaninemia on postnatal brain development was examined. Maternal hyperphenylalaninemia was induced by giving chow supplemented with 6% phenylalanine (Phe.) and 0.12% p-chlorophenylalanine (PCPA) for at least one month before coupling and then throughout pregnancy. Offspring from hyperphe- nylalaninemic mothers were given a normal diet from the first day after birth. Infant mice were killed on the 21st, 28th and 56th day after birth. The protein, RNA and DNA in the brain were measured to determine the biochemical changes. Maturation of the dendrite of pyramidal cells was also examined by the Golgi method. The body weight of the offspring born to mothers, which had been treated with Phe. and PCPA during pregnancy, was significantly less than that of the control. The gain of cerebral weight showed a similar pattern with that to the body weight. The total protein, RNA and DNA contents in the cerebrum of the treated group were also reduced significantly on 21st, 28th and 56th days after birth. The dendritic arborization of the cortical pyramidal neurons in the layer V showed significant reductions in the offspring born to hyperphenylalaninemic mothers compared with the age-matched control at 21, 28 and 56 days after birth. These findings suggest that maternal hyperphenylalaninemia during pregnancy causes an irreversible retardation of the neuronal maturation both biochemically and morphologically, and subsequently gives rise to disorders of the higher cortical functions.
SUMMARY Migration of cardiac mesenchymal cells of chick embryos was examined in vitro. The conotruncal cushion and atrioventricular cushion cells of 6-day-old chick embryos were cultured on collagen gel in Dulbecco's modified Eagle's medium with chicken serum or calf serum, or no serum. After 48 hr of incubation, the culture was fixed with 4% formaldehyde, and photographed. The migration area of mesenchymal cells spread from the transplanted tissue was measured by digitizing the photographs. Then, the migration distance of mesenchymal cells was computed from the area with a personal computer. Mesenchymal cells cultured with chicken serum migrated a significantly longer distance than those with calf serum or no serum. Under the designed conditions, the migration distance of the mesenchymal cells of the conotruncal cushion was longer than that of the atrioventricular cushion. These results show that certain factor(s) in serum stimulates migration activity of cardiac mesenchymal cells, but the mammalian factor(s) is not cross-reactive to cardiac mesenchymal cells of birds. Different effects of the serum from different species on the migration activity of chick cardiac mesenchymal cells were shown in the present results. At the same time, it was revealed that migration activity of mesenchymal cells of the conotruncal cushion is different from that of the atrioventricular cushion.
SUMMARY Bis-diamine is a teratogen which induces conotruncal anomalies in rats and chicks. Bis-diamine induces endocardial cushion defects in rats but it does not induce in chicks. In the present study, we examined effects of bis-diamine to chick embryonic cardiac mesenchymal cells. Chick embryos of 3 days incubation (E3, H.H. stage 17-28) were treated with 100 yg of bis-diamine dissolved in 50 y1 dimethylsulfoxide. The conotruncal and atrioventricular cushions of the E6 embryos treated with bis-diamine were cultured with chicken serum. After 48 h of incubation, the culture was fixed with 4% formalde- hyde. The area of grown out mesenchymal cells from the transplanted tissue was measured, and then the migration distance of mesenchymal cells was computed from the area. In the group treated with bis-diamine, the migration distance of conotruncal cushion mesenchymal cells was significantly shorter than that of controls. However, the migration distance. of atrioventricular cushion mesenchymal cells was not diminished. By scanning electron microscopy, the superior endocardial cushion of E4.5 or E5 embryos treated with bis-diamine was slightly hypoplastic compared with the inferior endocardial cushion. In spite of hypoplasia of the superior and inferior endocardial cushions, these cushions fused in E6 embryos treated with bis-diamine. These results have shown that bis-diamine affects migration activity of conotruncal cushion mesenchymal cells but it does not severely affect that of the atrioventricular cush- ion in chicks. This portionally different effect of bis-diamine can explain that bis-diamine does not frequently induce endocardial cushion defects in chicks.
ABSTRACT Selective breeding of rat strains showing high and low avoidance behavior in the shuttlebox test has been performed since 1985. To elucidate the postnatal behavior of the high and low avoidance strains, animals from both lines were subjected to an open-field test, wheel cage activity test and Biel maze test in the 13th, 14th and 16th generations, respectively. No significant differences in any parameter in the open-field test were observed be- tween high and low avoidance lines. However, animals from the high avoidance line showed higher motor activity in the wheel cage and fewer errors in the Biel maze than the low avoidance line.
ABSTRACT We examined mutations in the gene encoding the fibroblast growth factor receptor 3 (FGFR3) in nine Japanese patients diagnosed as typical achondroplasia (ACH) and two patients with hypochondroplasia (HCH) using polymerase chain reaction (PCR) coupled with direct sequencing. In our present cases, equivalent to previously reported cases in France and the U.S.A., all mutations affected with ACH were the same nucleotide change, a G+A transition at position 1,138, resulting in the substitution of arginine for glycine at position 380 of the mature protein. Therefore, the gene mutation of ACH indicates no significant differences between the Caucasian and the Japanese. On the other hand, PCR products from genomic DNA of HCH did not show the same mutation.