Central nervous system malformations induced by triamcinolone acetonide in nonhuman primates: pathology

Triamcinolone acetonide (TAC) was administered to pregnant macaques (Macaca mulatta [15] and M. radiata [7]) during gestational days (GD) 23 to 41 using various dosing schedules. A daily dose of 10 mg/kg is approximately equal to 100 x the human dose equivalent. The brains of the fetuses and infants were studied grossly and histologically. All cases displayed either the mild form of the TAC-induced syndrome (craniofacial dysmorphia, cranium bifidum occultum, meningocele, and mild distortion of the midbrain) or the more severe form (occipital encephalocele, hydrocephalus, severe distortion of the midbrain or midbrain "beaking," shunting of cerebrospinal fluid, and craniofacial malformations). The dysmorphology was dose-related, with severity increasing at higher doses or with increased numbers of treatments. Individual cases were assessed for the severity of the syndrome by comparison of like components between groups. The lesions observed were morphologically comparable to those described in spontaneous human cases; the TAC-induced occipital encephaloceles were associated with brainstem and cerebellar abnormalities, and, with the less severe form of the syndrome, brainstem abnormalities were occasionally present, with occipital meningoceles. Controversy exists concerning the significance and temporal development of the midbrain changes. However, the associated alteration in aqueduct conformation may have been responsible for functional compromise and ensuing hydrocephalus.     

Morphogenesis of the respiratory bronchiole in rhesus monkey lungs

The epithelium of the respiratory bronchiole in the adult rhesus monkey consists of two populations: a pseudostratified epithelium with basal, mucous goblet, and ciliated cells located near the pulmonary artery (PA); and a simple cuboidal epithelium composed only of nonciliated bronchiolar epithelial (or Clara) cells in areas away from the PA. This study describes the pattern of differentiation of these two epithelial populations, and their relationship to the PA and to the time of appearance of alveoli in the respiratory bronchiole of the rhesus monkey during the period of 90-125 days gestational age (DGA). These events were related to changes in the adjacent parenchyma. Dissected airways of infusion-fixed, critical-point-dried lungs were evaluated by scanning microscopy followed by light microscopy of the same airways. At 54% of gestation (90 DGA), the distal airway was lined by a mixture of ciliated and nonciliated cells. By 67% of gestation (110 DGA), the ciliated cells were confined to the epithelium over the PA. The underlying connective tissue initially was cellular containing few fibers but was fibrous by 76% of gestation (125 DGA). Alveolarization began near the most distal cartilage at 57% of gestation (95 DGA), the same period at which secondary septation occurred in the distal acinus. Thus, alveolarization occurred simultaneously in two centers: 1) the proximal centriacinar region in the vicinity of the most distal cartilage and 2) the distal lung parenchyma. The duration of centriacinar alveolarization was short, approximately 5 days.     

Diethylstilbestrol-induced cervical and vaginal adenosis using the neonatal mouse model

The relevance of diethylstilbestrol (DES) administration to neonatal mice as a model for human pathology attributed to the use of DES in high-risk pregnancies has been investigated, particularly with respect to cervical and vaginal changes in female offspring. Neonatal DES treatment of mice results in tonic pituitary gonadotropin release and continuous estrogen secretion by the ovary. Studies were designed to determine the effect of this altered ovarian endocrine activity on cervical and vaginal histopathology. Ovariectomy of DES-treated mice, with or without estradiol replacement, did not eliminate the lesions, nor did estrogen and progesterone administered in a regimen intended to mimic estrous cycle changes. Induction of the constant estrus state by neonatal estradiol benzoate or testosterone propionate administration or by exposure to constant light did not produce the type of vaginal or cervical changes seen in DES mice. Thus, altered ovarian function is apparently not required for the vaginal and cervical changes appearing in later life. A role for endogenous (or exogenous) ovarian hormones in the developmental progression toward normality is suggested.     

Effect of orientational order on the decay of the fluorescence anisotropy in membrane suspensions. Experimental verification on unilamellar vesicles and lipid/alpha-lactalbumin complexes

Various models for the analysis of time-dependent fluorescence anisotropy measurements were evaluated. The discussion was based on the analysis of pulsed experiments with 1,6-diphenyl-1,3,5-hexatriene embedded in small unilamellar vesicles of dimyristoylphosphatidylcholine or dipalmitoylphosphatidylcholine and in dimyristoylphosphatidylcholine/alpha-lactalbumin complexes. It was shown that a recently proposed model (Van der Meer, W., H. Pottel, W. Herreman, M. Ameloot, H. Hendrickx, H. Schröder, 1984, Biophys. J., 46:515-523) described the data better than did the earlier suggested cone model (Kinosita K., Jr., S. Kawato, and A. Ikegami, 1977, Biophys. J., 20:289-305). This permitted the use of the new model for the estimation of the second- and fourth-rank order parameters on nonoriented systems. The results indicated that a fraction of the probes was oriented perpendicularly to the preferred direction of the lipids. An increase of the rotational correlation times of the fluorescent probe and a higher order of its environment were detected after the interaction of alpha-lactalbumin with the dimyristoylphosphatidylcholine vesicles at acidic pH at 24.2 degrees C.     

Influence of osmotic stress on the respiration of potato tuber callus

Potato tuber ( Solanum tuberosum L. cv. Bintje) callus shows a decrease in fresh weight and an increase in dry weight upon transfer to nutrient medium supplemented with 0.3 or 0.5 M mannitol. The osmolarity of the intracellular fluid increases simultaneously. Probably mannitol is taken up from the medium till the osmolarity of the tissue is in equilibrium with that of the medium. After osmotic adaptation, on a medium with 0.5 M mannitol, growth is negligible, although the tissue retains its viability.
Respiration increases upon transfer to medium with extra mannitol, especially when expressed on a fresh weight basis. On this basis cytochrome and alternative pathway capacities do not change appreciably. The respiratory increase is exclusively caused by an increased engagement of the alternative pathway. The participation of this pathway in uninhibited respiration increases from about 10 to 90% upon transfer to medium with extra mannitol. The increase in respiration is partly correlated with the decrease in fresh weight upon transfer. Per disc, the capacities of the cytochrome and alternative pathway decline. Yet, total respiration per disc significantly increases due to the increased participation of the alternative pathway. This results in an almost equal ATP-production per disc before and after transfer. We suggest, that the alternative pathway functions as a reserve capacity in potato callus, which is switched on when ATP-production coupled to the cytochrome pathway is impaired.     

Monitoring ovulation and implantation in the cynomolgus macaque (Macaca fascicularis) through evaluations of urinary estrone conjugates and progesterone metabolites: a technique for the routine evaluation of reproductive parameters

Investigations were undertaken to determine the applicability of recently reported specific radioimmunoassays for urinary estrone conjugates and progesterone metabolites for monitoring ovarian function in the cynomolgus macaque (Macaca fasciularis) and other macaque species. Mean estrone conjugate measurements appear to accurately reflect the preovulatory estrogen peak in both conceptive (n = 5) and nonconceptive (n = 6) cycles, as well as to indicate early pregnancy through increases which are significantly elevated by Day + 15 (p less than 0.049) post estrone conjugates peak. The mean luteal phase levels of these progesterone metabolites are significantly elevated by Day + 14 (p less than 0.012) in conceptive cycles when compared to the mean values for nonconceptive cycles.     

Craniofacial and central nervous system malformations induced by triamcinolone acetonide in nonhuman primates: II. Craniofacial pathogenesis

This study further defines the craniofacial malformations induced by triamcinolone acetonide in the rhesus monkey. Ten timed-mated pregnant rhesus monkeys (Macaca mulatta) received intramuscular injections of 10 mg/kg TAC on days 23, 25, 27, 29, and 31 of gestation. Results of previous experiments with rhesus and bonnet monkeys and baboons indicated that specific craniofacial and brain malformations could be induced with TAC during this period of pregnancy (Hendrickx et al., '80). Stage-matched TAC-treated and control embryos (stages 17-18 and 22) and age-matched TAC-treated and control fetuses (50, 60, and 70 days gestation) were removed by hysterotomy. Stage 17-18 TAC embryos appeared grossly normal but histologic evaluation revealed a shortened anlage of the posterior cranial base. Stage 22 TAC embryos and all TAC fetuses exhibited craniofacial dysmorphia and encephalocele. The developing sphenoid was the earliest affected and most severely malformed bone. Its defects included reduced anterioposterior and transverse dimensions, reduced orbitosphenoid and alisphenoid, abnormal pituitary fossa, and reduced dorsum and tuberculum sellae. In addition, shortening of the posterior cranial base and decreased cranial base angle was a consistent finding in the treated embryos and fetuses. Decreased ossification and remodeling in the facial bones and abnormal position due to the malformed sphenoid occurred.     

Movement of cynomolgus and rhesus monkey spermatozoa collected from the lower female reproductive tract

Postcoital (pc) cervical mucus was collected in 73 menstrual cycles of cynomolgus monkeys and in 43 cycles of rhesus monkeys at 2,6,10,30 hr pc. Videomicrography was used to analyze sperm numbers and movement in the mucus. Both cynomolgus and rhesus monkeys had comparable populations of motile sperm in the mucus at 2 hr pc. However, by 6 hr pc, cervical mucus from cynomolgus monkeys contained twice as many total sperm and motile sperm as mucus from rhesus monkeys (P <.05). Mean swimming speeds of the free-swimming cervical sperm were similar for the two species at this time. No motile sperm were recovered in mucus from rhesus monkeys at 30 hr pc. In cynomolgus monkeys, however, 14 of the 26 animals examined at 30 hr pc had motile sperm in their mucus. These sperm exhibited lower percent molility, percent free-swimming sperm, and swimming speed than those sperm observed at 6 hr pc. Uterine sperm were collected by transcervical or transuterine aspiration from cynomolgus monkeys. In the transcervical technique, sperm were successfully obtained in four of nine animals examined at 6 hr and in four of five animals at 30 hr pc. The percentage of motile sperm in the uterine fluid was high, 82% ± 4%, and the swimming speeds (86 ± 2μm/sec) were higher than those observed in cervical mucus. Approximately 5–10% of the uterine sperm exhibited swimming motions similar to the hyperactivated motility seen in most mammals. These findings indicate that the sperm cervical mucus interaction in vivo in cynomolgus monkeys has more similarities to the human situation than does the interaction in rhesus monkeys.