bluuebunny/crossref_metadata_2025_split huggingface dataset:
The facial features of holoprosencephaly in anencephalic human specimens. II. Craniofacial anatomy
Authors: Siebert Joseph R. , Kokich Vincent G. , Beckwith J. Bruce , Cohen M. Michael , Lemire Ronald J. 
Published: June 2005

AbstractThe craniofacial anatomy of two anencephalic human specimens with the facial features of holoprosencephaly is reported. Many of the malformations have distinctly holoprosencephalic or anencephalic features. Absence of the entire ethmoid complex, observed in both specimens of the present study, has rarely been described and, to our knowledge, has never been confirmed histologically. The significance of agenesis of the ethmoid bone in the development of normal and holoprosencephalic facial features has not been considered previously. On the basis of several morphological variations in the two specimens described, it is evident that the ethmoid bone provides integral support in multiple planes for tissues of the median face. It is postulated that the spatial relationships of the bony and soft tissue components of the median face are guided and maintained by the ethmoid complex during morphogenesis. Specifically, hypotelorism and superiorly displaced structures of the nose and upper lip may well represent migration of embryonic tissues into areas normally occupied by the ethmoid bone. Absence of the sella turcica and pituitary gland is ascribed to the holoprosencephalic process. A variant of choanal atresia, due to collapse of the pterygoid plates, is described.
Morphogenesis of axial skeletal (dysraphic) disorders induced by aliphatic nitriles
Authors: Willhite Calvin C. , Marin‐padilla Miguel , Ferm Vergil H. , Smith Roger P. 
Published: June 2005

AbstractThe previous study (Willhite et al., '81) linked the administration of acrylonitrile or propionitrile in the pregnant hamster to the production of severe axial skeletal (dysraphic) malformations in the hamster fetus. The present investigation dealt with histological study of both early embryos and term fetuses challenged with a teratogenic dose of either of these nitriles. Inspection of hamster embryos 10 hours after the teratogenic stimulus revealed mesodermal changes including a reduced number of cells, shrinkage of the cell cytoplasm, and enlarged extracellular spaces. In addition, a reduced number of mitotic figures and focal necrobiosis were noted. The affected embryos were smaller and were delayed in their development as compared to controls. Analysis of the fourteen‐day‐old hamster fetuses revealed the basichondrocranium in both cranioschisis occulta with encephalocoele and cranioschisis aperta with exencephyaly to be shorter than control and lordotic to the vertebral axis. These alterations were more accentuated in cranioschisis aperta than in cranioschisis occulta. The ultimate skeletal malformations may be the reflection of a primary paraxial mesodermal insufficiency.
Teratogenic effects of proline analogue L‐azetidine‐2‐carboxylic acid in hamster fetuses
Authors: Joneja M. G. 
Published: June 2005

AbstractThe teratogenic effects of L‐azetidine‐2‐carboxylic acid (LACA) were evaluated in hamsters. Single or multiple intraperitoneal injections of LACA were given on gestational days 7–12. Fetal weights were significantly reduced in several LACA‐treated groups as compared to controls. The frequency of external anomalies was significantly higher than controls in only two LACA‐treated groups: 7.2% in 600 mg/kg on day 12 and 9.6% in 200 mg/kg/day on days 10–12. Subcutaneous hemorrhage and cleft palate were the most frequently occurring externally visible defects. Skeletal anomalies such as retarded ossification, asynchronous vertebral ossification and shortening of bones were found in a high percentage of LACA‐treated fetuses. The major teratological effect of LACA appeared to be the retardation of skeletal development.
Effects of pretreatment with SKF‐525A, N‐methyl‐2‐thioimidazole, sodium phenobarbital, or methyl cholanthrene on ethylenethiourea‐induced teratogenicity in rats
Authors: Khera K. S. , Iverson F. 
Published: June 2005

AbstractSKF‐525A (SKF), a well known inhibitor of P450 function, and N‐methyl‐2‐thioimidazole (MMI), an antithyroid drug resembling ethylenethiourea, were tested at the respective dosages of 40 mg/kg ip and 200 mg/kg po, for their individual or combined effect on the teratogenicity of an oral dose of 60 mg/kg ethylenethiourea (ETU). All chemicals were dissolved in distilled water and administered to rats on the 13th day of pregnancy. MMI and ETU were dosed simultaneously, one hour after dosing with SKF. Control groups were given equivalent doses of ETU (positive control), SKF, MMI, or SKF + MMI. Term fetuses were evaluated for anomalies according to the established procedures. No teratogenic activity was attributed to treatments with SKF, or MMI, or their combination. However, in the remaining test groups, MMI + SKF + ETU, or SKF + ETU, the type, incidence, and intensity of anomalies, compared to the group given only ETU, were markedly increased and were similar to those previously reported to occur at 120 mg/kg or higher doses of ETU. Pretreatment with either 40, 60, or 80 mg/kg of sodium phenobarbital injected once or twice a day on days 9–12 of pregnancy, or 20 mg/kg/day of methylcholanthrene on days 11–13 of pregnancy, failed to alter significantly the teratogenicity of a subsequent dose of 60 mg/kg of ETU given orally on the 13th day of pregnancy.
Congenital malformation surveillance
Authors: Bod Maria , Czeizel Andrew 
Published: June 2005

AbstractRecords (24,798) of the Hungarian Congenital Malformations Registry for the 728,343 total births in 1973–1976 were examined. A total of 3,116 babies were identified as having a primary congential abnormality which may be associated with secondary developmental anomalies. Some 842 of these babies had 1,194 additional congenital abnormalities that we consider to be secondary. The exclusion of these secondary abnormalities from birth prevalence figures represents a more accurate registration and evaluation of congenital abnormalities from both statistical and etiological points of view.
Teratological effects of Western equine encephalitis virus on the fetal nervous system of Macaca mulatta
Authors: London W. T. , Levitt N. H. , Altshuler G. , Curfman B. L. , Kent S. G. , Palmer A. E. , Sever J. L. , Houff S. A. 
Published: June 2005

AbstractFetal rhesus monkeys were inoculated intracerebrally with an attenuated strain of western equine encephalitis virus. All animals developed micrencephaly. Twelve of sixteen monkeys developed ex vacuo hydrocephalus. All virus inoculated fetuses developed WEE virus antibody. Virus could hot be recovered at the time of delivery. Monkeys with the highest WEE antibody titers showed the greatest degree of hydrocephalus.
Regulatory aspects of teratology: Role of the food and drug administration
Authors: Kelsey Frances O. 
Published: June 2005

AbstractThe Food and Drug Administration is a scientific regulatory agency whose consumer protection activities cover a wide range of products including foods and additives, and pesticide residues on foods; drugs; cosmetics; medical devices; and radiation‐emitting electronic products. Amongst its concerns is the possible teratogen effects of regulated products to which the pregnant woman is exposed. The policies and programs of the agency directed toward reducing such risks to the unborn are reviewed. These measures include guidelines for animal reproduction studies and for clinical trials involving women of childbearing potential; labeling of products to disclose known or possible harm to the fetus or embryo; surveillance procedures designed to detect previously unsuspected adverse effects of marketed products; research activities designed to develop better understanding of developmental toxicology and improved techniques for detecting embryocidal and embryotoxic effects; and educational efforts directed both to professionals and the public regarding hazards to the unborn of agency‐regulated products.
The asplenia syndrome: An explanation for absence of the spleen
Authors: Monie Ian W. 
Published: June 2005

AbstractStudy of a case of the so‐called asplenia syndrome with a miniscule spleen suggested that the latter was caused by the pressure of neighboring viscera and interference with blood supply. Consequently, it is considered that splenic disturbance arises independently of the other malformations in this syndrome. It is also possible that similar factors may be operative in the formation of multiple spleens in the polysplenia syndrome.
Fetal manifestation of a chromosomal disorder: Partial duplication of the long arm of chromosome 5 (5q33→qter)
Authors: Passarge Eberhard , Bartsch‐Sandhoff Margret , Rehder Helga 
Published: June 2005

AbstractTwo live‐born children and one fetus were found to be affected by autosomal imbalance consisting of a partial duplication of the long arm of chromosome 5 (5q33→qter) and partial deficiency of the short arm of chromosome 8 (8p23‐pter), resulting from segregation of a paternal translocation heterozygote t(5;8) (q33;p23). The phenotype of the children was rather similar to that of the fetus. The main features included Craniofacial dysmorphia consisting of downward slant of eyelids and corners of the mouth, flat and widened nasal bridge, prominent philtrum, and small mandible. Ventricle and atrium septum defects were associated with overriding aorta and right heart hypertrophy in all three. Statomotoric retardation was evident postnatally in the two children. This observation indicates that structural autosomal imbalance may produce a fetal phenotype that is specific for the karyotype and comparable to that seen in the newborn.
Infections in pregnancy: Highlights from the collaborative perinatal project
Authors: Sever John L. 
Published: June 2005

AbstractThe longitudinal study of approximately 60,000 pregnant women was conducted at 14 major medical centers throughout the United States. Clinical data was obtained under prescribed protocols for each of the study women throughout their pregnancy, at delivery, and through the postpartum period. The children were followed with uniform examinations from birth through seven years of age. In addition blood samples were taken from the pregnant women at registration, every two months through pregnancy, at delivery, and six weeks postpartum. Cord blood samples were also taken from the children during the last half of the study. We have used this material from the Collaborative Perinatal Project for the investigation of the role of infections in the production of damage to the fetus and newborn.The frequency of clinically recognizing infections during pregnancy was determined and geographic variation was demonstrated. Serological tests were used to document certain diseases. The frequency of confirmed clinical cases per 10,000 were: rubella, 8; rubeola, 0.6; mumps, 10; varicella‐zoster, 5. The epidemiology and clinical findings associated with infections were studied using serological methods. This has provided data on the frequencies of infections such as cytomegalovirus, herpes simplex, mumps, rubeola, respiratory syncytial virus, and others. The study of abnormal pregnancies and matched controls is in progress using serological techniques. A number of specific studies have been reported on infections including rubella, neonatal meningitis, cytomegalovirus, maternal urinary tract infections, and toxoplasmosis. Further testing is now in progress employing more sophisticated laboratory methods and more complete data analysis.
Susceptibility to cleft palate and the major histocompatibility complex (H‐2) in the mouse
Authors: Vekemans M. , Fraser F. C. 
Published: June 2005

AbstractThe congenic mouse strains B10 and B10.A differ genetically only at the H‐2 locus, B10 having the H‐2b and B10.A the H‐2a haplotype. The two strains also differ in susceptibility to cortisone‐induced cleft palate, B10 being more resistant than B10.A Since stage of palate closure is also associated with susceptibility to cortisone‐induced cleft palate it was postulated that the H‐2 haplotype may affect the cortisone‐induced cleft palate susceptibility by altering the stage of palate closure. The present study shows that palate closure occurs at the same stage in the two strains, so this hypothesis must be rejected.
Computer program for searching the biomedical literature in teratology, developmental biology, and reproductive biology
Authors: Brent Robert L. 
Published: June 2005

AbstractA word profile program has been developed in conjunction with the services of the Institute for Scientific Information for surveying the literature in teratology, developmental biology, and reproductive biology. It has been revised many times to improve the discriminating qualities of the program. It should provide scientists with a current review of the published articles in the field for a relatively low cost. This same program, if purchased as an individual subscriber, would cost ten times the ISI regular subscription price for the ASCA service. Colleagues and subscribers are encouraged to make recommendations that will improve the program.
An epidemiologic study of neural tube defects in Los Angeles County I. Prevalence at birth based on multiple sources of case ascertainment
Authors: Sever Lowell E. , Sanders Mark , Monsen Rita 
Published: June 2005

AbstractEpidemiologic studies of the neural tube defects (NTDs), anencephalus and spina bifida, have for the most part been based on single sources of case ascertainment in past studies. The present investigation attempts total ascertainment of NTD cases in the newborn population of Los Angeles County residents for the period 1966–1972. Design of the study, sources of data, and estimates of prevalence rates based on single and multiple sources of case ascertainment are here discussed. Anencephalus cases totaled 448, spina bifida 442, and encephalocele 72, giving prevalence rates of 0.52, 0.51, and 0.08 per 1000 total births, respectively, for these neural tube defects–rates considered to be low. The Los Angeles County prevalence rates are compared with those of other recent North American studies and support is provided for earlier suggestions of low rates on the West Coast.
Interactions between cycloheximide and T‐locus alleles during mouse embryogenesis
Authors: Lary Joseph M. , Hood Ronald D. , Lindahl Ronald 
Published: June 2005

AbstractFemale CD‐1 mice were mated with CD‐1 × T/ + F1 males that were heterozygous for the brachyury (T) semidominant lethal gene or were +/+. Fetuses from CD‐1 × +/ + matings were normal when observed on gestation Day 17 (plug day = Day 0). Those from the CD‐1 × T/+ cross exhibited the expected 1:1 ratio of short:normal tail lengths, but 10% of these fetuses were tailless, apparently due to factors in the CD‐1 genotype that increased the expressivity of the T‐gene with regard to reduction of tail length. Additional CD‐1 females were mated with CD‐1 × tw18/+ F1 males. Fetuses from the CD‐1 × tw18/+ matings were normal. CD‐1 females carrying CD‐1 X +/+, CD‐1 × T/+, or CD‐1 × tw18/ + litters were injected ip on gestation Day 9 with 30 mg/kg cycloheximide or were untreated. Cycloheximide was teratogenic for litters from all three crosses. Polydactyly, oligodactyly, and a variety of skeletal abnormalities were observed. Gross malformations and total skeletal malformations were increased in treated CD‐1 × T/ + or tw18/ + litters in comparison with CD‐1 × +‐/ + litters, as were nonvertebral skeletal defects in CD‐1 × tw18/+ litters. Prenatal mortality was also greater in treated mutant‐containing litters than in + / + litters, and fetal weights were similarly decreased in treated CD‐1 × tw18/ + litters. The incidence of taillessness was also higher in treated (26%) than in control (10%) CD‐1 × T / + litters. Thus both the T and tw18 alleles appear to have enhanced the teratogenicity of cycloheximide, and the inhibitor may have increased the expressivity of T.
Characteristics of the androgenization produced in mice by neonatal exposure to alpha‐fetoprotein antibodies
Authors: Mizejewski G. J. , Vonnegut M. 
Published: June 2005

AbstractNeonatal male and female mice, ages 1–5 days, were injected intracranially with either anti‐alpha‐fetoprotein (AFP) IgG, steroids, or various control solutions. The mice were autopsied 60–70 days later and the spleen, thymus, liver and gonads were examined by light microscopy. The antibody to AFP produced a gonadal response which was sexual specific. Histological examination of the tissue sections from female mice treated with either anti‐AFP IgG or steroids revealed the presence of polyfollicular ovaries lacking in corpora lutea formation. A comparable antibody‐induced specific effect on the testes could not be demonstrated; however, steroidal administration induced aspermatogenesis and delayed maturation in parallel studies. In the anti‐AFP IgG‐treated groups, there appeared a gross neurological lesion which was termed external hydrocephaly. The physiologic responses in the female gonad were found independent of the presence of this anatomical brain lesion, whereas those in the male gonad were found causally related. The immunological specificity of the gonadal response was demonstrated by the use of IgG devoid of anti‐AFP IgG and by various IgG control solutions. Thus, exposure to anti‐AFP IgG during the critical period of sexual development in the brain appears to mimic steroidal androgenization of the female mouse.
Trisomy 16 in the mouse fetus associated with generalized edema and cardiovascular and urinary tract anomalies
Authors: Miyabara Shinichi , Gropp Alfred , Winking Heinz 
Published: June 2005

AbstractMurine trisomy (Ts) 16 occurs in the fetal and neonatal progeny of males doubly heterozygous for the Robertsonian metacentric chromosomes Rb(16.17)7Bnr/Rb(9.16)9Rma and “all acrocentric” females. The developmental aspects of this trisomy were studied between day 12 of gestation and birth. So far, postnatal survival longer than a few hours after birth has not been observed. The frequency of Ts 16 among all implants decreased from more than 20% on day 14 to values between 4% and 7% shortly before term.Main features of Ts 16 are moderate general hypoplasia, slight developmental retardation, and cardiovascular anomalies. These latter were found in 96% of the trisomies, the great majority belonging to the transposition type, i.e., riding aorta, double outlet right ventricle (DORV) and transposition of the great arteries (TGA). Association with common atrio ventricular (AV)‐canal was frequent. Other anomalies as “open eyelid”, hydronephrosis, and hydroureter seem to be attributable to the effects of retardation. Generalized transient edema was frequent in the later gestational stages of Ts 16.Severe cardiovascular malformation is possibly one of the factors responsible for late fetal or neonatal death in some cases. Another factor probably contributing to Ts 16 fetal mortality is insufficiency of placental function due to hypoplasia of the fetal vasculature of this organ. The teratological study of Ts 16 demands interest since evidence has been forwarded to consider this trisomy as an animal model of human trisomy 21.
Effects of mercury compounds on ovulation and meiotic and mitotic chromosomes in female golden hamsters
Authors: Watanabe Toshiaki , Shimada Takamichi , Endo Akira 
Published: June 2005

AbstractWhen female golden hamsters were subcutaneously injected with either CH3HgCl or HgCl2 in doses of 6.4 mg or 12.8 mg Hg/kg body weight, the incidence of chromosome aberrations was slightly increased in bone marrow cells, but not in metaphase II oocytes. In the HgCl2‐treated animals the ovulation was inhibited, although mercury concentrations in ovaries were relatively low. However, in the CH3HgCl‐treated groups, despite high concentrations of mercury in ovaries, the ovulation was not affected.
Altered glycosaminoglycan composition of rat forelimb‐buds during hydroxyurea teratogenesis: An indication of repair
Authors: Sugrue Stephen P. , Desesso John M. 
Published: June 2005

AbstractWe report here the effect of hydroxyurea (HU), which is an inhibitor of DNA synsthesis and a known cytotoxic and teratogenic agent, on the composition of glycosaminoglycans (GAGs) in the extracellular matrix of the developing forelimb of the rat. HU injected on day 12 has been shown to produce one missing digit and multiple missing digits on day 13 (Ritter et al., '73). Pregnant Wistar rats were treated (IP) with 1,000 mg/kg HU on either day 12 or day 13 (9:00 a.m.) of gestation and sacrificed 0–96 hours later. Forelimbs were dissected and pooled by litter. GAGs were extracted and then separated by microzone electrophoresis on cellulose acetate membranes. Identification of GAG was confirmed by digestion with specific polysaccharidases. Such analysis of control forelimb‐buds revealed hyaluronic acid decreasing from 62% of total GAG at day 12 to 36% total GAG at day 16, whereas chondroitin sulfate increased from 34% to 58%. HA content of forelimb‐buds treated on day 12 was 22% greater than controls at 12 hours posttreatment, 45.5% at 24 hours posttreatment, returning to control levels at 60 hours after treatment. Chondroitin sulfate (CS) level decreased by 20% at 48 hours after treatment, returning to control level by 72 hours. Hyaluronate levels of HU 13 treated forelimb‐buds were 46% greater than controls at 24 hours after HU treatment, returning to control levels at 36 hours. CS levels were significantly lower than controls at 36 hours posttreatment. Histochemical analysis was performed to localize these alterations in GAG composition within the forelimbs. Beginning 12 hours posttreatment and continuing until 48 hours, an increase in HA content was observed in the mesenchymal compartment of the forelimb (1) beneath the apical ectodermal ridge and (2) between the ectoderm and prechondrogenic blastema (peripheral zone). This HA increase may be interpreted as a recovery (repair) phase of the pathogenesis of the HU malformation. To confirm that this shift in GAG is indicative of a compensatory phenomenon mitotic indices of the forelimbs were examined. At 36 hours posttreatment substantial increase in mitotic activity was observed in the subridge and peripheral regions of forelimbs treated on day 12, whereas those treated on day 13 demonstrated a significant increase only in the subridge zone. The increase in HA composition in the zones of the forelimb correlated well with the increase of mitotic activity. It is suggested that elevated HA/CS ratio allowed for increased proliferation and reorganization of the mesenchymal cell population, whereas the return to control levels marked the cessation of repair and resumption of differentiation.
Growth characteristics of the murine trisomy 19 thymus
Authors: Bersu Edward T. , Crandall Clare , White Beverly J. 
Published: June 2005

AbstractDevelopment of the trisomy 19 mouse thymus was studied by (1) evaluation of cell and nuclear counts and volume distributions and (2) examination of the in vivo cell cycle characteristics using flow cytometry. Direct preparations of thymuses from affected animals and their normal littermates at 17, 18, 19 gestational days, and at term were used. Cell numbers in aliquots from the trisomic thymus suspensions were always significantly less than those in the normal animals. There were no differences in cellular or nuclear volumes between the two groups. However, the populations of cells in the trisomic suspensions showed a lag in the normally occurring transition from a larger to a smaller size. DNA distribution histograms from these suspensions were generated using a TPS‐1 Cell Sorter, and percentages of cells in different phases of the cell cycle were estimated using computer analysis. The resulting graphs and numerical data from the trisomic mice, when compared with the normals, showed consistent increases in the relative numbers of cells in the S and G2 + M phases of the cell cycle. Because growth retardation is a major feature of trisomy 19, as well as in other murine trisomies, these results suggest that cell cycle alterations may, in part, contribute to the reduced cell number, delayed development, and smaller size of the trisomic animals.