bluuebunny/crossref_metadata_2025 huggingface dataset:
Congenital Hydrocephalus: Role of Transplacental Myxovirus Infection
Authors: TAKANO Tomoyuki , UNO Masaaki , YAMANO Tsunekazu , SHIMADA Morimi
Published: May 2008

The definite etiology in most cases of congenital hydrocephalus still remains unknown. Many studies have been reported on the experimental hydrocephalus induced by viral infection other than TORCH (Toxoplasma, Other agents, Rubella virus, Cytomegalovirus and Herpes simplex type 1 and 2 viruses). Above all mumps virus induces a high frequency of hydrocephalus. Several pediatric cases of hydrocephalus after mumps virus infection have been reported. These cases are thought to be caused by ependymitis due to mumps virus infection. Clinical cases of congenital hydrocephalus possibly caused by intrauterine mumps or influenza virus infection are also accumulating. The definitive evidence of a teratogenic potential for mumps and influenza virus, however, has been obscure yet. Our experimental studies demonstrated that mumps and parainfluenza virus type 3 could induce hydrocephalus by destructive ependymal infection in suckling hamsters. However, the transplacental infection of these viruses was rare. These results show that myxoviruses such as mumps and parainfluenza virus have a strong affinity to ependymal cells, and then they cause resultant ependymal destruction. We suggest that when the placenta is impaired so severely that these viruses are able to pass through the placental barrier, maternal infection would cause the hydrocephalus to the infant.
Inborn Errors of Peroxisome Biogenesis and Brain Malformation: Clinical and Biochemical Studies*
Authors: SUZUKI Yasuyuki , SHIMOZAWA Nobuyuki , ORII Tadao
Published: May 2008

Zellweger's cerebro‐hepato‐renal syndrome is characterized by the absence of peroxisomes, severe neurologic manifestations, and neuropathological findings such as polymicrogyria and neuronal heterotopia which are based on disturbances of neuronal migration. We investigated the pathogenesis of peroxisome‐deficient disorders in attempts to clarify the molecular basis of these brain dysgenesis. Complementation analysis revealed that at least 9 genes contribute to the formation of peroxisomes. One of these gene products, peroxisome assembly factor‐1 (PAF‐1), was isolated, using a functional cloning method and a mutant Chinese hamster ovary cell line with defective peroxisomes. PAF‐1 restored the peroxisomes and biochemical abnormalities in fibroblasts from patients with Zellweger syndrome and who belonged to complementation group F. Defects in PAF‐1 would result in dysfunction of peroxisomal membrane or in the transport machinery of peroxisomal proteins, and metabolic disturbances such as accumulation of very long chain fatty acids and defects in plasmalogen may occur.
Retinoids and Retinoid Receptors in Teratogenesis*
Authors: KOCHHAR Devendra M.
Published: May 2008

There is overwhelming evidence that vitamin A (retinol), presumably through its metabolite retinoic acid, participates in organogenesis at several stages and sites during normal development. Besides the important role of retinol and retinoic acid (RA) as micronutrients in growth and development, these retinoids and their synthetic analogs are now viewed as drugs for treatment of oncologic and dermatologic diseases. An excess of vitamin A, RA, or several other synthetic analogs are teratogenic. Mechanisms involved in teratogenesis remain unsolved but are under active investigation in many laboratories. The attention has recently focused on a series of endogenous proteins which serve as nuclear receptors for natural retinoids as means to discover how retinoids intervene in diverse cellular functions and which of their cellular and molecular targets are crucial to the developing embryo. There are two classes of receptors, termed retinoic acid receptors (RARs) and retinoid X receptors (RXRs). This brief review summarizes the results of our recent studies which suggest that: 1) the teratologic effects of retinoids are mediated by the nuclear receptors; 2) the heterodimer RXR/RAR pathway is the major mechanism for the induction of teratogenesis; 3) RXR‐selective synthetic retinoids have diminished teratogenicity; and 4) an overexpression of specific RARs in response to RA disrupt skeletal morphogenesis resulting in limb reduction defects.
Teratogenic Characteristics by Single Dosing of Antineoplastic Platinum Complexes in Rats
Authors: MURANAKA Ri‐ichi , FUKIISHI Yonetaka , TSUIKI Hisashi , HASEGAWA Yasuhiko
Published: May 2008

We investigated the embryolethality and teratogenicity of a new platinum complex, 254‐S, and cisplatin (CDDP) by single dosing to dams on one day during the period of organogenesis. The results are summarized as follows: (1) Embryolethality was maximal after 254‐S treatment on day 7 of gestation (Day 7) and after CDDP treatment on Days 6 to 9. It decreased with advancing gestational age. (2) Both 254‐S and CDDP were teratogenic. The critical period for induction of malformation appeared twice for 254‐S, at Days 6 to 9 and at Days 14 to 15, and once for CDDP, at Days 5 to 8. (3) The types of malformations induced by 254‐S or CDDP were different, indicating different mode of teratogenesis. 254‐S caused malformations mainly in the craniofacial or limb bud areas in the biphasic manner, whereas CDDP caused malformations mainly of the limb buds in the monophasic manner. (4) Malformations of the limb/digit and tail that are known to have critical periods during the late stage of organogenesis were induced by treatment with 254‐S on Day 7 and with CDDP on Day 5 or 6.
Vasoactive Intestinal Polypeptide‐containing Neurons and Processes in the Developing Hippocampus of Rats Prenatally Exposed to Methylazoxymethanol Acetate
Authors: FUNAHASHI Atsushi
Published: May 2008

Developmental alteration of the dendritic arborization and axonal boutons of vasoactive intestinal polypeptide (VIP) neurons in the CA1 hippocampus was immunohistochemically examined in both control and microcephalic rats at postnatal days 15 and 60. Microcephaly was induced by prenatal exposure to methylazoxymethanol acetate (MAM; 20 mg/kg) on day 15 of gestation (MAM rats). In the control at postnatal day 15, VIP‐immunoreactive axonal boutons were densely aggregated specifically in the stratum pyramidale. At postnatal day 60, these axonal boutons in the stratum pyramidale of the controls were somewhat less dense. Another aggregation of axonal boutons was also observed along the upper part of the stratum oriens near the alveus border (area A). In the MAM rats at postnatal day 15, on the other hand, VIP‐immunoreactive neurons in the CA1 hippocampus were decreased in number and the dendritic arborization of these neurons was very poor compared with the controls. The density of VIP‐immunoreactive axonal boutons was remarkably lower than the controls. In the MAM‐rats at postnatal day 60, density of the axonal boutons was almost similar with that of MAM‐rats at postnatal day 15 in the stratum pyramidale, whereas a drastic increase was observed in area A, which made the bouton aggregation more dense than in the controls at postnatal day 60. These observations suggest that there is an area‐dependent difference in the development of VIP neurons in the CA1 hippocampus which may be related to the area‐dependent heterogeneous vulnerability of VIP neurons to MAM exposure.
Incidence and Familial Occurrence of the Congenital Anomalies of the Face, Hand and Foot
Authors: OKA Ichiro , NATSUI Makoto , GOTO Takahiro , KAMIYA Noriaki , YAMADA Atsushi , FUJITA Shinya
Published: May 2008

We made an epidemiological study of congenital anomalies of the face, hand and foot in newborns from 1973 to 1992 in Miyagi Prefecture which has a population of about two million. In these twenty years 579,766 babies were born in Miyagi Prefecture. Out of these newborns 3,416 babies with 3,759 congenital anomalies of the face, hand and foot were registered. Of all registered congenital anomalies, face anomalies were most commonly encountered, followed by hand and foot anomalies. Among face anomalies, in order of frequency, accessory ear was the most common, next cleft lip with or without cleft palate, cleft palate alone, cryptotia and microtia. The occurrence ratio per 10,000 live births was 9.6 in accessory ear, 6.7 in cleft lip, 6.1 in cleft lip with cleft palate, 4.2 in cleft palate alone, 2.9 in cryptotia, and 1.8 in microtia. In hand and foot anomalies, polydactyly was the most common and syndactyly the next. Incidence ratio of polydactyly was 5.8 in the hand and 6.4 in the foot. Polydactyly was the most frequent in the preaxial ray in the hand and in the postaxial ray in the foot. About half of cases of postaxial polydactyly the foot was associated with syndactyly between the fourth and fifth toe. In addition, we reported on variation of the incidence ratio and familial occurrence of congenital anomalies of the face, hand and foot.
Functional Damage in the Developing Brain Induced by Maternal Environmental Agents: Ethanol, Tobacco and Low‐Copper Level
Authors: TANAKA Harumi
Published: May 2008

To evaluate tests for behavioral teratology in animals, brain dysfunction caused by maternal environmental agents is compared both epidemiologically and experimentally. Ethanol: The features of CNS involvement in human FAS (fetal alcohol syndrome) and FAE (fetal alcohol effects) are developmental delay and intellectual impairment. One of the most vulnerable structures in the rat fetus exposed to ethanol in utero is the synaptic formation in the hippocampus. What test for brain dysfunctions, such as deficits in learning, inhibition and attention, is there? Tobacco: Thirty‐three percent of human FTS (fetal tobacco syndrome) cases have CNS involvement, which is characterized by developmental delay, and behavioral problems such as a short attention span and hyperactivity. As to the concomitant effects of ethanol and tobacco on human offspring, CNS involvement appeared to be most specific for alcohol exposure, but was also observed slightly with smoking without drinking. How can the effects of concomitant substances be discriminated in an animal test? Low‐copper level in brain: Related to the development of their offspring, abnormal movements in brindled mutant mouse heterozygotes are observed. These findings may be influenced by both copper and oxygen radical metabolism. The teratogenic effects of triethylene tetramine dihydrochloride, a chelating drug for copper on the fetal mouse brain are noted both grossly and microscopically. How can the abnormal CNS development in relation to a certain biochemical mechanism be detected by means of an animal test? In conclusion, to examine behavioral teratology in animals, specificity and accuracy should be considered in comparison with in humans.
The Timing of Appearance of Ossification Centers of Carpal and Tarsal Bones in Mouse Newborns
Authors: CHIBA Katsushi , RAHMAN Mohammed E. , ISHIKAWA Hitoshi , ENDO Akira
Published: May 2008

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.
Effects of Bis‐diamine to Cardiac Mesenchymal Cell Migration of the Chick Embryo
Authors: SUMIDA Hiroshi , NAKAMURA Harukazu , MATSUO Tatsuhiro , YASUDA Mineo
Published: May 2008

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 μg of bis‐diamine dissolved in 50 μl 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% formaldehyde. 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 cushion in chicks. This portionally different effect of bis‐diamine can explain that bis‐diamine does not frequently induce endocardial cushion defects in chicks.
Maldevelopment of Early Chick Embryos Induced by NonThermogenic Dose Radio Frequency Radiation at 428 MHz for the First 48 Hours
Authors: SAITO Kenichi , SUZUKI Katsushi
Published: May 2008

ABSTRACT Exposure of developing chick embryos to non‐thermogenic dose of 428 MHz radio frequency (RF) have been reported to cause embryo lethality, teratogenicity and delayed hatching (Saito et al., 1991). To elucidate the mechanisms of such adverse biological effects, developing chick embryos were exposed to 428 MHz RF at 5.5 mW/cm2 for the first 48 hrs of incubation. Ten fertilized eggs were used in each experiment; exposure and sham‐exposure were alternatively repeated 10 times. Embryos were examined on viability, then excised, fixed in alcohol and examined morphologically on the developing status. Some embryos were subjected to histological study. In the exposed group, embryos were alive but the development was severely delayed. The average number of somites was 10.5±2.8 SD in the exposed group and 13.1 ± 2.3 in the control, respectively. Embryos with less than 10 somites were about 27% in the exposed group. The munimum number of somites was 3 in the exposed group and 7 in the control. Developmental delay was about 6 to 16 hrs in terms of Hamburger‐Hamilton stage. Two cases of duplication anomalies were detected at positions in the incubator with severely affected corresponded to those with high embryo lethality in our previous study. Histological observations suggested developmental delay might not be due to direct cytotoxicity but to the slower cell proliferation and/or to disturbances of cell‐cell interaction, migration and orientation. The possibility that non‐thermogenic RF electromagnetic field may affect early embryogenesis indirectly through physico‐chemical modifications of metal‐containing proteins are discussesd.
Sex Differences in the Rat Brain: A Procedure for Estimating Developmental Toxicity
Authors: Sumida Hiroyuki , Moriya Tokuharu , Handa Jun , Yamashita Takumi , Nakamori Kouta , Nishizuka Masako , Arai Yasumasa
Published: May 2008

The sexually dimorphic nucleus of the preoptic area (SDN‐POA) and the anteroventral periventricular nucleus of the preoptic area (AVPvN‐POA) are sexually dimorphic regions in the rat brain. These regions are sensitive to reproductive function‐related drugs, and thus applied for aromatase inhibitor evaluation in the present study. Effects of NKS01 (an aromatase inhibitor) and tamoxifen on the SDN‐POA and AVPvN‐POA were examined. Five mg of NKS01 or its vehicle was injected to SD male and female rats from days 1 to 14 (the day of birth = day 0). Other 10 males and 10 females received a single injection of 100 μg tamoxifen on day 1. Rats in each group were sacrificed at day 30 or 60. The SDN‐POA was examined at days 30 and 60, and the AVPvN‐POA at day 60. When NKS01 was given to male rats for the first 14 days of life, a significant reduction of SDN‐POA size was observed on day 60. When tamoxifen was given, SDN‐POA reduction in size was also observed at days 30 and 60 in male rats. As for the AVPvN‐POA, tamoxifen markedly reduced volume in female rats, resulting in polycystic ovaries at day 60. This may be due to an estrogenic property of tamoxifen. On the other hand, NKS01 was not significantly effective in the AVPvN‐POA, although the volume of the nucleus in NKS01 males was inclined to increase. From these results, as well as the SDN‐POA, the AVPvN‐POA may be useful to evaluate the side effect of reproductive function‐related drug.
Visualization of Intracranial Structures in Early Human Embryos using 3‐D Computer Graphics Technique
Authors: SOARES Sergio BRANCO , OHATA Kenji , HAKUBA Akira , NAKATSU Tomoko , UWABE Chigako , SHIOTA Kohei
Published: May 2008

In classic human embryology, one of the most important techniques to observe embryonic structures three‐dimensionally (3‐D) was to reconstruct embryos or their parts using wax plate models from serial histological sections. However, wax plate reconstruction does not allow observation of internal structures and lumens unless the models are cut after reconstruction. The development of computer graphics has enabled us to reconstruct various biologic structures on the viewing screen and to manipulate the computer images as freely as we desire. Nevertheless, until now computer reconstruction has not been used frequently to study human organogenesis. We reviewed and photographed serial histological sections of early human embryos, projected these photographed slides onto a screen and traced the outlines of specific structures under study on a digitizing pad that was interfaced with a 16 bit computer. The digitized images were combined using a software for 3‐D reconstruction. With this technique, we were able to visualize the anatomical localization and interrelation of various structures inside the human head during the embryonic period. The 3‐D reconstruction technique should be of potential use for the study of normal and abnormal morphogenesis.
Congenital Anomalies in Singapore
Authors: TAN K. L. , CHIA H. P.
Published: May 2008

Abstract A 3‐year study (Jan. 1986‐Dec. 1988) in the Kandang Kerbau Hospital revealed 678 infants with birth defects in 44,842 livebirths, (15.13 per 1,000 live births, 95% confidence intervals, CI 14.0–16.2). There were 161 cases with musculoskeletal abnormalities (3.5 per 1,000, 95% CI 3.06‐4.19), 111 gastrointestinal system malformations (2.47 per 1,000, 95% CI 2.04‐2.58), 88 chromosomal abnormalities (1.96 per 1,000, 95% CI 1.57‐2.42), 78 cardiovascular system abnormalities (1.74 per 1,000, 95% CI 1.38‐2.17), 73 urogenital system defects (1.63 per 1,000, 95% CI 1.28‐2.05), and 52 central nervous system defects (1.16 per 1,000, 95% CI 0.87‐1.52). The prevalence of cleft lip, cleft palate, and cleft lip/palate was 1.72 per 1,000, and Down's Syndrome 1 in 700. At review, six weeks later, the false positive rate was 4% in the infants with defects, and in the group of 709 normal controls (matched by race, maternal age, ward class and time/date of birth), the false negative rate was 0.84%.

The strongest risk factors were a family history of birth defects (odds ratio, OR 3.3, 95% CI 1.8‐6.4), and previous abnormal sibling(s) (OR 2.4, 95% CI 1.1–5.3). Other risk factors included drug intake during pregnancy (OR 1.2, 95% CI 0.8‐2.0), becoming significant with ingestion during the first trimester (OR 1.4, 95% CI 1.1‐1.8). Traditional medicine (mainly Chinese herbs during pregnancy) had a slightly higher risk (OR 1.4, 95% CI 1.0–2.0).

The National University Hospital keeps a register of birth defects; trained nurses interview all mothers using a set questionnaire. Evaluation of 11,460 livebirths over a 3‐year period (1991–1993) revealed 472 cases (41.19 per 1,000 livebirths, 95% CI 37.48‐44.90) with 171 musculoskeletal defects (14.92 per 1,000 livebirths, 95% CI 12.69‐17.16), 105 cardiovascular defects (9.16 per 1,000, 95% CI 7.41‐10.91), 64 urogenital defects (5.58 per 1,000, 95% CI 4.22‐6.95), 30 gastrointestinal defects (2.62 per 1000, 95% CI 1.68‐3.55), 35 mixed system defects (3.06 per 1,000, 95% CI 2.04‐4.07), and 18 chromosomal abnormalities (1.57 per 1,000, 95% CI 0.85‐2.30). The prevalence of cleft lip/cleft lip and palate was 1.48 per 1,000. This higher prevalence could be due to the present practice of routine screening of every infant on the first day of life, together with a careful assessment for musculoskeletal defects, especially congenital dislocation of the hips.
Congenital Infection and Disorders of Brain Development: With Special Reference to Congenital Cytomegalovirus Infection
Authors: TSUTSUI Yoshihiro , KOSUGI Isao , SHINMURA Yuichiro , NAGAHAMA Masato
Published: May 2008

ABSTRACT Intrauterine infections of various microorganisms have the potential to induce brain abnormalities in the fetus and newborn infant. Among the infectious pathogens, cytomegalovirus (CMV) is the most significant infectious cause of brain abnormalities, with variations from fatal cytomegalic inclusion disease to functional brain disorders, such as mental retardation or epilepsy. Here, we present three autopsy cases of congenital CMV infection, and we review the features of the brain abnormalities of congenital CMV infection. A ventriculofugal spread of infection seems to be characteristics of congenital CMV‐infected brains and is suggested to be the cause of neuronal migration disorders, resulting in brain malformations, such as microcephaly, lissencephaly and polymicrogyria. We also present an experimental animal model for congenital CMV infection. With the model we showed that murine cytomegalovirus (MCMV) infection in the developing mouse brain caused a disturbance of neuronal migration and neuronal cell loss, detected with morphometric measurements by labeling the neuronal precursor cells with BrdU. As shown by immunohistochemical double staining of BrdU and viral‐antigen, infected neuronal cells constituted only a part of the disordered neuronal cells, suggesting that an indirect effect of vital infection on neuronal cells also contributes the migration disorders presumably mediated by cytokines or the induction of apoptosis. Neuronal migration disorders caused by MCMV infection are also discussed with reference to those caused by X‐irradiation.
Treatment of Mouse Preimplantation Embryos with Adriamycin, Methyl Methanesulfonate and Retinoic Acid Results in Congenital Defects
Authors: NAGAO Tetsuji , SHIROTA Mariko , SATO Masako
Published: May 2008

ABSTRACT Treatment of mouse preimplantation embryos with adriamycin (ADM), methyl methanesulfonate (MMS) and all‐trans retinoic acid (RA) on their later development including implantation, growth and organogenesis were investigated. ICR mice were treated intraperitoneally with ADM or MMS on day 3 of gestation, or with RA on day 4 of gestation. The uterine contents were examined on day 18 of gestation. The viable fetuses were inspected for external and skeletal malformations. Irrespective of the kind of chemical agents tested, frequencies of total malformed fetuses were significantly increased, whereas the frequencies were considerably lower than those of malformations in fetuses of dams treated with ADM, MMS or RA during the period of organogenesis. In the fetuses of ADM‐treated mice, the most common abnormality was umbilical hernia, followed by cleft palate. In the MMS‐treated fetuses, the most common abnormality was cleft palate. Among the malformations observed in this study, duplication of hindlimb (5/193 fetuses) induced by the treatment with RA at the preimplantation stage was a quite unique abnormality. This type of malformation has never before been found in our historical control embryos and in embryos treated with various kind of teratogens. Based on these results and other data, it is concluded that embryos at the preimplantation stage are susceptible to environmental chemical‐induced congenital malformations.
Development and Disappearance of Wavy Ribs Caused by Azose‐mide in the Mouse Fetus
Authors: KUMAZAWA Toshihiko , KATO Tatsuma , HAYASAKA Ikuo
Published: May 2008

ABSTRACT Treatment of gravid mice (day 13 of gestation) with azosemide induces wavy ribs in their fetuses. The present study examined the morphological sequence of azosemide‐induced wavy ribs, from their appearance through disappearance, by means of cartilage‐bone double stain, hematoxylin and eosin stain, von Kóssa's stain for calcium salts and alkaline phosphatase stain. Both endochondral and intramembranous ossifications of the ribs were inhibited in day 14 azosemide‐treated fetuses. A curvature of the ribs occurred on day 15 of gestation, and excessive uncalcified osteoid was present on the outer surfaces of the bent region. In the region of curvature, endochondral and intramembranous ossification, which is remarkable in normal, was not observed. Calcification, which began on day 14 in untreated fetuses, started including the bent region on day 16 of gestation. However, ribs in azosemide‐treated fetuses exhibited alkaline phosphatase activity like in the control, during days 14–16 of gestation. These observations suggest that the defective ossification in azosemide‐treated fetuses is caused by inhibition of calcium salts deposition on the uncalcified osteoid. During the lactation period, the bend of ribs was gradually normalized, and the bend was disappeared on day 9 postpartum.
Anomalies of Cartilaginous and Ossified Axial Skeleton in Rat Fetuses Treated with Cyclophosphamide: Type, Frequency, and Stage Specificity
Authors: IGARASHI Eiki
Published: May 2008

The purpose of the present study was to assess the type, frequency and stage specificity of axial skeletal anomalies induced by cyclophosphamide (CP). Female Crj: Wistar rats were mated with male rats (vaginal sperm = gestation day 0, GDO). They were then injected intravenously with 5 mg/kg of CP in a saline solution on GD7, 8, 9, 10, 11, 12, 13, or 14, or with saline on GD8 for controls. Dams were sacrificed on GD20. Fetuses were stained with alcian blue and alizarin red S. Eighteen types of axial skeletal anomaly were detected, e. g., shifted ventral lamina, cervical rib, cleft arch of the atlas, axis fused to atlas, sternebral misalignment, bipartite sternum, fused ribs, change in pre‐sacral vertebral number, supernumerary rib, misdirected transverse process, anteriorly‐shifted spinous process, short spinous process, fused vertebral bodies, cartilaginous short rib at Th.7, short or absent rib at Th.12 or 13, dumbbell‐shaped vertebral body, wavy rib, and rib cartilage not attached to the sternal cartilage. The present experimental study indicates that: 1) observations of cartilaginous skeletons can provide more information than observations of ossified skeletons; 2) the pattern of CP‐induced anomalies along the anterior–posterior axis may depend on the sequence of development progression among structures, spinous process, vertebral arch, vertebral body, rib/transverse process; and 3) in more cranial vertebrae, anteriorly‐shifted anomalies, such as anteriorly‐shifted ventral lamina and anteriorly‐shifted spinous processes, rather than posteriorly‐shifted anomalies, may be the primary indicators for detecting developmental toxicity, since CP injection increased the frequencies of these anomalies.
Variant Patterns of Palatal Rugae Induced by Chemicals in Mouse Fetuses
Authors: YASUDA Mineo , HORIE Shigeaki , MATSUI Kohji A. , TAKAGI Toshio N. , YAMASHITA Keisuke
Published: May 2008

The oral surface of the mouse palate has eight or nine pairs of transverse ridges, or rugae. We have reported that various teratogens induce abnormal patterns of palatal rugae in mice. In the present note, we show examples of palatal ruga anomalies induced by several teratogens in mouse fetuses near term. Defined variant patterns are supernumerary, division, lateral or medial bifurcation, short, maldirection, cross, modified cross, lateral or medial fusion, lateral or medial bifurcation, median fusion, median division, and numerical reduction. In some cases naming of observed variants may be difficult, but differential diagnosis between variations in the “normal” range and “anomalous” variants seems rather easy.
Effects of Restrained Fetal Movement on the Development of the Rat Hip Joint
Authors: KIHARA Isao , HASHIMOTO Ryuju , OTANI Hiroki
Published: May 2008

ABSTRACT

The effect of fetal movement on the development of the hip joint was examined by restraining the leg movement using exo utero operation in rat fetuses. At embryonic day (E) 16.5, when the hip joint cavity starts to form, one side of the hind limb was sutured onto the embryonic membrane. After exo utero development to E18.5, the hip joint of the operated side was compared morphologically with those of the unoperated side, sham‐operated and unoperated in utero controls. The largest diameter of the femoral head (FH) and the gross morphology of the joint cavity of the operated side was not different from those of controls. By light microscopy (LM), the surface of the control E18.5 FH and acetabulum was smooth and covered by thin scale‐shaped cells which were partially pyknotic, and oval‐shaped cells underneath were rather regularly arranged in a thickness of a few cells. By transmission electron microscopy (TEM), scale‐shaped cells covered the FH surface incompletely, and the spaces in‐between were filled with the intercellular matrix. Oval‐shaped cells underneath had well developed rough endoplasmic reticulums. By scanning electron microscopy (SEM), mounds and grooves on the FH surface were evident at E17.0 but became unclear at E18.5. Subsurface collagen fibers formed a coarse meshwork at E17.0 but formed bundles at E18.5. On the operated side, by LM, the surface of the FH and acetabulum was irregular and lined by spindle‐shaped cells, whereas the underlying mesenchymal cells also showed an irregular cell shape and arrangement. By TEM, collagen fibrils in intercellular spaces were dense but did not generally form bundles. By SEM, the FH surface was rugged with banks and subsurface collagen fibers did not form bundles but remained as a dense meshwork. These results suggest that the fetal hind limb movement influences development of the surface structure of the FH and acetabulum and that this system may be useful to study prenatal etiology of the congenital dislocation of the hip.
Preimplantation Diagnosis: Basic Science and Clinical Practice
Authors: DELHANTY Joy D. A.
Published: May 2008

Abstract Preimplantation genetic diagnosis (PGD) was first carried out in the UK, at the Hammersmith Hospital, in 1989. Since then almost 100 babies have been born worldwide following PGD with no reported increase in congenital anomalies. This overview will consider the types of patients coming forward for the procedure, approaches to single cell diagnosis and the technical difficulties that have become apparent.
A Population‐based Case‐Control Teratological Study of Three Parenteral Penicillins G
Authors: CZEIZEL A.E. , ROCKENBAUER M. , SøRENSEN H.T. , OLSEN J.
Published: May 2008

The purpose of the study was to check the human teratogenic potential of three penicillins G: parenteral treatments with benzylpenicillin, benzylpenicillin‐procaine, and benzylpenicillin + benzylpenicillin‐procaine during pregnancy in the population‐based dataset of the Hungarian Case‐Control Surveillance of Congenital Abnormalities, 1980–1996. Of 38,151 pregnant women who had babies without any defects (population control group), 303 (0.8%) were treated with penicillin G. Of 22,865 pregnant women who had offspring with congenital abnormalities, 236 (1.O%) were treated with penicillin G (crude OR with 95% CI = 1.3, 1.1–1.5). Of 812 mothers who deliveried babies affected with Down syndrome (patient controls), 15 (1.8%) had penicillin G treatment, and this rate exceeded significantly the figure of both the case and population control groups. This finding needs further studies. The case‐control pair analysis did not indicate a teratogenic risk of three parenteral penicillin G treatments during the second‐third months of gestation, i.e., in the critical period for major congenital abnormalities. The lower use of penicillins G was explained mainly by recall bias in the population control group. Thus, parenteral penicillin G treatments during pregnancy do not present a detectable teratogenic risk to the fetus.
Similarities and Differences in Reproductive Endocrinology Between Non‐Human Primates and Humans
Authors: YOSHIDA Takashi
Published: May 2008

Similarity in reproductive functions between non‐human primates and humans makes non‐human primates generally serve as better experimental animals in reproductive researches. Cynomolgus monkeys show such similarity in their menstrual cycle patterns of serum luteinizing hormone (LH), follicle‐stimulating hormones (FSH), and sex steroid hormones. Although similarities include significant increase in serum estradiol (E2) concentrations just before ovulation, cynomolgus monkeys differ in their negligible increase in E2 and single increase in progesterone (P) during the luteal phase. Unique to humans and great apes (e.g., gorillas and chimpanzees) are apparently biphasic patterns in serum E2 concentrations at the periovulatory period and at the luteal phase and synchronous increases in serum concentrations of P with E2 at the luteal phase. Although humans and non‐human primates differ in their secretory activity of steroid hormones from the functional corpus luteum, they share the same controlling mechanism of the function of the corpus luteum by LH, based on our analysis of the LH‐receptor characteristics throughout the menstrual cycle of cynomolgus monkeys. Although humans and cynomolgus monkeys show similarities in the fluctuation patterns of maternal serum concentrations of sex steroid hormones during the pregnancy period, they differ in the fluctuation patterns of protein hormones. For cynomolgus monkeys, maternal serum concentrations of chorionic gonadotropin (CG) and somatomammotropin (i.e., placental lactogen, or CS) increase only in the first quarter of pregnancy. However, for humans, higher serum concentrations of those two hormones (CG and CS) are maintained throughout the entire pregnancy. Similarities and differences among non‐human primates and humans are discussed in this article.
An Embryotoxic/Teratogenic Potential and Abortifacient Effect Study of Interferon alfacon‐1 (Infergen®) via Subcutaneous Administration to Rhesus Monkeys
Authors: IHARA Toshio , ONEDA Satoru , YAMAMOTO Takashi , BOUDREL Lionel , LAU David , MILLER Dennis , NAGATA Ryoichi
Published: May 2008

Interferon alfacon‐1 (Infergen®, CIFN, r‐metIFN Con 1, hereunder interferon alfacon‐1) is a type I interferon currently used to treat patients infected with the hepatitis C virus. In order to assess the embryotoxic and teratogenic effects of interferon alfacon‐1, doses of 0, 1, 3 and 10 μg/kg/day were administered subcutaneously to pregnant rhesus monkeys daily from Day 20 to Day 50 of gestation.

No maternal deaths occurred, and no interferon alfacon‐1 related abnormalities were noted in general signs, body weight, food consumption or necropsy findings in any group. Abortions and embryonic deaths occurred in 4 out of the 10 dams of the 3 μg/kg/day group and 8 out of the 10 dams of the 10 μg/kg/day group between Days 25 and 62 of gestation. The concentrations of serum 17β‐estradiol and/or progesterone levels decreased before embryonic death in some, but not all monkeys in the 3 and 10 μg/kg/day groups. Microscopic changes to the uterus and placenta in the dams that experienced embryonic/fetal cardiac arrest included hemorrhage and necrosis in the chorionic villi, hemorrhage in the uterine gland, granular leukocyte infiltration, hemorrhage and/or thrombus in the endometrium.

In the surviving fetuses, no test article related abnormalities were observed in body weight. placental weight, external measurements, organ weights, external, placental, visceral or skeletal findings.

The mean serum concentration of interferon alfacon‐1 at 10 μg/kg/day was consistent with previous pharmacokinetic data in non‐pregnant rhesus monkeys, suggesting that pregnancy does not greatly alter the pharmacokinetics of interferon alfacon‐1. Antibodies to interferon alfacon‐1 were first detected on Day 40 of gestation in all groups receiving the drug. It was concluded that the non‐toxic maternal dose level of interferon alfacon‐1 is 10 μg/kg/day. Doses of interferon alfacon‐1 of 3 and 10 μg/kg/day were associated with an increase in abortion/embryonic death rate, but 1 μg/kg/day did not result in any effect on the fetus. No teratogenic or growth retardation effect from interferon alfacon‐1 was observed in the surviving fetuses at 10 μg/kg/day.
Orthodontic Morphological Evaluation of Treacher Collins Syndrome
Authors: UMEMURA Sachio
Published: May 2008

To establish a treatment for Treacher Collins syndrome, the maxillocraniofacial morphology was quantitatively evaluated by means of cephalometric radiography and the following results were obtained.

1. The cranial base showed a small value of S‐ER’(length of sphenoid bone in anterior cranial base), S‐SOS’(length of sphenoid bone in posterior cranial base) and S‐Ba (length of posterior cranial base) in addition to similarly reduced NSBa, indicating undergrowth of the the cranial base as well.

2. Though the orbit had large BIOD and BIOD/W with ocular hypertelorism, no abnormal finding was obtained in the antero‐posterior positioning of the orbit in the skull.

3. In the maxillary region, the maxilla showed undergrowth but no abnormal finding was recorded on the vertical and antero‐posterior positioning of the mandible.

4. The mandible showed undergrowth with a wide mandibular angle.

In conclusion, the morphology evaluated quantitatively in patients with Treacher Collins syndrome varied considerably. Therefore, it was considered essential to evaluate the morphology accurately for treating this syndrome including surgery and orthodontic treatment.
Reproductive Effects of Early Neonatal Exposure to Diethylstilbestrol or Tamoxifen in Rats
Authors: KUWAGATA Makiko , SAITO Yoshiaki , YOSHIMURA Shinsuke , NAGAO Tetsuji
Published: May 2008

To evaluate the effects of potential estrogenic or anti‐estrogenic compounds on reproduction, male and female Sprague‐Dawley rats were injected subcutaneously with 50 μg/kg diethylstilbestrol (DES) or 20 mg/kg tamoxifen (TAM) from postnatal day 1 to 5. Growth, estrous cycle, locomotor activity, and reproductive function including masculine sexual behavior, sperm motion, and development of reproductive organs were examined. Decrease in body weight gain and abnormal estrous cycle, such as persistent estrous, or prolonged estrous cycle were observed following early neonatal exposure to DES or TAM, while there was no effect on locomotor activity evaluated in the open field in the DES‐or TAM‐treated group. A marked decrease in sperm motility was found in the TAM‐treated group. Anatomical and histological alterations of reproductive organs were observed in male and female rats in the DES‐treated group and in female rats in the TAM‐treated group. Early neonatal exposure to DES or TAM affected the masculine sexual behavior, resulting in a marked decrease in the ability to copulate and in fertility. In matings of the DES‐or TAM‐treated rats and intact rats, none of the treated females copulated successfully, whereas approximately 30% of treated males showed normal fertility. These results suggested that early neonatal exposure to DES or TAM induced more marked reproductive dysfunction after puberty in females than in males.
Male‐Mediated Developmental Toxicity: Enhanced Susceptibility to Induced Teratogenesis in the Offspring of Male Mice Treated with Ethylnitrosourea
Authors: NAGAO Tetsuji
Published: May 2008

Male ICR strain mice were injected intraperitoneally with ENU at 50 mg/kg daily for 5 days and mated to untreated virgin females of the same strain on days 64–80 after the last dose. Copulations during this period involved spermatogonial stem cells at the time of the last treatment. Subsequently, copulated females were injected intraperitoneally with ENU at 25–100 mg/kg on day 8 of gestation, at 50–200 mg/kg on day 12 of gestation or injected subcutaneously with triamcinolone acetonide at 1.25–10 mg/kg on day 12 of gestation. The uterine contents were examined on day 18 of gestation. Fetuses of dams treated on day 8 of gestation were inspected for external and skeletal abnormalities, and those of dams treated on day 12 were inspected for external abnormalities including cleft palate. Frequencies of microphthalmia and cleft palate in the group in which females mated with ENU‐treated males were treated with ENU at 50 mg/kg on day 8 of gestation or with ENU at 50 mg/kg on day 12 of gestation, respectively, were significantly higher than those in the group in which females mated with phosphate buffer‐treated males were treated with ENU at 50 mg/kg on day 8 or at 50 mg/kg on day 12. No significant increases in the frequency of cleft palate were observed in the groups in which females mated with ENU‐treated males were treated with triamcinolone acetonide on day 12 of gestation as compared with groups in which females mated with phosphate buffer‐treated males were treated with triamcinolone acetonide on day 12 of gestation. These results suggested the increased susceptibility to induced teratogenesis (congenital malformations induced by exposure of embryo/fetus during gestation) in the offspring derived from paternal germ cells treated with the potent mutagen ENU, but not the non‐mutagen triamcinolone acetonide.
Mechanism of malsegregations at meiosis: premature centromere separation and precocious division in female Chinese hamsters stimulated with gonadotropic hormones
Authors: Sonta Shin‐ichi , Kondo Yuko , Suzumori Kaoru , Kawamoto Takayuki
Published: May 2008

ABSTRACT  Using female Chinese hamsters stimulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG), we investigated the influence of hormonal stimulation upon meiotic segregation in oocytes. In 1,576 oocytes ovulated spontaneously from 197 non‐treated mature females, the number (percentage) of hyperhaploid oocytes with more than 12 (12–14) chromosomes was 16 (1.0%). These cells had no extra single chromatids, but all had extra chromosomes. Single chromatids were seen in 7 (0.4%) cells with a haploid chromosome set. On the other hand, a total of 1,329 and 1,198 second meiotic (MII) oocytes from 64 mature females and 61 immature females stimulated with PMSG and hCG, respectively, were subjected to chromosomal analysis. Single chromatids were seen in 34 (2.6%) and 62 (5.2%) of these oocytes, respectively. Since these chromatids were mostly paired and the sister chromatids existed near each other in many cells, they may have separated from some chromosomes of haploid cells. Compared with the non‐treated females, the frequency of cells with single chromatids was significantly greater in oocytes from both mature and immature females stimulated with PMSG and hCG. The number (percentage) of hyperhaploid cells from mature and immature PMSG‐hCG‐stimulated females, respectively, was 15 (1.1%) and 14 (1.2%), which was not significantly greater than that in non‐treated females. Most of these cells had extra whole chromosomes but one oocyte from mature females and one from immature females had an extra single chromatid. These findings indicate that such hormonal stimulation induces premature centromere separation in MII oocytes and precocious division at anaphase I, which can be assumed by the presence of MII cells with extra single chromatids. Considering that no or less hyperhaploid MII oocytes with an extra single chromatid were seen in oocytes from spontaneous ovulation and from artificial ovulation on hormonal stimulation, these findings suggest that the major mechanism of malsegregations at first meiotic (MI) division is not a precocious division but rather, errors such as nondisjunction of homologous chromosomes (dyads).
Acrania: an autopsy case and review of the literature
Authors: Shinmura Yuichiro , Tsutsui Yoshihiro , Nishiguchi Tomizo , Kobayashi Takao
Published: May 2008

ABSTRACT We report an autopsy case of acrania with a review of the literature. A 31‐year‐old woman was admitted in poor genaral condition and diagnosed as pregnant at the 26th week of gestation. The fetus was suspected to be anencephalic or hydrocephalic by ultrasonography. She delivered a stillbirth male baby at the 28th week of gestation. Autopsy showed the cranium lacked the cranial vault The scalp directly covered the hydrocephalic brain without calvaria. No cerebellum was found macroscopically. On histological examination, the thinned cerebral layer was composed of white matter‐like brain tissue with glial and ependymal cells. In the cerebral layer near the base of the skull, a few NSE‐positive neurons among many GFAP‐positive glial cells and oligodendrocyte‐like cells were observed. The choroid plexuses were observed inside the ependymal layers. The brain stem and the spinal cord were normally preserved with clusters of NSE‐positive neurons. Agnethia and horseshoe kidney were combined as malformations other than the brain. We reviewed 42 cases of acrania from the literature.
Neurulation in the human embryo revisited
Authors: Nakatsu Tomoko , Shiota Kohei
Published: May 2008

ABSTRACT It used to be widely accepted that neural tube closure in the human initiates at the level of the future neck and proceeds both cranially and caudally like zip fastener closing. This continuous closure model was recently challenged, and observation of human embryos at the neurulation stage revealed that the closure of the human neural tube initiates at multiple sites. Multi‐site closure of the neural tube has been observed in many other animal species, but the initiation sites and the process of neural tube closure are variable among species. Therefore we should be careful when extrapolating the data of normal and abnormal neurulation in laboratory animals to the human. Recent studies in mouse genetics and developmental biology have shown that neural tube defects are quite heterogeneous both etiologically and pathogenetically. Gene mutations responsible for human neural tube defects are largely unknown, but molecular studies of human cases of neural tube defects and their comparison with the mouse genome data should provide a molecular basis for human neural tube defects.