Vesicular swelling in the cervical region (VSC) is occasionally observed among human embryos around Carnegie stage (CS) 21. However, its mechanism and significance in fetal development are unclear. The present study aimed to analyze the relation of development of VSC with jugular lymph sac (JLS) formation. Serial histological sections that were digitalized from 14 embryos at CS20 and CS21 stored at the Kyoto Collection were used for the analysis. Subcutaneous edema and enlargement of the subarachnoid space were found to cause VSC. No obvious abnormalities in cranial regions that may be related to the VSC were detected on histological sections. Three-dimensional reconstructions revealed the following: (1) the JLS was located bilaterally at the levels between the 1 and 4 cervical vertebrae; (2) the JLS was pyramidal in shape; and (3) no severe deformity and/or malformation was found in all samples. The JLS was not connected to the subcutaneous tissue and subarachnoid space in all samples. The mean volume of the JLS increased nine-times from CS20 (0.02 mm in VSC (-) group) to CS21 (0.18 mm in VSC (-) group). The mean volume of the JLS was comparable between the VSC (-) and VSC (+) groups at both CS20 and CS21. A moderate correlation was observed between VSCd and the mean volume of the JLS in both groups at CS20 (R2=0.75) and CS21 (R2= 0.56). In conclusion, the dynamics of the lymphatic system at the cervical region may contribute to VSC observed around CS21. This article is protected by copyright. All rights reserved.
Examination of maternal plasma cell-free DNA (cfDNA) for noninvasive prenatal testing for fetal trisomy is a highly effective method for pregnant women at high risk. This can be also applied to fetal gender determination in female carriers of severe X-linked disease. Polymerase chain reaction (PCR) analysis is a relatively simpler and less expensive method of detecting Y chromosome-specific repeats (Y-specific PCR; YSP), but is limited by the risk of false-negative results. To address this, we have developed a combined strategy incorporating YSP and an estimation of the fetal DNA fraction. Multiplex PCR for 30 single nucleotide polymorphism (SNP) loci selected by high heterozygosity enables the robust detection of the fetal DNA fraction in cfDNA. The cfDNA sample is first subjected to YSP. When the YSP result is positive, the fetus is male and invasive testing for an X-linked mutation is then required. When the YSP result is negative, the cfDNA sample is analyzed using multiplex PCR. If fetal DNA is then found in the cfDNA, invasive testing is not then required. If the multiplex PCR analysis of cfDNA is negative for fetal DNA, the fetal gender cannot be determined and invasive testing is still required. Our technique provides a potentially effective procedure that can help to avoid unnecessary invasive prenatal testing in some female carriers of severe X-linked disease.
Non-bullous congenital ichthyosiform erythroderma (NCIE) is characterized by skin scaling with erythema. In this study, two Pakistani families with NCIE are genetically characterized through Whole Exome and Sanger sequencing to identify molecular basis of the disease. We identified a nonsense homozygous c.2026C>T mutation of ALOXE3, causing premature termination of the eLOX3 protein (p.Q676X). In silico studies predicted impaired enzymatic activity of the premature truncated eLOX3, leading to abnormal synthesis of specific hepoxilin derivatives, essential for epidermal barrier formation. It is the first ever study reporting homozygotes of p.Q676X mutation in ethnically distinct two Pakistani families; otherwise, heterozygotes of the said mutation have been reported in South Asian population only. Hence, mutation seems to be region-specific and may be useful for molecular diagnosis of NCIE. Moreover, our findings should help in genetic counseling and career screening.
In the last decades, the prevalence of gastroschisis (GS) has increased worldwide. The purpose of this study was to identify maternal risk factors explaining the described gain and to identify differences between GS and omphalocele (OC). A case-control design was used to compare GS (n = 36) and OC (n = 18) mothers to control group (CG; n = 30) matched for maternal age. Specialized questionnaires and mothers' prenatal records were used, and participants completed a structured interview. Focus was on medical history, changing nutrition, drug consumption, and external risk factors. The local ethics committee approved this study. GS mothers were significantly younger (mean 23.00; median 24; SD ±5) than OC (P = 0.007; mean 28.61; median 28, 19-41; SD ±5.1) and CG (P = 0.001; mean 30.77; median 31, SD ±6.2). Mothers with abdominal wall defects (AWD) ingested antibiotics more often (P = 0.008) than CG. Socioeconomic characteristics, for example, level of profession, of GS mothers was significantly lower than OC (P = 0.039) and CG (P = 0.05) mothers, and their cohabitation time was shorter (P < 0.05; mean 35 month/median 24 month, SD ±35.8). Incidence of OC significantly increased after hormonal treatment (P = 0.022) and invasive prenatal diagnostics (P < 0.05) compared to GS. GS mothers took folic acid prophylaxis less often than OC (P = 0.02). Smoking, illicit drugs, and external risks like herbicides showed no influence, but GS mothers drink significantly more often alcohol (P = 0.05). We confirmed an increased risk for GS if several factors such as young maternal age, short cohabitation time, and usage of antibiotics coincide with alcohol consumption and associated immune diseases. OC increased after hormonal treatment and invasive prenatal diagnostics.
Zebrafish offer advantages over traditional rodent models in developmental toxicology studies, including low maintenance costs, high fecundity, genetic diversity, and reduced animal welfare concerns (1,2).
Odontoblasts are specialized cells that produce dentin and exhibit unique morphological characteristics; i.e., they extend cytoplasmic processes into dentinal tubules. While osteoblasts, which are typical hard‐tissue‐forming cells, are generated from mesenchymal stem cells during normal and pathological bone metabolism, the induction of odontoblasts only occurs once during tooth development, and odontoblasts survive throughout the lives of healthy teeth. During the differentiation of odontoblasts, signaling molecules from the inner enamel epithelium are considered necessary for the differentiation of odontoblast precursors, i.e., peripheral dental papilla cells. If odontoblasts are destroyed by severe external stimuli, such as deep caries, the differentiation of dental pulp stem cells into odontoblast‐like cells is induced. Various bioactive molecules, such as non‐collagenous proteins, might be involved in this process, although the precise mechanisms responsible for odontoblast differentiation have not been fully elucidated. Recently, our knowledge about the other functional activities of odontoblasts (apart from dentin formation) has increased. For example, it has been suggested that odontoblasts might act as nociceptive receptors, and surveillance cells that detect the invasion of exogenous pathogens. The regeneration of the dentin‐pulp complex has recently gained much attention as a promising future treatment modality that could increase the longevity of pulpless teeth. Finally, congenital dentin anomalies, which are concerned with the disturbance of odontoblast functions, are summarized.
The vital role of folic acid is to reduce the risk of having a neonate afflicted with neural tube defects. The prevalence of neural tube defects (myelomeningocele and anencephaly) has been reported in an incomplete form over the last 40 years in Japan. We aimed to evaluate the total number of neural tube defects including those delivered or terminated, to clarify the proportion of those terminated, and to internationally compare their prevalence. Through information on >311,000 deliveries obtained from 259 hospitals/clinics for 2 years of 2014 and 2015, we identified that the rate of total neural tube defects (termination of pregnancy, live births and stillbirths) was 8.38 per 10,000 deliveries for the year 2014 and was 8.74 for 2015, which were 1.5 and 1.6 times higher than the respective values (live births and stillbirths) reported. It is also observed that the ratio of the total number of myelomeningocele (termination of pregnancy, live births and stillbirths) to that of anencephaly was approximately 1:1.2, that a half of pregnancies afflicted with neural tube defects were terminated, and that the proportion of termination of pregnancy due to myelomeningocele and due to anencephaly was 20 % and 80 %, respectively. Internationally, the real prevalence of neural tube defects in Japan was comparatively high, ranking 5 among the 7 developed countries. In conclusion, the real prevalence of total neural tube defects was approximately 1.5 times higher than that currently reported by the Japan Association of Obstetricians and Gynecologists. This article is protected by copyright. All rights reserved.
The TATA-binding protein-associated factor 1 gene (TAF1) encodes the largest component of the TFIID complex. O'Rawe et al. (2015) reported 12 boys with X-linked syndromic mental retardation-33 (MRXS33). They exhibited growth delay, global developmental delay, intellectual disability (ID), generalized hypotonia, and joint hypermobility. This article is protected by copyright. All rights reserved.
Hypertrophic cardiomyopathy (HCM) is a significant clinical problem associated with sudden death. HCM is very rare in fetuses with a poor outcome. Only isolated cases have been reported, for example, in fetuses of genetic disorders (Uemura et al. 2016). This article is protected by copyright. All rights reserved.
Environmental enrichment (EE) after birth has been reported as an intervention improving the anxiety-like behavior and cognitive deficit due to maternal restraint, foot-shock, or social stress during pregnancy. However, it remains unclear whether EE after birth could benefit the early prenatal undernourished offspring. In this study, we examined the effect of daily handling as a simple EE intervention on the aberrant behavior of prenatally undernourished rats. The male rat offspring exhibited anxiety-like behavior at 9 weeks of age due to maternal food restriction in early pregnancy. Our study shows that the daily handling after weaning has an anxiolytic effect in the prenatally undernourished offspring without affecting the behavior of prenatally well-nourished offspring. Conversely, the concentrations of dopamine, serotonin, norepinephrine, and their metabolites were not altered in the prefrontal cortex by prenatal undernutrition or daily handling after weaning. We investigated whether the anxiolytic effect of daily handling was mediated by the protein kinase C (PKC) pathway using the PKC inhibitor, chelerythrine. The anxiolytic effect of the handling was not canceled by chelerythrine injection in prenatally undernourished offspring, whereas chelerythrine induced an anxiety-like behavior in control rats. Our results suggest that maternal undernutrition in early pregnancy induces an anxiety-like behavior accompanied with a PKC pathway-hyporesponsiveness; however, daily handling ameliorates the anxiety-like behavior through a PKC-independent pathway.
Thanatophoric dysplasia and achondroplasia are allelic disorders caused by a constitutively active mutation in the FGFR3 gene. Because thanatophoric dysplasia is a lethal disorder and achondroplasia is non‐lethal, they need to be distinguished after ultrasound identification of fetal growth retardation with short limbs. Accordingly, we have developed a noninvasive prenatal test using cell‐free fetal DNA in the maternal circulation to distinguish thanatophoric dysplasia and achondroplasia. A multiplex PCR system encompassing five mutation hotspots in the FGFR3 gene allowed us to efficiently identify the responsible mutation in cell‐free DNA in all examined pregnancies with a suspected thanatophoric dysplasia or achondroplasia fetus. This system will be helpful in the differential diagnosis of thanatophoric dysplasia and achondroplasia in early gestation and in couples concerned about the recurrence of thanatophoric dysplasia due to germinal mosaicism.
in a previous article we reported that mutations favoring cancer at adulthood seemed to improve fertility and limit miscarriages. Because spontaneous abortion may result from anomalies in embryo, we questioned if an increased frequency of congenital malformation could be evidenced among cancer prone families. oncogenetics database (≈193,000 members) of the comprehensive cancer center Jean Perrin was crossed with regional registry of congenital malformations (≈10,000). Among children born between 1986 and 2011, 176 children with malformation matched in both databases. in breast/ovaries cancer prone families, the risk for malformations was multiplied by 2.4 [1.2-4.5] in case of a BRCA1 mutation. Frequencies of malformation in BRCA2 and MMR mutated families were similar to families without a cancer syndrome. In comparison to malformations concerning a unique anatomical system, multimalformations were significantly more frequent in case of BRCA or MMR mutations: compared to families without cancer syndrome, the risk of multimalformations was multiplied by 4.1 [0.8-21.7] for cancer prone families but with no known deleterious mutation, by 6.9 [1.2-38.6] in families with a known mutation but an unknown parental mutational status and by 10.4 [2.3-46.0] when one parent carried the familial mutation. No association with the type of anatomical system was found, nor with multiple births. these results suggest that BRCA and MMR genes play an important role in human embryogenesis and that if their function is lowered because of heterozygote mutations, congenital malformations are either more likely (BRCA1 mutations) and/or more susceptible to concern several anatomical systems. This article is protected by copyright. All rights reserved.
RASopathies including Noonan syndrome (NS), Costello syndrome, and Cardiofaciocutaneous syndrome are caused by heterozygous germline mutations in genes of the RAS/MAPK pathway that plays a role in cellular proliferation, differentiation, and survival. Novel genes associated with RASopathies are increasing in number (Aoki et al. 2016). This article is protected by copyright. All rights reserved.