29 research outputs found
The Role of gp130 in cerebral cortical development: in vivo functional analysis in a mouse exo utero system.
Extralysosomal localization of acid paranitrophenylphosphatase activity in the developing rat cerebellar cortex.
The Role of gp130 in cerebral cortical development: in vivo functional analysis in a mouse exo utero system.
The role of gp130 in cerebral cortical histogenesis remains unknown. Mice lacking gp130 showed a hypoplastic cortical plate and decreased incorporation of 5-bromo-2'-deoxyuridine (BrdU) in progenitor cells of the developing cerebrum. In contrast, injection of leukemia inhibitory factor (LIF), a gp130 ligand, into the lateral cerebral ventricle of wild-type embryos exo utero induced hyperplasia of the cerebral cortex and increased the incorporation of BrdU in progenitor cells. Furthermore, chronologically controlled injection of LIF followed or preceded by BrdU revealed that gp130-mediated signals promote the progenitor cells to reenter the stem cell cycle without affecting the duration of cell cycle and enhance the migration of postmitotic neurons in the developing cerebrum
Morphometric study on the characteristic external features of normal and abnormal human embryos
The embryonic period is characterized by organogenesis and accompanying dynamic changes in external features. The measurement of human embryos has been limited to whole body dimensions, such as crown-rump length. More detailed measurements would add quantitative information about these characteristic events and provide a better understanding of normal and abnormal embryonic development. In the present study, we defined axes, landmarks, and measurements for human embryos, and measured 250 externally normal human embryos at Carnegie stages 14-23 (6.5-29.3 mm in crown-rump length, approximately 5-8 weeks of estimated ovulation age) that were fixed in Bouin's solution and preserved in 10% formalin solution. The axes, landmarks, and measurements defined for human embryos are corresponding to those in human and primate fetuses. The whole body, head, face, and extremities were measured using a scale attached to a dissecting microscope. Axial length, head height plus ear-shoulder length plus trunk height, was designated as a new measurement of the whole body, which is comparable with crown-rump length. Approximate standards of these measurements were obtained. The ratios of some measurements to trunk height and between the different parts were also obtained, and several different developmental patterns were recognized. The reproducibility of each measurement was evaluated by measuring 50 specimens three times each at intervals of one or two months. As a pilot study for the application of the proposed measurements, 84 human embryos with external anomalies, including holoprosencephaly, anomalies of extremities, and pharyngeal arch anomalies, were measured using the same method, and a few tendencies characteristic to holoprosencephaly were noticed
Arthroscopic Excision of Intra-Articular Osteoid Osteoma at the Elbow
Osteoid osteoma (OO) apparent in the intra-articular region of the elbow is very rare. Although computed tomography-guided excision and radiofrequency ablation have been recognized as useful treatment options, arthroscopic excision has recently received focus as an alternative strategy for lesions close to neurovascular structures or intra- and juxta-articular lesions. We herein report a 17-year-old female who underwent arthroscopic treatment for intra-articular OO located at the olecranon/coronoid fossa. Her symptoms included elbow pain that was exacerbated at night and contracture of elbow flexion-extension, and she was diagnosed with intra-articular OO after 12 months of symptomatic history. Arthroscopically, thorough synovectomy for both the anterior and posterior aspects of the joint enabled definition of the tumor margin with hyperemic alteration and excision of the lesion as an en bloc specimen. At the 12-month follow-up, the patient had no recurrence of elbow limitation or pain. This case report describes the advantages of arthroscopic treatment, including a low-invasive approach and easy accessibility to the whole intra-articular space, which can provide clear visualization of the tumorous lesion
The suppression of maternal-fetal leukemia inhibitory factor signal relay pathway by maternal immune activation impairs brain development in mice.
Recent studies in rodents suggest that maternal immune activation (MIA) by viral infection is associated with schizophrenia and autism in offspring. Although maternal IL-6 is though t to be a possible mediator relating MIA induced these neuropsychiatric disorders, the mechanism remains to be elucidated. Previously, we reported that the maternal leukemia inhibitory factor (LIF)-placental ACTH-fetal LIF signaling relay pathway (maternal-fetal LIF signal relay) promotes neurogenesis of fetal cerebrum in rats. Here we report that the maternal-fetal LIF signal relay in mice is suppressed by injection of polyriboinosinic-polyribocytidylic acid into dams, which induces MIA at 12.5 days post-coitum. Maternal IL-6 levels and gene expression of placental suppressor of cytokine signaling 3 (Socs3) increased according to the severity of MIA and gene expression of placental Socs3 correlated with maternal IL-6 levels. Furthermore, we show that MIA causes reduction of LIF level in the fetal cerebrospinal fluid, resulting in the decreased neurogenesis in the cerebrum. These findings suggest that maternal IL-6 interferes the maternal-fetal LIF signal relay by inducing SOCS3 in the placenta and leads to decreased neurogenesis
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Spatio‐temporally regulated expression of receptor tyrosine kinases, mRor1, mRor2, during mouse development: implications in development and function of the nervous system
Backgrounds
Drosophila neurospecific receptor tyrosine kinases (RTKs), Dror and Dnrk, as well as Ror1 and Ror2 RTKs, isolated from human neuroblastoma, have been identified as a structurally related novel family of RTKs (Ror‐family RTKs). Thus far, little is known about the expression and function of mammalian Ror‐family RTKs.
Results
We have identified murine Ror‐family RTKs, mRor1 and mRor2. Both mRor1 and mRor2 genes are induced upon neuronal differentiation of P19EC cells. During neuronal differentiation in vitro, the expression of mRor2 is transiently induced, although that of mRor1 increases continuously. During embryogenesis, the mRor1 gene is expressed in the developing nervous system within restricted regions and in the developing lens epithelium. The expression of mRor1 is sustained in the nervous system and is also detected in non‐neuronal tissues after birth. In contrast, the expression of mRor2 is detected mainly in the developing nervous system within broader regions and declines after birth. Possible relationships of mRor1 and mRor2 genes with previously identified mutants have also been examined.
Conclusions
The developmental expressions of mRor1 and mRor2, in particular in the nervous system, are differentially regulated, reflecting their expression patterns in vitro. mRor1 and mRor2 may thus play differential roles during the development of the nervous system