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PubMed2006

[The study of separating murine embryonic fibroblast from embryonic stem cells by the differential adhesion method].

This study has established a simple method of separating murine embryonic fibroblasts (MEF) from embryonic stem cells (ES cells). The adhesion rates of MEF and ES cells were compared to find out the opitimum time of removing MEF. The result shows that 1.5h and 0.5% gelatin concentration is the opitimum condition of removing MEF. Furthermore, the ES cells which have been purified have the same plating efficiency and the ability of three germ layers differentiation as the unpurified ES cells. After differential adhension, there is strong ALP activity in ES cells. All the results show that the purified ES cells are still in the state of undifferentiation and maintain the pluripotent.

Animals↗
PubMed2006

[Psychodermatology: a collaboration between psychiatry and dermatology].

Dermatology is of special importance in consultation-liaison practice. The brain and the skin originate from the same germ layer, the ectoderm, in the embryo. In later periods of life, the various ways these two organs influence each other has been the subject of many studies published in this field. These studies are divided into three groups: 1- studies about stress and dermatologic diseases, 2- psychoanalytic and psychodynamic approaches to psychodermatologic diseases, and 3- clinical research and treatment of psychodermatologic diseases. Recently, in some countries which are aware of the importance of the subject, in the psychodermatology section psychiatrists, dermatologists, psychologists and residents work together as a team. In fact, it has been already accepted that there is a need for association between psychiatry and dermatology in many cases. This association between the two disciplines aims to enhance the success of therapy and psychiatric support for patients who primarily have psychiatric disease, but project that as a dermatologic disease, on the one hand. On the other hand, it provides a more holistic, and satisfying approach for both doctors and patients having primarily dermatologic disease, but who develop psychiatric problems secondarily. In this article, psychodermatology investigations and the relationship between the skin and psyche, diseases discussed in this context, and overlapping areas of psychiatry and dermatology are reviewed, and it is aimed to attract attention to this topic.

Dermatology↗
PubMed1991

Morphogenetic features in the tail region of the rat embryo.

The secondary (direct) body formation is a mechanism of development in which morphogenesis of various organs occurs directly from a mass of undifferentiated mesenchymal cells (blastema) without previous formation of germ layers. It is characteristic of the posterior end of the embryonic body, i.e. of the tail bud of tailless and the tail of tailed mammals. Development of the neural tube occurring by this mechanism (secondary neurulation) has been previously explained. We investigated the morphogenetic mechanism by which two other axial structures in the rat tail develop: the tail gut and the notochord. Both structures develop from an axial condensation of undifferentiated mesenchymal cells (tail cord) of tail bud origin. The tail gut forms in a similar way to the secondary neural tube: cells in the ventral part of the tail cord elongate, acquire an apicobasal polarity and form a rosette-like structure around a lumen in the centre. The notochord forms by detachment of a group of cells of the tail cord dorsally to the developing tail gut. The peculiarities of this morphogenetic mechanism in comparison with those in other parts of the embryo are discussed. Causal (including evolutionary) explanations of this mechanism are ruled out.

Animals↗
PubMedDate not supplied

A case of neurenteric cyst.

An eight-month-old female infant with a neurenteric cyst situated in the lumbar region is presented because of its rarity and because it can mimic other neurological malformations which occur on the same site. Microscopic examination of the surgically excised cyst revealed Water-Paccini corpuscles, lymphoid follicles, intestinal mucosa and meningeal tissue which originated from two ectoderm and endoderm-germ layers.

Female↗
PubMed1991

[Cystic teratoma of the neck].

Teratomas of the neck are very rare, and up to now only a small number of cases has been described (10 in adults), while in children it is a more frequent finding (132 described cases). It is judged that up to 4% of all teratomas in children are located in the cervicothyroid region. The paper presents a case of a cystic teratoma of the neck in a male child of 1.5 years of age, which gradually increased in it's size during the course of 12 months prior to operation. The tumor had the dimensions 3.7 x 3.2 x 2.7 cm, it was multicystic, and clinically it gave the impression of a bronchial cyst. Histologically the tumor contained elements of all three primary embryonic germ layers.

Dermoid Cyst↗
PubMed1991

Nasopharyngeal teratoma as a respiratory emergency in the neonate.

We report a congenital nasopharyngeal teratoma which presented as acute neonatal airway obstruction. After immediate orotracheal intubation, a pedunculated mass, which filled the nasopharyngeal and oropharyngeal cavities, was completely removed. Histological examination of the specimen revealed as a mature teratoma, composed of all three germ layers with recognizable early organ differentiation.

Emergencies↗
PubMed1991

[Monoclonal antibodies against intermediate cytoskeletal filaments. Their importance in the study of tissue differentiation and biopsy diagnosis].

The expression of intermediate filaments during tissue differentiation, in mature tissues and in their neoplastic derivatives (lungs, thyroid gland, kidney, uterus, CNS) was investigated by means of monoclonal antibodies prepared in our departments (Institute of Molecular Genetics, Czechoslovak Academy of Sciences, Prague and in the Department of Immunology and Molecular Biology, Brno). The conclusions of these investigations provide evidence of the restricted specificity of detection of intermediate filaments in relation to germ layers and mesenchymal vs. epithelial set-up of tissues and the need of knowledge of the differential programme of a given tissue for the interpretation of the presence of intermediate filaments in tumours which develop from it.

Antibodies, Monoclonal↗
PubMed1990

[Mibelli's porokeratosis gigantea].

This case report deals with the giant form of porokeratosis of Mibelli, porokeratosis Mibelli gigantea. Over the last 40 years, the 55-year-old man concerned had observed a centrifugal expansion of a single hyperkeratotic lesion until it covered the whole of the right hand and forearm. Besides the characteristic histological alterations, we saw capillaries with unusually thickened walls owing to basal lamina multiplication. In the centre of the lesion atrophy of the epidermis and of the corium was visible. These observations indicate an alteration in two germ layers in porokeratosis.

Humans↗
PubMed1990

[Sacrococcygeal teratoma. Prenatal diagnosis and prognosis].

The routine use of ultrasonics during pregnancy allows an early diagnosis of a sacrococcygeal teratoma (SCT) with a high degree of certainty. The perinatal management is shown in a four case example prenatally diagnosed. The assessment of N-Acetylcholinesterase in the amniotic fluid in cases of cystic teratomas does not allow a safe differentiation from a myelomeningocele. A puncture of the tumor can be helpful for the verification of the diagnosis. Cells of all three germ layers may be found in the cytological fluid. The sonomorphological differentiation into solid and cystic tumors may play a significant role for the intrauterine growth. Even when diagnosed very early, cystic tumors do not compromise the intrauterine growth. Large solid tumors may lead to hydrops fetalis and intrauterine death. Furthermore, the prognosis depends on concomitant malformation as well as on the intracorporal spreading of the tumor. Therefore, a careful ultrasonic examination allows a good prenatal prognosis as to the severity of the malformation. Delivery is done by caesarean section in cases of large cystic-solid tumors. Small teratomas as well as most cystic tumors allow vaginal delivery after having been punctured previously.

Adolescent↗
PubMed1990

Effects of relaxation of mechanical tensions upon the early morphogenesis of Xenopus laevis embryos.

In Xenopus laevis embryos at the early gastrula stage, circumferential tensions of embryonic ectoderm were relaxed by making sagittal or transversal slits in the ventral parts of embryos and inserting into surgical cuts the sectors of homologous tissue from same-stage embryos. Changes in tensile patterns were controlled by measuring cell surface angles. Immediate decreases in surface cell wall tension as related to transversal wall tension were registered. Within minutes of the operation, the lobopodial activity of the inner ectodermal surface increased. The subsequent gastrulation movements were disturbed, germ layers partially mixed and archenteron reduced. The areas of extensive cell columnarization in the ectoderm of operated embryos were less regularly arranged and were extended much more ventrally than in intact embryos. Ventro-dorsal migration and latero-medial intercalation of mesodermal cells also were suppressed. As the operated embryos developed, we observed increases in the total amount of neural tissue, associated sometimes with duplication and even triplication of neural tubes, duplication of otic vesicles, partial fusion of axial rudiments, suppression of mesodermal segmentation and branching or bending of notochord. In the gravest cases the antero-posterior embryo polarity was disturbed. In some cases we observed the formation of axial rudiments in ventral implants. The role of tensions in determining the patterns of morphogenetic cell movements and in establishing the morphological order of normal development is discussed.

Age Factors↗
PubMed1985

Normal fates and states of specification of different regions in the axolotl gastrula.

A fate map was constructed for four regions of the early gastrula of Ambystoma mexicanum using orthotopic grafts from donors labelled with FLDx (fluoresceinated-lysinated-dextran). The region around the animal pole gave rise to epidermis only and did not include prospective neural plate. The dorsal marginal zone contributed to cephalic endoderm and to the whole length of the axial mesoderm (notochord and somites), the lateral marginal zone to lateroventral and somitic mesoderm, and the ventral marginal zone to lateroventral mesoderm. It was found that the dorsal marginal zone contributed relatively more to the anterior regions of the mesodermal mantle and the ventral marginal zone more to its posterior parts. The same regions of the gastrula and also vegetal yolky tissue were cultured as explants and labelled with tritiated mannose. Their glycoprotein synthesis pattern was compared to those of the neurula tissues to which they contribute in vivo. Animal pole explants synthesized large amounts of the epidermis-specific marker epimucin. Dorsal marginal zone explants did not synthesize epimucin but did make amounts of S2 and S6 indicative of mesoderm, as well as the notochord-specific markers S2.2 and S3.2. Lateral marginal zone explants showed the same pattern as the dorsal marginal zone including the two notochord-specific markers, although they do not contribute to notochord in vivo. Ventral marginal zone explants were more variable in their behaviour. Yolky tissue from the vegetal hemisphere of the gastrula or the archenteron floor of the neurula synthesized mainly polydisperse material of high molecular weight rather than discrete glycoproteins. The results indicate that at the early gastrula stage states of specification exist which correspond to the three germ layers, ecto-, meso- and endoderm. The ectodermal specification of animal pole explants is quite robust and cannot easily be changed by variation of the culture conditions. However treatment with a concentrated pellet of vegetalizing factor does induce a change to mesodermal specification, which is clearly detectable in the pattern of glycoprotein synthesis. Similar inductive interactions between different regions of the early embryo are thought to occur during normal development.

Ambystoma mexicanum↗
PubMed1987

Peculiarities of the embryonic development of Polypodium hydriforme Ussov (Coelenterata), a parasite of acipenserid oocytes.

"Unicellular" stages (107 specimens) and multicellular stages (64 specimens) of embryogenesis of Polypodium, found in 14 sterlet (Acipenser ruthenus L.) females, have been studied with light microscopy, cytophotometry, and autoradiography following incubation with 3H-uridine. All stages of the embryonic development occur inside host oocytes. The "unicellular" stage includes a binucleate cell with unequally sized nuclei; separation inside it of a small cell around the smaller nucleus, i.e. transformation of the single cell into a complex of 2 cells, the larger one enveloping the smaller; formation of a cavity inside the nucleus of the large (outer) cell, and migration of the small cell into it, and "cell-in-a-cell" stage, the small (generative) cell being inside the cavity formed by the nucleus of the large (trophic) cell. The latter gives rise to a hypertrophied but still unicellular envelope around the embryo, the trophamnion. The multicellular stages start with segmentation of the generative cell into blastomeres. These form a morula lying inside the cavity of the trophamnion. Gastrulation occurs by morular delamination. The inversion of the germ layers, typical of parasitic Polypodium stages, apparently arises during gastrulation. Both the generative cell ("egg") and the blastomeres are haploid, at least until the morula stage. The eggs of Polypodium are the smallest ones among coelenterates; they lack yolk and develop without fertilization. Diploidy seems to be restored during segmentation. The trophamnion cell grows, its nucleus becomes highly polypoid, and its cytoplasm accumulates mucoprotein inclusions. Both the blastomere nuclei and the trophamnion nucleus have large nucleoli and actively synthesize RNA. The stages of embryogenesis of Polypodium closely correspond to stages of the host oogenesis. The embryonic development of Polypodium lasts several years and is the slowest among coelenterates. However, it has some features typical of the class Hydrozoa.

Animals↗
PubMed1988

A mouse pluripotent embryonal stem cell line stage-specifically regulates expression of homeo-box containing DNA sequences during differentiation in vitro.

Mouse embryonal stem (ES) cells have been shown to provide a new model system suitable for the analysis of different aspects of murine development. This report gives evidence that ES cell lines are also most useful for the study of developmentally regulated gene expression in vitro. Homeo-box containing genes which are suggested to play a key role in the regulation of differentiation steps occurring during embryogenesis are stage-specifically transcribed in differentiating murine ES cells: (i) A mouse embryonal stem cell line (ES-12957) was isolated and characterized with respect to its differentiation potential. When injected subcutaneously into syngeneic mice, ES-12957 cells formed fully differentiated teratomas representing derivatives of all three germ layers. When allowed to grow in suspension cultures in vitro, the cells followed a reproducible developmental pathway forming complex organized 'embryoid bodies' which resembled mouse early postimplantation embryos. (ii) A mouse DNA sequence with homeo-box homology (MH-121) was isolated and structurally analyzed. Transcription of a 1.7 kb RNA species from this DNA sequence was demonstrated in ES-12957 cells which were differentiated in vitro. A second, previously described homeo-box gene (Mo-10) was also shown to be expressed in ES-12957 cells in a stage-specific manner. A 4-kb transcript could be identified exclusively in RNA of cells which were allowed to differentiate for 9 days. These findings support the suggestion that the homeo-box genes of mammals, like those of Drosophila, may have important functions during embryonic development.

Animals↗
PubMed1989

Embryonal tumors from transgenic mouse zygotes carrying human activated c-Ha-ras genes.

To investigate the function of activated oncogenes we attempted to create transgenic mice carrying activated human c-Ha-ras genes which have their own promoters. However, we never obtained any transgenic pups which developed to term, because all transgenic embryos were malformed, became developmentally arrested conceptuses or developed embryonic tumors during ontogenesis. The mRNA expression of the transgenes was detected in two tumors obtained after introduction of the DNA fragment containing the activated human c-Ha-ras gene for p21 with valine at the 12th codon or with leucine at the 61st codon. Histological analysis indicated that each tumor consisted of at least three types of cells: two originating from different germ layers (the endoderm in one case and the mesoderm in the other) and the third from extra embryonic ectoderm. It was suggested that the activated human c-Ha-ras gene has a critical effect on the development of tumors in normal embryos as well as in transformation of NIH3T3 cells.

Animals↗
PubMedDate not supplied

Cervical teratoma in Nigeria children.

Cervical teratomas are uncommon tumours. Over an eight-year period, four cases of cervical teratomas were seen in children at the University Teaching Hospital, Ile-Ife, Nigeria. The children ranged in age from two weeks to nine years. In two patients the tumours were noticed at birth but in only one was it symptomatic to be the cause of hospitalization at the age of two weeks. The other two had the tumours for three and six years respectively and presented because of cosmetic embarrassment. All the tumours were easily resected at surgery and two showed an anatomical relationship to the thyroid gland. The post-operative course was uneventful in the four patients. The histopathology of the tumours have shown tissues from the three germ layers with neurological elements predominating in two and thyroid tissue present in the other two. Over a follow-up period varying from one to four years none of the children have demonstrated any abnormality of thyroid functions.

Child↗
PubMed1985

Relationship of the gastrointestinal system to podiatric diagnosis and therapeutics.

Relationships to the gastrointestinal system can be found in the diagnosis and treatment of problems affecting the pedal extremity. This is due to the fact that parts of the gastrointestinal tract are derived from the same germ layer as portions of the foot. An awareness of these relationships can be useful in determining the etiology, establishing a diagnosis, and forming a plan for management.

Adult↗
PubMed1986

Adult intrasellar teratoid tumor.

Intracranial teratomas rarely occur in adults. The most common sites are the pineal followed by the suprasellar or hypothalamic areas. Infrequently, teratomas can arise within the sella turcica and mimic a pituitary adenoma or craniopharyngioma. Teratoid tumors contain tissue arising from only two of the three primitive germ layers, whereas teratomas have elements of all three. The following case illustrates the unusual occurrence of an intrasellar teratoid tumor in a 33-year-old man.

Adult↗
PubMed1988

[Intramedullary mature teratoma associated with an attached cord and an intradural lipoma. Apropos of a surgically treated case. Review of the literature].

The authors report the case of a 33 year-old male with urinary disturbances referred for removal of a spinal intradural mass associated with a L4 spina bifida occulta. At operation three types of lesions were present: a tethered cord, an intradural lipoma of the cauda equina and conus medullaris and an intramedullary mature teratoma. A total removal of teratoma and lipoma and a section of the filum terminale achieved a normalization of urological function. Such mature teratoma that consists of all three germ layers only represent 2% of all intramedullary tumors. Pathogenesis is dysembryoplastic but still remains unclear: germinal cells might have been displaced into the dorsal midline during their normal migration from yolk sac to gonadal ridges. Their association with other dysgenetic lesions such as lipoma or spina bifida is not rare but the links between these different pathologies remain unknown.

Adult↗