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PubMed1988

IFN-gamma-regulated expression of a differentiation antigen of human cells.

Mouse mAb M111 identifies a cell surface glycoprotein of 115,000 to 135,000 Da. M111 was expressed constitutively in subsets of cells of multiple lineages at discrete stages of cell maturation, suggesting that M111 is a differentiation Ag of the three germ layers. Ag expression could be induced by IFN-gamma but not by IFN-alpha, IFN-beta, or TNF. Induction of M111 expression was maximal at 48 h of culture in 200 U/ml of IFN-gamma and was independent of induction of class II MHC Ag. Induction was dependent on the cell type used. Nine colon cancer cell lines of undifferentiated phenotype were constitutively M111-; IFN-gamma induced M111 expression in seven of them. In contrast, IFN-gamma failed to induce M111 expression in six of six M111- ovarian cancer cell lines. Eight normal fibroblast cultures tested were M111-; they could not be induced to express M111. Three of five sarcoma cell lines were M111+; culture in IFN-gamma induced an increase in M111 expression in all of them. Constitutive and IFN-gamma-induced expression of M111 was independent of constitutive and induced expression of HLA class I and II molecules. IFN-gamma-mediated induction of M111 expression was not accompanied by coordinate changes in the expression of other differentiation traits. These results suggest that expression of the M111 gene is controlled by two mechanisms, one related to differentiation and the other activated by IFN-gamma.

Animals↗
PubMed1988

[Pathogenetic synopsis of diverticular disease of the female urethra].

Diverticular disease of the female urethra is rare, but not so rare as assumed hitherto. The predominant theory is that diverticula urethrae is secondary to infection of the glandulae paraurethrales, but they can be easily pared out, and this together with their three-dimensional appearance with subdivision in side, undermines this theory. On the other hand, the known fact that urethral diverticula can be observed in female babies and girls of school age and also in urethral moulds of healthy young women, in which widened urethral glands can be found, supports the idea of a congenital origin. The irritability of the female urethra results from the fact that it is made up of two germ layers. Inflammation of paraurethral ducts causes secondary widening of small congenital diverticula of the female urethra. Proximally located diverticula can irritate sphincter function, as does invasive treatment. In some cases endoscopic therapy might be justified rather than plastic surgical removal via the vagina. The history, symptoms, diagnostis, histology and secondary pathology are indicated only very briefly.

Diverticulum↗
PubMed1986

Teratocarcinoma derived from mouse zygotes after the introduction of activated human c-Ha-ras DNA.

We attempted to produce transgenic mice harboring the normal or activated human c-Ha-ras gene in order to examine the function of activated oncogenes in tumorigenesis. During the process of development, it happened that not only normal looking fetuses were obtained but also malformants, developmentally arrested conceptuses and tumors. Six such abnormally developed embryos were found to have been integrated with the activated human c-Ha-ras gene. One of the two tumors thus obtained was formed after the injection of 6.3 kb DNA fragment containing the gene for p21 with valine at the twelfth position. This tumor was integrated with two copies of the introduced DNA at a particular site in a chromosome and arranged in tandem in a head to tail direction. Histological analysis revealed that this tumor was constructed from at least three types of cells: two originating from different germ layers (one endoderm and the other mesoderm) and the third from an extra-embryonic ectoderm. The other tumor revealed similar features. Thus, it was strongly suggested that these tumors were derived from the very early developmental stage of the embryo, and had features very similar to those of teratocarcinoma.

Animals↗
PubMed1987

The embryonic origin of connective tissue mast cells.

To find out whether mast cells are derived from the neural crest or from mesoderm, explants of avian blastoderm, from which the neural crest was excluded, were grown on the chorio-allantoic membrane of chick hosts. The grafts were fixed in aldehyde fixatives and stained to demonstrate metachromatic connective tissue mast cells. In grafts of chick endoderm and mesoderm, mast cells were present despite the absence of neural crest derivatives. To ascertain whether these mast cells were perhaps of host origin, in a second experiment quail embryos were used as donors; explants included all three germ layers and were delimited so as to exclude neural crest cells. The proportion of the mast cells present that showed very large nucleoli such as are characteristic of quail cells was far in excess of that observed in mast cells of a young chick and much closer to that seen in these cells in a young quail. The same was true for grafts in which quail mesoderm had been combined with chick endoderm. Taken together, the results show that connective tissue mast cells are mesodermal rather than neural crest in origin.

Animals↗
PubMed1987

[Teratoma of the testicle with very highly differentiated structures].

A teratoma is described that was composed of differentiated derivatives of the germ layers--ectoderm (central and peripheral nervous systems, epiphysis, adenohypophysis, and skin with appendages), endoderm (bronchial and intestinal epithelia), and mesenchyme (fibrous and smooth-muscle tissue, cartilage, and bone) and of mesoderm (mesonephros).

Adolescent↗
PubMed1986

Scanning electron microscopic observations on developing opossum embryos: days 9 through 12.

During the first 9 d of development in Didelphis, the 3 germ layers are established and the initial formation of their derivatives occurs. During this time the embryos float within uterine secretions, each separated from the uterine mucosa by a shell membrane. Organogenesis begins during the last 3 1/2 d of the 12 1/2 d gestation period and corresponds to the time when the yolk sac placenta is associated with the uterine epithelium. During this period development proceeds at an explosive rate, culminating in a fetus-like creature capable of surviving in the pouch. Early in d 10, the forelimbs are present as limb buds. Late in the 10th d the embryo descends into and becomes enveloped by its own yolk sac. Mandibular and hyoid arches, and prominent digital ridges on the forefeet are characteristic external features. By d 11, the hindlimb is represented by a bud the eyes and external auditory meatus are established and an open mouth with protruding tongue is characteristic of this stage. Digits are present on the forefeet but lack claws. During the 12th d the oral shield develops, curved claws are prominent features of the forefeet and digital ridges are seen on the hindfeet. Prior to birth the periderm covers the eyes, ear pinnae and sides of the mouth.

Animals↗
PubMed1986

Observations on cell lineage of internal organs of Drosophila.

Adult Drosophila mosaics can be used to study cell lineage and to map relative positions of primordia at the blastoderm stage. This information can define which germ layer an organ comes from and can help build models of genetic regulation of development. Here we use the sdh cell marker to map internal organs in mosaics made by nuclear transplantation. We confirm that oenocytes arise from the same progenitors as the adult epidermis, but that muscles and fat body have a separate (mesodermal) origin and that the precursors of epidermis and central neurones are closely intermingled in the ventral, but not dorsal, epidermis. We find that the malpighian tubules are more closely related to the hindgut than the midgut and are therefore ectodermal in origin. We find that each intersegmental muscle in the thorax arises from one specific parasegment in the embryo, but that very small numbers of myoblasts wander and contribute to muscles of inappropriate segments. We present evidence indicating that the visceral muscles of the midgut have a widely dispersed origin (over much of the embryo) while the somatic mesoderm of the female gonad comes from a small number of abdominal segments. The visceral mesoderm of the hindgut develops from a localized posterior region of the embryo.

Abdomen↗
PubMed1985

The system specifying body position in the early development of Xenopus, and its response to early perturbations.

Evidence is presented that the system setting up preliminary specifications for contributions to the axial body plan, across vegetal regions of the Xenopus embryo, acts in a widespread way at early stages. Mechanisms that regulate the spatial profile of this primary positional variable, and thus ensure the constancy and harmony of the body plans normally achieved, have lost this integrative ability by the 4-cell stage one hour after the plasm shifts that precede first cleavage and symmetrize the egg. Abnormal, partial or distorted profiles of the positional system across whole eggs or isolates, recorded by these times, are retained to give correspondingly partial or imbalanced mes/endodermal pattern at tailbud larval stages. There is evidence that subsequent 'back-up' positional interactions, which can heal gross positional discontinuities in isolated presumptive lateral half-eggs and so restore bilateral symmetry, also do this at the price of loss of complete pattern specification. This is probably because of an asymmetrical principle whereby relatively activated (dorsoanterior specified) material can raise the level of originally posterior material on contact, whereas the reverse interaction cannot occur. The observations are discussed in relation to apparently different behaviour in certain other amphibian embryos, and to our knowledge of other positional interactions, normal and also experimentally provoked, such as those that set up the germ layers.

Animals↗
PubMedDate not supplied

[A rare cervico-facial teratoma in a newborn female infant].

The Authors report a case of a rare and very voluminous teratoma with uncommon location (the right cervico-facial region) and extracranial seat in a female newborn. The teratoma was excised in the 18th day of life. It showed cystic and solid lesions. The tissues were derived from the three germ layers and were prevalently mature; only a bit of them was represented by embryonic mesenchymal tissue. The baby, followed and checked up during all the first year of her life, showed a normal evolution and absence of recurrences.

Female↗
PubMed1985

Regional specificity of glycoconjugates in Xenopus and axolotl embryos.

This paper reviews work on the presence, synthesis and developmental regulation of glycoconjugates (proteoglycans, glycoproteins and glycolipids) in the early amphibian embryo. In the axolotl there is little regional specificity of protein synthesis until the tailbud stage, but substantial regional specificity of glycoprotein synthesis from the end of gastrulation. Glycolipid synthesis is more uniform although a number of unique species are made in the epidermis. Isolated explants from axolotl early gastrulae show three types of behaviour in terms of glycoprotein synthesis, corresponding to the classical germ layers. Xenopus embryos at this stage show a higher degree of mosaicism. Changes of glycoprotein synthesis in response to mesodermal or neural induction follow the predicted course depending on the regional character of the induced tissue. The regional binding patterns of a number of lectins and monoclonal antibodies specific for particular carbohydrate determinants are presented and their significance discussed.

Ambystoma↗
PubMed1985

An unusual thyroid tumor: a comparison to a literature review of thyroid teratomas.

Presented is a patient with a tumor containing elements from two germ layers. It was associated within the patient's thyroid gland (located in a benign adenoma), but since the elements were widely separated from each other the tumor could not be classified as a teratoma or hamartoma. To our knowledge no similar tumor has been described. The interesting characteristics of this patient are described. The characteristics of this benign tumor are compared with those of cases in the literature of adult thyroid teratomas.

Adult↗
PubMed1985

Highlights of craniofacial morphogenesis in mammalian embryos, as revealed by scanning electron microscopy.

The craniofacial region has a complex developmental history. Some of the major morphogenetic events of this region are described for the mouse embryo, as revealed by the use of scanning electron microscopy. The three germ layers, the primitive building blocks of the embryo, are delineated during gastrulation. During neurulation, the outer ectodermal layer gives rise to the nervous system. Several other events occur concomitantly with neurulation. These include regional subdivision of the mesoderm, body folding, turning, and formation of the heart and gut. The craniofacial region, as well as a number of other regions or organ systems, undergoes major developmental events during the phase of embryogenesis called organogenesis. The visceral (branchial) apparatus develops around the primitive oral cavity and pharyngeal region of the foregut, and gives rise to many of the structures of the head and neck. The face develops from the first visceral arches and derivatives of the frontonasal prominence. The tongue also originates from tissue prominences derived from the visceral arches. The oral and nasal cavities are initially continuous broadly with one another. As a result of partitioning, paired nasal cavities develop and become largely separated from the underlying oral cavity. Scanning electron microscopy reveals much about the morphological events occurring during formation of the craniofacial region. However, emphasis in future studies should be placed on determining the underlying cellular and molecular mechanisms causing these events.

Animals↗
PubMed1979

Effect of the T-mutation on histogenesis of the mouse embryo under the testis capsule.

Mouse embryos homozygous for the T-mutation show abnormalities, severer at the posterior embryonic regions, by day 9 of gestation and die before day 11 in utero. To analyse development potentially of the T/T embryos fragments of their anterior and posterior portions were grafted into the testes of adult T/+ mice, and examined histologically for the tissues formed after 1 month. The grafted tissues of the T/T embryos grew beyond the destined lethal stage and gave rise to benign teratomas composed of mature tissues. Although there were some different features of the tissues formed in the teratomas derived from different portions and stages of the embryos, their types were essentially identical between wild-type and the mutant teratomas. Statistical analysis showed that frequency of the cartilage and/or bone formation was significantly lower in the posterior mutant teratomas. It cannot be concluded, however, that this difference is essentially caused by T-mutation. The main conclusion of present experiments is that grafted portions of T/T embryos have the potentiality to develop into teratomas containing derivatives of all three germ layers.

Animals↗
PubMed1979

Fate maps and cell differentiation in the amphibian embryo--an experimental study.

The aim of this paper is to test two different fate maps for the amphibian blastula with respect to their predictions concerning the process of cell differentiation. The first of these fate maps is the one proposed by Vogt, according to which all three germ layers can be projected on to the surface of the embryo. The second is a revision which claims that only endoderm and ectoderm are located in the surface, while the mesoderm is represented by free cells in the interior of the embryo. The testing has been performed by observing the differentiation of small explants of cells taken from various regions of the embryo. It was found that the spontaneous cell differentiation comprises three patterns: undifferentiated cells (free interior cells and circumpolar endodermal cells), fibroblast-like cells (the remaining endodermal cells) and epidermis (ectodermal cells). Further differentiation occurs only through induction, exerted either by the fibroblast-like endodermal cells or by heparan sulphate. When induced, the equatorial ectodermal cells give rise to swollen, hyaline cells (chordocytes), while the remaining ectodermal cells form a sequence of cell differentiation patterns, mesenchyme cells, nerve cells, melanophores and xanthophores. The free interior cells differentiate into striated muscle cells and elongated collagen-producing fibroblasts. Our results thus confirm the revised fate map, and they also give an insight into the mechanisms of the initial cell differentiations in the amphibian embryo.

Ambystoma↗
PubMed1979

Cystic fibrosis in adults: an autopsy study.

An annotated catalog of clinical and pathologic observations in an adult population with CF has been presented. The spectrum of disease is broad, and the diagnosis usually requires the demonstration of abnormalities in multiple systems. Tissues of each germ layer have been found involved in CF. Correlation of clinical and pathologic observations suggests that manifestations are essentially episodic and focal. In this population, the most characteristic abnormalities recognized by the pathologist are focal biliary cirrhosis, distinctive obstructive lesions of the male genital tract, prolonged staphylococcal or pseudomonas colonization of respiratory secretions, and obstructive bronchopulmonary disease. Some form of pancreatic atrophy is usually present.

Adult↗
PubMed1982

Experimental fetal infection with bovine viral diarrhea virus. II. Morphological reactions and distribution of viral antigen.

The effect of an infection with bovine viral diarrhea virus on fetal bovine tissues as well as the tissue-localization of viral antigen are described. Four bovine fetuses, 120-165 days of gestation, were inoculated in utero with a second passage virus strain. Lymphoid tissues were studied by light and electron microscopy. The infection induced precocious development of the secondary lymphoid organs. Characteristic changes were seen in postcapillary venules, cells of the mononuclear phagocyte system and lymphoid follicles. In all four fetuses the thymus was hypoplastic. In three fetuses this implicated a morphological immaturity, but no actual pathological alterations. In the fourth fetus, the hypoplasia was caused by necrosis and depletion of lymphocytes, attended by infiltration of macrophages. Histopathological changes were also noted in the cerebellum of three fetuses, consisting of necrosis in and depletion of the external germ layer and in the skin and mucous membranes of all four fetuses. The viral antigen was present in cells of the mononuclear phagocyte system, primarily in the lymphoid tissues. The infection was further demonstrated in the affected cerebelli.

Animals↗
PubMed1983

[Experimental induction of teratoma in rats].

To induce an experimental teratoma, fetuses of Wistar strain rats were removed from the uterus, and the visceral yolk sac was left hanging through the fetectomy incision. After several weeks of this treatment, a tumor developed in these animals with or without both side oophorectomy. Despite the fact that the visceral yolk sac is composed of endoderm and mesoderm, the tissues in the resulting tumor obtained from the ectopically implanted yolk sac showed derivatives from all three germ layers, including skin, bone, gut and nervous tissues. Changes in hormonal environment induced by oophorectomy did not affect the process of experimental tumor induction. When 7,12-dimethylbenz-(a)-anthracene (DMBA) was directly applied to the yolk sac at the fetectomy, a neoplasm mainly consisted of yolk sac elements was investigated after two to four months of the treatment. From the results of this experiment, it was seemed that an embryonic and extraembryonic teratomatous tumor might have been derived from the visceral yolk sac.

9,10-Dimethyl-1,2-benzanthracene↗