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A Smadja

Publications and source records attributed to A Smadja.

At least 37 records · Page 2Linked to original sources
PubMed1989

[Histologic study of the gonads in ovarian differentiation during organogenesis].

We report the results of a histologic study of the differentiating ovary carried out in human embryos and fetuses. Up to the sixth week, the anlage of the gonad is formed by the proliferation of cells originating from the coelomic mesothelium; this proliferation starts with the migration of the primordial germ cells. Between the sixth and the tenth weeks, the primary mesenchyma invades the epithelial mass and divides it into "cords"; by division, the germ cells contained within the mass become ovocytes. At the tenth week, the gonad takes shape and is separated from the mesonephros. At the twelfth week, the gonad is formed of two zones; an outer zone formed of epithelial clusters arranged in rosettes around the ovocytes; and an inner, mesenchymal, zone that becomes the medulla and separates the outer epithelial zone from the remnants of the mesonephros. At the sixteenth week, the gonad becomes the ovary that contains millions of primordial follicles; each follicle consists of an ovocyte surrounded by a ring of granulosa cells originating from the coelomic epithelium; the follicles are separated from each other by mesenchymal cells that form the cortical stroma. The remnants of the mesonephros are clearly separated from the ovary by the medulla.(ABSTRACT TRUNCATED AT 250 WORDS)

Embryonic and Fetal Development↗
PubMed1989

[New findings on the embryogenesis of the vagina].

The authors have studied a series of twelve embryos between 4 and 8 weeks of age and 21 fetuses between 9 and 25 weeks of gestation. From this material they have made a study of the embryogenesis of the vagina, which shows that the whole of the vagina, and not only the lower third or fifth, is derived from the vaginal plate, this latter is the result of proliferation and fusion of the two sino-vaginal bulbs. This study supports the unitary theory ascribing formation of the vagina to ascension and extension of the vaginal plate which is derived from the cloacal sinus.

Embryonic and Fetal Development↗
PubMed1988

[Comparative morphological study of the peritoneal mesothelium and the germinal epithelium of the ovary. Histogenetic evidence for endometriosis].

The purpose of this study was to evaluate comparatively the morphology of germinal epithelium and of peritoneal mesothelial cells in women with and without endometriotic foci. In women without enometriotic foci, transmission electron microscopy revealed that plasma membranes of both cell types can form villous process, and that tonofilaments can be found in the cytoplasm; the microfibrils are well defined and may be arranged in perinuclear location or closely packed on the surface. Desmosomes are occasionally found in both cell types. In endometriotic foci, located either in the peritoneum or in the ovary, invaginations of the mesothelium into the underlying stroma are frequently observed, contiguous to well defined endometriotic tubules, or glandlike crypts. These structures are lined by a layer of cuboidal or high columnar cells. The cell membranes are well defined and run parallel to one another; small widening of the intercellular spaces is occasionally associated with a desmosome in the apical portion of the cell. These features may reflect Mullerian induction.

Adult↗
PubMed1987

[Pseudotumoral amyloidosis of the orbit].

A case of orbital amyloid pseudotumour is reported; this rare condition typically present as a ptosis followed by slowly growing orbital neoplasm, in middle-aged women. CT-scan disclose an extra-conal, extra-osseous, calcified mass; preoperative diagnosis of this rare condition might help in avoiding recurrence, probably due to incomplete excision. Pathophysiology of these amyloid deposits remain unknown.

Amyloidosis↗
PubMed1987

[Endometriosis of the uterine cervix. A hypothesis on its histogenesis].

Three cases of endometriosis of the cervix in association with the results of previous studies on the embryogenesis of the uterus made it possible during a morphological study for the authors to hypothesise that cervical endometriosis could develop in mullerian rests which persist in the stroma of the cervix. Menstrual blood incites the development, but degenerate menstrual fragments of endometrium do not implant to cause this development.

Adult↗
PubMed1987

[Tissue changes caused by the diathermy loop].

An attempt of classification of the effects induced by electro-resection on the squamous epithelium of the cervix is presented. It has been founded on predominant features observed on histologic material notably: acantholysis, cells segregation by lysis of intercellular bridges and dislodgment of basal cells from basement membrane by dissolution of reticulin fibers.

Adult↗
PubMed1986

[An integrated histogenetic concept of internal and external endometriosis].

The authors have studied the embryology of the uterus and have studied the comparative morphology of the internal foci of endometriosis, as well as the endometrium itself during the menstrual cycle. These studies have led them to think that the foci of endometriosis, whether they are internal or external, come from cells of coelomic mesothelium that persists in the transitional zone between the myometrium and the endometrium of the uterus, or in the mesothelium that covers the ovary, the tube and the pelvis under the stimulus of substances that are present in degenerate endometrial tissues during menstruation. This unitary idea of histogenesis makes it possible to consider under one heading, if not to unite, all endometriosis occurring anywhere according to their histogenic presentation under the same conditions of the tissues that surround them. It also makes it possible to explain the morphological similarity of endometriosis with the endometrium, although the biological behaviour of the two tissues is different. There is therefore a relationship between endometrium and endometriosis but not a filial one.

Endometriosis↗
PubMed1986

[Gliomas of the uterus. Apropos of 3 cases and review of the literature].

We report three cases of uterine gliomas in young women with a past history of pregnancies and abortions. A survey of the literature revealed that the published cases also concerned young women with the identical gynecological history. The general belief is that the cause of uterine gliomas is the transplanting of fetal nervous tissue during local manipulations in early abortions. Increased numbers of abortions should lead to a higher frequency of such tumors. Transplanted embryonic glial tissue is viable at the beginning of pregnancy and provokes only a weak immunologic rejection. These tumors are benign and no case of transformation into glioblastomas has been reported.

Abortion, Induced↗
PubMed1985

[Structure and function of the fetal umbilical vessels].

A morphological study carried out using electron microscopy has shown that there is an endothelium in the umbilical blood vessels consisting of intercellular spaces which interdigitate with one another and that are not specialization in junction complex. The endothelial cells are rich in their typical organ structure and have pinocytotic vesicles. There media contains a muscular coat which is thicker in the artery than in the veins. The smooth muscle cells also show pinocytotic vesicles. This morphological state leads the authors to two groups of thought: There is active diffusion by a process of "plasma perfusion" from the lumen of the vessels through the vascular wall which forms a physiological system for taking up fluids which in turn is capable of providing for the energy and plastic requirements of the umbilical vessels: The umbilical arteries, because of their thick muscular tunic and because of the ability of the lumen to dilate as there is an absence of an internal elastic membrane, can function not only as tubes for conducting blood but also as organs that regulate the blood flow. On the other hand the umbilical vein, which cannot stretch and cannot retract because its wall is so thin, behaves as an organ to return the blood flow, particularly because it does have an inner limiting layer preventing over-stretching.

Diffusion↗
PubMed1985

[The morphogenesis of vaginal diaphragms. New data].

The authors have studied seventeen fetuses which were stillborn as a result of late abortion or premature labour due to cervical incompetence. The authors examined the theory that suggests that the vagina is developed from the urogenital sinus and Mullerian duct. That theory holds that it is failure of canalization of the junction of the sinus and the duct that causes transverse septum formation in the vagina. According to the authors of this paper this theory does not explain how septum are formed at different places in the vagina and how it is transverse septa are not formed in the uterus. This study allows them to suggest that the vagina itself is formed by a plaque which is entirely originally from the sinus, and that it is because of a failure of this plaque to break down completely leaving behind vestigial shreds to cause these septa to appear in the vagina.

Epithelial Cells↗
PubMed1984

Morphological study of the chorio-allantoic fetal membranes.

Morphological study of the chorio-allantoic fetal membranes has demonstrated the existence of foot processes extending from the main body of amniotic cells and containing microfibrils arranged in dense bundles as described in podocytes of renal glomerulae; on the surface fronds and between their bases many small pits and caveolae are seen; in the cytoplasm of amniotic cells large vacuoles are present; they frequently distort the nuclei into crescentic shapes. In the chorion underlying the amnios, fibroblasts and Hofbauer cells are found; their surface often has overlapping filopidal projections. The syncytium bounding the intervillous space shows a marked resemblance to that of the villi. These morphological features seem to indicate that chorio-allantoic fetal membranes might be an important route for the transporting of fluid from the maternal blood in the intervillous space into the amniotic compartment.

Allantois↗
PubMed1984

[Reflections on endometrial osteogenesis. Apropos of 3 cases].

The authors report three cases of endometrial ossification. They believe that the presence of bone in the uterus is associated with two very distinct situations. One is the retention in utero of fragments of foetal bone after a late abortion. In this case, the bone fragments have a recognisable morphology and a well differentiated structure. The other situation is osseous metaplasia of elements which they believe to be of Mullerian origin, arising in the myo-endometrial transitional zone.

Abortion, Induced↗
PubMed1984

[New data on the morphology of the allanto-chorion fetal membranes].

The authors have carried out an electron microscopic study on the morphology of the allanto-chorial membranes of late pregnancy. The demonstration of these amniotic cells with their long pedicles which resemble those of renal podocytes, together with the presence of intercellular canals lined by long villi which themselves cross over with one another to make a grid, and the existence of intracellular canals that make transcytoplasmic tunnels, permit the authors to suggest that they are dealing with a morphological illustration of ultrafiltration processes. The authors suggest that the forces that bring about plasma filtration from the intervillous chamber towards the amniotic compartment crossing the allanto-chorial membranes are the same as those that cause glomerular filtration. These are hydrostatic pressure in the intervillous chamber and the oncotic pressure within the amniotic compartment.

Allantois↗