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M J Leboutet

Publications and source records attributed to M J Leboutet.

At least 55 records · Page 3Linked to original sources
PubMed1984

[Morphological effects of microinjections of Lewis rat serum into nerves of Lewis rats].

Recent reports have shown that intraneural injections of sera from patients with Guillain-Barré syndrome have demyelinating effects on rat peripheral nerve. Some authors have proposed that this could merely result from immune phenomena due to species differences. In this study we injected normal human sera and sera from normal Lewis rats into nerves of Lewis rats. We consider that the small lesions observed were due more to the injection procedure itself than to effects of the sera.

Animals↗
PubMed1984

[Asteroid hyalopathy. Ultrastructural study of 3 cases].

The vitreous of three patients with asteroïd hyalosis (average age: 57 years) was obtained by a two-hand closed pars plana vitrectomy. Asteroïd hyalosis was associated with alcoholic neuropathy in the first case, long standing retinal detachment in the second case, and diabetes mellitus in the third case. The visual acuity before and after the surgical procedure improved from 1.2/6 to 6/6 in the first case, from light perception to 0.3/6 in the second case, from 0.6/6 to 4.8/6 in the third case. The vitreous was studied by different ultrastructural technics : transmission electron microscopy (T.E.M.) scanning electron microscopy (S.E.M.) and electron diffraction X ray analysis (E.D.A.X.). By S.E.M. the asteroïd bodies appeared as rounded structures with an irregular surface connected to each other by fibrous strands among sodium chloride crystals. No cellular remnants were observed. By T.E.M. the asteroïd bodies were composed of interwinned ribbons of multilaminar membranes with a periodicity (10 to 60 A) characteristic of complex lipids, especially phospholipids. At the edge of the ribbons there were dots and sometimes clumps of opaque material that tended to crack out of the specimen with the heat of the electron beam. T.E.M. study disclosed the irregular disposition of the calcific bodies. By E.D.A.X. the calcific composition of the rounded structures could be determined : calcium and phosphorus were the main elements detectable in asteroïd bodies of all sizes for all three patients. The average calcium counts for the three successive cases were : 18, 30, 43 and for phosphorus : 9, 14, 26. Potassium was found in the first case, and sulfur in the third case.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1983

Nonviral intranuclear inclusions in a nerve biopsy: an ultrastructural study.

During the ultrastructural study of a nerve biopsy from a diabetic patient suffering from chronic polyradiculoneuritis, we observed that a significant number of endoneural fibroblasts had abnormal nuclei. They contained a round, centrally located inclusion consisting of numerous irregularly arranged filaments approximately 15 nm in diameter. No such lesion in peripheral nerve has previously been reported. Interpretation of these abnormalities is difficult.

Aged↗
PubMed1983

Familial Creutzfeldt-Jakob disease with extensive degeneration of white matter. Ultrastructure of peripheral nerve.

A case of Creutzfeldt-Jakob disease (CJD) in a 52-year-old man is described. At post mortem, extensive involvement of white matter was seen. A few similar cases have been reported mainly by Japanese authors. Our patients belonged to a French family in which 14 cases of CJD over three generations have been recorded. One of the patient's first cousins also had extensive white matter involvement. This is an unusual panencephalopathic form of CJD. The causes of the involvement of white matter are unknown. There was no clinical evidence of neuropathy but an electron-microscopic study of biopsied superficial peroneal nerve showed it to be present. Study of peripheral nerves is suggested for all patients with CJD.

Biopsy↗
PubMed1983

[Melanocytoma of the iris and ciliary body and multiple pigmented tumors ultrastructural study].

The authors report an ultrastructural study of a melanocytoma of the iris and the ciliary body which has been excised by an iridocyclectomy because of the extension into the angle and of the rapid growth. In this tumor we have found a great number of melanocytes, some melanophages and few collagen fibers. The melanocytes include a lot of mature melanosomes. The melanophages are characterized by the compound melanosomes and the lysosomial bodies. In both cells the number of melanosomes was high, filling nearly all the cytoplasm. The evolution for the eye after the operation was good but the patient died two years later for an unknown reason. This iris tumor was associated with two others pigmented tumors: a benign cystic nevus of the caroncula and a choroidal nevus. The ultrastructural study of the conjunctival nevus shows vacuolated cells under the basement membrane. These cells are organised around large surface of mucus. These epithelial inclusion cells look like pseudocyst formation. The originality of this work is that few melanocytoma of the iris has been studied by transmission electron microscopy and the association with two others benign nevi (caroncula, choroïd).

Aged↗
PubMed1983

[Embryologic study of the lacrimal ducts in man. Apropos of 10 cases].

The embryology of the human lacrimal system is not clearly defined in the literature and two hypotheses exist: the first suggests that the origin of the lacrimal system is from an ectodermal fold forming a sulcus of the naso-optic fissure. The second, with few defenders, describes the first rod of cells as meeting a second one which appears to emerge from the primitive nasal cavity. A study of ten human embryos, aged from 14 to 25 weeks and with a length of 12 to 33 cm, examined by histologic sections of 10 microns, revealed no lacrimal origin in the primitive nasal cavity near the inferior meatus. A further interesting point was that in three of the four embryos aged four months the lacrimal point was opened. Most authors, however, found the lacrimal sac and the nasolacrimal duct to be dilated, especially in one case where the inferior part of the nasolacrimal duct at the ostium below the inferior turbinate and meatus was widely dilated. In all the cases, the lower end of the duct was separated from the nasal cavity by a fine membrane in opposition with the nasal mucosa.

Epithelium↗
PubMed1982

Peripheral nerve damage during multiple myeloma and Waldenstrom's macroglobulinemia: an ultrastructural and immunopathologic study.

Peripheral nerve biopsies of 22 patients who were seen with a peripheral neuropathy were studied. On each occasion an ultrastructural study was performed and on 12 occasions an immunopathologic study was done. Ten patients had Waldenström's macroglobulinemia and 12 had multiple myeloma. Cellular infiltrates were observed in three cases of Waldenström's macroglobulinemia by light microscopy. A widening of the myelin sheath, corresponding to an accumulation of macroglobulin, was found in three cases of Waldenström's macroglobulinemia. The presence of abundant deposits of amyloid was noted in one case of multiple myeloma. These diverse features show the various possible mechanisms that can produce peripheral nerve damage during the course of malignant dysglobulinemias. The segmental demyelination is probably of immunologic origin. The axonal lesions cannot be explained satisfactorily except in those rare cases where amyloid deposits are present in the endoneurium.

Adult↗
PubMed1982

Coexistence of minicores, cores, and rods in the same muscle biopsy. A new example of mixed congenital myopathy.

The authors report on the ultrastructural study of a muscle biopsy carried out in a child 6 years after the first biopsy which had led to diagnosis of "multicore disease". Clinical evolution following a few years of muscular involvement had been favorable. The lesions observed in the second biopsy were again characterized by the presence of multicores, but in addition to cores and rods. All of these abnormalities could sometimes be noted in a single muscle fiber. Although rare cases of an association of two types of lesions have been reported, no study has hitherto shown multicores, cores, and rods in the same biopsy. This observation might confirm the possibility of common pathogenic mechanisms producing these lesions.

Biopsy↗
PubMed1981

Cryoglobulinemic neuropathy: ultrastructural study of the nerve capillaries.

The authors report here the case of a female patient who developed symmetrical polyneuropathy of the lower limbs a few months after she was found to have a myeloma with cryoglobulinemia. In musculocutaneous nerve biopsy material from this patient, electron microscopy showed pathological changes in the nervous tissue together with axonal degeneration and demyelination. But the most striking finding was the presence in the endoneurial space, of numerous masses made up of closely packed tubular structures. These masses occurred also in the walls and even in the lumen of all the vasa nervorum. Their morphologic features and dimensions were identical to cryoprecipitate which the authors extracted from the serum and which they examined with electron microscope.

Basement Membrane↗