Search PubMed⌕ Search

Biomedical subjects

C Deminiere

Publications and source records attributed to C Deminiere.

At least 19 recordsLinked to original sources

MR imaging of intrarenal macrophage infiltration in an experimental model of nephrotic syndrome.

The objective of this study was to use MR imaging to detect macrophage infiltration of the kidney after injection of ultrasmall superparamagnetic iron oxide (USPIO) particles in a rat model of experimental nephropathy. Ninety micromol of USPIO were injected intravenously in 10 rats with nephropathy secondary to intravenous injection of 5 mg of puromycin aminonucleoside (PAN), and in 10 control rats. The signal intensity was measured in each kidney compartment before and 24 h after injection of the contrast agent. FLASH sequences were performed on a spectrometer operating at 4.7 T. MR findings were compared with histological data. Twenty-four hours after injection of USPIO, a significant decrease (P < 0.0001) was observed in signal intensity in each kidney compartment in the PAN group. There was no variation in the control group. In the diseased kidneys, histological data revealed the presence of macrophages with iron oxide particles within their cytoplasm and lysosomes. Using USPIO, MR imaging can evidence infiltration of the rat kidney by macrophages.

Animals↗

Xenogeneic ossicular implants: an experimental study of heterotopic, demineralized, lyophilized, porcine implants in the guinea-pig.

This study was done to compare the outcome of porcine ossicular implants in the middle ear and the subcutaneous dorsal region of the guinea-pig to those of allo-implants implanted in parallel in the dorsal region. The implants were heteropic, xenogeneic, demineralized (HCl), lyophilized and sterilized. The evaluation was histological (light microscopy and scanning electron microscopy) and immunological (immunofluorescence staining). Fifty-four guinea-pigs were implanted in the middle ear and 14 of them were also implanted subcutaneously in the dorsal region with xeno-implants and allo-implants. The middle ear implants were found to be constantly reossified and coated with normal mucosa with only a minimal immune reaction. In contrast, the dorsal xeno-implants were found to be the target of mononucleic infiltration, fibrous encapsulation and an influx of immunoglobulins resulting in segregation. The corresponding allo-implants were found to be partially reoccupied and reossified. These findings highlight the value of HCl demineralization in the induction of non-species-specific Bone Morphogenetic Protein and the failure of attempts at immuno-despecification. It appears that the fate of the implant depends less on its antigenic load than on the site of implantation. In this regard the middle ear is apparently very advantageous. The very good short-term tolerance and recovery observed in the middle ear xeno-implant suggest that these implants offer sufficiently good results to warrant clinical testing.

Animals↗

Renal angiomyolipoma: a clinicopathologic, immunohistochemical, and follow-up study of 46 cases.

We reviewed 46 cases of renal angiomyolipoma covering the period from 1977 to 1997. Eight cases were associated with tuberous sclerosis and one with lymphangiomyomatosis. Histologically, the lesions were most often classic with the three usual components, i.e., mature adipose tissue, thick-walled blood vessels, and smooth muscle. Seven cases were particularly misleading: three cases were entirely adipose mimicking liposarcoma: two cases had an exclusively smooth-muscle component, one mimicking lymphangiomyomatosis and one with epithelioid cells; another case had a monophasic epithelioid pleomorphic component ("REON": renal epithelioid oxyphilic neoplasm) and proved to be fatal; and another case was associated with collecting duct carcinoma. The immunohistochemical profile showed the coexpression of alpha-smooth-muscle actin and HMB45. Our study is the first to show positivity of estrogen and progesteron receptors or both in more than 25% of cases. Of 35 cases with follow-up information, only one patient died of malignant spread of angiomyolipoma.

Actins↗

[Gynecomastia].

Gynaecomastia is the least rare manifestation of the male breast disease. Urologists must therefore be able to distinguish the various forms of gynaecomastia, eliminate a testicular tumour and identify the main causes by performing a simple but complete assessment. Medical treatment is fairly disappointing. Surgical treatment is required in patients presenting with complications or when persistent gynaecomastia is aesthetically bothersome.

Gynecomastia↗

[The value of transrectal MRI in the staging of localized prostate cancer].

OBJECTIVE: To determine the diagnostic value of transrectal magnetic resonance imaging (MRI) in the local staging of prostatic cancer. METHOD: 75 patients suffering from clinically localized prostatic cancer were included consecutively from December 1992 to September 1996. An MRI examination (1.5 Tesla, Siemens) with a transrectal coil was performed before radical prostatectomy. The results of this examination in terms of capsular invasion, seminal vesicle lesion and apical invasion were correlated with the results of histological examination of the operative specimen and the findings of digital rectal examination, transrectal ultrasonography, serum PSA level and biopsy mapping. RESULTS: The best performance of transrectal MRI concerned elimination of seminal vesicle lesion with a specificity of 92%. The positive predictive value of transrectal MRI was 90% for the capsular invasion. The positive predictive value of transrectal MRI was 56% for the apex, the sensitivity was 40% and the specificity was 82%. When transrectal MRI did not reveal any extraprostatic involvement the risk of positive margins on radical prostatectomy was less than 6%. CONCLUSION: In this study, transrectal MRI appeared to be satisfactory to improve the staging of localized prostate cancer, especially in terms of seminal vesicle lesion and apical invasion, but, most importantly, appeared to be very useful to predict negative resection margins.

Aged↗

IgM demyelinative neuropathy with amyloidosis and biclonal gammopathy.

A 59-year-old man developed a sensorimotor neuropathy of the upper and lower limbs, associated with a biclonal gammopathy, within the space of a few months. Each of two paraproteins was coupled with a distinct IgM kappa IgG lambda light chain. Examination of a nerve biopsy specimen by electron microscopy revealed a demyelinative process with a widening of the interlaminar space in the myelin sheath, as well as deposits of amyloid substance between nerve fibers. Direct immunofluorescence revealed the presence of IgM and of the kappa light chain in certain Schwann cells, while the lambda IgG was fixed to the amyloid deposits. Immunoperoxidase histochemistry showed a positive reaction in normal human nerve tissue to the immune serum IgM and kappa light chain. The findings suggest that the widening of the interlaminar space of the diseased myelin corresponds to an active fixation of immunoglobulin on the sheath of the Schwann cell. The presence of two light chains in this patient's gammopathy caused a dual pathology: the kappa chain, a demyelinative neuropathy, and the lambda chain, a primary amyloidosis, with deposits in the peripheral nerve and in the kidney.

Amyloidosis↗

[Primary non-Hodgkin's malignant lymphomas of the brain. Anatomoclinical and immunopathological study of 21 cases].

Twenty one cases of primary malignant lymphoma of the brain are studied. These tumors very seldom extend from the brain (one case in 21). There were no nodular forms and tumors of high-grade malignancy predominated (Kiel's classification). Immunopathological studies performed in eighteen cases showed immunoglobulin secretions in seven. Unlike other locations of non-Hodgkin lymphoma, prognosis depends on therapy and not on histological type. The outcome was improved by radiotherapy, sometimes combined with chemotherapy. Mean survival time was one month for untreated patients or patients treated only by surgery, and 32 months for patients treated by brain irradiation and chemotherapy.

Adult↗

Amyloid neuropathy and multiple myeloma. Ultrastructural and immunopathological study of two cases.

Report of 2 patients suffering from sensory peripheral neuropathy and multiple myeloma. In 1 case, peripheral neuropathy occurred several months before the appearance of multiple myeloma. A peripheral nerve biopsy exhibited numerous amyloid deposits within the endoneurium. Amyloid deposits have been estimated to occur in 15% of cases of multiple myeloma, but only 4 other detailed observations of amyloid deposits within the endoneurium have been reported in the literature. Other mechanisms might be involved since most peripheral neuropathies associated with multiple myeloma do not exhibit any amyloid deposits.

Amyloidosis↗

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↗

[Familial malignant carotid body chemodectoma with lymph node metastases. Light and electron microscopy study (author's transl)].

A case of malignant carotid body chemodectoma with neighbouring lymph nodes metastases is reported. The case is noteworthy as it was accompanied by another jugulotympanic chemodectoma. There was also hereditary component as four of the patients forebears had been operated for cervical chemodectomas. An ultrastructural study showed the characteristic secretory granules. 32 other cases of tumors of carotid body and jugular glomus with metastases are reviewed.

Adolescent↗

Polyneuropathy in Waldenström's macroglobulinemia. Deposition of M component on myelin sheaths.

A chronic sensory neuropathy was the initial symptom in a case of Waldenström's macroglobulinemia in a 53-year-old woman. Ultrastructural analysis of a biopsied peripheral nerve revealed a modification of the lamellar structure of the myelin sheath. Immunofluorescent microscopy showed IgM-positive deposits on the myelin sheath. The monoclonal globulin (M component) present in the myelin appears to be a causative factor in the neuropathy.

Female↗

Myelin modifications in 8 cases of peripheral neuropathy with Waldenström's macroglobulinemia and anti-MAG activity.

Characteristic myelin modifications in patients with IgM monoclonal gammopathy and anti-MAG activity have mainly been studied in cases of undetermined significance, but also exist in cases with indolent Waldenström's macroglobulinemia, i.e., when lymphoplasmocytic infiltration in bone marrow is 15% or more, without any visceral involvement. Since 1983, the authors have examined nerve biopsies from 8 cases with Waldenström's macroglobulinelia by direct immunofluorescence examination on frozen sections and ultrastructural examination. At direct immunofluorescence, fixation of anti-IgM serum on myelinated fibers was present in 7 cases. At ultrastructural examination, a widening of some myelin lamellae at the periphery of a few fibers was visible in 8 cases. A few fibers with hypermyelination were present in 5 cases. In 2 of these 5 cases widening of some myelin lamellae was present in numerous fibers, 88% in one of them. Frequently, there was a major widening of some myelin lamellae with dilated lamellae present in the inner part of the myelin sheath. Certain lamellae were more dilated, up to 50 nm. Occasionally, enlarged lamellae were not compacted with each other. The authors also examined nerve biopsies from 36 patients with IgM monoclonal gammopathy of undetermined significance and anti-MAG activity, but found only one case with major widening of some myelin lamellae. Five other cases with major widening of some myelin lamellae, 4 Waldenström's macroglobulinemia and 1 IgM monoclonal gammopathy of undetermined significance, have been reported. Given that demyelinating neuropathies are far more numerous in cases with IgM monoclonal gammopathy of undetermined significance, it is likely that cases of indolent Waldenström's macroglobulinemia are prone to develop major myelin modifications, possibly due to another mechanism, added to the classic anti-MAG activity.

Aged↗