PubMed Health⌕ Search

Biomedical subjects

M Deprez

Publications and source records attributed to M Deprez.

16 recordsLinked to original sources
PubMed2000

Clinical and neuropathological parameters affecting the diagnostic yield of nerve biopsy.

The value of nerve biopsy in the investigation of peripheral neuropathies is an important and controversial issue, partially obscured by the large variations in the diagnostic yield routinely reported for this procedure. The aim of this study was to evaluate the clinical and neuropathological parameters affecting the yield of nerve biopsy. We compared the experience of two independent neuropathology laboratories with different patient recruitment and neuropathological methods over 11 years (01/1987-12/1997). Clinicopathological correlations were studied retrospectively in 355 patients. Using the same criteria of evaluation, contributive biopsies accounted for 35.5% in one laboratory, and 47.3% in the other. Clinical parameters affecting the yield of nerve biopsy were: (a) the presumptive diagnosis at time of referral for biopsy; (b) the distribution of symptoms; and (c) the interval between disease onset and biopsy. Greater yield was associated with clinically suspected vasculitis, inflammatory demyelinating neuropathy or hereditary sensorimotor neuropathies. Contributive findings were more often reported with multifocal or asymmetrical presentations, and onset-to-biopsy interval of less than 6 months. The contribution of nerve biopsy varied according to neuropathological techniques: (a) serial sections on frozen. paraffin-embedded and resin-embedded material improved sensitivity for interstitial pathology: (b) combined muscle biopsy increased sensitivity in the detection of vasculitis; and (c) teasing of nerve fibers added critical information to other classical techniques in only 4/102 cases.

Adolescent↗
PubMed1999

A new combined bodian-luxol technique for staining unmyelinated axons in semithin, resin-embedded peripheral nerves: a comparison with electron microscopy.

Quantitation of unmyelinated fibers (UF) in peripheral nerves has classically relied upon ultrastructural morphometry. Because this method is time-consuming, it is not typically performed in routine analysis of nerve biopsies. We applied the Bodian-Luxol technique to detect unmyelinated axons by light microscopy on semithin sections from resin-embedded nerve tissue. Estimates were compared to ultrastructural counts. The staining appeared highly specific for axons. Excellent correlation was found between optic densities and the population of UF larger than 0.5 microm. The smallest profiles detected by light microscopy had a diameter close to 0.6 microm. This new technique is not a substitute for ultrastructural quantitative morphometry of UF, as very small unmyelinated axons, especially regenerating ones, can not be reliably visualized. However, it provides a valuable light microscopic method for evaluating axonal loss among UF.

Axons↗
PubMed1999

Infantile and juvenile presentations of Alexander's disease: a report of two cases.

We describe 2 new cases of Alexander's disease, the first to be reported in Belgium. The first patient, a 4-year-old girl, presented with progressive megalencephaly, mental retardation, spastic tetraparesis, ataxia and epilepsy: post-mortem examination showed widespread myelin loss with Rosenthal fibers (RFs) accumulation throughout the neuraxis. She was the third of heterozygotic twins, the 2 others having developed normally and being alive at age 5 years. The second patient developed at age 10 years and over a decade spastic paraparesis, palatal myoclonus, nystagmus, thoracic hyperkyphosis and thoraco-lumbar scoliosis with radiological findings of bilateral anterior leukoencephalopathy. Brain stereotactic biopsy at age 16 years demonstrated numerous RFs. With these 2 cases, we review the literature on the various clinico-pathological conditions reported as Alexander's disease. We discuss the nosology of this entity and the pathogeny of RFs formation and dysmyelination. Clues to the diagnosis of this encephalopathy in the living patient are briefly described.

Adolescent↗
PubMed1998

Preoperative evaluation of 54 gliomas by PET with fluorine-18-fluorodeoxyglucose and/or carbon-11-methionine.

UNLABELLED: This study evaluates the usefulness of PET for the preoperative evaluation of brain gliomas and methods of quantification of PET results. METHODS: Fifty-four patients with brain gliomas were studied by PET with 18F-fluorodeoxyglucose (FDG) (n = 45) and/or 11C-methionine (MET) (n = 41) before any treatment. Results of visual analysis, calculation of glucose consumption and five tumor-to-normal brain ratios for both tracers were correlated with two histologic grading systems and with follow-up. RESULTS: Visual analysis (for FDG) and tumor-to-mean cortical uptake (T/MCU) ratio proved to be the best tools for the evaluation of PET results. Methionine was proven to be better than FDG at delineating low-grade gliomas. Tumor-to-mean cortical uptake ratios for FDG and MET were clearly correlated (r = 0.78), leading to the equation T/MCU(FDG) = 0.4 x T/MCU(MET). We showed a good correlation between FDG PET and histologic grading. MET uptake could not differentiate between low-grade and anaplastic astrocytomas but was significantly increased in glioblastomas. Low-grade oligodendrogliomas exhibited high uptake of FDG and MET, probably depending more on oligodendroglial cellular differentiation than on proliferative potential. Uptake was decreased in anaplastic oligodendrogliomas, probably due to dedifferentiation. Care must be taken with peculiar histologic subgroups, i.e., juvenile pilocytic astrocytomas and oligodendrogliomas, because of a discrepancy between high PET metabolism and low proliferative potential (good prognosis). Both tracers proved useful for the prediction of survival prognosis. Methionine proved slightly superior to FDG for predicting the histologic grade and prognosis of gliomas, despite the impossibility of differentiation between Grades II and III astrocytomas with MET. This superiority of MET could be explained by patient sampling (low number of Grade III gliomas submitted to examination with both tracers). The combination of both tracers improved the overall results compared to each tracer alone. CONCLUSION: Both tracers are useful for the prediction of the histologic grade and prognosis. The apparent superiority of MET over FDG could be due to the small number of Grade III gliomas studied with both tracers.

Brain↗
PubMed1997

Tricho-hepato-enteric syndrome: further delineation of a distinct syndrome with neonatal hemochromatosis phenotype, intractable diarrhea, and hair anomalies.

We report on two sibs with syndromal congenital iron storage disease. Prenatal symptoms were IUGR, hydramnios, and placental hyperplasia. Clinical anomalies included hypertelorism and sparse, thin, curly hair (trichomalacia). Clinical course was marked by intractable diarrhoea, with normal histological and enzymological studies, cholestatic jaundice, hepatomegaly appearing after 30 days, and progressive liver failure, leading to death after a few months. The only metabolic anomaly was progressive hypermethioninemia. Pathologic examination of both children showed a similar pattern of multivisceral iron deposit compatible with a diagnosis of neonatal hemochromatosis: extensive liver fibrosis or cirrhosis with nodular regeneration, cholestasis, ductular proliferation, and hepatic, pituitary, thyroidal, adrenal, and pancreatic iron deposition. The unusual course for neonatal hemochromatosis in both sibs combined with concordant extrahepatic anomalies suggest that they could have a specific iron storage syndrome with possible autosomal recessive inheritance, probably similar to the sibship reported by Stanckler et al. [Arch Dis Child, 57:212-216, 1982].

Amino Acid Metabolism, Inborn Errors↗
PubMed1997

Idiopathic hypertrophic cranial pachymeningitis mimicking multiple meningiomas: case report and review of the literature.

A case of idiopathic hypertrophic cranial pachymeningitis with an unusual and misleading manifestation is reported. Computed tomography scan, angiographic and magnetic resonance imaging findings were suggestive of multiple meningeal neoplasms and a correct diagnosis was made only after meningeal biopsy. This 44-year-old patient had a previous history of an ill-defined systemic disorder associating episcleritis, erythroderma nodosa and multiple peripheral arthritis. We review previous reports of idiopathic cranial pachymeningitis with emphasis on radiological investigation techniques, histopathology and possible dysimmune mechanisms of pathogenesis.

Adult↗
PubMed1996

Expression of the 67-kD laminin receptor, galectin-1, and galectin-3 in advanced human uterine adenocarcinoma.

Alterations of tumor cell interactions with laminin, a basement membrane glycoprotein, are consistent features of the invasive and metastatic phenotype. Qualitative and quantitative changes in the expression of cell surface laminin-binding proteins have been correlated with the ability of cancer cells to cross basement membranes during the metastatic cascade. Such phenotypic modifications are usually associated with poor prognosis. In this study, the authors examined the possibility that expression of three laminin-binding proteins, the 67-kD laminin receptor (67LR), galectin-1, and galectin-3, is altered in human endometrial cancer in a fashion similar to that reported in other carcinomas, such as breast, colon, and ovarian cancer. Twenty advanced uterine adenocarcinomas were analyzed for expression of these three molecules using immunoperoxidase staining and specific antibodies. The authors found a significant increase in the expression of the 67LR and galectin-1 in cancer cells compared with normal adjacent endometrium (P = .0004 and .0022, respectively). As observed in other carcinomas, a significant down-regulation of galectin-3 expression was found in endometrial cancer cells compared with normal mucosa (P = .02). In the galectin-3 positive tumors, galectin-3 was detected in the cytoplasm and/or nucleus of cancer cells. Interestingly, tumors in which galectin-3 was detected only in the cytoplasm were characterized by deeper invasion of the myometrium than lesions where galectin-3 was found both in nucleus and cytoplasm (P = .02). This study shows an alteration of nonintegrin laminin-binding protein expression in advanced human endometrial cancer. Further studies on larger populations should determine the prognostic value of the detection of these laminin-binding proteins in endometrial carcinoma. Inverse modulation of the 67LR and galectin-3 appears to be a phenotypical feature of invasive carcinoma.

Adenocarcinoma↗
PubMed1996

Decrease in systemic tolerance to fed ovalbumin in indomethacin-treated mice.

The oral administration of non-steroidal anti-inflammatory drugs (NSAID) to animals induces a quick increase in intestinal permeability and secondary inflammatory lesions of the intestine. The mechanisms leading to the inflammatory lesions are hypothetical. The increased intestinal permeability could allow a greater mucosal and systemic penetration of fed antigens and bacterial products leading to an abnormal mucosal and systemic immune and inflammatory response toward these materials. We examined the effect of oral dosing with indomethacin on ovalbumin serum levels and the systemic immune response to ovalbumin in mice fed with ovalbumin. The ovalbumin serum level was higher in indomethacin-treated mice and the increase was proportional to the dose of indomethacin. It was associated with epithelial and subepithelial lesions. Moreover, the systemic humoral and, to a lesser extent, the cellular tolerance were partially abrogated in the treated mice. These findings suggest that the oral administration of indomethacin in mice induces an increased passage of fed antigen through the intestinal epithelium associated with a decrease in systemic tolerance to this antigen. The reason for this decrease remains unclear. Besides a disequilibrium between systemic and mucosal immune responses, a loss of integrity of the intestinal epithelial cells and a direct immunomodulating effect of indomethacin may also be involved. This decrease in systemic tolerance to luminal antigen could be involved in the development of NSAID enteropathy.

Administration, Oral↗
PubMed1995

Morphological changes of thymus in retrovirus-induced murine acquired immunodeficiency syndrome (MAIDS).

The possible contribution of the thymus in the setting of acquired immunodeficiencies is still questioned. Here we report some new findings regarding a potential involvement of the thymus in mice infected with RadLV-Rs, a viral mixture inducing murine acquired immunodeficiency syndrome (MAIDS). Thymi were sequentially removed, weighted and morphologically analyzed at different time intervals post-infection. Infection with RadLV-Rs led to a decrease in thymus weight mostly apparent from the fourth week. The first changes were seen at the third week as perivascular clusters of B-cells at the cortico-medullary junction. The ensuing process of atrophy mainly involved the cortex, while a mixed population of large T- and B-cells filled the medulla. These observations are discussed with regard to the pathological changes occurring in other lymphoid and non-lymphoid organs, in the context of the lymphoproliferation and immunodeficiency characterizing the disease, and by comparison with other models of retrovirus-induced immunodeficiencies.

Animals↗
PubMed1994

Population dynamics of CD4+ T cells lacking Thy-1 in murine retrovirus-induced immunodeficiency syndrome (MAIDS).

Increased numbers of CD4+ Thy-1- cells have been described in the spleen (SP) of mice with retrovirus-induced immunodeficiency (MAIDS). Since this phenotypic abnormality might have considerable functional importance, the expansion of the CD4+ Thy-1- subset in MAIDS was characterized further. CD4+ Thy-1- and Thy-1+ T-cells from infected mice expressed similar densities of CD3 and TCR alpha/beta. In contrast, the Thy-1- subset was uniformly CD44hi, even early in the disease when part of Thy-1+ cells were still CD44lo. The emergence of CD4+ Thy-1- cells occurred first in SP and lymph nodes and was observed later in thymus. The important fraction of CD4+ cells lacking Thy-1 normally present in Peyer's patches was only weakly modified. Despite the major expansion of the CD4+ Thy-1- phenotype, the proliferating fraction was not higher in this subset than in CD4+ Thy-1+ cells from infected mice. Persistence after hydroxyurea administration was identical in both subsets, indicating similar mean cell lifespans. Taken together, these results show that the major expansion of CD4+ Thy-1- T-cells in MAIDS is not ascribable solely to increased proliferation within this subset. Phenotypic analysis suggests that CD4+ Thy-1- cells result from the differentiation of Thy-1+ cells induced by activation signals related to retroviral infection.

Animals↗
PubMed1994

Thymus involvement in murine acquired immunodeficiency (MAIDS).

Due to self-renewal of the peripheral pool of T-cells, adult thymectomy has normally little influence on immunocompetence. However, thymus might play a more important role in the setting of viral-induced cytopathic effects on T-cells in the periphery. Therefore, thymus weight, cell numbers, and subset distribution were sequentially analysed after infection with RadLV-Rs, a viral mixture known to induce murine retrovirus induced immunodeficiency (MAIDS). Infection induced thymic atrophy (concerning organ weight as well as total cell number) which culminated seven weeks after inoculation. The atrophic process mostly reflected the depletion of double positive CD4+ CD8+ cells since their proportion sharply decreased around week 6. Single positive T-cells were less affected by the process. The proportion of B-cells progressively increased. Surprisingly, there was a strong correlation between the extent of atrophy and the frequency of B-cells in the thymus. Finally, an abnormal CD4+ T-cell subset lacking Thy-1 and previously described in the periphery also appeared in the thymus and its frequency was strongly correlated with the expansion of B-cells in this organ.

Animals↗
PubMed1994

[Rupture of a superficial femoral aneurysm in the context of neurofibromatosis. Report of a case].

The authors observed the spontaneous rupture of a dysplastic superficial femoral artery in a 47 years old patient with Von Recklinghausen disease. The patient presents a gigantism of his right lower limb. On angiography, the femoropopliteal axis is polyaneurysmal and there is evidence of rupture at mid-thigh. The diseased artery is excluded by interposition of a dacron prosthesis, with reimplantation of the deep femoral artery. Histology shows fibrohyalin thickening of the intima. Dysplasia of large limb arteries is excessively rare in Von Recklinghausen disease.

Aneurysm, Ruptured↗
PubMedDate not supplied

The veno-occlusive disease of the liver.

BACKGROUND AND OBJECTIVE: The veno-occlusive disease of the liver (VOD) is a disorder caused by the non-thrombotic occlusion of the central veins of hepatic lobules. The clinical features are similar to those of intrahepatic portal hypertension (unexplained weight gain, ascites, painful hepatomegaly, jaundice). In the past, this disease was rather infrequent and was linked to the absorption of toxic agents, liver irradiation or chemotherapy. However, the intensification of treatment protocols before hematopoietic stem cell transplants has considerably increased its incidence. The strategies used for its prevention and treatment remain limited in efficacy. The present review was undertaken in order to assess progress in the diagnosis and management of this severe complication in stem cell transplantation. INFORMATION SOURCES: The method used for preparing this review was an examination of 250 relevant articles or abstracts published in journals covered by Medline. STATE OF ART: Despite the progress made toward the understanding of its physiopathology and the identification of its risk factors, VOD is still one of the leading causes of morbidity and mortality during the first two months post-BMT, and therefore often constitutes a limitation for the further increment of the dose of antineoplastic drugs. This may be explained by the difficulty in making an early diagnosis of this problem, at a time when therapeutic intervention may be more effective, and, on the other hand, the lack of a well-established prevention and treatment approach for patients with VOD. PERSPECTIVES AND CONCLUSIONS: New diagnostic procedures, such as laparoscopic liver biopsy, and new therapeutic approaches, such as transjugular intrahepatic portosystemic shunting (TIPS) or defibrotide, are now being evaluated. However, additional studies will be needed to determine the most appropriate therapy for each VOD patient depending on the severity of the disease.

Bone Marrow Transplantation↗