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M Praet

Publications and source records attributed to M Praet.

At least 37 records · Page 2Linked to original sources
PubMed1998

Schwannoma of the tip of the nose: MRI.

We report a schwannoma with a rare location at the tip of the nose in a 20-year-old woman with an otherwise unremarkable medical history. The imaging findings underline the usefulness of MRI in narrowing down the differential diagnosis of masses in this region. Once the diagnosis was focussed on a neural origin of the mass, the exact nature of the tumour could not be predicted from the MRI, although the presence of a capsule on imaging studies as well as at operation suggested it was probably a schwannoma. A schwannoma must be considered when one encounters a sharply delineated mass at the tip of the nose, showing high signal on T2-weighted images and strongly contrast enhancement.

Adult↗
PubMed1998

Coexistence of an adrenocortical carcinoma with an abdominal ganglioneuroma in a child.

We report a 3-year, 5-month-old boy with an adrenocortical carcinoma. These tumours are rare and highly malignant in childhood. In most cases they are functional, secreting adrenocortical hormones. In this case there was a misleading coexistence with a second abdominal neoplasm, which was a ganglioneuroma; this is a rare benign tumour arising from the sympathetic nervous system. The imaging investigations and their findings are discussed and correlated with pathology.

Abdominal Neoplasms↗
PubMed1998

Multimodal treatment for hepatocellular carcinoma on cirrhosis: the role of chemoembolization and alcoholization before liver transplantation.

The results of combined trans-arterial chemoembolization (TAE) and percutaneous ethanol injection (PEI) followed by liver transplantation for hepatocellular carcinoma (HCC) are described. Fourteen patients (G2) with tumour stages I-III received a mean of 2 times TAE and 4 times PEI prior to transplantation. Six patients (G1) received no pre-transplant therapy. Tumor size reduced from 37 +/- 16 to 28 +/- 16 mm and alpha-FP from 339 +/- 1057 to 224 +/- 711 ng/mL (p = n.s.). On histopathologic examination (G2 vs. G1) a 100% necrosis of the tumour nodules was seen in 80 vs. 0% (p = 0.001); 60-90% in 3 vs. 1 and 10-50% in 3 vs. 2. Eighty six percent of nodules in G2 and 36% in G1 had a tumour capsule (p = 0.02). After a median follow-up of 26 months (3-60), 2 patients in G1 developed a recurrence of HCC as compared to 0 in G2 (p = 0.0005). The actuarial patient disease-free survival after 48 months was 82% in G2 and 65% in G1. It is concluded that combined treatment with TAE and PEI is inducing necrosis in HCC associated with improved patient disease-free survival following liver transplantation.

Actuarial Analysis↗
PubMed1996

Cellular uptake, cytotoxicity, and transport kinetics of anthracyclines in human sensitive and multidrug-resistant K562 cells.

Multidrug resistance in tumor cells is often associated with the presence of an approximately 170 kDa plasma membrane glycoprotein (Pgp) that acts as a drug-efflux pump and decreases intracellular antitumor drug concentration. We measured the uptake of seven anthracyclines (daunorubicin, doxorubicin, 4'-epi-doxorubicin, 4'-deoxy-doxorubicin, iododoxorubicin, 3'-(3-methoxymorpholino)-doxorubicin (FCE23762) and 4-demethoxy-daunorubicin) into K562 cells sensitive and resistant (K562/DNR) to daunorubicin. The K562/DNR subline expresses Pgp at the membrane surface, whereas its sensitive counterpart does not. Laser flow cytometry was used to quantitate intracellular anthracycline content. Uptake of daunorubicin, doxorubicin, 4'-epi-doxorubicin, and 4'-deoxy-doxorubicin was minimal in the K562/DNR subline as compared to their uptake in sensitive cells. On the contrary, iododoxorubicin, FCE23762, and 4-demethoxy-daunorubicin accumulate to nearly the same extent into sensitive and resistant K562 cells. Growth inhibition data indicated that the resistance factor for iododoxorubicin, FCE23762, and 4-demethoxy-daunorubicin is markedly decreased as compared to the other drugs. Fluorescence measurements were carried out to determine the kinetic parameters associated with the influx and efflux of the drugs into and out of K562 cells. Kinetic data indicated that iododoxorubicin, FCE23762, and 4-demethoxy-daunorubicin are not actively rejected from resistant cells, suggesting that they are poor substrates for Pgp-mediated transport. This observation is related to their ability to overcome the multidrug-resistant phenotype of K562/DNR cells in vitro.

Anthracyclines↗
PubMed1996

Auxiliary liver transplantation: regeneration of the native liver and outcome in 30 patients with fulminant hepatic failure--a multicenter European study.

Auxiliary liver transplantation (LT) is a special procedure of LT which could be proposed to patients with fulminant hepatic failure (FHF) and has for aim that complete regeneration of the native liver (NL) left in place will allow the graft recipient to resume normal liver function after allograft withdrawal. We report 30 cases of auxiliary LT performed for FHF in 12 European centers. Twenty-five of 30 patients were younger than 50 years. The cause of FHF was hepatitis A virus (HAV) in 4 patients, hepatitis B virus (HBV) in 7, paracetamol overdose in 5, ecstasy in 2, hepatotoxic drugs in 4, autoimmune hepatitis in 2, liver lesions of preeclampsia in 1 and unknown in 5. A postoperative, both clinical and histological follow-up of more than 3 weeks was obtained in 22 patients, enabling us to look for indicators predictive of NL regeneration and outcome. Histological changes observed in the NL included complete regeneration in 68%, incomplete regeneration with obvious fibrous sequelae in 14% and severe liver fibrosis or cirrhosis in 18%, of the 22 patients studied. The percentage and distribution of necrosis observed in tissue samples of the NL at the time of transplantation was not related to the final outcome. Complete NL regeneration was observed in 15 patients, out of whom 14 were younger than 40 years. Patients with complete regeneration were mainly affected by FHF due to HAV, HBV, or paracetamol overdose. After a follow-up of 18/11 (mean/median) months (range, 3 to 67 months), 19 of the 30 patients (63%) survived and 13 of them (68%), i.e., 43% of the 30 patients, had resumed normal NL function, with interrupted immunosuppression, the ultimate goal of emergency auxiliary LT. We conclude that, in patients with FHF, auxiliary LT is a procedure feasible in a number of centers and is associated with a complete regeneration capability of the NL in a majority of survivors, especially in those younger than 40 years. Confirmation of these encouraging preliminary results by large-scale prospective studies is required.

Adolescent↗
PubMed1996

Distribution and concentrations of 5-aminosalicylic acid in rectosigmoid biopsy specimens after rectal administration.

PURPOSE: Using the autofluorescent properties of 5-aminosalicylic acid (5-ASA), we studied the penetration and distribution of this molecule in human colonic biopsies at different time intervals after administration of 5-ASA enemas. METHODS: Fluorescence scores of rectosigmoidal biopsy specimens were compared with 5-ASA and acetyl-5-aminosalicylic (Ac-5-ASA) concentrations, determined by high-performance liquid chromatography, in adjacent biopsies and in serum samples. RESULTS: 5-ASA penetrates into the rectal mucosa and into the epithelial cells after local application by means of an enema. We found a characteristic 5-ASA staining of two intramucosal structures that need further identification: intraepithelial triangular configurations and "5-ASA scavengers" in the lamina propria. Fluorescence scores correlate well with 5-ASA concentrations in adjacent biopsies (r = 0.67; P < 0.005) and correlate even better with serum concentrations of 5-ASA (r = 0.84; P < 0.005) and Ac-5-ASA (r = 0.80; P < 0.005), hence reflecting the amount of systemically absorbed and metabolized 5-ASA. CONCLUSION: 5-ASA penetrates into the rectal mucosa after local application. Local availability, assessed by means of fluorescence microscopy, correlates well with serum concentrations.

Administration, Rectal↗
PubMed1996

Polyarteritis nodosa and the antiphospholipid syndrome.

We report a case of biopsy-proven polyarteritis nodosa (classic type in association with the antiphospholipid syndrome. Medium-sized arteriopathy was confirmed on visceral angiography. Elevated anticardiolipin antibodies were detected before initiating therapy with methylprednisolone and IV pulse cyclophosphamide. Rapid subsidence of symptoms correlated with a gradual normalisation of the erythrocyte sedimentation rate. After 6 months of therapy anticardiolipin antibodies were within normal limits. Only one similar case has been reported so far.

Angiography↗
PubMed1996

Novel frameshift mutation in a heterozygous woman with Fabry disease and end-stage renal failure.

UNLABELLED: It is generally accepted that Fabry disease (angiokeratoma corporis diffusum) is an X-linked disorder resulting from the deficient activity of the lysosomal enzyme alpha-galactosidase. In males, the enzymatic defect leads to accumulation of glycosphingolipids, particularly in the kidney which causes end-stage renal disease. We report here a woman who presented in 1987 with focal and segmental glomerulosclerosis and required hemodialysis 4 years later when her son was evaluated for proteinuria. In these patients morphologic, biochemical, and genetic investigations were performed to explore the possibility of a hereditary renal disorder. Ultrastructural examination of the son's renal biopsy specimen revealed lamellated osmiophilic inclusions in the glomeruli, typical of Fabry disease. Four months after kidney transplantation in the mother, a graft biopsy specimen also revealed dense lamellated inclusions on electron microscopy. The leukocyte alpha-galactosidase activity was 0.008 mumol/min.10(9) cells in the son and 0.070 in the mother (range 0.100-0.500 mumol/min.10(9) cells). The diagnosis of Fabry disease was confirmed in both patients by the identification by DNA sequencing of a novel mutation in the alpha-galactosidase gene: one single base pair deletion in exon 3 (7317delA). IN CONCLUSION: (1) end-stage renal disease may occur in heterozygous women with Fabry disease; (2) morphologic lesions due to glycosphingolipid accumulation may be observed in the renal allograft after transplantation, and (3) DNA analysis confirmed the diagnosis by demonstrating a frameshift mutation, which has as yet not been reported.

Adult↗
PubMed1996

Initial experience with the use of preoperative transarterial chemoembolization in the treatment of liver metastasis.

We retrospectively evaluated the influence of preoperative Transarterial Chemoembolization (TAE) on technique and complications, tumour histology, and disease-free survival after surgery for hepatic metastasis. In a 2-year period, a total of 23 patients were treated. In a first group of 14 patients, preoperative TAE was performed; in a second group of 9 patients only surgical resection was done. Extensive tumour necrosis was seen in the majority of patients treated with TAE; in tumours with an important fibrotic component, embolization was less effective. No significant effect was seen on operating time, transfusion requirement or perioperative complication rate. In the group of patients who underwent TAE, survival rate was 93% after a mean follow-up period of 15.5 months (SD: 12.5); recurrence was seen in only 8% of the survivors. In the second group, however, mortality was 33% after a median follow-up of 17.5 months (SD: 10), and recurrence was present in 66.7% of the survivors. These results indicate that preoperative TAE reduces the recurrence rate in the first postoperative year. Thereby survival may be improved in patients with resectable metastatic liver cancer.

Antineoplastic Agents↗
PubMed1995

Contrast media injection in the rat after multiple renal insults. No evidence of additional nephrotoxicity.

Experiments were performed to determine whether water-soluble contrast media (CM) show nephrotoxic properties when injected into rats after multiple renal insults. The latter consisted of combinations of prostaglandin synthesis inhibition (with indomethacin) and/or salt depletion and/or uninephrectomy. Renal function was evaluated by standard clinical methods to measure parameters such as urinary output, urinary osmolality, urinary creatinine excretion and serum creatinine. CM injected after prostaglandin synthesis inhibition alone did not influence urinary creatinine excretion or serum creatinine. After a combination of renal insults a significant increase in median serum creatinine values from 61.88 mumol/l [interquartile range (IR) 17.68] [0.70 mg% (IR 0.20)] to 97.24 mumol/l (IR 79.56) [1.10 mg% (IR 0.90)] was observed but CM or sham injections did not prevent a normalization of serum creatinine. The pattern of recovery of serum creatinine was not influenced by previous kidney mass reduction. It is concluded that the nephrotoxic properties of CM cannot be detected with standard clinical methods in rats after multiple renal insults.

Analysis of Variance↗
PubMed1995

Choroidal biopsy in the diagnosis of a suspect intraocular lesions.

A thirty-eight year-old man, treated medically since 1985 for a chronic pancreatitis, showed a choroidal infiltrate in the superior mid periphery of the left fundus. A thorough systemic examination could not reveal an underlying cause. The differential diagnosis of the lesion included metastasis, intraocular lymphoma and sarcoidosis. Two months later the lesion had increased both on fundoscopy and echography and was accompanied by a serous macular detachment. A choroidal biopsy showed a moderately well differentiated mucinous adenocarcinoma. The primary site could not be determined. The mucinous character is rather suggestive for a gastrointestinal origin. Gastro intestinal choroidal metastases, and more specifically the pancreatic ones, are however rare.

Adenocarcinoma↗
PubMed1995

Eosinophilic myositis resulting from sarcocystosis.

Muscle sarcocystosis is a parasitic infection acquired by ingestion of sporocysts of Sarcocystis species. A case is described where symptoms of fever, chronic myositis and eosinophilia were present. Diagnosis was made via muscle biopsy. Improvement and cure coincided with treatment with cotrimoxazole. A limited review of human muscle sarcocystosis and an outline of the gaps in the knowledge of this infection is presented.

Adult↗
PubMed1994

The development of a decision support system for the pathological diagnosis of human cerebral tumours based on a neural network classifier.

This study describes the use of a topological mapping system in the classification of cerebral tumours and the development of a decision support system based upon that classifier. Fourteen pathological parameters from two hundred primary cerebral tumours are presented as vectors to a topological map. The map, consisting of a grid of neurones, learns the features of each tumour by means of a shortest Euclidean distance algorithm, after which self adaptation of the neurons occurs. An LVQ algorithm performs the final classification. Study of the map reveals that it can correctly classify tumors following their malignancy potential and their cytogenesis. The decision support system uses the network at its core and helps not only in reaching a diagnosis but also in finding the optimal way to reach that diagnosis. The usefulness of such a mapping system lies in the field of education, clinical research and medically acceptable cost reduction.

Algorithms↗