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B Maes

Publications and source records attributed to B Maes.

At least 55 records · Page 3Linked to original sources
PubMed2000

Analysis of the P53, RB/D13S25, and P16 tumor suppressor genes in marginal zone B-cell lymphoma: An interphase fluorescence in situ hybridization study.

The genetic mechanisms underlying the genesis, disease progression, and high-grade transformation of marginal zone B-cell lymphoma (MZBCL) are poorly understood. We analyzed 33 cases of histologically and immunophenotypically well-characterized MZBCL (12 extranodal, 11 nodal, and 10 splenic MZBCL; 27 at primary diagnosis and six during the course of disease) by dual-color interphase fluorescence in situ hybridization (FISH) for deletions of tumor suppressor genes. We investigated loci known to play a role in the genesis or disease progression of other subtypes of lymphoid malignancies, namely the P53 gene (17p13), the retinoblastoma gene (RB, 13q14), the D13S25 locus (13q14), and the P16(INK4A) gene (9p21). Heterozygous deletions of P53 were detected in three out of the 33 cases, including two splenic and one extranodal MZBCL. One of these patients was analyzed at primary diagnosis and two during the course of disease. Heterozygous deletions of the RB gene (nodal MZBCL) and D13S25 (splenic MZBCL) were found in one case each. P16 deletions were not detected in any of our cases. We conclude that deletions of the analyzed tumor suppressor genes are relatively rare in MZBCL, which contrasts with the findings in some other subtypes of NHL.

Aged↗
PubMed2000

Increased proteasome degradation of cyclin-dependent kinase inhibitor p27 is associated with a decreased overall survival in mantle cell lymphoma.

Mantle cell lymphoma (MCL) is an aggressive neoplasm characterized by the deregulated expression of cyclin D1 by t(11;14). The molecular mechanisms responsible for MCL's clinical behavior remain unclear. The authors have investigated the expression of p53, E2F-1, and the CDK inhibitors p27 and p21 in 110 MCLs, relating their expression to proliferative activity (Ki-67). For comparison, they have similarly analyzed low-grade (12 MALT, 16 CLL/SLL) and high-grade (19 DLCL) lymphomas. p53 was detected more frequently in large-cell MCL (l-MCL; 5 of 7) than in classical MCL (s-MCL; 13 of 103) and DLCL (8 of 19). In MCL and DLCL, the percentage of E2F-1+ nuclei was high, correlating with high Ki-67 expression. Most MCLs (91 of 112) and DLCLs (12 of 19) showed a loss of p27; MALT and CLL/SLL, however, were p27 positive. Reverse transcription-polymerase chain reaction and in vitro protein degradation assays demonstrated that MCLs have normal p27 mRNA expression but increased p27 protein degradation activity via the proteasome pathway. Correlation of MCL p53 and p27 expression with clinical data showed an association between reduced overall survival rates and the overexpression of p53 (P =.001), the loss of p27 (P =. 002), or both. Loss of p27 identified patients with a worse clinical outcome among p53 negative cases (P =.002). These findings demonstrated that MCL has a distinct cell cycle protein expression similar to that of high-grade lymphoma. The loss of p27 and the overexpression of p53 in MCL are prognostic markers that identify patients at high risk. The demonstration that low levels of p27 in MCL result from enhanced proteasome-mediated degradation should encourage additional clinical trials. (Blood. 2000;95:619-626) (Blood. 2000;95:619-626)

B-Lymphocytes↗
PubMed2000

Magnetic resonance imaging in the assessment of urologic disease: an all-in-one approach.

The aim of this study was to evaluate an "all-in-one" MR procedure to examine the kidneys, the renal vascular supply and renal perfusion, and the urinary tract. In 64 patients (58 with urologic disease and 6 healthy volunteers), MR was performed including: (a) T1- and T2-weighted imaging; (b) 3D contrast-enhanced MR angiography (MRA), including the renal arteries, renal veins, as well as renal perfusion; and (c) 3D contrast-enhanced MR urography (MRU) in the coronal and sagittal plane. For the latter, low- and high-resolution images were compared. Prior to gadolinium injection, 0.1 mg/kg body weight of furosemide was administered intravenously. The results were compared with correlative imaging modalities (ultrasonography, intravenous urography, CT), ureterorenoscopy and/or surgical-pathologic findings. Visualization of the renal parenchyma, the vascular supply, and the collecting system was adequate in all cases, both in nondilated and in dilated systems and irrespective of the renal function. One infiltrating urothelial cancer was missed; there was one false-positive urothelial malignancy. Different MR techniques can be combined to establish an all-in-one imaging modality in the assessment of diseases which affect the kidneys and urinary tracts. Continuous refinement of the applied MR techniques and further improvements in spatial resolution is needed to expand the actual imaging possibilities and to create new tracts and challenges in the MR evaluation of urologic disease.

Adult↗
PubMed2000

The product of the t(11;18), an API2-MLT fusion, marks nearly half of gastric MALT type lymphomas without large cell proliferation.

Recently we demonstrated that the t(11;18)(q21;q21) associated with extranodal marginal zone B cell lymphomas of MALT type results in the expression of a chimeric transcript fusing 5' API2 on chromosome 11 to 3' MLT on chromosome 18. Here we report the development of an RT-PCR approach for the detection of the API2-MLT fusion transcript and its application for the analysis of 58 cases of gastric lymphoma. Initially nested PCR amplification was combined with Southern analysis using internal API2 and MLT probes. A genuine API2-MLT fusion transcript of variable length was demonstrated in 11 out of 58 cases. Sequence analysis revealed that in all cases the breakpoint on chromosome 11 occurred between exons 7 and 8 of the API2 gene. In contrast, the breakpoints on chromosome 18 appeared to be heterogeneous as fusions to bp 814, 1123, and 1150, respectively, of MLT were observed. These observations allowed us to work out a highly sensitive diagnostic test for the API2-MLT fusion on an ABI Prism 7700 sequence detector that confirmed the results of our initial approach. The API2-MLT fusion was found in 48% of gastric marginal zone cell lymphomas of MALT type that did not contain a large cell component and it was lacking in all other lymphomas of the stomach.

Caspases↗
PubMed2000

The product of the t(11;18), an API2-MLT fusion, is an almost exclusive finding in marginal zone cell lymphoma of extranodal MALT-type.

BACKGROUND: Extranodal marginal zone cell lymphoma (MZCL) of MALT-type share similar features with nodal and splenic MZCL regarding morphology and immunophenotype. At the genetic level, recent cytogenetic studies have shown that t(11;18) is a recurring abnormality in extranodal MALT-type MZCL but has hitherto never been reported in nodal or splenic MZCL. The aim of the present study was to determine the prevalence of t(11;18) in a large series of nodal, splenic and extranodal MALT-type MZCL, using a sensitive real-time RT-PCR method. MATERIALS AND METHODS: Ninety-three MZCL cases were divided on clinical grounds into 61 extranodal MALT-type, 19 splenic and 12 nodal MZCL. One case that presented with a massive splenomegaly but for which also gastro-intestinal localisations were found, was left unclassified. A real-time RT-PCR method for the detection of the API2-MLT fusion resulting from t(11;18) was performed on RNA extracted from frozen tissue sections. RESULTS: The API2-MLT fusion was detected in 12 cases, which were all extranodal MALT-type lymphomas of the stomach, except for one case. The remaining positive case was the unclassified case, for which the translocation was detected in the spleen and in hilar lymph node tissue. CONCLUSIONS: While similarities between MZCL from different anatomic sites have lend us to propose that all MZCL have a common normal counterpart, the almost exclusive detection of t(11;18) in gastric MALT-type lymphoma favours its recognition as a separate lymphoma entity. The absence of the translocation in nodal and splenic MZCL challenges the idea of these lymphomas being secondary to MALT-type lymphomas of the gut. The unclassified case illustrates the inadequate approaches available at present to identify and define the various MZCL.

Apoptosis↗
PubMed2000

Developing a model for quality evaluation in residential care for people with intellectual disability.

The present article describes the development of a general model for the evaluation, enhancement and assurance of quality of care processes in residential facilities for children and adults with intellectual disability. The framework is based on current theories regarding quality of life and quality evaluation, on a consensus between several participants in Delphi discussion-rounds, and on a questionnaire for care providers and clients in all Flemish residential facilities. The model describes 13 quality standards and a list of indicators concerning organization and support interventions. Facilities may use this set of criteria and indicators in several ways within a continuous and dynamic system of internal quality assurance. Finally, the prospects of and conditions for the implementation of this model are discussed.

Adult↗
PubMed2000

Limited cutaneous systemic sclerosis associated with MPO-ANCA positive renal small vessel vasculitis of the microscopic polyangiitis type.

Renal disease in systemic sclerosis may present in various patterns. A 66-year-old woman with a history of longstanding limited cutaneous systemic sclerosis of the CREST syndrome variant presented with a sudden left foot drop and rapidly progressive renal insufficiency associated with mild proteinuria, a nephritic urine sediment, and a urinary output of 900 mL/d. There was no history of intake of D-penicillamine, and there were no signs of malignant arterial hypertension or microangiopathic hemolytic anemia. Renal histology showed a small vessel vasculitis of the microscopic polyangiitis type. Serologic tests showed a marked increase of antineutrophil cytoplasmic antibodies with a perinuclear pattern and an elevated titer of antimyeloperoxidase antibodies. No clinical or laboratory signs of Sjögren's syndrome were present. This clinical report adds new information to the spectrum of renal disease in systemic sclerosis. It discusses the association between systemic sclerosis and small vessel vasculitis of the microscopic polyangiitis type as well as the possible meaning of serologic markers.

Acute Kidney Injury↗
PubMed2000

Evaluation of B cell lymphoid infiltrates in bone marrow biopsies by morphology, immunohistochemistry, and molecular analysis.

AIMS: Morphological criteria to distinguish between reactive and neoplastic B cell lymphocytoid infiltrates in trephines have been defined but are not always reliable. Polymerase chain reaction (PCR) analysis of the CDR3 region of the immunoglobulin heavy chain (IgH) gene which, by demonstrating monoclonality, can provide additional arguments in favour of lymphoid malignancy is now frequently used for the detection and follow up of B cell lymphoma (NHL). The aim of this study was to investigate the usefulness of morphological findings in bone marrow biopsies in comparison with data obtained by PCR analysis. METHODS: Eighty nine bone marrow biopsies displaying lymphoid infiltrates were evaluated by morphology and immunohistochemistry as well as by CDR3-PCR using consensus framework 3 (FRW3) and JH primers. RESULTS: The presence of a clonal B cell proliferation was demonstrated by PCR analysis in 45 biopsies, including 21 samples considered to be positive, 17 to be suspicious, and seven to be negative by morphology. In the remaining 44 trephines we found no evidence of clonality, although 12 of these trephines were thought to be positive by morphology. CONCLUSIONS: These results, revealing an incomplete correlation between CDR3-PCR data and immunomorphological findings, indicate that molecular analysis may be more sensitive and specific in general. However, false negative PCR results do occur, which emphasises the necessity to combine both diagnostic tools in the evaluation of lymphoid infiltrates.

Biopsy↗
PubMed2000

Phenotypic checklist to screen for fragile X syndrome in people with mental retardation.

The development of a phenotypic checklist for identifying people with fragile X syndrome is described. The checklist was designed to identify people with developmental disabilities of unknown causes for molecular genetic testing for fragile X syndrome. The list consists of 28 items (7 on physical characteristics and 21 on behavioral features). Validation data were collected for 110 boys and men with fragile X syndrome and for 79 members of a control group, matched for CA, level of cognitive development, and social (mal)adaptation. On the basis of checklist results, those boys who are likely to be diagnosed as having fragile X syndrome can be identified. The screening list can be considered to be a consistent, reliable, and valid instrument.

Adolescent↗
PubMed2000

[Positive antithyroglobulin antibodies in patients with differentiated thyroid carcinoma. What significance?].

The aim of this retrospective study was to determine the predictive value of antithyroglobulin antibodies (TgAb) in 238 patients with undetectable thyroglobulin after whole thyroidectomy for differentiated cancer and ablative dose of radioiodine. TgAb titers were elevated in 30 patients with undetectable Tg level after withdrawal of T4 treatment. In 21 patients, initially positive TgAb titers became undetectable without clinical event within 3-84 months after therapy (median 12 months). In 2 cases, TgAb levels became undetectable whereas scintigraphy detected pathologic fixations. In 7 cases, high levels of TgAb titles remained unchanged 5 years after primary diagnosis In 3 of them, clinical course and distant metastases, were associated with an increased TgAb level despite normal Tg values. The investigation confirmed that serum TgAb measurement is one of the most important tools for the follow-up of patients with differentiated thyroid cancer. The presence of metastatic thyroid tissue has to be suspected in positive TgAb patients.

Adolescent↗
PubMed2000

Crescentic glomerulonephritis complicating the course of a hypocomplementemic urticarial vasculitis.

The authors report a case of crescentic glomerulonephritis leading to end-stage renal failure in a patient affected by a hypocomplementemic urticarial vasculitis (HUV). The patient's clinical course was characterized by the survey of several episodes of extra-renal vasculitis. We emphasize that HUV commonly considered as a limited form of vasculitis might in some cases have a dramatic evolution.

Adult↗
PubMed1999

Guidelines for subtyping small B-cell lymphomas in bone marrow biopsies.

In this review, we summarise the patterns of bone marrow involvement by small B-cell lymphomas. Both our own experience and the literature reports on the subject show that each subtype of lymphoma can be recognised from a distinct combination of a suggestive growth pattern and a particular cytological composition. A predominantly paratrabecular infiltrate composed of centrocytes is characteristic of follicle centre cell lymphoma. In mantle cell lymphoma, prominent intertrabecular nodules, each consisting of a monotonous proliferation of small to intermediate-sized lymphoid cells with an irregular nucleus, are the most frequent finding. Marginal zone cell lymphoma displays similar intertrabecular nodules, but the infiltrates are rather loose and polymorphic, whereas the lymphoid cells exhibit monocytoid features. Diffuse infiltrates composed of small lymphocytes with clumped chromatin, of plasma cells with Dutcher bodies and of mast cells are observed in most cases of lymphoplasmacytoid lymphoma/immunocytoma. Although chronic lymphocytic leukaemia / small lymphocytic lymphoma can present with a comparable pattern of bone marrow involvement, an interstitial infiltrate of small lymphoid cells is usually observed. A comparable interstitial pattern also prevails in hairy cell leukaemia. This lymphoma subtype, however, can be readily identified by the abundant clear cytoplasm of the neoplastic cells, erythrocyte extravasation and associated abnormalities in the haematopoietic series.

Algorithms↗
PubMed1999

IgA antiglomerular basement membrane disease associated with bronchial carcinoma and monoclonal gammopathy.

Antiglomerular basement membrane (anti-GBM) disease is characterized by a linear deposition of immunoglobulins along the glomerular basement membrane. A 67-year-old man with a recently discovered monoclonal gammopathy of unknown significance (MGUS) presented with microscopic hematuria, nephrotic-range proteinuria, and rapidly deteriorating renal function after a pneumonia. Renal histology showed a crescentic glomerulonephritis; immunohistology showed intense linear staining of the GBM with immunoglobulin A (IgA) and moderate linear staining with kappa and lambda light chains. Screening for systemic disease, including diabetes mellitus, lupus erythematodes disseminatus, cryoglobulinemia, was negative. Serological tests for detection of anti-GBM antibodies were positive for IgA class and negative for IgG. Further examination indicated a bronchial carcinoma T2N2M0. This clinical report adds new information to the spectrum of anti-GBM disease and suggests that neoplasia may be associated with unusual exposure of and/or immune response to epitopes in the GBM.

Aged↗
PubMed1999

Application of the International Prognostic Scoring System for myelodysplastic syndromes.

BACKGROUND: In March 1997 an international workshop introduced a new International Prognostic Scoring System (IPSS) for MDS. The goal of the present study was to apply the IPSS to a large group of MDS patients from one centre and to compare it to the FAB-classification. PATIENTS: One hundred eighty-four MDS patients were included on the basis of similar criteria as used by the workshop but some of them (30) received AML-type therapy. RESULTS: The IPSS separated our patients into distinctive prognostic subgroups (P = 0.0001). Median survival was respectively 6.5, 2.6, 1.3 and 0.75 years for the low-risk (22% of patients), the intermediate-1-risk (INT-1) (46%), the intermediate-2-risk (INT-2) (25%) and the high-risk group (7%). The IPSS also discriminated within each of the FAB-categories: RA patients (58 patients) were present in low-risk, INT-1-risk and INT-2-risk subgroups, RARS patients (23) were separated into low-risk and INT-1-risk subgroups. RAEB patients (53) were distributed predominantly between INT-1-risk and INT-2-risk groups, RAEB-t patients (23) between INT-2-risk and high-risk subgroups. CMML patients (27) were present in the low-risk, the INT-1-risk and the INT-2-risk group. CONCLUSIONS: Our results confirm the effectiveness of the IPSS in predicting clinical outcome in MDS patients and indicate that it is an improved method compared to the FAB-classification.

Age Factors↗
PubMed1999

Neuropsychological, learning and psychosocial profile of primary school aged children with the velo-cardio-facial syndrome (22q11 deletion): evidence for a nonverbal learning disability?

In this exploratory study, the neuropsychological and learning profile of nine primary school age children with velo-cardio-facial syndrome (VCFS) was studied by systematic neuropsychological testing. In five out of nine children, the following profile was found: a VIQ-PIQ discrepancy (in favor of the VIQ), significantly better scores (.05 level) for reading (decoding) and spelling compared to arithmetic, deficient tactile-perceptual skills (difficulties mainly on the left side of the body), weak but not deficient visual-perceptual abilities, deficient visual-spatial skills, extremely poor psychomotor skills (gross motor skills more deficient than fine motor skills), problems with processing of new and complex material, poor visual attention, good auditory memory and relatively good language skills. These findings correspond to the pattern of neuropsychological assets and deficits that has been described for the syndrome of nonverbal learning disabilities (NLD) (Rourke, 1987, 1988, 1989, 1995). The psychosocial profile of all nine children with VCFS also correspond to that of children with NLD. Further studies on the relationship between cognitive function, behavior, psychiatric disorder and abnormalities in brain anatomy in young people with VCFS will be needed. In clinical practice, it is worthwhile exploring in greater depth the neuropsychological functions of children with VCFS to rule out NLD, since they may benefit from specific remediation following the learning principles of the NLD-treatment.

Attention↗
PubMed1999

Validation of the lactose-[13C]ureide breath test for determination of orocecal transit time by scintigraphy.

UNLABELLED: The breath test using oral administration of a 13C-labeled substrate, lactose-ureide (LU), to measure orocecal transit time (OCTT) was validated against 99mTc-scintigraphy. Although LU is not absorbed in the human small intestine, colonic bacteria readily metabolize LU, producing 13C-labeled CO2. The time at which 13CO2 appears in breath corresponds to the OCTT. METHODS: Twenty-two healthy volunteers ingested a meal labeled with 99mTc and 13C-LU. Scintigraphy was performed over 8 h at time intervals of 10 or 15 min. OCTT with scintigraphy was defined as the time at which at least 10% of the label had entered the colon. Breath samples were obtained every 10-15 min for 10 h and measured by isotope ratio mass spectrometry. OCTT was defined as the time of first significant increase above baseline. The results were compared using correlation and Altman-Bland statistics. RESULTS: OCTT results from scintigraphy (mean OCTT = 283+/-53 min) and breath test (mean OCTT = 292+/-58 min) correlated well (r = 0.94). Altman-Bland statistics showed close agreement between scintigraphy and breath test. No significant difference between male and female subjects was observed. CONCLUSION: The breath test using 13C-LU is a valid alternative to scintigraphy techniques for measuring OCTT.

Adult↗