PubMed Health⌕ Search

Biomedical subjects

A de Mascarel

Publications and source records attributed to A de Mascarel.

At least 19 recordsLinked to original sources
PubMed2006

Association of serum pepsinogen with atrophic body gastritis in Costa Rica.

Individuals with atrophic gastritis (AG), especially atrophic body gastritis (ABG), are at increased risk of developing gastric cancer. Serum concentrations of pepsinogens (PG) have been proposed as markers for ABG. The aim of this study was to determine the risk factors for AG and ABG and the potential of using serum PG concentrations to detect ABG in a dyspeptic population in Costa Rica, which is one of the countries with the highest incidence and mortality rates of gastric cancer in the world. Seven biopsy specimens, a fasting blood sample and a questionnaire concerning sociodemographic factors were obtained from 501 consecutive dyspeptic patients. The serum PGI level and the PGI/PGII ratios were significantly lower in patients with ABG than in other groups (P<0.000). A cut-off point of 3.4 led to a sensitivity of 91.2% in identifying ABG, a negative predictive value of 98.1%, but a positive predictive value of only 11.2%. Helicobacter pylori were present in 93% of the patients and all those with peptic ulcers were positive. AG was associated with increased age, lower body mass index, high alcohol intake and low fruit consumption. ABG was associated with age, alcohol consumption and PGI/PGII<3.4. In dyspeptic patients with a high prevalence of H. pylori infection, serum PG levels provide an assessment of ABG but it is necessary to introduce other serological and genetic markers in order to achieve a better specificity. Those markers could be serum antibodies to H. pylori-CagA, cytokine gene polymorphisms or others.

Costa Rica↗
PubMed2006

Blastoid and common variants of mantle cell lymphoma exhibit distinct immunophenotypic and interphase FISH features.

AIMS: The recognition of blastoid variant (BV) of mantle cell lymphoma (MCL) is based on morphological criteria. Our aim was to analyse 18 MCL cases including four BV-MCL for their clinicopathological features, proliferation index, cyclin D1 and CDK4 expression and interphase fluorescence in-situ hybridization (FISH) pattern. METHODS AND RESULTS: BV-MCL versus common MCL was characterized by a shorter overall duration of response after first-line therapy (11 months versus 28 months) and shorter overall survival (20 months versus 42 months). Interphase FISH showed a t(11;14) fusion pattern in all MCL tested cases. However, the four blastoid cases were characterized by extra copies of CCND1 signals. Using additional probes of chromosomes 11, 18, 21, these signals were shown to be the result of hypotetraploidy and not of a specific amplification of the normal or the translocated CCND1 allele. Moreover, the BV-MCL cases were characterized by a combined high percentage of cells expressing cyclin D1 and/or CDK4 with a proliferation (MIB-1-Ki67) index above 50%. Such features allowed the recognition of areas of large cell transformation in the case of secondary BV-MCL. CONCLUSIONS: Since distinction between BV and common MCL is of clinical relevance, our data underline the need to add phenotypic and cytogenetic criteria to cytomorphology for a better recognition of BV-MCL.

Adult↗
PubMed2006

Splitting bone marrow trephines into frozen and fixed fragments allows parallel histological and molecular detection of B cell malignant infiltrates.

Clonality analysis of the immunoglobulin heavy chain (IgH) gene is helpful in identifying malignant B cell infiltrates in the bone marrow and is usually carried out on separate aspirates or on the same formalin-fixed decalcified bone marrow specimen. To determine whether the removal of the decalcification step would improve the molecular analysis, we first studied 12 bone marrow specimens with lymphoma infiltration split into a fixed and a small frozen fragment. Both the detection rate of IgH gene monoclonality and DNA quality were found to be superior in the frozen part than in the fixed part. Conversely, to evaluate whether the split would compromise histological analysis, we selected a series of 134 bone marrow specimens obtained from patients with small B cell lymphoma and showing IgH monoclonality on the frozen part. The histological detection rate of infiltrated or suspicious infiltrates (95%) on the fixed part was not altered by saving a frozen part.

Biopsy↗
PubMed2002

Combined analysis of T cell receptor gamma and immunoglobulin heavy chain gene rearrangements at the single-cell level in lymphomas with dual genotype.

By prospectively studying immunoglobulin heavy chain gene (IgH) and T cell receptor gamma (TCRgamma) gene rearrangements in 398 lymphoma cases, a dual genotype was observed in 13% of B cell and 11% of T cell lymphomas. According to histological subtype, the highest incidence was observed for mantle cell lymphomas (32%) and lymphoplasmacytic lymphoma (21%) among B cell lymphomas, and for angioimmunoblastic lymphoma (AILT) (46%) and Sézary syndrome (SS) (50%) among T cell lymphomas. To determine whether the dual genotype corresponds to the presence of two distinct monoclonal populations or to the presence of both rearrangements within the same lymphoma cells, single-cell microdissection was used after immunohistochemistry and a single-cell combined IgH and TCRgamma gene analysis was designed after a whole-genome amplification step. This protocol was applied to the study of two nodal B cell lymphomas (one diffuse large B cell lymphoma and one mantle cell lymphoma) and two cutaneous T cell lymphomas (one AILT and one SS). Two cases (SS and mantle cell lymphoma) were true bigenotypic lymphomas, as both IgH and TCRgamma monoclonal rearrangements were detected in the same cells. Conversely, in the diffuse large B cell lymphoma and AILT cases, large CD22+ single cells exhibited only the monoclonal IgH rearrangement but not the TCRgamma gene that was detected in CD3+ single cells. Such an approach allows the identification of true bigenotypic lymphoma among dual genotypic lymphoma. Specific genetic alterations may be further amplified from microdissected cryopreserved material, such as the t(11;14) breakpoint detected in bigenotypic B cells of the mantle cell lymphoma case.

Chromosomes, Human, Pair 11↗
PubMed2002

Detection of circulating cells expressing chromogranin A gene transcripts in patients with lung neuroendocrine carcinoma.

High grade lung neuroendocrine carcinomas, like small and large cell neuroendocrine carcinomas, pose therapeutic problems. Most initially respond to chemotherapeutic agents, but early relapses are frequent and are resistant to the presently available treatments. Our study reports for the first time the development and evaluation of a test for detecting the presence of circulating tumour cells by measuring chromogranin A gene transcripts with reverse transcriptase-polymerase chain reaction (RT-PCR) and Southern blotting. The test is specific and sensitive (detection of 10 cancer cells/ml blood), and only minimally invasive. Positivity is statistically correlated to high grade neuroendocrine carcinomas and to a poor prognosis with a 3-fold higher lethal risk. The test now needs to be assessed for its usefulness as a tool in the initial staging procedures and follow-up by comparison with the recent immunoradiometric assay (RIA) for detection of chromogranin A in the serum.

Alternative Splicing↗
PubMed2002

Conservative treatment of primary gastric low-grade B-cell lymphoma of mucosa-associated lymphoid tissue: predictive factors of response and outcome.

OBJECTIVES: Primary gastric low-grade B-cell lymphoma of mucosa-associated lymphoid tissue may regress with conservative treatment such as anti-Helicobacterpylori therapy or monochemotherapy. The aims of the present study were to analyze the predictive factors of response to anti-H. pylori treatment, to assess the effects of an adjuvant therapy in responding patients, and to evaluate an alternative therapy in nonresponding patients. METHODS: From 1995 to 2000, 48 H. pylori-infected patients with localized primary gastric low-grade B-cell lymphoma of mucosa-associated lymphoid tissue were treated with anti-H. pylori therapy. Endoscopic and endoscopic ultrasonography features and histological grading of large cells' proportion were analyzed. Eradication of H. pylori and tumoral response were assessed at 2 and 6 months, respectively. From 1996, patients in remission at 6 months were randomized to receive either chlorambucil p.o. for 6 months or no treatment. Patients who did not respond to H. pylori eradication received chlorambucil p.o. for 1 yr. RESULTS: Among the 48 treated patients, 33 (69%) were in complete (n = 28) or in partial (n = 5) remission, and 15 (31%) were in treatment failure at 6 months. H. pylori was eradicated in 47 patients. The response was not correlated with the endoscopic features or with the histological grade. In contrast, it was related to ultrasonographic features: remission was achieved in 76% of patients when no perigastric lymph node was detected versus only 33% when endoscopic ultrasonography showed presence of lymph nodes (p = 0.025). All responding patients remained in remission (median 34 months) whatever the treatment they received (no treatment or chlorambucil). Remission could be achieved with chlorambucil in 58% of the nonresponding patients to anti-H. pylori treatment. CONCLUSIONS: The major negative predictive factor of the tumoral response to anti-H. pylori treatment in patients with primary gastric low-grade B-cell lymphoma of mucosaassociated lymphoid tissue was the presence of perigastric lymph nodes on endoscopic ultrasonography. In responding patients, remission remained stable, suggesting that adjuvant chemotherapy was not useful. In patients who failed to respond to H. pylori eradication, monochemotherapy with chlorambucil proved to be efficient, but new therapeutic modalities should be evaluated to improve the control of the tumoral process.

Adult↗
PubMed2001

[How to determine the diagnosis of Helicobacter pylori infection in the elderly?].

PURPOSE: The real prevalence of Helicobacter pylori (H. pylori) infection is difficult to determine in the elderly because of the frequency of drug intake (antibiotics or anti-secretory drugs). The aim of this study was to evaluate the diagnostic performance of five tests in the elderly. METHODS: The study population consisted of consecutive patients undergoing a routine endoscopy between August 1998 and December 1999. We evaluated the diagnostic performance of four tests in all of the included patients: culture and histology of biopsy specimens, serology (ELISA) and urea breath test (13C-UBT). Detection of H. pylori antigens in stool samples (HpSA) was realized in a subgroup. Patients were considered H. pylori + when result for culture was positive or when two tests were positive. RESULTS: One hundred and sixty-seven patients were included in this study (55 men, 112 women; mean age: 85.6 +/- 5.1 years). Only 38 (22.8%) patients were H. pylori+. Test performances showed the following results: serology sensitivity: 90.9% (IC 95%: 75.6-98.1) versus 86.9% (IC 95%: 63.6-96.9) for culture versus 77.8% (IC 95%: 60.8-89.9) for histology and 74.3% (IC 95%: 56.7-87.5) for 13C-UBT. Eighty-nine (53.3%) took antibiotics or anti-secretory drugs, only 13C-UBT performances decreased significantly (sensitivity: 94.4% [72.7-99.8] versus 52.9% [27.8-77]; P < 10(-6)). When gastric or duodenal ulcer were endoscopically diagnosed in older patients, both histology and 13C-UBT could not improve the diagnosis of H. pylori infection. HpSA was realized in 107 patients (sensitivity: 74.1%, specificity: 98.7%). We showed no statistical difference between HpSA performances and drug intake. CONCLUSION: Diagnostic performances decreased in older patients especially because of drug intake.

Age Factors↗
PubMed2001

Primary digestive Richter's syndrome.

The clinical and morphologic transformation of 3 to 5% of chronic lymphocytic leukemia (CLL) to diffuse large-cell lymphoma (DLCL) is commonly referred to as Richter's syndrome. Richter's syndrome occurs mostly in lymph nodes and may represent a second neoplasm or a transformation from the same clonal population. Clinical features in six patients with digestive Richter's syndrome were recorded. Paired samples of CLL and DLCL were investigated by immunohistological analysis (n = 6) and by polymerase chain reaction (PCR) for immunoglobulin heavy-chain gene rearrangement (n = 4). Histological examination revealed the involvement of the gastrointestinal tract by DLCL of B-cell phenotype (n = 6). The same monoclonal rearrangement between CLL and DLCL was demonstrated by PCR and sequencing analyses in two patients. The monoclonal rearrangement was different between CLL and DLCL in only one case. Median survival was 22 months for five patients receiving chemotherapy, suggesting that digestive Richter's syndrome has a better prognosis than nodal Richter's syndrome. Indeed, appropriate surgical resection combined with chemotherapy led to partial or complete remission in four patients.

Aged↗
PubMed2001

Diagnosis of Helicobacter pylori infection: noninvasive methods compared to invasive methods and evaluation of two new tests.

OBJECTIVES: Current guidelines recommending Helicobacter pylori eradication treatment without performing endoscopy in certain patients highlight the importance of noninvasive tests. Our aim was to determine the accuracy of two new tests: the antigen stool test and Helicoblot 2.1 (an immunoblot used on serum) as well as the 13C urea breath test and ELISA serology in comparison to invasive tests for the pretreatment diagnosis of H. pylori infection. METHODS: Helicobacter pylori infection was diagnosed prospectively in 104 untreated patients using eight different tests. Invasive tests included culture, urease test (CLOtest), histology, and PCR; noninvasive tests included the 13C urea breath test, IgG serology (Pyloriset EIA-G), immunoblot (Helicoblot 2.1), and antigen stool detection (Premier Platinum HpSA). A predefined gold standard based on biopsy tests was used to define H. pylori status, as well as an empirical approach. RESULTS: There was no statistically significant difference between the different tests. The sensitivity of the noninvasive tests ranged between 88.9% and 95.6% (stool test: 88.9%, 95% CI: 82.7-95.1, and Helicoblot 2.1: 95.6%, 95% CI: 91.5-99.6) and the specificity ranged between 92.6 and 98.1% (stool test: 94.4%, 95% CI: 84.6-98.8, and Helicoblot 2.1: 92.6%, 95% CI: 91.5-96.2) when a predefined gold standard was used. CONCLUSIONS: Most tests had sensitivities, specificities, and predictive values >90%. The noninvasive tests are accurate for the diagnosis of H. pylori infection. Helicoblot 2.1 performed as well as the best ELISA kit. The HpSA is a promising direct noninvasive test that can be applied easily to evaluate H. pylori status.

Breath Tests↗
PubMed2001

cagA Status and eradication treatment outcome of anti-Helicobacter pylori triple therapies in patients with nonulcer dyspepsia.

The differences in eradication rates reported in clinical trials aiming to cure Helicobacter pylori infection cannot be entirely explained by the type of regimen, bacterial resistance, or lack of compliance. Using data from a clinical trial, a logistic regression model was constructed to determine whether cagA status, assessed by PCR, affects the outcome of eradication. Resistance to clarithromycin (10% of the strains) predicted failure perfectly. In the model (n = 156), a cagA-lacking strain (odds ratio [OR] = 2.2; 95% confidence interval [CI], (1.1 to 4.7), tobacco smoking OR = 3.1; 95% CI, 1.3 to 7.0), and a double dose of proton pump inhibitor in the treatment regimen (OR = 0.3; 95% CI, 0.2 to 0.7) were associated with the treatment outcome. The exact role of cagA in the outcome of H. pylori eradication therapy has not been explored. However, the type of histological lesions which it causes in the gastric mucosa may be implicated. Regardless of the mechanism involved, cagA status is a good predictive marker of eradication outcome.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

Predictive factors for regression of gastric MALT lymphoma after anti-Helicobacter pylori treatment.

BACKGROUND AND AIMS: Discrepant remission rates (41-100%) have been reported for patients with localised low grade gastric mucosa associated lymphoid tissue (MALT) lymphoma after eradication of Helicobacter pylori. The aim of this study was to explain these discrepancies and to determine the predictive factors of gastric lymphoma regression after anti- H pylori treatment. PATIENTS AND METHODS: Forty six consecutive patients with localised gastric MALT lymphoma (Ann Arbor stages I(E) and II(E)) were prospectively enrolled. All had gastric endoscopic ultrasonography and H pylori status assessment (histology, culture, polymerase chain reaction, and serology). After anti-H pylori treatment, patients were re-examined every four months. RESULTS: Histological regression of the lymphoma was complete in 19/44 patients (43%) (two lost to follow up). Median follow up time for these 19 responders was 35 months (range 10-47). No regression was noted in the 10 H pylori negative patients. Among the 34 H pylori positive patients, the H pylori eradication rate was 100%; complete regression rate of the lymphoma increased from 56% (19/34) to 79% (19/24) when there was no nodal involvement at endoscopic ultrasonography. There was a significant difference between the response of the lymphoma restricted to the mucosa and other more deep seated lesions (p<0.006). However, using multivariate analysis, the only predictive factor of regression was the absence of nodal involvement (p<0.0001). CONCLUSION: In H pylori positive patients with localised gastric MALT lymphoma, carefully evaluated and treated without any lymph node involvement assessed by endoscopic ultrasonography, complete remission of lymphoma was reached in 79% of cases.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2000

Small B-cell lymphoproliferative disorders: an overview of diagnostic approach.

Despite their common origin from the B-cell mature lymphoid system, small B-cell lymphomas/leukaemias represent in fact an heterogeneous group of diseases. Recent advances in immunohistochemistry and molecular techniques have improved our knowledge of the immune system and lymphoid neoplasms. An international consensus has been recently reached among pathologists and clinicians, that recognises clinico-pathological entities which are defined by a combination of morphological, immunophenotypical, genetic and clinical features. In each entity, a range of histological grade and clinical aggressiveness can be encountered. Recognition of these entities, combined with clinical prognostic factors has clinical implications in terms of response to treatment and prognosis. The purpose of this paper is to focus on a practical approach, either clinical or pathological, of the diagnosis of small B-cell lymphoma/leukaemia.

Humans↗
PubMed2000

Positive effect of rebamipide on gastric permeability in mice after eradication of Helicobacter felis.

BACKGROUND: Despite Helicobacter pylori eradication, gastric inflammation persists for months or years. Preliminary results have indicated that an increase in gastric permeability could be one reason. Our aim was to evaluate the effect of a mucosal protective drug, rebamipide, on gastric permeability in a model of H. felis-infected mice. METHODS: Thirty-three C57/BL6 mice were inoculated with H. felis, and seven controls were kept non-inoculated. After 2 months 20 infected mice were treated with omeprazole, amoxicillin, and clarithromycin for 1 week and then for 4 weeks with either rebamipide (n = 9) or placebo (n = 11). The 13 remaining mice were kept untreated. After cessation of treatment, a fragment of antrum obtained from each mouse was mounted in a small Ussing chamber to study the electric resistance of the tissue (R) and antral permeability. RESULTS: No modification of the paracellular permeability (R, JNa, JMan) was observed in either group. However, the transcellular permeability to horseradish peroxidase (HRP) was significantly increased in H. felis-infected non-treated mice (1131 +/- 463, 948 +/- 339, and 182 +/- 312 ng/h x cm2) as compared with non-infected controls (469 +/- 262, 458 +/- 261, and 10 +/- 6 ng/ h x cm2, for J3H-HRP, JD, and JHRPi, respectively) (P < 0.003). Eradication of the bacteria by antibiotics without subsequent treatment with rebamipide led to a non-significant decrease in the HRP fluxes. However, when rebamipide was used after the antibiotic treatment, a significant (P < 0.01) decrease in HRP fluxes as compared with non-treated mice was observed. CONCLUSIONS: These results confirm that gastric permeability to macromolecules remains increased despite H. felis eradication and show that rebamipide can facilitate the normalization of gastric permeability to macromolecules after bacterial eradication.

Alanine↗
PubMed2000

Long-term effects of Helicobacter pylori eradication on gastric antral mucosa in duodenal ulcer patients.

OBJECTIVES: The aim of this study was to assess the consequences of prolonged Helicobacter pylori eradication on gastric antral mucosa in duodenal ulcer patients. PATIENTS AND METHODS: Forty-three duodenal ulcer patients with confirmed H. pylori eradication after one year of follow-up were included in this retrospective study. Before H. pylori eradication and during the follow-up, four antral prepyloric biopsy samples were taken for histopathological examination and culture. Histopathological lesions were graded semi-quantitatively according to the updated Sydney System for activity, chronic inflammation, glandular atrophy and intestinal metaplasia (IM), as well as presence of lymphoid follicles. RESULTS: After a mean follow-up of 43 +/- 23 months, H. pylori eradication statistically improved all gastritis scores, including the atrophy score and the lymphoid follicle score but excluding the IM score. H. pylori eradication resulted in normalization of gastric mucosa in 51.2% of patients and a significantly lower proportion of patients with non-atrophic gastritis and atrophic gastritis without IM. Atrophy totally disappeared in 16/29 patients (55.2%) in whom IM was absent. No predictive factor for regression of atrophy or normalization of gastric mucosa was identified. CONCLUSION: In duodenal ulcer patients, prolonged absence (more than one year) of H. pylori can lead to normalization of the antral mucosa and the disappearance of mucosa-associated lymphoid tissue, as well as the regression of antral atrophy. Long-term studies involving selected patients with atrophy and IM which persist after H. pylori eradication are needed to determine the potential benefits of treating H. pylori gastritis with regard to gastric cancer prevention.

Adult↗
PubMed2000

Intrasinusoidal bone marrow infiltration revealing intravascular lymphomatosis.

Intravascular lymphoma is a rare, often fatal disease characterized by a widespread intravascular proliferation of neoplastic lymphoid cells. Dermatological and bizarre neurological manifestations usually predominate. We report a case of intravascular lymphomatosis with an exceptional clinical presentation showing splenomegaly combined with early bone marrow involvement. The diagnosis was made on bone marrow biopsy examination using both immunohistochemistry and molecular biology analysis. We stress the histopathological features of bone marrow involvement by intravascular lymphoma which allow the prompt recognition of this disease. Early systemic chemotherapy, which represents the only chance of remission in such an aggressive disease, can then be initiated.

Aged↗
PubMed1999

Expression of neurotrophins and their receptors in human bone marrow.

The expression of neurotrophins and their receptors, the low-affinity nerve growth factor receptor (p75LNGFR) and the Trk receptors (TrkA, TrkB, and TrkC), was investigated in human bone marrow from 16 weeks fetal age to adulthood. Using reverse transcription-polymerase chain reaction, all transcripts encoding for catalytic and truncated human TrkB or TrkC receptors were detected together with trkAI transcripts, whereas trkAII transcripts were found only in control nerve tissues. Transcripts for the homologue of the rat truncated TrkC(ic113) receptor were identified for the first time in human tissue. Stromal adventitial reticular cells were found immunoreactive for all neutrophin receptors. In contrast, hematopoietic cell types were not immunoreactive for p75LNGFR but showed immunoreactivity for one or several Trk receptors. TrkA immunoreactivity was found in immature erythroblasts. Catalytic TrkB immunoreactivity was observed in eosinophilic metamyelocytes and polymorphonuclear cells. Truncated TrkB immunoreactivity was found in erythroblasts and megacaryocytes. Immunoreactivity for both catalytic and truncated TrkC receptor was observed in promyelocytes, myelocytes, some polymorphonuclear cells and megacaryocytes. Neutrophin transcript levels appeared higher at fetal than at adult stages, no variation in Trk family transcript levels was observed. The local expression of neurotrophin genes suggests a wide range of paracrine and/or autocrine mode of action through their corresponding receptors within the bone marrow.

Adult↗