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Biomedical subjects

F Bernardi

Publications and source records attributed to F Bernardi.

At least 145 records · Page 8Linked to original sources
PubMed1995

Molecular bases of CRM+ factor X deficiency: a frequent mutation (Ser334Pro) in the catalytic domain and a substitution (Glu102Lys) in the second EGF-like domain.

The presence of gene lesions in coagulation factor X (FX, Stuart factor) was investigated in asymptomatic subjects with FX deficiency characterized by the presence of dysfunctional molecules in plasma, as demonstrated by the discrepancy between clotting activity and antigen level. A missense mutation (Ser334Pro) in the catalytic domain was found in three unrelated families in both the homozygous and the heterozygous conditions, and also in the compound heterozygous form with the substitution of Lys for 102 Glu. None of the mutations was detected in 40 unrelated subjects from the same geographic area. The Ser334Pro mutation affects a serine protease region characterized by extensive variation in the coagulation factors but conserved in mammalian factor X molecules. The Glu102Lys mutation affects a residue of the second EGF-like module also conserved in protein C. Both mutated residues are surface-exposed and found in protein regions suggested to be involved in macromolecular interactions which are impaired in the dysfunctional molecules.

Base Sequence↗
PubMed1995

Resistance to activated protein C in healthy women taking oral contraceptives.

Resistance to activated protein C (APC) is at present considered the most frequent laboratory abnormality in patients with deep-vein thrombosis. An increased risk for venous thrombosis is associated to the use of oral contraceptives (OC). We studied APC sensitivity in 50 healthy women taking OC and in 50 healthy controls, matched for age, smoking habit, educational and social levels, and the main biochemical routinary parameters. Subjects with a personal or familial history of thrombosis and also with chronic or acute diseases were excluded. Protein C, protein S, antithrombin III and lupus anticoagulant activity (LAC) were also evaluated. Increased fibrinogen and protein C levels, decreased protein S. and shortened PT and APTT were also observed in women taking OC. APC sensitivity ratio (APC-SR) was significantly lower in the OC group than in a control group (2.6 +/- 0.38 v 2.81 +/- 0.35, P < 0.01). Seven of eight women with APC ratio < or = 2 (APC resistant) were OC users: the difference of prevalence was statistically significant (chi-squared test, P < 0.05). Only two out of eight women were found heterozygous for the Leiden factor V mutation. Two APC-resistant women without the Leiden mutation subsequently discontinued OC and both then normalized their APC-SR. We conclude that acquired factors, i.e. oral contraceptives, may play an important role in determining plasma APC resistance.

Adult↗
PubMed1995

Monoclonal gammopathy of undetermined significance: chromosome changes are a common finding within bone marrow plasma cells.

We used two indirect approaches [image analysis (Feulgen staining) and fluorescence in situ hybridization (FISH)] to study bone marrow plasma cells (BMPC) in 28 patients fulfilling criteria for MGUS. 61% of patients were found to be aneuploid after image analysis: three were hypodiploid and 14 were hyperdiploid. 12/14 hyperdiploid patients also revealed abnormalities after FISH: 12-72% of BMPC exhibited trisomy for at least one of chromosomes 3, 7, 9 and 11. These latter chromosomes are the four chromosomes most frequently implicated (in the shape of trisomy) in MM, confirming the tight relationship between both conditions. After a median follow-up of 19 months (12-41 months) no patient developed overt MM. Also, we failed to find any relationship between currently available biological parameters and DNA findings. As literature data give a transformation rate of 20-30% after a follow-up of 20-35 years, it is worth presuming that some aneuploid patients will evolve to MM, whereas others (also with aneuploid bone marrow plasma cells) will never develop cancer. Our findings indicate that numeric abnormalities, as they are shared both by MGUS and MM patients, are certainly an additional or a prerequisite event, but are not related to an overt disease. They also emphasize the importance of cytogenetic study in the pathophysiology of MGUS.

Adult↗
PubMed1995

CD19 and immunophenotype of bone marrow plasma cells in monoclonal gammopathy of undetermined significance.

AIMS: To determine whether a particular phenotype or antigen is preferentially related to monoclonal gammopathies of undetermined significance (MGUS). METHODS: Bone marrow specimens from 56 patients with MGUS were stained immunocytochemically (ABC peroxidase) for CD38, CD56, CD9, CD10, CD19, CD20, CD22, and MB2. Specimens from patients recently diagnosed with multiple myeloma and reactive bone marrow samples were studied in parallel. RESULTS: CD38 was expressed on all plasma cells from all MGUS samples tested, while 36% were positive for CD56, CD9 and MB2 were both expressed strongly; CD20 was moderately expressed, and staining for CD10 and CD22 was uncommon. For these five B cell antigens there was no clear difference between their expression in MGUS and in multiple myeloma. A great difference was found for CD19: in MGUS this antigen was expressed on 2-91% of plasma cells (mean 35%) and 77% patients had > 10% positive plasma cells; in multiple myeloma its expression was low and only 12% patients had > 10% positive plasma cells. When these results were converted to numbers of CD19 positive plasma cells per 100 nucleated bone marrow cells, reactive bone marrow and MGUS specimens had a similar number of positive plasma cells. There was no correlation between expression of any of the antigens tested. CONCLUSIONS: Many of the so-called pre-B, B or activation antigens are present on plasma cells from MGUS specimens, and expression of CD9, CD10, CD20, CD22, MB2, and CD38 in MGUS was very similar to that in multiple myeloma. CD56 was frequently expressed in MGUS. In this series CD19 was highly expressed in MGUS but not in multiple myeloma. Plasma cells bearing this antigen could represent the non-neoplastic process and determination of its expression could be useful for the diagnosis of MGUS.

Antigens, CD↗
PubMed1995

Protein S mRNA in patients with protein S deficiency.

A protein S gene polymorphism, detectable by restriction analysis (BstXI) of amplified exonic sequences (exon 15), was studied in seven Italian families with protein S deficiency. In the 17 individuals heterozygous for the polymorphism the study was extended to platelet mRNA through reverse transcription, amplification and densitometric analysis. mRNA produced by the putative defective protein S genes was absent in three families and reduced to a different extent (as expressed by altered allelic ratios) in four families. The allelic ratios helped to distinguish total protein S deficiency (type I) for free protein S deficiency (type IIa) in families with equivocal phenotypes. This study indicates that the study of platelet mRNA, in association with phenotypic analysis based upon protein S assays in plasma, helps to classify patients with protein S deficiency.

Alleles↗
PubMed1995

Swyer-James syndrome: bronchoalveolar lavage findings in two patients.

Swyer-James syndrome (SJS) is a rare constrictive bronchiolitis that appears to be the result of acute bronchiolitis in infancy or early childhood. In the present study the cytological and immunophenotypical profile of bronchoalveolar lavage (BAL) was studied in two patients with SJS who showed a different spectrum of clinical outcome. The total BAL yield was markedly increased in the patient with chronic cough and acute episodes of dyspnoea but not in the patient with decreased exercise tolerance and longer duration of disease. In the two patients, the differential cell counts in percentage were characterized by a significant increase of neutrophils and a slight increase of lymphocytes. The analysis of lymphocyte subsets showed a significant increase of CD8+ cells (T-suppressor-cytotoxic) in both cases, resulting in a decreased CD4/CD8 ratio. In addition, an increase of cells bearing a B-phenotype (CD19+ cells) was noted in the fluid recovered from the patient with chronic cough and acute episodes of dyspnoea. In conclusion, our data suggest that SJS is an active process with inflammatory characteristics. Further studies are needed to explain the mechanism leading to the expansion in situ of immunocompetent cells.

Adolescent↗
PubMed1995

Interphase fluorescence in situ hybridization (FISH) as a powerful tool for the detection of aneuploidy in multiple myeloma.

Conventional cytogenetic (CC) studies performed in multiple myeloma (MM) are difficult because of the low proliferation rate of plasma cells (PC). The purpose of this study was to compare results obtained by CC and by FISH for the detection of numeric chromosomal changes in patients with MM. PC DNA content, CC and interphase FISH analysis were performed on 29 consecutive patients with MM. Fifteen patients (control group) had known Cytogenetic abnormalities identified by CC. The other 14 patients (study group) had a normal karyotype but an abnormal DNA content. Bone marrow material prepared for CC or cytospin slides were probed with classical satellite III or alpha satellite DNA sequences for chromosomes 3, 7, 8, 9, 11 and 15 (chromosomes 3, 7, 9, 11, 15 probes for hyperdiploid patients and the chromosome 8 probe for hypodiploid patients). In the control group, an unexplained discrepancy between CC and FISH occurred for only one chromosome in one patient. Also in this group, four patients had only one abnormal cell by CC and the numeric changes in these patients were always confirmed by FISH analysis. In the study group, FISH analysis showed an abnormal result in all but one patient. From these data, we conclude that FISH improves the detection of cytogenetic abnormalities in multiple myeloma. Using commercially available DNA probes for the most frequent numeric changes and slides for CC or cytospin slides, we demonstrated abnormal cytogenetics by FISH in 28/29 patients. In further studies, use of FISH could permit a more accurate description of numeric changes and their prognostic value in MM as well as an approach to clonal evolution. It would also be of interest in the study of monoclonal gammopathies of undetermined significance.

Adult↗
PubMed1994

Image analysis in multiple myeloma at diagnosis. Correlation with cytogenetic study.

The DNA content of plasma cells (DNA Index or DI) was determined after Feulgen reaction using computed image analysis in 46 patients with multiple myeloma at diagnosis. Aneuploidy was found in 40/46 (87.0%) patients; 27 (58.7%) were hyperdiploid (DI = 1.05-1.45), 11 (24.0%) were hypodiploid (DI = 0.90-0.95), and two (4.3%) were biclonal. Cytogenetic study showed at least one abnormal mitosis in 21/46 (45.7%) cases. All patients with numeric changes had aneuploid DI, and thus confirmed DI > or = 1.05 and DI < or = 0.95 as good limits for aneuploidy with image analysis. Since abnormal karyotypes were observed mainly in stages II and III (55.6% and 54.5%, respectively) rather than in stage I (26.7%), aneuploid DI was found in most patients in all three stages, namely in all 15/15 (100%) patients in stage I. The prognostic value of aneuploidy was difficult to ascertain in our series. Hypodiploidy or DI > 1.15 was not especially associated with aggressive disease, as it was observed in 7/15 patients in stage I; however, with the same limits, patients with stages II and III were refractory to first-line chemotherapy. Image analysis is a highly sensitive method showing aneuploidy in most patients with MM at diagnosis and, in association with cytogenetic study, may help to better understand the pathogenesis of the disease. The independent prognostic value of aneuploidy was not fully established in this report.

Aneuploidy↗
PubMed1994

Two cases of t(1;16)(p11;p11) in multiple myeloma: confirmation by chromosome painting.

Two patients with multiple myeloma and an unbalanced translocation, t(1;16)(p11;p11), are reported. The fluorescence in situ hybridization (FISH) technique was used in one patient to confirm the translocation. To our knowledge, t(1;16)(p36;q13) and t(1;16)(q21;p13), but not t(1;16)(p11;p11), had been reported previously in multiple myeloma. Our results suggest that FISH is useful to characterize structural abnormalities and identify marker chromosomes in multiple myeloma where analysis with conventional cytogenetics is often difficult.

Aged↗
PubMed1994

Molecular defects in CRM+ factor VII deficiencies: modelling of missense mutations in the catalytic domain of FVII.

The molecular defects causing CRM+ factor VII deficiency were investigated in seven unrelated subjects and several members of their families. Four missense mutations located in the catalytic domain of factor VII were found. The previously reported 304Arg-->Gln substitution was present in the homozygous and heterozygous forms, with different polymorphic haplotypes, thus demonstrating that it is recurrent and frequent in the Italian population. The 310Cys-->Phe substitution was found in the homozygous form and in the compound heterozygous condition with the nonsense mutation 356Trp-->stop. Two missense mutations, 298Met-->Ile and 342Gly-->Arg, were found in the homozygous and in the heterozygous condition respectively. Molecular heterogeneity was further increased by finding of the 353Arg-->Gln polymorphism in the doubly heterozygous condition with the 304 and 342 mutations. Plausible explanations for loss of FVII function were found by inspecting a model of the serine protease domain of factor VIIa. Inefficient activation of the catalytic site is predicted for 298Met-->Ile. 342Gly-->Arg would directly distort the geometry of the 'oxyanion hole' preventing formation of a substrate enzyme intermediate. 310Cys-->Phe is predicted to have an adverse effect on tissue factor interaction. These mutations point to important regions of the factor VII molecule.

Antigens↗
PubMed1994

Combined surgery and chemotherapy in primary gastric non-Hodgkin's lymphoma: a retrospective study in sixty-six patients.

Sixty-six consecutive patients with primary gastric non-Hodgkin's lymphoma are reported. All patients underwent surgery which consisted of radical resection in 23 patients (36%) and partial or palliative excision in the remaining 43 cases (36 and 7 respectively). Three patients died before starting chemotherapy, two refused the treatment and 61 completed the postoperative chemotherapeutic programme. We analysed this group of patients in order to assess the efficacy of chemotherapy following surgery. Chemotherapy included either CVP or the original protocols from our institution. Excluding patients who underwent radical resection, postoperative chemotherapy induced complete remission in 87% of the remaining 39 patients. After a median follow-up of 84 months (range 6-216), the 10-year cause-specific survival was 90% with a stable curve plateau after about 25 months. The survival was only influenced by response to therapy (p < 0.0001). The disease-free survival for patients who were not radically resected was 93%. We encountered only two relapses after 15 and 32 months. One of these was local and the other systemic. Our results indicate that chemotherapy following surgery induces long-term remission and survival in primary gastric lymphoma and in particular improves remission and survival, in stage II. In our opinion, surgery may also be fundamental for the treatment of gastric lymphoma in the majority of cases.

Adolescent↗
PubMed1993

Resistance to activated protein C in nine thrombophilic families: interference in a protein S functional assay.

Nine thrombophilic patients who had had previous diagnoses of functional protein S deficiency were reinvestigated. The functional protein S assays gave dose-response curves that were not parallel to those of the reference plasma. The same pattern was true for approximately half of the first-degree relatives of the propositi. When protein S was extracted from the plasma of the patients by immunoabsorption, it had a normal ratio of functional activity to immunologic concentration. Restriction fragment length polymorphism analysis, informative in one family, showed no linkage between the protein S gene marker and the abnormal behavior of the protein S functional assay. All the propositi and 23/36 first-degree relatives were resistant to the prolongation of activated partial thromboplastin time induced by activated protein C. Furthermore, there was striking concordance in all patients and relatives between the abnormal pattern of the protein S functional assay and resistance to activated protein C. We conclude that a plasma-based functional protein S assay is sensitive to activated protein C resistance and this may lead to spuriously low results in the assay. In agreement with the results of others, this study indicates that resistance to activated protein C is a frequent hemostatic defect in selected thrombophilic populations.

Base Sequence↗