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I Matei

Publications and source records attributed to I Matei.

At least 19 recordsLinked to original sources
PubMed2001

Somatic frameshift mutations in the Bloom syndrome BLM gene are frequent in sporadic gastric carcinomas with microsatellite mutator phenotype.

BACKGROUND: Genomic instability has been reported at microsatellite tracts in few coding sequences. We have shown that the Bloom syndrome BLM gene may be a target of microsatelliteinstability (MSI) in a short poly-adenine repeat located in its coding region. To further characterize the involvement of BLM in tumorigenesis, we have investigated mutations in nine genes containing coding microsatellites in microsatellite mutator phenotype (MMP) positive and negative gastric carcinomas (GCs). METHODS: We analyzed 50 gastric carcinomas (GCs) for mutations in the BLM poly(A) tract aswell as in the coding microsatellites of the TGFbeta1-RII, IGFIIR, hMSH3, hMSH6, BAX, WRN, RECQL and CBL genes. RESULTS: BLM mutations were found in 27% of MMP+ GCs (4/15 cases) but not in any of the MMP negative GCs (0/35 cases). The frequency of mutations in the other eight coding regions microsatellite was the following: TGFbeta1-RII (60 %), BAX (27%), hMSH6 (20%),hMSH3 (13%), CBL (13%), IGFIIR (7%), RECQL (0%) and WRN (0%). Mutations in BLM appear to be more frequently associated with frameshifts in BAX and in hMSH6and/or hMSH3. Tumors with BLM alterations present a higher frequency of unstable mono- and trinucleotide repeats located in coding regions as compared with mutator phenotype tumors without BLM frameshifts. CONCLUSIONS: BLM frameshifts are frequent alterations in GCs specifically associated with MMP+tumors. We suggest that BLM loss of function by MSI may increase the genetic instability of a pre-existent unstable genotype in gastric tumors.

Adenosine Triphosphatases↗
PubMed1999

p56lck activity and expression in peripheral blood lymphocytes from patients with systemic lupus erythematosus.

In this study we analyzed the activity and the expression of p56lck protein tyrosine kinase in peripheral blood lymphocytes (PBLs) from systemic lupus erythematosus (SLE) patients and from healthy donors. The p56lck activity, determined by a non-radioactive Tyrosine Kinase Assay Kit, was significantly higher in active SLE PBLs and discriminated this group of patients from inactive SLE patients (p = 0.002) and healthy donors (p = 0.009). p56lck level decreased in SLE lymphocytes (especially for inactive SLE lymphocytes, p = 0.005) when compared to healthy donors. These differences were also reflected by the specific activity of p56lck that was clearly elevated in active SLE lymphocytes when compared to inactive SLE (p = 0.022) or healthy donors lymphocytes (p = 0.006). A positive correlation between the activity of p56lck and the tyrosine phosphorylation level in active SLE lymphocytes was found.

Animals↗
PubMed1996

Tyrosine phosphorylation in peripheral lymphocytes from patients with systemic lupus erythematosus.

A comparative study of tyrosine phosphorylation was performed on peripheral blood lymphocytes from systemic lupus erythematosus (SLE) patients and from healthy donors. Freshly isolated SLE lymphocytes presented an elevated tyrosine phosphorylation level when compared to healthy donors lymphocytes (p = 0.005). Among all phosphorylated proteins, those called p120, p110, p80 and p55-p60 were more phosphorylated. The level of tyrosine phosphorylation of p120 and p110 proteins discriminated significantly (p = 0.0048, respectively, p = 0.02) between SLE patients and healthy donors. Lymphocytes form SLE patients and healthy donors were then stimulated by cross-linking T cell antigens (CD3, CD4, CD8) to further distinguish the signal transduction between normal and pathologic lymphocytes. No statistical differences in the tyrosine phosphorylation pattern, following CD4 or CD8 cross-linking, were observed between SLE patients and healthy donors lymphocytes. CD3 cross-linking induced an effect on tyrosine phosphorylation different in SLE patients versus healthy donors lymphocytes. Thus, the lymphocytes of SLE patients were refractile in anti-CD3 stimulation in comparison with the healthy donors lymphocytes. Chi-square analysis demonstrated that a significantly larger number of healthy donors responded to anti-CD3 stimulation compared to SLE patients (p = 0.03). The high frequency of tyrosine phosphorylation of p110 and p80 proteins, following CD3 stimulation, in normal versus SLE lymphocytes, suggested that these proteins could be involved in abnormal signal transduction in SLE cells.

CD3 Complex↗
PubMedDate not supplied

Treatment with alpha-interferon in chronic hepatitis.

The treatment of chronic viral hepatitis with Interferon has been introduced in clinical practice over the past decade an represents an important step in the management of those diseases. The data existing in literature are conflicting about the dose and period of treatment with Interferon, many treatment schedules being proposed. There are also a lot of markers used or proposed to be used to determine the response to treatment, their predicting efficacy being largely studied. The response to alpha-Interferon in a standard 6 month regimen in chronic hepatitis B, chronic hepatitis C and chronic hepatitis B and C is studied; alanine-aminotransferase (ALAT) and aspartate-aminotransferase (ASAT) are the markers used to determine the response to treatment.

Adolescent↗
PubMedDate not supplied

Correlation of serum interferon with some clinical and humoral signs of systemic lupus erythematosus.

The serum level of total interferon (IFN) was measured in 15 male patients with systemic lupus erythematosus (SLE) in the active phase and in remission, before and during corticotherapy. The values found were correlated with the clinical and humoral signs of disease. The IFN titer was high in the active phase of disease and was correlated with fever, extension of skin rash, polyarthritis, myositis, autoimmune hemolysis, cardiac and cerebral involvement as well as with ESR, reacting protein C, CIC, ANF and the percentage of LE cells. Isolated LE nephropathy without rapidly progressive or advanced renal failure was not associated with high IFN titer.

Adult↗