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T Mandalaki

Publications and source records attributed to T Mandalaki.

At least 19 recordsLinked to original sources
PubMed2005

HLA antigens as predictors of disease progression in HIV-infected haemophilia patients (a 22 years' follow up).

Our objective was to assess the influence of genetic factors such as HLA classes I and II antigens and other clinical and laboratory variables on the progression of HIV disease in a cohort of 118 HIV infected haemophilic subjects of Greek origin who had been typed for HLA antigens and were followed up prospectively for 22 years since seroconversion. At the end of the follow up we compared two groups of patients: 22 patients who had a fast progression to AIDS (median 6 years since seroconversion) vs. 33 patients who remained asymptomatic in stage A2 for up to 22 years (median 15 years). The results showed that the two groups did not differ significantly in age at seroconversion or baseline CD4+ T cell count. However there was a difference in the frequencies of certain HLA antigens in the two groups. The fast progressors had a higher frequency of HLA-A28, B21 and DR3, which was statistically significant (P = 0.02, 0.04, 0.05, respectively) compared to the slow progressors. These findings based on classical HLA typing techniques confirm other published observations and support the effect of genetic background in the progression of HIV infection in haemophilics.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Effect of recent thymic emigrants on progression of HIV-1 disease.

BACKGROUND: The concentration of T-cell receptor-rearrangement excision DNA circles (TREC) in peripheral-blood T cells is a marker of recent thymic emigrant alphabeta T cells. We studied the predictive ability of measurements of TREC for clinical outcome in HIV-1-infected individuals. METHODS: We measured TREC in peripheral-blood mononuclear cells with a real-time PCR assay. We studied 131 Greek participants in the Multicenter Hemophilia Cohort Study who had known HIV-1 seroconversion dates. The prognostic value of baseline TREC, CD4 T-cell count, and HIV-1 RNA concentration was assessed by Kaplan-Meier and Cox's regression analysis. FINDINGS: Four participants had progressed to AIDS by first blood sampling. Among the remaining 127 individuals, the median value of TREC per 10(6) cells was 6900 (IQR 2370-15604). Baseline TREC values were lower in the 53 who progressed to AIDS than in those who did not (geometric mean 2843 [95% CI 1468-5504] vs 6560 [4723-9113] per 10(6) cells; p=0.017). The relative hazard of AIDS, adjusted for plasma viral load, CD4 T-cell count, and age at seroconversion was 1.44 (95% CI 1.04-2.01; p=0.031) per ten-fold increase in TREC; that for death was 1.52 (1.12-2.06; p=0.007). The adjusted relative hazards of death were 2.91 (1.91-4.44; p<0.001) per ten-fold increase in plasma HIV-1 RNA load and 1.20 (1.04-1.38; p=0.014) per 100-cell decrease in CD4 T-cell count. INTERPRETATION: The concentration of TREC in the peripheral T-cell pool complements HIV-1 RNA load and CD4 T-cell count in predicting the rate of HIV-1 disease progression. Recent thymic emigrants have a role in the pathogenesis of HIV-1 disease.

Adult↗
PubMed2000

Resistance to activated protein C and FV leiden mutation in patients with a history of acute myocardial infarction or primary hypertension.

This study was designed to investigate both resistance to activated protein C (APC-R) and the factor FV Q506 mutation incidence in patients with a history of acute myocardial infarction (AMI) and patients with primary hypertension (PH), a high-risk group for arterial thrombosis. Eighty patients with a history of AMI (group A), 160 patients with a history of PH (group B), and 124 age-matched controls without arterial disease (group C) were studied. APC-R was determined using the Coatest APC Resistance Kit of Chromagenix, Sweden. The prevalence of the FV Q506 mutation was estimated by DNA analysis (Bertina method). The prevalence of the FV Q506 mutation was 20%, 13.75%, and 8% in groups A, B, and C, respectively (A v C P = .0466). The prevalence of APC-R was 47.5% in group A v 13% in group C (P < .0001) and 36.25% in group B v 13% in group C (P < .0001). The response to activated protein C expressed as mean value +/- SD was 2.05 +/- 0.33 in group A v 2.56 +/- 0.46 in group C (P < .05) and 2 +/- 0.22 in group B v 2.56 +/- 0.46 in group C (P < .05). These findings suggest that patients with a history of AMI or PH have a significantly increased incidence of both APC-R and FV Q506 mutation compared with the control group. These findings support the hypothesis that these anticoagulant defects may be risk factors for arterial thrombosis.

Activated Protein C Resistance↗
PubMed1999

Effects of glibenclamide on postprandial coagulation activation.

BACKGROUND AND AIM: Previous data indicate that even mild postprandial hyperglycaemia in diabetic subjects, who are concerned to be in good control, activates haemostasis. The aim of this study was to investigate the effect of the oral administration of 5 mg glibenclamide on postprandial activation of coagulation in type 2 diabetics. METHODS AND RESULTS: We designed a placebo controlled, randomised study. After an overnight fast, each subject (n = 16, age 50-68 yr.) underwent a standard test meal (600 Kcal: carbohydrates 40%, lipids 50%, proteins 10%) preceded by one tablet of glibenclamide (5 mg) or placebo. The two tests were performed randomly, with an interval of 7 days. Blood samples were collected at baseline and 2 and 4 hours after the meal to measure the concentrations of glucose, insulin, c-peptide, triglycerides as well as of d-dimers, fibrinogen, F1.2 and TAT. The postprandial levels of TAT, fibrinogen, F1.2, d-dimers, insulin, glucose and triglycerides were significantly higher compared to baseline values. CONCLUSIONS: The postprandial levels of glucose, triglycerides, fibrinogen, F1.2, TAT and d-dimers were lower after glibenclamide administration as compared to placebo, while the concentrations of insulin and c-peptide were higher. Thus, acute administration of glibenclamide reduces the postprandial activation of coagulation.

Administration, Oral↗
PubMed1998

Determinants of progression of HIV infection in a Greek hemophilia cohort followed for up to 16 years after seroconversion.

Our objectives are to describe the progression of HIV disease and to assess the influence of hemophilia-related variables, age at infection, and antibodies to cytomegalovirus infection (anti-CMV) in a Greek cohort of 158 HIV-1-positive hemophilic men, who received prospective follow-up for up to 16 years after infection. A total of 79 patients had died, representing a cumulative progression rate of 72.4% (95% confidence interval [CI], 56.6-83.3). A significant proportion of the mortality (30%) resulted from conditions not formally related to AIDS, with liver failure and cerebral hemorrhage predominant. At 16 years after seroconversion, 66 patients had developed clinical AIDS, a cumulative progression rate of 58.2% (95% CI, 47.1%-86.3%) whereas 15 years after infection 81.5% (95% CI, 74.2%-87.9%) of the patients had AIDS or a CD4 cell count <200 cells/mm3. Hemophilia-related variables or presence of anti-CMV were not significantly associated with disease progression. Age at infection was a strong prognostic factor for all three endpoints. Appropriate modeling showed a nonlinear age effect, with a steeper increase of relative hazard for patients >40 years of age at seroconversion. The age effect remained significant even after controlling for current CD4 cell count. Further investigation is required to elucidate the mechanisms of the age effect and the contribution of HCV coinfection on the disease progression.

Adolescent↗
PubMed1998

A novel insertion mutation (1286insC) in exon 9 of the factor XIII-A subunit gene.

Molecular studies have been performed on a Greek family with factor XIII-A subunit deficiency. The 15 exons of the A subunit gene were amplified by polymerase chain reaction and analysed by direct nucleotide sequencing. A homozygous single base insertion (1286insC) in exon 9 of the gene was identified in three affected family members. The insertion results in a frameshift and a premature stop signal a short distance downstream at codon 403. Any A subunit protein expressed is likely to be unstable and lack part of the catalytic core domain together with both beta barrel domains towards the C-terminal of the molecule. This study contributes to our knowledge of the mutational spectrum in patients with factor XIII-A deficiency.

DNA Transposable Elements↗
PubMed1997

Haemostasis balance disorders in patients with essential hypertension.

This study was aimed at investigating haemostasis parameters in patients (pts) with arterial hypertension (AH) before any medical treatment and to correlate these findings with those in healthy normal Greek population 83 pts (48 m, 35 w) mean age 49.8 +/- 10.1 yrs, body mass index 23.4 +/- 1.5 with mild to moderate AH and 42 healthy volunteers matched for sex (24 m, 18 w), age 51.2 +/- 10.5 yrs and body mass index 22.8 +/- 1.46 were studied. Fibrinogen, vWF, plasminogen, ECLT, a2 antiplasmin, tPA-Ag, PAI-1 in all pts and in the control group were measured. Mean age and BMI did not significantly differ between the two groups. The hypertensive patients had significantly higher levels of fibrinogen (327.75 +/- 51.36 vs. 272.84 +/- 46.8 mg/dl), tPA-Ag (8.81 +/- 3.32 vs. 5.76 +/- 2.54 ng/ml) and PAI-1 (11.8 +/- 10.9 vs. 7.91 +/- 5.5 IU/ml), whereas a2 antiplasmin level was significantly lower (98.71 +/- 15.40 vs. 107.84 +/- 17.52%). No differences were found between hypertensives and normal subjects in vWF, plasminogen and ECLT. These preliminary data suggest that in pts with mild to moderate AH, before any medical treatment, there are significantly higher levels of fibrinogen, tPA-Ag and PAI-1 compared with normal volunteers, whereas there are significantly lower a antiplasmin levels. These findings indicate a disturbance in the haemostasis balance with hypercoagulability and fibrinolytic deficiency.

Adult↗
PubMed1997

Parvovirus B19 quiescence during the course of human immunodeficiency virus infection in persons with hemophilia.

To detect and characterize parvovirus B19 infection during the course of progressive immune deficiency from human immunodeficiency virus (HIV), ten subjects enrolled in the Multicenter Hemophilia Cohort Study were followed for 6.4 to 15 years from HIV seroconversion through extreme immune deficiency. Four to five sera or plasma samples from each subject, collected at predetermined CD4+ lymphocyte levels, were tested for immunoglobulin G (IgG) and M (IgM) B19 antibodies and DNA. All 42 samples were positive for B19 IgG antibodies, and three were weakly positive for IgM antibodies. Only one sample, collected coincident with HIV seroconversion, was unequivocally positive for B19 DNA. No persistent hematologic adverse effects of B19 infection were observed. Thus, although B19 IgG antibodies are highly prevalent among HIV-infected persons with hemophilia or related disorders, B19 viremia and its hematologic consequences were not detected, even with severe depletion of CD4+ lymphocytes. If primary B19 infection occurs after immune deficiency, however, the consequences may be more adverse.

Adolescent↗
PubMed1996

Factor XIII(A) subunit deficiency due to a homozygous 13-base pair deletion in exon 3 of the A subunit gene.

We investigated the molecular basis of factor XIII(A) subunit deficiency in a Greek family. Each of the 15 exons of the A subunit gene were individually amplified by polymerase chain reaction, using previously reported oligoprimers. The proband with severe deficiency was found to have a homozygous 13-base pair deletion in the 3' half of exon 3. The deleted sequence, extending from codons 82-86, results in a frameshift and generates a downstream termination codon in exon 4. Single strand conformation polymorphism (SSCP) analysis detected no additional mutations in the coding or consensus splice sequences of the A subunit gene. Both parents of the proband were heterozygous for the defect. Only one previous microdeletion (AG dinucleotide) has been reported in the A subunit gene, and was located at the intron B-exon 3 boundary. Further studies are necessary to determine whether this region of the gene is a "hot spot" for microdeletion mutations.

Amino Acid Sequence↗
PubMed1995

Factor VIII gene inversions in severe hemophilia A: results of an international consortium study.

Twenty-two molecular diagnostic laboratories from 14 countries participated in a consortium study to estimate the impact of Factor VIII gene inversions in severe hemophilia A. A total of 2,093 patients with severe hemophilia A were studied; of those, 740 (35%) had a type 1 (distal) factor VIII inversion, and 140 (7%) showed a type 2 (proximal) inversion. In 25 cases, the molecular analysis showed additional abnormal or polymorphic patterns. Ninety-eight percent of 532 mothers of patients with inversions were carriers of the abnormal factor VIII gene; when only mothers of nonfamilial cases were studied, 9 de novo inversions in maternal germ cells were observed among 225 cases (approximately 1 de novo maternal origin of the inversion in 25 mothers of sporadic cases). When the maternal grandparental origin was examined, the inversions occurred de novo in male germ cells in 69 cases and female germ cells in 1 case. The presence of factor VIII inversions is not a major predisposing factor for the development of factor VIII inhibitors; however, slightly more patients with severe hemophilia A and factor VIII inversions develop inhibitors (130 of 642 [20%]) than patients with severe hemophilia A without inversions (131 of 821 [16%]).

Blotting, Southern↗
PubMed1995

Family studies in an extremely large mild haemophilia A pedigree which includes 10% of Greek haemophiliacs.

We illustrate the usefulness of direct mutation detection for genetic counseling by showing its application to an extremely large mild haemophilia A pedigree (91 haemophiliacs) originating from the village of Aiani in Macedonia, northern Greece. The causative mutation has already been shown to be an A to T transversion in codon 280 of the FVIII gene which replaces Asn 280 (AAC) by Ile (ATC) and which creates a new Bam HI restriction site in exon 7. The latter permitted direct, rapid and reliable detection of the mutation in relevant family members. All major branches of the family were shown to share the mutation, and carrier status was diagnosed or excluded for 23 possible carriers. Other interesting characteristics of the Aiani haemophilic population are a slightly higher longevity and fecundity than that observed in the general population and a wide range of FVIII:C levels (5-25%) associated with the mutation.

Base Sequence↗
PubMed1994

Epidemiology of haemophilia in Greece: an overview.

Demographic data of the Greek haemophilia A and B population for the period 1972-1993 were analyzed. Prevalence at birth including known not-registered patients was calculated at 23.1 per 100,000 male births. However, the observed prevalence in 1993 was only 61% of the expected. Since 1975 the proportion of mild cases had significantly increased. Adjusted by age, severity and HIV status reproductive fitness of haemophiliacs was 0.62. Overall mortality was 2.6 times higher than in the general population, but 7.9 times among patients with severe haemophilia and 16.4 among HIV(+) haemophiliacs. Fifty out of 78 deaths occurred among HIV(+) patients and 28 of these were caused by AIDS. Inhibitor patients did not show excess mortality due to bleeding. Cancer mortality was equal to normal, but the number of deaths from ischaemic heart disease was 0.25 of the expected. Risk of death due to cerebral haemorrhage was 3.8 times higher in HIV(+) haemophiliacs than in HIV(-).

Adolescent↗
PubMed1993

Association between HLA antigens and progression of HIV infection in Greek haemophiliacs.

The frequencies of HLA antigens in 33 HIV seronegative and in 88 HIV seropositive haemophiliacs, who have been followed for at least 6 years since seroconversion or first HIV positive test, were evaluated in relation to disease susceptibility and disease progression. A high frequency of HLA-A2 and -DR2 antigens and a low frequency of HLA-A9 were found to characterize HIV seropositive patients (p < 0.05). Progressors to symptomatic CDC stage IV had a higher frequency of HLA-A9 (p < 0.01) and DR3. Rapid decline of CD4+ T cells in these patients was associated with HLA-A9, -DR1 and DR3. Our data suggest that HLA antigens may contribute to susceptibility to HIV infection and disease progression in Greek haemophiliacs.

Adolescent↗