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D Alavantić

Publications and source records attributed to D Alavantić.

13 recordsLinked to original sources

Angiotensin I-converting enzyme gene polymorphism in a Serbian population: a gender-specific association with hypertension.

Human essential hypertension has a multifactorial origin and is caused by a delicate interaction between susceptibility genes and environmental factors. Candidate genes are selected from the renin-angiotensin system (RAS) and are physiologically implicated in blood pressure regulation. We investigated the association between insertion/deletion (I/D) polymorphism at the angiotensin-converting enzyme (ACE) locus and hypertension in a case-control study conducted in a population of Caucasians (175 females, 210 males). Case subjects were those with untreated borderline hypertension. A significant, moderate, male, gender-specific independent association between DD genotype and high blood pressure was found. Adjusted odds ratio (OR) was 2.0 (95% CI, 1.1 to 3.9; p=0.03) in the whole group and 2.5 (95% CI, 1.2 to 5.1; p=0.01) in the group truncated on the basis of age (< or = 50 years). Our findings support the hypothesis that ACE is a gender-specific candidate gene for hypertension.

Adult↗

APO B 3' HVR polymorphism in healthy population: relationships to serum lipid levels.

We have analyzed allele frequency distribution at the hypervariable locus 3' to the apolipoprotein B gene in a healthy population sample (241 women and 246 men) from the Belgrade area. The bimodal distribution of sixteen different hypervariable region (HVR) alleles and the heterozygosity index (average 0.76) in both samples are similar to ones reported for other Caucasian populations. However, we found the hypervariable element containing 34 repeats-HVE34 allele to be the most common one in both female and male samples, and that there was a lower frequency of the HVE>36 alleles. For further analysis of 3'HVR allele frequency and its possible association with serum lipid levels, all HVR alleles were grouped into five main types (HVE<32, HVE32, HVE34, HVE36, and HVE>36), and the samples were divided into lipid quartiles. We found that (1) apo B gene 3'HVR polymorphism is associated with variation of normal lipid levels in males, (2) HVE32 alleles are associated with decreased serum levels of total cholesterol, LDL cholesterol, and triglycerides, and (3) HVR genotypes containing HVE34 and HVE36 alleles are associated with elevated serum levels of total cholesterol, low density lipoprotein (LDL) cholesterol, and triglycerides.

Adult↗

Hepatitis C virus RNA testing by nested PCR in blood preparations in Yugoslavia.

Patients receiving any kind of human blood preparations are in permanent danger of any infection including hepatitis C (HCV) infection. Testing for the presence of HCV in blood preparations is one of the steps towards safe medical treatment. One of the approaches for this testing is a detection of HCV nucleic acid. In this paper we describe a simple method for isolation of HCV RNA from blood preparations and control of HCV RNA presence in 19 intravenous and intramuscular products, manufactured in the National Blood Transfusion Institute in Belgrade. RT-PCR was performed according the rules saving RNA. Primers were located in 5' conserved region. Seven out of 19 batches of gamma-globulin, albumin, anti-tetanus and anti-rabies immunoglobulin preparations were found to be HCV RNA positive. For the time being, the PCR method is too expensive for routine HCV RNA testing of hundreds of blood donors per day. Serological screening test of blood donors and nested PCR testing for HCV RNA in blood preparations could be an efficient combination of tests in prevention of posttransfusion hepatitis C.

Blood Donors↗

Study of apoB gene signal peptide insertion/deletion polymorphism in a healthy Serbian population: no association with serum lipid levels.

The apolipoprotein B (apoB) signal peptide polymorphism was studied in unrelated healthy individuals. A total of 232 women and 222 men were analyzed separately. The relative frequencies of Del allele in women and men were 0.42 and 0.37, respectively. More heterozygous individuals were detected in comparison with other populations, using a modified silver staining method on polyacrylamide gel for visualization of Ins and Del alleles. There was no statistically significant difference in mean lipid levels adjusted for age, BMI, smoking habit and blood pressure between the three Ins/Del genotypes in both samples (ANOVA). Therefore, no differences were shown in the genotype frequency distribution throughout the lipid quartiles.

Adult↗

Apolipoprotein B gene DNA polymorphisms (EcoRI and MspI) and serum lipid levels in the Serbian healthy population: interaction of rare alleles and smoking and cholesterol levels.

The frequency of restriction fragment length polymorphisms (RFLPs) of the apolipoprotein B (apo B) gene, detected by EcoRI and MspI, and their influence on serum lipids were studied in a total of 239 healthy subjects from the Belgrade area. The influence of interaction between different genotypes and smoking was also studied. The relative frequency of both rare R2 and M2 alleles (lacking the cutting site) was similar to that reported in other groups of Caucasians (0.16 and 0.11, respectively). No association was observed between the apo B genotypes and serum lipid levels adjusted for age, body mass index, and blood pressure either in the whole sample or in either women or men. When smokers and non-smokers were considered separately, smoking had a significant impact on total cholesterol variability in all individuals with genotype M1M2 and high density lipoprotein (HDL) cholesterol variability in women with genotype R1R2. The presence of the rare alleles of these two polymorphisms in smokers was associated with lower lipid levels in the whole sample and in both women and men analyzed separately, except for an increase of HDL cholesterol level in male smokers, heterozygous for EcoRI polymorphism (R1R2).

Adult↗

In vivo genotoxicity of nitrates and nitrites in germ cells of male mice. I. Evidence for gonadal exposure and lack of heritable effects.

Effects of nitrate (doses of 600 and 1200 mg/kg/day during 14 days) and sodium nitrite (60 and 120 mg/kg/day during 14 days) on germ cells of male mice were investigated. The mode of application was stomach intubation. The germ cell stages analysed were spermatids (for the heritable effects) and differentiating and stem-cell spermatogonia (for direct effects). A lack of heritable translocations, sperm abnormalities, as well as morphological changes, such as changes in eyes, coat colour, testes and body weight, was demonstrated in F1 males originating from treated P males. Significant effects in treated males were found with respect to: (1) sex-chromosomal univalency in the diakinesis-methaphase I stage after the treatment of stem spermatogonia (both doses of sodium nitrate and the higher dose of sodium nitrite), (2) sperm-head abnormalities after treatment of differentiating spermatogonia (the higher dose of sodium nitrate and both doses of sodium nitrite), and (3) fertility after treatment of spermatids (the higher dose of sodium nitrite). Nonmutagenic effects and possible carcinogenic potential of the tested doses are discussed.

Animals↗

In vivo genotoxicity of nitrates and nitrites in germ cells of male mice. II. Unscheduled DNA synthesis and sperm abnormality after treatment of spermatids.

Effects of both sodium nitrate (doses of 600 and 1200 mg/kg/day for 3 days) and sodium nitrite (doses of 60 and 120 mg/kg/day for 3 days) on spermatids of mice were investigated by measuring unscheduled DNA synthesis (UDS) 17 days after the end of treatment, and sperm-head abnormality 11 and 17 days after the end of treatment. Neither chemical induced the UDS response in early to mid spermatids (17 days). The only positive result in the sperm-head abnormality test was obtained for the dose of 120 mg/kg/day of sodium nitrite both at 11 and 17 days after treatment. The results presented are in accordance with those of our earlier experiments with the same chemicals, suggesting their nonmutagenic action on the tested germ-cell stages of male mice.

Animals↗

Effect of saccharin on the induction of chromosomal translocations in male mice and their F1 offspring.

The dose-dependent effects of sodium saccharin on the fertility and the induction of chromosomal translocations in treated mice and their F1 males were examined. C3H X 101 mice were treated with saccharin for 2 successive weeks at doses of 200 and 500 mg/kg of body wt. Data from the fertility study showed that saccharin did not induce any significant effect on fertility. Cytological analysis of meiotic cells showed no chromosomal rearrangements. Semisterility and sterility were noted in F1 males of saccharin-treated animals. In semi-sterile and sterile F1 males of saccharin-treated animals chromosomal translocations were not found.

Animals↗

Meiotic chromosomal translocations in male induced by X-irradiation.

The dose-response curve for reciprocal translocations induced by acute exposure of spermatogonial stem cells to X-rays in treated mice and their F-1 sons was examined. Male mice were totally irradiated with doses of 1 Gy; 5 X 1 Gy and 5 Gy. The obtained results show that frequency of the chromosomal translocations in directly treated animals is dose dependent. The percentage of animals irradiated with 1 Gy which had the chromosomal translocations was 60, while this percentage in animals irradiated with single and fractionated dose of 5 Gy was 100. The frequency of chromosomal translocations varies from 1.5% to 8.0%. Multivalent configurations in F-1 males were observed after exposure to 5 Gy only. The incidence of F-1 translocated males was 17.5%.

Animals↗

Effects of post-irradiation interval on translocation frequency in male mice.

Hybrid male mice were given 5 Gy + 5 Gy acute X-rays 24 h apart, with cytological examination of testes 16-19, 39-42 and 64-66 weeks later. Mean testis weights were significantly lower in the youngest group than in the other two. However, translocation frequencies in spermatocytes of the youngest group (mean of 0.57 per cell) were significantly higher than in either of the other two groups, which gave similar values averaging 0.36 translocations per cell. There was highly significant heterogeneity in translocation yields within the youngest group. The decline in translocation yield with time after irradiation is in line with that reported by Léonard and Deknudt (1970) in inbred strain C57BL males. Analysis of all available data suggests that high translocation yields are found during late stages in the process of germ-cell repopulation of the testis after high radiation doses and may be connected with changing frequencies of radiosensitive and radioresistant stem cell populations as repopulation proceeds.

Animals↗

[Detection of the presence of the hepatitis C viral genome in immunoglobulin preparations using RT-PCR].

Contemporary methods of molecular genetics were used to investigate the presence of hereditary matter, i.e., virus hepatitis C genome in immunoglobulin preparations of the Institute for blood transfusion of the Republic of Serbia. ELISA test in immunoglobulin preparations indicated the presence of antibodies to an antigen of hepatitis C virus. After RNA isolation and reverse transcription (RT), double reaction of in vitro DNA amplification (PCR) was done using two pairs of oligonucleotide. After several repeated tests and positive control from blood of the diseased it was concluded that neither of 11 investigated immunoglobulin preparations contained the nucleic acid (RNA) of the HCV origin, that meant that all preparations could be used with no danger of virus hepatitis C infection. Regarding the current experience in relation to the use of PCR for testing of contamination by hepatitis C virus in preparations from human blood, that are used in the therapy of various conditions and diseases, it is recommendable to use this method due to its sensitivity and specificity.

DNA, Viral↗

Genetic variation at the apoB 3'hypervariable region in a Serbian population.

We investigated common length polymorphism caused by a variable number of tandem repeats in the hypervariable region located at the 3' end of the human apolipoprotein B gene in 696 Serbian (Belgrade area) unrelated individuals of both genders. After using the polymerase chain reaction to amplify this polymorphic region, 17 different alleles, containing 22-54 repeats, were distinguished. The bimodal distribution and the heterozygosity index (average 0.71) obtained in both genders are similar to those reported for other Caucasian populations. However, the HVE34 allele was found to be the commonest in both female and male samples. There was also a lower frequency of the HVE > 36 alleles than in other Caucasian populations studied.

Apolipoproteins B↗