Studies on angiotensin-converting enzyme insertion/deletion polymorphism and genotype distributions in Turkish preeclampsia patients.

Placental, immune and genetic factors are thought to play an important role in preeclampia (PE)'s pathophysiology. Angiotensin-Converting Enzyme (ACE) plays a vital role in the renin-angiotensin-system (RAS) which regulates blood pressure by converting angiotensin I into a powerfull vasoconstrictor angiotensin II. A deletion polymorphism (D allele) has been reported to be associated with elevated ACE activity. The aim of the this study was to investigate whether there is an association between angiotensin converting enzyme (ACE) insertion/deletion (I/D) polymorphism and PE. In this study, 120 preeclamptic and 116 normotensive Turkish pregnant women were genotyped for ACE I/D polymorphism and the distribution of genotype and allele frequencies of this polymorphism in preeclampsia and controls were evaluated. Codominant, dominant and recessive models were appplied in ACE gene I/D polymorphism. In the codominant model, DD genotype was found significantly more frequent in preeclampsia than controls (P = 0.016). Moreover, in dominant model (DD frequency versus DI+II frequency) there was a significant relation between DD genotype and preeclampsia (P = 0.006). D allele frequency was 64.6% in preeclampsia while it was 56.1% in controls (P = 0.062). In conclusion, there was significant difference in genotype distribution between preeclampsia and controls.

The reliability of maternal serum triple test in prenatal diagnosis of fetal chromosomal abnormalities of pregnant Turkish women.

AIM: The purpose of this article was to evaluate the reliability of maternal serum triple marker screening of alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol for the prenatal diagnosis of fetal chromosomal abnormalities in Turkish pregnant women. METHOD: Medical records were used to analyze indications of amniocentesis and quantitative fluorescent-polymerase chain reaction. Anomaly screening was performed for all patients between 13 and 22 weeks of pregnancy. A total of 1725 pregnancies with chromosomal abnormality risk according to triple test screening were accepted for fetal chromosome analysis and quantitative fluorescent-polymerase chain reaction. RESULTS: Chromosomal aberrations were observed in 56 (3.2%) cases. About 44.6% of the abnormalities detected were numerical aberrations; however, 55.3% of the abnormalities were structural aberrations. Abnormalities detected were inversion of chromosome 9 in 20 cases, trisomy 21 in 14 cases, 46,XX/47,XX, +21 in 1 case, trisomy 18 in 2 cases, trisomy 13 in 1 case, 47,XXY, in 1 case, 45,X, in 1 case, structural abnormalities in 12 cases, and mosaic or tetraploidy in 6 cases. CONCLUSION: Second trimester triple test is an effective screening tool for detecting fetal Down syndrome in Turkish women.

Suppression of the tumorigenicity of B-16V melanoma cells via lysozyme gene.

OBJECTIVE: The aim of this study was to evaluate the effects of lysozyme on the tumorigenicity of B-16V melanoma cells. METHODS: After performing a series of molecular biology applications, including mRNA isolation, reverse transcriptase polymerase chain reaction, restriction digestions and ligations, recombinant pHM6 vector harboring mouse lysozyme gene (pHM6mLys) was constructed. B-16V melanoma cells were transfected with plasmid DNAs (pHM6 and pHM6mLys). Transfected cells (B-16VpHM6 and B-16VpHM6mLys) were selected in media containing geneticin. B-16V, B-16VpHM6, and B-16VpHM6mLys cells were then injected subcutaneously (s.c.) to the three groups of C57BL/6 inbred mice (30 mice/group). These mice were examined every 3 days for s.c. tumor development over 41 days. The results were evaluated by using statistical methods. RESULTS: Tumor formation was observed in all mice injected with B-16V and B-16VpHM6 cells in the first 8-12 days. However, tumor didn't develop in 16 of 30 of the mice injected with B-16VpHMmLys cells. Tumor-free animals (16 mice) in this group were reinjected with B-16V cells, and 9 of them died during the first 10 days of observation. Tumor development was not observed in the remaining 7 mice over 60 days of the experimental period. Results were statistically significant (p values < or = 0.05). CONCLUSIONS: These findings indicate that lysozyme expressed by B-16VpHMmLys cells may suppress the tumorigenicity of these cells and may help development of protective immunity against B-16V melanoma cells.

Polymorphisms in the tumor necrosis factor-alpha gene in Turkish women with pre-eclampsia and eclampsia.

The genetic background predisposing pregnant women to pre-eclampsia/eclampsia (PE/E) is still unknown. The aim of the current study was to investigate whether there is an association between the TNF-alpha-308 and 850 polymorphisms and PE or eclampsia. In this study, 40 cases of eclampsia, 113 cases of PE and 80 normotensive control cases were genotyped for the TNF-alpha-G-308A and C-850 polymorphisms. At position 308, the replacement of Guanine with Adenosine was denoted as TNF2. We found a significant difference between the TNF2 allele frequencies of the eclamptic, pre-eclamptic and normotensive controls. TNF2 (AA) polymorphism frequency was significantly higher among the eclamptics and pre-eclamptics (control : 5%, PE : 13.3%, E : 12.9%). A significantly different genotype distribution of C-850T polymorphism was observed between the PE/E and control groups, with the frequency of the variant TT genotype being significantly reduced in the preeclamptics (PE : 17% ; E : 17.5%) when compared with the control group (24.3%). We have demonstrated an association between TNF-alpha polymorphisms and pre-eclampsia susceptibility. However, it is not known whether C-850T polymorphism has a functional effect on the TNF-alpha gene. In addition, it was not possible to determine whether this polymorphism promotes the progression from PE to eclampsia because of no statistically significant difference between eclampsia and the controls.

The importance of arginine mutation for the evolutionary structure and function of phenylalanine hydroxylase gene.

Phenylalanine hydroxylase (PAH) gene mutations were investigated in 23 (46 alleles) unrelated phenylketonuria (PKU) patients in Cukurova region. First, all exons of PAH gene were screened by denaturing high performance liquid chromatography (DHPLC), and then, the suspicious samples were analyzed by direct sequencing technique. Consequently, the following results were obtained: IVS10-11g-->a splicing mutation in 27/46 (58.7%), R261Q mutation in 7/46 (15.2%) and E178G, R243X, R243Q, P281L, Y386C, R408W mutations, each found in the frequency of 2/46 (4.3%). In many countries, Arginine mutations have the highest frequency among PAH gene mutations in PKU patients. Although, CpG dinucleotids are effective in mutations resulting in arginine changes, this finding originated from the studies on the causes of mutations rather than the studies on the importance of arginine amino acid. In our analyses, we have detected that a majority of mutations causing a change in arginine and other amino acids concentrated in exon 7 comprising the catalytic domain (residues 143-410) of PAH gene. Several studies has emphasized the role of arginine amino acid; with the following outcomes; arginine repetition is significant for RNA binding proteins, and for histon proteins in eukaryotic gene expression, and also arginine repetition occurring in the structure of signal recognition particle's (SRPs) as a consequence of post-translational processes is very important in terms of gene expression. Therefore, the role of arginine amino acid in PAH gene is rather remarkable in that it shows the role of amino acids in the protein/RNA interaction that has started in the evolutionary process and is still preserved and maintained in the motif formation of active domain structure due to its strong binding properties. Thus, such properties imply that both arginine amino acid and exon 7 is of great significance with regards to the structure and function of the PheOH enzyme.

The sister-chromatid exchange and acetylcholine esterase enzyme levels among patients with insecticide intoxication in the Cukurova region, Turkey.

This study included 45 patients with intentional insecticide intoxication and 21 with accidental intoxication who were treated at the First-Aid and Emergency Department of Balcali Hospital at the Faculty of Medicine in the Cukurova University, Adana, Turkey, while the control group consisted of 25 people selected from university personnel known to be healthy. Patients with a history of X-ray exposure in the last 6 months or of any virus disease as well as continuous drug users and smokers were excluded, leaving a total of 49 patients. Acetylcholine esterase (Pseudocholinesterase) enzyme (AchE), sister-chromatid exchanges (SCE), the mitotic index (MI), and the replication index (RI) were evaluated. Blood samples were cultured for SCE evaluation and sera separated for AchE levels. Insecticide exposure was generally intentional for suicide in adolescents and at older ages, but accidental for children. AchE levels were found to be significantly lower in organophosphorus (OP) and carbamated (CB) insecticide poisoning groups in comparison with the control group (p<0.001), while the pyrethroid (PY) group was not statistically different for the AchE effect (p>0.05). SCE was found to be significantly higher in OP and CB groups (p<0.001), while the PY and control groups were statistically similar for SCE levels (p>0.05). This study showed an increase in SCE in response to orally ingested insecticides. These findings indicate that insecticide exposure results in cell abnormalities, with resulting impediments to the division and replication of cells, as suggested by MI decreases and RI increases, while the speed of the division cycles of stimulated cells increases.

Use of enzyme-linked immunosorbent assay for detection of natural leishmania infections in phlebotomine sand flies from southeastern Turkey.

In total, 320 phelebotomine sand flies from Alibozlu (Osmaniye), Kizyusuflu (Osmaniye), and Sanliurfa in southeastern Turkey were tested for the detection and identification of Leishmania in vector sand flies by enzyme-linked immunosorbent assay with species-specific monoclonal antibodies. We used monoclonal antibodies that recognize both Leishmania tropica and Leishmania major, and a monoclonal antibody specific only to L. tropica. Phosphate-buffered saline and monoclonal antibody M2 recognizing Leishmania amazonensis were used as controls. Infection rates of sand flies were 0.9% in Alibozlu, 0% Kizyusuflu, and 3.6% in Sanliurfa. Positive sand flies were identified as Phlebotomus sergenti Parrot and Phlebotomus major syriacus Adler & Theodor.

Artificial bloodfeeding of Anopheles sacharovi on a membrane apparatus.

Anopheles sacharovi, the main human malaria vector in Turkey, has been maintained in our laboratory by feeding on anesthetized rabbits for about 20 years but it is a difficult species to colonize and bloodfeed. To eliminate the need for keeping and using live rabbits to supply blood meals, artificial bloodfeeding methods with suitable membrane apparatus were investigated. The feeding apparatus designed by the World Health Organization and 3 other types designed by us (for feeding on preserved human blood) were tested. Artificial membranes (latex and paraffin film) and locally produced and dried calf intestine were used. The calf intestine membrane gave the best feeding results and a modified apparatus designated type III was the most successful. This apparatus was preferable for the artificial feeding of An. sacharovi because it has a small reservoir, is easy to use, is adaptable to different feeding conditions, and supports reasonably high bloodfeeding rates 44.4-50.5% as compared to 35% on live rabbits.

Detection of knockdown resistance mutations in Anopheles sacharovi (Diptera: Culicidae) and genetic distance with Anopheles gambiae (Diptera: Culicidae) using cDNA sequencing of the voltage-gated sodium channel gene.

The knockdown resistance (kdr) mutation in the voltage-gated sodium channel gene (VGSCG), an important resistance mechanism against pyrethroids, was studied in Anopheles sacharovi Favre. It was found that the specific primers Agd1 and Agd2 used for polymerase chain reaction (PCR) amplification of Anopheles gambiae Giles VGSCG also amplified this genomic region in An. sacharovi. Comparison of the IIs4-IIs6 domain segments of the gene indicated 70% nucleotides common to both species and a genetic distance of 0.255 between them. Four different samples of pyrethroid-resistant An. sacharovi produced three types of amino acid, serine (TCG),leucine (TTG),and phenylalanine (TTT) at the kdr mutation point, whereas only two kdr mutations, leucine to phenylalanine and leucine to serine, occur in An. gambiae.