Single umbilical artery and reproduction losses in Slovak population: relation to karyotype and fetal anomalies.

AIM: The purpose of this study was to monitor the association between single umbilical artery (SUA), chromosomal abnormalities and associated anomalies during the routine examination of spontaneous or induced miscarriages and premature births. METHODS: During 1992-2015 we morphologically and cytogenetically examined a series of 4098 samples. For 1330 cases the number of umbilical cord vessels could be reported. RESULTS: The presence of single umbilical artery was identified in 67 fetuses of 1330 pregnancies (5.04 %); 36 of the 67 fetuses (53.7 %) had additional congenital malformations. The cultures were unsuccessful in 29 of 67 cases (43.3 %). 38 cases (56.7 %) were successfully karyotyped; 20 out of them had a normal karyotype and 18 had chromosomal anomalies including trisomy 18 (n = 4), trisomy 13 (n = 3), trisomy 21 (n = 2), trisomy 11 (n = 1), triploidy (n = 3), monosomy X (n = 3) and structural chromosomal aberrations (n = 2). CONCLUSION: Isolated SUA is not at increased risk of chromosomal abnormalities and generally does not endanger pregnancy. All chromosomally abnormal embryos and fetuses had associated congenital anomalies. The most frequently associated congenital anomalies were in the musculoskeletal system, central nervous system and genitourinary tract (Tab. 4, Ref. 44).

Distribution of the most common polymorphisms in TYMS gene in Slavic population of central Europe.

Thymidylate synthetase (TS) plays a critical role in the de novo synthesis of dTMP inside the cell. Therefore, TS is a suitable target for cytotoxic drugs such as fluoropyrimidines. Drug efficacy and toxicity depend on the intracellular level of TS, which is significantly influenced by the polymorphisms in the 5'UTR (TSER - rs45445694, TSER*3G>C - rs2853542) and 3'UTR (1494del TTAAAG - rs151264360) of TYMS gene. Polymorphic variants of TYMS gene affect TS activity via gene expression and transcript stability. Patients who undergo fluoropyrimidine therapy may benefit from genetic testing prior to the administration of chemotherapy. At the 5' terminus of TYMS, there is a polymorphic region represented by a variable number of 28bp long tandem repeats (2-9 tandems) with the G or C nucleotide variant (SNP G>C). The 3'end of TYMS gene may decrease the stability of mRNA in the case of 6 base deletion (1494del6, D). In our study, we have focused on testing of TYMS gene polymorphisms, determination of TYMS variant frequencies in Western Slavic population and comparison of Slovak population with other populations.We performed identification of 5'UTR (rs45445694 - TSER*2 or TSER*3; rs2853542 - TSER*3G>C; TSER*3+ins6) and 3'UTR (rs151264360/1494del6/D) polymorphic regions of TYMS gene among 96 volunteers by PCR-RFLP and fragment analysis. Slovak frequencies of selected polymorphisms were established as follows: the frequency of TSER*2, TSER*3, TSER*3G>C, 1494del6/D and I to be 41%, 59%, 34%, 37.5% and 62.5% respectively. The high resolution of the capillary electrophoresis technique allowed among TSER*3 group identification of a subgroup of four individuals with rare 6bp insertion in 3R allele, id est 2.1% TSER*3+ins6 allele frequency. In our study, we have revealed individuals with rare G>C substitution in the first 28bp tandem repeat of TSER*2 promoter enhancer region (rs183205964) as well, the overall frequency of this polymorphic allele in Slovak population was 2.1%. Our results proved that Slovak population is in Hardy-Weinberg equilibrium and proportion of TYMS polymorphisms is in accordance with other published data.

Can we predict orofacial cleft in future pregnancy?

AIM: The aim of this thesis was not only to define the frequency of all orofacial clefts and their particular types, but also to determine the sex of an embryo or fetus and detect associated developmental and chromosomal abnormalities. Approximately one third of orofacial clefts are a part of chromosomal syndromes. MATERIALS AND METHODS: Retrospective morphological and cytogenetic study of 43 cases of different types of orofacial clefts between 1992-2014 from miscarriages (spontaneous abortions) and premature births. RESULTS: Associated abnormalities were found in 34 cases. Most of the anomalies were skeletal anomalies (29), NTD (24) and anomalies of the abdominal wall (9). Most associated anomalies were found in the R III group (93.3 %). Eleven of the successfully cultivated cases (26 %) had a normal karyotype and in 14 of the cases (32 %), numerical or unbalanced structural chromosomal aberrations were found. CONCLUSION: Our data did not show that isolated clefts were not associated with a higher risk of chromosomal aberrations. Higher percentage of chromosomal aberrations found in isolated clefts in our pool can be explained by the age of the embryos and fetuses - usually between day 43 and week 12. It is nearly impossible to diagnose some associated congenital defects at such an early age. Thanks to the morphological and cytogenetic analysis of embryos and fetuses with orofacial cleft, it is possible to estimate if not determine the etiologic factor which influenced the miscarriage. Additionally, in the case of birth defects, the prognosis for future pregnancy can be offered, which is important information for gynecologist and clinical geneticist (Tab. 5, Fig. 5, Ref. 31).

Cytotoxicity test and cytogenetic analysis of effects of aminoguanidine in vitro.

The potential genotoxic activity of chemical substances in vitro is usually assessed by the micronucleus test and by karyological analysis. Use of the fluorescent plus Giemsa (FPG) technique is also recommended in the event that positive results are found in the micronucleus test, or if there is an increased rate of structural and numerical chromosome aberrations compared with controls. The tested substance, aminoguanidine (AG), has a marked ability to inhibit the toxic effects of carbonyl products (carbonyl stress) that arise during the end-phases of non-enzymatic protein glycation both in vitro and in vivo. The importance of this ability follows the finding that the production of advanced glycation end-products (AGE) is a part of the molecular mechanism of the pathogenesis of chronic diabetic complications. The aim of this study was to test the cytotoxic and clastogenic effects of AG on cells of the diploid cell line B-HEF-2, derived from a three-month-old male fetus. The results of the test did not reveal any induction of micronucleus production in the analyzed cells at AG concentrations ranging between 1 x 10(-2) and 1 x 10(-4) mol.L-1. Karyological analysis showed no clastogenic effect of the tested substance nor any increased rate of structural chromosome aberrations. The positive properties of AG and to its potential use as a glycoxidation inhibitor and AGE production are somewhat dimmed by its ionic nature, which hampers hydrophobic interaction with the nonpolar components of biological membranes. For this reason, the authors will further study the cytotoxicity and cytogenetic analysis of Schiff bases of AG synthesis on the basis of natural aldehydes (resorcine aldehyde, pyridoxal, etc.) in which antiglycation activity has been detected.

Developmental defects and chromosomal aberrations in spontaneous abortions and stillbirths.

The authors analysed 1488 cases of spontaneous abortions and stillbirths in Bratislava. They focused on the course of human embryogenesis and the chromosomal constitution. A high mean frequency rate of both developmental defects (14.4%) and chromosomal aberrations (33.6%) was revealed and both were found to be in close relation with the length of gestation. The most severe developmental defects occurred mostly in early stages of human embryogenesis, i.e. in the 1st trimester of gestation.

[Pathologic karyotypes in autopsy material]. / Patologické karyotypy v súbore nekroptického materiálu.

In 1986-1989 the authors were concerned with the cultivation of necroptic material. Material was collected from five indication groups outlined in advance. A total of 231 specimens of necroptic material were cultivated, incl. 143 specimens subjected to cytological evaluation. From the above material 20 pathological karyotypes were diagnosed. The results of cytogenetic analysis of chromosome abnormalities were compared with the clinical and pathological diagnosis. Post-mortem chromosome analysis is important for elucidation of the aetiopathogenesis of perinatal deaths and for a comprehensive approach to families with genetic risk.

[Postmortem chromosome analysis and its significance]. / Postmortálna chromozómová analýza a jej význam.

Cultivation of necroptic material taken by pathologist or obstetrician according to determined indicative groups was performed during the years 1986-1990. Cytogenetical evaluation was feasible in 157 cultivated samples from the total of 252. There were found 32 pathological karyotypes among them.

[69, XXY triploidy in a liveborn infant]. / Triploidia 69, XXY u zivorodeného dietata.

Triploidy 69, XXY was described in a liveborn foetus weighing 760 g. Diagnosis was based on postmortal cytogenetical analysis.

[Cytogenetic examination of amniotic fluid specimens in the 2d trimester of pregnancy (personal experience 1981-1989)]. / Cytogenetické vysetrenie vzoriek plodovej vody v II. trimestri gravidity (nase skúsenosti za roky 1981-1989).

The authors analyze a group of pregnant women examined at the Chair of Biology and Parasitology of the Medical Faculty J. A. Komensky's University between 1981 and the end of August 1989. During this period they cultivated cells from 1755 specimens of amniotic fluid. In the article they evaluate the detection rate of pathological conditions during this period.

[Experience with postmortem chromosome analysis]. / Skúsenosti s postmortálnou chromozómovou analýzou.

Over the years 1986-1988 necroptic material, collected according to 5 established indication groups, was cultured. A total of 202 samples of necroptic material cultured and 122 of these samples were analyzed cytogenetically. Seventeen pathologic karyotypes were diagnosed in the material, namely 7 cases of Down's syndrome, 2 cases of Klinefelter's syndrome, 2 cases of D/D translocation, 1 case of Turner's syndrome, 1 case of gonosomal mosaicism, and 1 case of Patau's syndrome.