Insights into non-informative results from non-invasive prenatal screening through gestational age, maternal BMI, and age analyses

The discovery of cell-free fetal DNA fragments in the maternal plasma initiated a novel testing method in prenatal care, called non-invasive prenatal screening (NIPS). One of the limitations of NIPS is the necessity for a sufficient proportion of fetal fragments in the analyzed circulating DNA mixture (fetal fraction), otherwise, the sample is uninterpretable. We present the effect of gestational age, maternal body mass index (BMI), and maternal age on the fetal fraction (FF) of the sample. We retrospectively analyzed data from 5543 pregnant women with a single male fetus who underwent NIPS from which 189 samples received a repeat testing due to an insufficient FF. We showed the relationship between the failure rate of the samples after the repeated analysis, the FF, and the gestational age at the first sampling. Next, we found that different maternal BMI categories affect the FF and thus the chance of an informative redraw. A better understanding of the factors affecting the FF will reduce the number of non-informative calls from repeated analyzes. In this study, we provide helpful information to clinicians on how to approach non-informative analyses.

IMPACTS OF HUMIC ACIDS IN NUTRITION ON HAEMATOLOGICAL AND BIOCHEMICAL PARAMETERS OF BROWN HARES

Humic substances are natural organic substances resulting from the decomposition of mainly plant but also animal residues. The objective of our study was to test if the humic acids can negatively/positively affect brown hares health status. As the main indicators for this evaluation, we chose haematological and biochemical blood tests. In this study, we used 24 brown hares (12 males and 12 females) in the age of 12-24 months. As part of the 6-month experiment, we planned three blood samplings (at the beginning of the experiment and then after three and six months). Animals were divided into three groups at the beginning of the experiment (n = 8/group): CG (control group, 0-11KKZ standard diet without additives), EG1 group (experimental group 1, received 0-10KK/D standard feed + 1% of Humac Natur AFM – humic acids), and EG2 group (experimental group 2, received 0-10KK/D standard feed + 1% of Humac Natur AFM – humic acids, enriched with green feed – clover-grass mixture). We found a statistically significant difference between the control group and the EG2 group in the RBC parameter (P < 0.05) after three months of consumption. We found a statistically significant decrease in urea levels in both experimental groups compared to the control group (P < 0.001), as well as a decrease in urea concentration in the EG2 group compared to the EG1 group (P < 0.01); decrease in cholesterol levels in the experimental groups compared to the control, and between EG1 and the control group, this decrease was statistically significant (P < 0.05); and we recorded a statistically significant increase of triglycerides in the EG2 group compared to the other groups (P < 0.01). Based on the obtained results, we can evaluate the use of 1% humic acid as a feed additive as safe for feeding hares.

The occurrence and dynamics of polychlorinated hydrocarbons in roe deer (Capreolus capreolus) in South-western Slovakia

The goal of this study was to determined polychlorinated biphenyls (PCBs) and organochlorine pesticides in the depot fat of roe deer (Capreolus capreolus) coming from south-western Slovakia. The mutual correlations of the organic pollutants were analyzed. The study included dichlorodiphenyltrichloroethane (DDT), hexachlorobenzen (HCB), alpha-hexachlorocyclohexane and beta-hexachlorocyclohexane (α + β-HCH), gamma-hexachlorocyclohexane (γ-HCH), and polychlorinated biphenyls (PCB-delor). The gas chromatograph with an electron capture detector ECD was used for analysis. The accumulations of organic pollutant in depot fat of roe deer were in following order: DDT > PCB-delor > α + β-HCH > HCB > γ-HCH. Among all pollutants, DDT was accumulated significantly in the highest level in the samples. The significantly higher content of DDT, HCB, α + β-HCH, and γ-HCH was detected in the adult animals when compared to the juveniles. Some strong positive correlations among pollutants, between HCB and DDT, α + β-HCH and HCB, α + β-HCH and HCB, between γ-HCH and other pollutants, and between PCB-delor and γ-HCH were found. Game animals are a part of human food chain and monitoring of the environment pollution by PCBs and other organic pollutants are worthy to study.

Seasonal, age and sex fluctuations in aflatoxin B1 content in the liver and kidney of brown hares (Lepus europaeus Pall)

The goal of this study was to monitor the accumulation of aflatoxin B₁ in the liver and kidney of brown hares (Lepus europaeus Pall) in the region of south-western Slovakia. A total of 65 samples were involved for analysis by RIA method. Brown hares were divided into the groups according to age, sex and season (month). The sex was determined visually after shooting, and the age was assigned from dried eye lens. The average concentration of AFB₁ in the liver of hares was 0.54 ± 0.053 µg/kg, and lower values were measured in the kidney (0.41 ± 0.038 µg/kg). The significantly (P < 0.05) higher values were found in winter months when compared to summer months. According to the age, juvenile animals showed significant higher accumulation of B₁ in both organs than adults (P < 0.05). Wild animals can serve as a good model of real environmental contamination. Thus, monitoring of risk factors such as mycotoxins in the environment is important with regard to public health, as game animals constitute an important part of food chain for humans.