Wastewater-based epidemiology in countries with poor wastewater treatment - Epidemiological indicator function of SARS-CoV-2 RNA in surface waters.

Wastewater-based epidemiology (WBE) surveillance of COVID-19 and other future outbreaks is a challenge for developing countries as most households are not connected to a sewerage system. In December 2019, SARS-CoV-2 RNA was detected in the Danube River at a site severely affected by wastewaters from Belgrade. Rivers are much more complex systems than wastewater systems, and efforts are needed to address all the factors influencing the adoption of WBE as an alternative to targeting raw wastewater. Our objective was to provide a more detailed insight into the potential of SARS-CoV-2 surveillance in Serbian surface waters for epidemiological purposes. Water samples were collected at 12 sites along the Sava and Danube rivers in Belgrade during the fourth COVID-19 wave in Serbia that started in late February 2021. RNA was concentrated using Amicon Ultra-15 centrifugal filters and quantified using RT-qPCR with primer sets targeting nucleocapsid (N1 and N2) and envelope (E) protein genes. Microbiological (faecal indicator bacteria and human and animal genetic faecal source tracking markers), epidemiological, physicochemical and hydromorphological parameters were analysed in parallel. From 44 samples, SARS-CoV-2 RNA was detected in 31, but only at 4 concentrations above the level of quantification (ranging from 8.47 × 103 to 2.07 × 104 gc/L). The results indicated that surveillance of SARS-CoV-2 RNA in surface waters as ultimate recipients could be used as an epidemiological early-warning tool in countries lacking wastewater treatment and proper sewerage infrastructure. The performance of the applied approach, including advanced sampling site characterization to trace and identify sites with significant raw sewage influence from human populations, could be further improved by adaptation of the methodology for processing higher volumes of samples and enrichment factors, which should provide the quantitative instead of qualitative data needed for WBE.

Contribution to the knowledge of the bee fauna (Hymenoptera, Apoidea, Anthophila) in Serbia.

The current work represents summarised data on the bee fauna in Serbia from previous publications, collections, and field data in the period from 1890 to 2020. A total of 706 species from all six of the globally widespread bee families is recorded; of the total number of recorded species, 314 have been confirmed by determination, while 392 species are from published data. Fourteen species, collected in the last three years, are the first published records of these taxa from Serbia: Andrenabarbareae (Panzer, 1805), A.clarkella (Kirby, 1802), A.fulvicornis (Schenck, 1853), A.intermedia (Thomson, 1870), A.lapponica (Zetterstedt, 1838), A.pandellei (Pérez, 1895), A.paucisquama (Noskiewicz, 1924), A.simillima (Smith, 1851), Panurginusherzi (Morawitz, 1892), Epeoloidescoecutiens (Fabricius, 1775), Nomadaleucophthalma (Kirby, 1802), Chelostomanasutum (Pérez, 1895), Hoplitisclaviventris (Thomson, 1872), and Dasypodapyrotrichia (Förster, 1855). Almost all the species recorded so far in Serbia belong to the West-Palaearctic biogeographical region, except Megachilesculpturalis (Smith, 1853), which is an alien invasive species native to East Asia. According to the European Red List of bees, 221 species listed in this paper were assessed as Data Deficient; threatened species mostly belong to the families Apidae with 13 species, Colletidae with eight species, and Halictidae with five species. This study contributes to the knowledge of the distribution of bee species in Europe. The present work provides a baseline for future research of wild bee diversity in Serbia and neighbouring regions at the local and regional levels, and a basis for their conservation.

The analysis of factors associated with improved glycemic control in patients with insulin-requiring type 2 diabetes mellitus after treatment.

AIM: To observe the effect of standardized ten-day diabetes prevention and control program on glycemic control, and to analyze factors contributing significantly to improvement of glycemic control after the program/intervention. METHODS: A cross-sectional nested case-control study on 91 adult patients with insulin-requiring type 2 diabetes mellitus who underwent a standardized ten-day diabetes program in the Specialized Hospital "Merkur" in Vrnjacka Banja, Serbia, from June the 1st to August 1st 2010 was performed. All necessary data were obtained from patients' medical files archived in this institution. Cases (n=32) and controls (n=32) were matched for age and sex. RESULTS: Diabetes program led to a significant decrease in mean daily blood glucose (p=0.039), achieved at the expense of the reduction of postprandial hyperglycemia (p=0.013). Male patients, patients with mean daily glycemia above the acceptable range before the intervention, and patients who were receiving combined therapy (insulin plus oral antidiabetics) before the intervention, were significantly more likely to achieve such positive outcome (ORadjusted = 344.48, 12.83, and 25.44 respectively, with 95%CIs that not included 1). CONCLUSION: Standardized ten-day diabetes educational and rehabilitation program in the Specialized Hospital "Merkur" could be efficient in improving glycemic control, especially for male patients whose glucoregulation was poor despite the combined therapy with insulin and oral antidiabetic agents. Further investigation on determinants of efficiency of this program are necessary to understand better how to facilitate and support improvements in diabetes control at the population level.

[Correlation of sera concentrations of thyroperoxidase autoantibodies measured by two radioimmunoassays].

INTRODUCTION: Thyroid peroxidase-specific autoantibodies (TPO Abs) are mostly measured in patients with autoimmune thyroid diseases. The aim of this study was to compare TPO Ab concentrations measured by two radioimmunoassays. MATERIAL AND METHODS: Our investigation included 38 patients. Sera concentrations of TPO Abs were measured by using Cis biointernational (France) and Immunotech (Czech Republic) assays. RESULTS: Concentrations obtained by two assays were extensively different. The values measured by Cis biointernational assay were higher than ones obtained by Immunotech assay. The statistical arrangement of results showed the direct correlation between the two assays, with the coefficient of agreement R = 0.6239 (p < 0.001). The analysis of relative values (ratio of measured and upper limit values given by the manufacturer) demonstrated the statistically significant difference (p = 0.003) between values measured by Cis biointernational (18.94 +/- 37.22) and by Immunotech assay (4.22 +/- 8.22) concerning the distinction between normal and raised concentrations of TPO Abs. The agreement of results (enhanced or normal TPO Ab concentrations in both tests) was shown in 30 sera samples (78.95%), but in residual 8 sera (21.05%) normal TPO Ab concentrations were obtained by Immunotech, and enchanced by Cis biointernational assay. There is no difference in capability of distinction between normal and pathological results between the two tests (chi12 = 3.484, p > 0.05). The highest concentration of TPO Ab measured by Cis biointernational assay was not the highest one in Immunotech assay, which might be a reflection of different specificity of antibodies used in two diagnostic tests. CONCLUSION: TPO Ab concentrations obtained by Cis biointernational and Immunotech assays are very different. In several sera samples, normal concentrations of TPO autoantibodies were obtained by Immunotech assay and enhanced by Cis biointernational assay. The highest value obtained by one is not the highest value measured by another assay we used.

[Hyperlipidemia and pregnancy].

During pregnancy of healthy women, it is usual for blood lipids to increase significantly. Total cholesterol, HDL- and LDL-cholesterol increase 25-50%, while triglycerides increase twice to four times, and there is also an increase ofapolipoproteins B. However, this lipid expansion in blood does not lead to endothelial disfunction. Clinical problem are therapy dilemas about the women who were treated with antihyperlipemics during preconception period, possibility of diagnosing hyperlipidemia in pregnancy and their treatment during the pregnancy, then lactacy. It is generally accepted that neither of antihyperlipemic groups is completely harmless to be applied in preconception period, pregnancy and lactacy period. Those patients who had low to medium increased values of triglycerides prior to pregnancy may develop severe hypertriglyceridemia, especially in the third trimester. They must be educared about dietetic measures and body mass reduction even in preconcepticon period, while during pregnancy they must be supervised and in case of triglycerides increase above 11.5 mmol/l and the resulting risk of pancreatitis, other therapy options must be taken into consideration. In women who had hypercholesterolemia before pregnancy as well as those who developed it only during pregnancy, there is a risk of atherosclerosis development in fetus at the birth itself. Besides, children born by mothers with hypercholesterolemia have a risk of faster progression of these fatty streak during the first living year. Although statins do not represent major teratogenic substances in human pathology, it is advised to stop their application either before conception in planned pregnancy, or at the very moment when pregnany is confirmed (abortions are not encouraged).

Correlation of thyroglobulin concentrations measured by radioimmunoassay and immunoradiometric assay and the influence of thyroglobulin antibody.

There are a large number of commercial diagnostic assays for measuring thyroglobulin (Tg) concentration in human serum. The assay principle, as well as the potential presence of antithyroglobulin autoantibody (TgAb) in patient's serum, could influence the measured amount of Tg. Our objective was to determine the concentration of Tg by radioimmunoassay and immunoradiometric assay, to compare the values obtained and to investigate the influence of TgAbs on those results. Analysis of serum specimens (n = 58) showed close correlation between the investigated assays, regardless of the presence of TgAb in some samples. The mean value for Tg concentration, determined by radioimmunoassay, was 25% lower than that obtained by immunoradiometric assay. However, this ratio was not uniform for the whole population because the differences were more prominent for high values of Tg. The significant difference between these two methods was confirmed by Student's t-test, which indicated that patients must be monitored in continuity only by one selected method.

[Phagocytic activity of peripheral blood leukocytes during acute myocardial infarction]. / Fagocitna aktivnost leukocita periferne krvi tokom akutnog infarkta miokarda.

INTRODUCTION: Coronary occlusion may cause acute myocardial infarction associated with many cellular and humoral disturbances of the immune system. The aim of this investigation was to examine phagocytic activity of peripherial blood monocytes and neutrophils as potential cellular markers of systemic immunological events in acute myocardial infarction. MATERIAL AND METHODS: This study included thirty patients following first acute myocardial infarction and thirty healthy volunteers. Immunological analyses were performed on admission and repeated on the second and seventh days after the acute event. Monocytes and neutrophils were obtained from heparinized whole blood after centrifugation and separation on density gradient and incubated with fixed number of heat inactivated and painted particles of yeast. We investigated the following parameters of phagocytic activity: percentage of phagocytosis, phagocytic index, absolute phagocytic index, phagocyte count in a fixed volume of peripherial blood and phagocytic capacity. RESULTS: Except phagocytic index, all phagocytic parameters of monocytes and neutrophils were increased in acute myocardial infarction patients on admission and on the second day of hospitalization. On the seventh day after acute event only the mononuclear phagocyte count in fixed volume of peripheral blood showed significant increase in acute myocardial infarction patients, while percentage of phagocytosis, phagocyte count in fixed volume of peripheral blood and phagocyte capacity of neutrophils were increased during the whole investigated period. CONCLUSION: These data suggest that acute myocardial infarction was followed with strong systemic inflammatory response to myocardial damage. Furthermore, activated monocytes and neutrophils could be a significant source of free radicals, which might be involved in lipid peroxidation and cause tissue damage in early postinfarction period.