The Spatial-Temporal Dimension of Oncological Prevalence and Mortality in Romania

The objective of this study was to identify spatial disparities in the distribution of cancer hotspots within Romania. Additionally, the research aimed to track prevailing trends in cancer prevalence and mortality according to a cancer type. The study covered the timeframe between 2008 and 2017, examining all 3,181 territorial administrative units. The analysis of spatial distribution relied on two key parameters. The first parameter, persistence, measured the duration for which cancer prevalence exceeded the 75th percentile threshold. Cancer prevalence refers to the total number of individuals in a population who have been diagnosed with cancer at a specific time point, including both newly diagnosed cases (occurrence) and existing cases. The second parameter, the time continuity of persistence, calculated the consecutive months during which cancer prevalence consistently surpassed the 75th percentile threshold. Notably, persistence of elevated values was also evident in lowland regions, devoid of any discernible direct connection to environmental conditions. In conclusion, this work bears substantial relevance to regional health policies, by aiding in the formulation of prevention strategies, while also fostering a deeper comprehension of the socioeconomic and environmental factors contributing to cancer.

High inter-observer reliability in standardized ultrasound measurements of subcutaneous adipose tissue in children aged three to six years

BACKGROUND

A procedure to measure subcutaneous adipose (SAT) using brightness-mode ultrasound has recently been standardized and applied to various groups of adults including underweight, overweight and obese adults. High reliability of this procedure was found in each of the examined groups. The purpose of this study was to determine inter-observer reliability of the standardized brightness-mode ultrasound measurement of uncompressed SAT in three to six-year-old children.

METHODS

Three experienced observers independently captured the ultrasound images at the eight standardized measurement sites in each of the 20 children and evaluated their images using an interactive software that detects the SAT contour and automatically measures multiple thicknesses in each image; the mean of these represents SAT thickness at a given site. The children were aged 4.9 ± 1.0 years; their body mass index ranged from 13.6-17.7 kgm- 2. Sound speed was set to 1450 ms- 1 for SAT.

RESULTS

SAT thickness sums with fibrous structures included (DI) ranged from 25.7-86.4 mm, mean DI was 48.1 ± 15.5 mm. For DI, resulting from 160 measurements by each observer, the intra-class correlation coefficient was 0.998 (95% confidence interval 0.980-0.999), standard error of the estimate was 1.1 mm, and 95% limits of agreement were within ±2.1 mm. The median difference in DI was 0.8 mm, i.e. about 1.9% of mean DI.

CONCLUSIONS

Inter-observer results in children are comparable to previously described high reliability in adults. This method, which provides a technical thickness measurement accuracy of about 0.1 to 0.2 mm, enables monitoring of subcutaneous adipose tissue in children with a similarly high reliability as was obtained in adults previously.

TRIAL REGISTRATION

German Institute of Medical Documentation and Information, German Clinical Trials Register (DRKS) ID: DRKS00010089; Date 24/02/2016.

Distribution of decidual natural killer cells and macrophages in the neighbourhood of the trophoblast invasion front: a quantitative evaluation

STUDY QUESTION

Do decidual natural killer (dNK) cells and decidual macrophages (dMph) become enriched in the vicinity of the trophoblast invasion front?

SUMMARY ANSWER

Morphometric image analysis and areal cell density calculations, which excluded observer bias, showed an enrichment of decidual leukocytes in the neighbourhood of the trophoblast invasion front.

WHAT IS KNOWN ALREADY

In previous studies, the number of decidual leukocytes was visually counted in medium- or high power fields. These methods, however, cannot reveal the exact spatial relationship between leukocytes and invasive trophoblast cells, and are therefore prone to subjective errors. Thus, a more objective approach is required.

STUDY DESIGN, SIZE, DURATION

Applying a new method of morphometric image analysis, leukocyte populations were studied in human tissue fragments derived from first trimester placentation sites (n = 7) as well as in co-cultures of first trimester decidual tissue with placental villi of the same pregnancy representing an appropriate in vitro model of trophoblast invasion (n = 15).

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

First trimester decidual tissue was obtained from women undergoing elective terminations of pregnancy at 7-10 weeks of gestational age. Tissue sections were double-stained immunohistochemically for markers of dNK cells or dMph on one hand, and for invasive extravillous trophoblast cells on the other. To analyse the distribution of leukocytes, distinct cell compartments as well as cell neighbourhood areas were defined. Finally, relative areal cell densities were calculated and these data were compared with those of an in vitro model of trophoblast invasion as well as with tissue fragments derived from decidua parietalis without trophoblast cells.

MAIN RESULTS AND THE ROLE OF CHANCE

At first trimester placentation sites, a higher density of dNK cells as well as of dMph was found in close proximity to the invasive trophoblast (P ≤ 0.01), compared with the average areal cell density of decidual leukocytes in the tissue with exclusion of the trophoblast. The highest areal cell density of leukocytes was determined up to a distance of 20 μm from the trophoblast cells, whereas in more distant regions it was even lower than average, indicating a migration of these leukocytes towards the trophoblast invasion front. In the three-dimensional co-culture model, however, we found an enrichment of dMph (P ≤ 0.01) but not of dNK cells (P > 0,05) in the neighbourhood of the invasive trophoblast.

LIMITATIONS, REASONS FOR CAUTION

The morphometric image analysis depends on intense immunohistochemical staining that is free of background and cross-reactivity.

WIDER IMPLICATIONS OF THE FINDINGS

The presented method will be useful not only for the investigation of recurrent miscarriage but also in the fields of tumour immunology and inflammation.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by the European Commission (Network of Excellence 'The Control of Embryo Implantation (EMBIC)', FP6-512040, lead researcher: P.S.), and by the Franz Lanyar Foundation of the Medical University of Graz, Austria (Grant #347). None of the authors declared a conflict of interests.

Fractal dimension of K1735 mouse melanoma clones and spheroid invasion in vitro

An in vitro tumour-host confrontation method to investigate the invasion behaviour of cancer has been applied to K1735 mouse melanomas. Fluorescently labelled spheroids of cancer cells and host cells were confronted and the temporal course of cancer invasion into the host was investigated using confocal laser scanning microscopy. To improve the quantitative data of this method, the boundary images of the fluorescently labelled confrontation pairs were treated as fractals. The physical and mathematical framework for determination of the fractal capacity dimension is widely used in biology and medicine and has proved to be a very useful tool for describing the cancer invasion process. The fractal capacity dimension determination was carried out by dilation of the binary boundaries of the objects, which were treated as an estimate of the Minkowski-Bouligand dimension. The fractal dimension correlated well with the degree of invasion of the K1735-M2 clone. Control experiments, with host-host confrontations and various K1735 clones with reduced invasiveness, support these results.

Cross-talk reduction in confocal images of dual fluorescence labelled cell spheroids

Dual fluorescence labelling is an advanced method to separate two individual specimens in a biological system using confocal microscopy. An inherent problem of this method is fluorescence channel cross-talk, which causes problems for the exact spatial determination and separation of the specimens. Using a parallel fluorescence detection and an image processing technique, based on an image subtraction method, we have developed a very straight forward method for correcting the dual channel fluorescence images. We successfully applied this method to a 3-dimensional cancer spheroid invasion assay and controlled the cross-talk compensation efficiency by a quality parameter.

Optical multisite monitoring of cell excitation phenomena in isolated cardiomyocytes

An especially designed setup which consists of an inverted fluorescence microscope, an argon ion laser and a photodiode array system permits membrane potential monitoring in isolated guinea-pig ventricular cardiomyocytes, stained with the voltage-sensitive dye di-4-ANEPPS, which responds linearly with relative fluorescence changes (delta F/F) approximately -8% per 100 mV. About a dozen measuring spots covering a single cell were simultaneously monitored with a spatial and temporal resolution of 15 microns and about 20 microseconds, respectively. In general, the rising phases of the action potentials within a single cell were highly synchronized (i.e. all upstroke velocities peaked within about 20 microseconds); however, in one cell (out of 25 examined) significant (P < 0.05) time lags exceeding the signal-dependent time resolution were also found. Experiments, simultaneously performed with our optical system and a widely used patch-clamp setup, revealed a slowed and delayed response of the clamp amplifier depending on the cell access resistance. Optical monitoring during whole-cell voltage-clamping demonstrated the influence of graduated series resistance compensation. When field stimulation was used, our results clearly demonstrated the spatially dependent polarization of the cell membrane during the stimulus, as well as a highly synchronized upstroke development. Slight differences in the maximum upstroke velocities within a single cell were also found and were basically in agreement with mathematical models.

Di-4-ANEPPS causes photodynamic damage to isolated cardiomyocytes

Action potential recordings from isolated guinea pig ventricular cells in the whole-cell recording mode were used to study the toxic and photodynamic properties of the voltage-sensitive fluorescent dye di-4-ANEPPS. Staining of the cardiomyocytes with di-4-ANEPPS (30 or 60 microM; 10 min) did not alter the action potential shape. When the stained cells were illuminated (1W/cm2) severe effects on the action potential were observed. There was a prolongation of the action potential duration, occurrence of early afterdepolarizations, reduction of the membrane resting potential and eventually inexcitability. Addition of the antioxidant catalase (100 IU/ml) to the extracellular solution delayed the onset of these effects, suggesting that reactive-oxygen-intermediates take part in di-4-ANEPPS induced photodynamic damage. Since di-4-ANEPPS is a very important tool for optical membrane potential recordings in heart tissue and single cardiomyocytes catalase might be useful in suppressing photodynamic damage during optical potential recordings.