This study investigated the quantity and distribution of extracellular polymeric substances (EPS) in aerobic granules. Results showed that EPS play an important role in the formation and stabilisation of granules. The content of EPS significantly increases during the first weeks of biogranulation. An analysis of EPS in the granules revealed that the protein level was 5 times higher than in polysaccharides. The increase of protein content correlated with the growth of cell hydrophobicity (r2 = 0.95). EPS and hydrophobicity are important factors in cell adhesion and formation of granules.

The aim of this work was also to determine the distribution of EPS in the granule structure. In situ EPS staining showed that EPS are located mostly in the center of granules and in the subsurface layer. The major components of the EPE matrix are proteins, nucleic acids and β-polysaccharides. These observations confirm the chemical extraction data and indicate that granule formation and stability are dependent on protein content.

The aim of the study was to assess the course of posterior interosseous nerve in the wrist capsule in the transparent method of nerve staining.

M a t e r i a l a n d M e t h o d s: Thirty dorsal wrist capsules were collected bilaterally from 15 donors (thirty capsules) within 12 hours of death. By the dorsal incision the capsules were collected in the same manner. The specimens were stained according to the protocol of modified Sihler’s staining technique. The preserved capsules were analysed under 8–16× magnification of optical microscope for the presence of major posterior interosseous nerve trunks, their major and minor branches, and nerve connections.

R e s u l t s: Three main types of nerve course were identified within the joint capsule. Type I — the most common, with the presence of a single trunk with the excursion of the first main branch on the radial side, two main branches on the ulnar side, the presence of the prevailing number of small branches on the radial side and the presence of 3–4 branches extending beyond the level of the carpo-metacarpal joints. Type II with the presence of two main nerve trunks, running almost in parallel with the first main branch on the radial side, two main branches on the ulnar side with presence of a predominant number of small branches on the radial side and the presence of 3–4 branches running beyond the level of carpo-metacarpal joints. Type III (least often) with the presence of crossed main nerve trunks.

C o n c l u s i o n: The modified Sihler’s staining technique allows for transparent visibility of the nerves innervation the dorsal wrist capsule. However does not allow accurate assessment as histological examination, especially in evaluation of nerve endings, but it gives a significantly larger area of nerve observation.

The pathologists follow a systematic and partially manual process to obtain histological tissue sections from the biological tissue extracted from patients. This process is far from being perfect and can introduce some errors in the quality of the tissue sections (distortions, deformations, folds and tissue breaks). In this paper, we propose a deep learning (DL) method for the detection and segmentation of these damaged regions in whole slide images (WSIs). The proposed technique is based on convolutional neural networks (CNNs) and uses the U-net model to achieve the pixel-wise segmentation of these unwanted regions. The results obtained show that this technique yields satisfactory results and can be applied as a pre-processing step for automatic WSI analysis in order to prevent the use of the damaged areas in the evaluation processes.

Triploid viviparous onions [Allium x cornutum Clementi ex Visiani 1842, syn Allium cepa L. var. viviparum Metzg. (Alef.), auct.] (2n = 3x = 24), are known in some countries only as rare relict crops. In other parts of the world they are still traditionally or even commercially cultivated. In previous cytogenetic studies of the Croatian triploid viviparous onion Ljutika, Giemsa C-banding, chromosome pairing analysis during meiosis, and genomic hybridization in situ indicated a complex hybrid with highly heterozygous karyotype structure, with possible triparental genome organization. This study continues an analysis of the karyotype structure of Ljutika. Staining with fluorochromes CMA3 (Chromomycin A3) and Dapi (4,6-diamidino-2-phenylindole) confirmed previous results from Giemsa C-banding and revealed GC-rich heterochromatic regions associated mainly with chromosome ends and nucleolus organizing regions (NORs), and only a few interstitial bands. Fish mapping of the ribosomal 18S-5.8S-26S genes revealed two major rDNA signals on the short arms of two subtelocentric satellite chromosomes in almost all metaphase plates of Ljutika. The largest subtelocentric chromosome lacked rDNA signals. A significantly smaller rDNA signal was occasionally located on one small submetacentric chromosome. These results are in agreement with previously published results from identification of NORs by silver-staining technique, which confirmed a maximum three nucleoli in interphase nuclei. We discuss the molecular mechanisms underlying rearrangements and activity of ribosomal genes in the triploid karyotype.