The aim of this study was to describe and illustrate the morphology of the stomach, liver, intestine, and their vasculature to support the planning of surgical therapeutic methods in abdominal cavity. On adult Wistar rats corrosion casts were prepared from the arterial system and Duracryl Dental and PUR SP were used as a casting medium and was performed macroscopic anatomical dissection of the stomach, liver, and intestine was performed. The rat stomach was a large, semilunar shaped sac with composite lining. On the stomach was very marked fundus, which formed a blind sac (saccus cecus). The rat liver was divided into six lobes, but without gall bladder. Intestine of the rat was simple, but cecum had a shape as a stomach. The following variations were observed in the origin of the cranial mesenteric artery. On the corrosion cast specimens we noticed the presence of the anastomosis between middle colic artery (a. colica media) and left colic artery (a. colica sinistra). We investigated the second anastomosis between middle colic artery and left colic artery. The results of this study reveal that the functional anatomical relationship between the rat stomach, liver and intestine is important for the development of surgical research in human and veterinary medicine.

It was recently shown that the conditioned medium (CM) of mesenchymal stem cells can enhance viability of neural and glial cell populations. In the present study, we have investigated a cell-free approach via CM from rat bone marrow stromal cells (MScCM) applied intrathecally (IT) for spinal cord injury (SCI) recovery in adult rats. Functional in vitro test on dorsal root ganglion (DRG) primary cultures confirmed biological properties of collected MScCM for production of neurosphere-like structures and axon outgrowth. Afterwards, rats underwent SCI and were treated with IT delivery of MScCM or vehicle at postsurgical Days 1, 5, 9, and 13, and left to survive 10 weeks. Rats that received MScCM showed significantly higher motor function recovery, increase in spared spinal cord tissue, enhanced GAP-43 expression and attenuated inflammation in comparison with vehicle-treated rats. Spared tissue around the lesion site was infiltrated with GAP-43-labeled axons at four weeks that gradually decreased at 10 weeks. Finally, a cytokine array performed on spinal cord extracts after MScCM treatment revealed decreased levels of IL-2, IL-6 and TNFα when compared to vehicle group. In conclusion, our results suggest that molecular cocktail found in MScCM is favorable for final neuroregeneration after SCI.

Biopolymer composites allow the creation of an optimal environment for the regeneration of chondral and osteochondral defects of articular cartilage, where natural regeneration potential is limited. In this experimental study, we used the sheep animal model for the creation of knee cartilage defects. In the medial part of the trochlea and on the medial condyle of the femur, we created artificial defects (6 × 3 mm²) with microfractures. In four experimental sheep, both defects were subsequently filled with the porous acellular polyhydroxybutyrate/chitosan (PHB/CHIT)-based implant. Two sheep had untreated defects. We evaluated the quality of the newly formed tissue in the femoral trochlea defect site using imaging (X-ray, Computer Tomography (CT), Magnetic Resonance Imaging (MRI)), macroscopic, and histological methods. Macroscopically, the surface of the treated regenerate corresponded to the niveau of the surrounding cartilage. X-ray examination 6 months after the implantation confirmed the restoration of the contour in the subchondral calcified layer and the advanced rate of bone tissue integration. The CT scan revealed a low regenerative potential in the bone zone of the defect compared to the cartilage zone. The percentage change in cartilage density at the defect site was not significantly different to the reference area (0.06–6.4%). MRI examination revealed that the healing osteochondral defect was comparable to the intact cartilage signal on the surface of the defect. Hyaline-like cartilage was observed in most of the treated animals, except for one, where the defect was repaired with fibrocartilage. Thus, the acellular, chitosan-based biomaterial is a promising biopolymer composite for the treatment of chondral and osteochondral defects of traumatic character. It has potential for further clinical testing in the orthopedic field, primarily with the combination of supporting factors.

BACKGROUND:The laboratory rat is one of the most popular experimental models for the experimental surgery of the liver. The objective of this study was to investigate the morphometric parameters, physiological data, differences in configuration of li...

Reconstruction of bone defects and maintaining the continuity of the mandible is still a challenge in the maxillofacial surgery. Nowadays, the biomedical research within bone defect treatment is focussed on the therapy of using innovative biomaterials with specific characteristics consisting of the body’s own substances. Hydroxyapatite ceramic scaffolds have fully acceptable phase compositions, microstructures and compressive strengths for their use in regenerative medicine. The innovative hydroxyapatite ceramics used by us were prepared using the tape-casting method, which allows variation in the shape of samples after packing hydroxyapatite paste to 3D-printed plastic form. The purpose of our qualitative study was to evaluate the regenerative potential of the innovative ceramic biomaterial prepared using this method in the therapy of the cortical bone of the lower jaw in four mature pigs. The mandible bone defects were evaluated after different periods of time (after 3, 4, 5 and 6 months) and compared with the control sample (healthy cortical bone from the opposite side of the mandible). The results of the morphological, clinical and radiological investigation and hardness examination confirmed the positive regenerative potential of ceramic implants after treatment of the mandible bone defects in the porcine mandible model.

Novel calcium phosphate cements containing a mixture of four amino acids, glycine, proline, hydroxyproline and either lysine or arginine (CAL, CAK) were characterized and used for treatment of artificial osteochondral defects in knee. It was hypothesized that an enhanced concentration of extracellular collagen amino acids (in complex mixture), in connection with bone cement in defect sites, would support the healing of osteochondral defects with successful formation of hyaline cartilage and subchondral bone. Calcium phosphate cement mixtures were prepared by in situ reaction in a planetary ball mill at aseptic conditions and characterized. It was verified that about 30–60% of amino acids remained adsorbed on hydroxyapatite particles in cements and the addition of amino acids caused around 60% reduction in compressive strength and refinement of hydroxyapatite particles in their microstructure. The significant over-expression of osteogenic genes after the culture of osteoblasts was demonstrated in the cement extracts containing lysine and compared with other cements. The cement pastes were inserted into artificial osteochondral defects in the medial femoral condyle of pigs and, after 3 months post-surgery, tissues were analyzed macroscopically, histologically, immunohistochemically using MRI and X-ray methods. Analysis clearly showed the excellent healing process of artificial osteochondral defects in pigs after treatment with CAL and CAK cements without any inflammation, as well as formation of subchondral bone and hyaline cartilage morphologically and structurally identical to the original tissues. Good integration of the hyaline neocartilage with the surrounding tissue, as well as perfect interconnection between the neocartilage and new subchondral bone tissue, was demonstrated. Tissues were stable after 12 months’ healing.