Morphofunctional features of articular cartilage structure.

BACKGROUND: Articular cartilage is highly-organized nonvascularized tissue which is responsible in humans for pressure absorption under load, as well as for the smoothness of the opposite tangential bone surfaces. The purpose of our research is to study structural and functional features of articular cartilage at light- optical level by using state-of-the-art research methods of bone-cartilage tissue. MATERIAL AND METHODS: the study was conducted on samples of femoral heads. Hyper fine sections were subject to hematoxylin and eosin, Van Gieson's and PAS staining. In order to identify the receptor profile of chondrocytes and the features of protein arrangement in extracellular matrix we undertook an immunohistochemical study. RESULTS: An articular cartilage is quite organized tissue. As any other organ, it has parenchyma and stroma. Parenchyma is represented by one type of cells - chondrocytes, which, depending on how deep they are located in cartilage, have a different shape, size and functional features. The chondrocytes and extracellular matrix have different degrees of receptors expression. CONCLUSIONS: the cartilage is being constantly self-renewed, what is manifested by means of a rather slow division of the surface-located chondrocytes and programmed death of dystrophic-modi ed cells. The features of extracellular matrix structure determine the originality of cell location in different areas of cartilage tissue. Due to synthesis of specific proteins, chondrocytes self-regulate properties of cartilage tissue.

Structural features of bone marrow.

PURPOSE: This article is devoted to the investigation of the structural features of the bone marrow of mature rats. MATERIALS AND METHODS: The investigation of the structural features of the bone marrow was performed on the femurs of the mature male rats. General structure of the organ was studied with hematoxylin-eosin and Van Gieson staining of samples. Certain features of the bone marrow structure were studied using immunohistochemical method (CD3, CD79α, S100, myeloperoxidase, and cyclin D1). RESULTS: We can state that stromal-parenchymal structure is typical for the bone marrow of rats as for any other organ. The stromal component is presented with bone tissue (48.8 ± 3.3% at epiphyses), the net of blood vessels (18.7 ± 2.1%), fat tissue (11 ± 2%), fibrous tissue (0.7 ± 0.2%), and the network of reticular fibers. Hematopoietic tissue covers 20.9 ± 3.7% at the femoral epiphyses and 69.6 ± 2.2% at diaphysis. Among these tissues, myelopoiesis occupies 74.2 ± 4.7%, erythropoiesis - 24.3 ± 4.7%, and lymphopoiesis - less than 5%. Megalokaryocytes take 0.1-0.3%. CONCLUSION: Considering the lack of significant anatomical, morphological, and histological differences of red bone marrow of rats and humans, we can state that hematopoiesis in rats takes place on the basis of the same principles as in humans, although it has certain mechanisms.

Pathogenetic mechanisms of heavy metals effect on proapoptotic and proliferative potential of breast cancer.

MATERIALS AND METHODS: Chemical composition was studied with the help of the scanning electron microscope with energy-dispersion spectrometer. Immunohistochemical reaction showed the p53 and Ki-67 receptors expression. The study of DNA fragmentation was performed in agarose gel. RESULTS: There was an interrelation between the accumulations of the trace elements with the degree of cancer malignancy. There were 85% of cases with positive reaction to Ki-67 and 40% cases with positive reaction to p53. We found a moderate correlation between the accumulation of microelements in the breast cancer tissue and the level of proliferative activity. We noted the combination of the increase of DNA fragmentation with the expression of p53 and Ki-67 receptors. CONCLUSIONS: The trace elements can cause the initiation and the progression of the tumorous growth, which is expressed in the increased proliferation of tumor cells. This leads to the destabilization of the genetic material which can be expressed in the synthesis of mutant p53 protein. Finally, it leads to the block of apoptosis and regulatory effects of cells. This can cause the tumor progression and the destabilization of the genome, which is reflected in the increased DNA fragmentation.

Histological and immunohistochemical features of medullary breast cancer.

Disputes take place among many scientists about the position of MC in the classification of breast cancer. Some say that this kind of tumor is a sign of invasive ductal carcinoma (IDC). Instead, most of modern researchers distinguish MC of the breast as a separate nosological unit. Primarily there were selected 20 cases of MC and 10 cases of IDC (as control group). The immunohistochemical study revealed the presence of ER, PR, HER2/neo, p53, Ki-67, MMP1 and E-cadherin receptors. In the study of receptor status of tumors it was observed that 100% of MC cases were estrogen-, progesterone- and HER2/ neu negative. The status of tumors on receptor p53 and Ki-67 was as follows: p53+ status had 80% and Ki-67+ had 85% of tissues of MC. In 75% of cases MC cells expressed marker of adhesion and in 100% of cases cells were receptor-negative for expression of MMP1. The data of the study show that the invasive ductal carcinoma and medullary carcinoma are completely independent and different types of malignancy in the breast. The favorable behavior of medullary cancer is associated with expression of E-cadherin receptors, which are essentially adhesion factor and absence of MMP1 which are factors of metastatic potential of the tumor.