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  • Author: Dorota Bukowska x
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Splenic Leiomyoma in Dog

Abstract

Leiomyoma is a benign tumour, originating from smooth muscles cells. This tumor commonly involves the uterus, vagina, stomach, intestine, urinary bladder and other organs. Only a few cases of splenic leiomyoma in dogs have been reported in the available literature. Much more frequently malignant leiomyosarcoma was found. The aim of this study was to compile rare clinical case of splenic leiomyoma in dog, which developed with no clinical signs and no abnormalities in blood findings. A 14-year-old, spayed bitch was examined with ultrasonography, where lesions on the spleen were identified. Based on the clinical findings (blood test in norm, no metastases in X-ray examination) surgical removal of spleen was recommended. Two fragments of tumors were prepare for histopathological examination. The lesion was described as smooth muscle benign tumor, therefore a diagnosis of leiomyoma was made. About a year after splenectomy no signs of metastases were present in a ultrasound and X-ray examinations. This report indicates the necessity of taking the occurrence of benign lesions in the spleen into account. Splenectomy based on the presence of tumor lesion should be associated with histopathological examination to identify the nature of change. This clinical case, despite a marked morphological lesion shown during intraoperative examination, was benign with successful prognosis.

Open access
Stemness specificity of epithelial cells – application of cell and tissue technology in regenerative medicine

Abstract

Stem cells are cells that have the potential to replicate and/or differentiate, becoming any tissue. This process could be theoretically repeated indefinitely and can be used to create or fix damaged parts any organ. There are many in vivo factors that cause stem cells to replicate and differentiate. Many of these interactions and mechanisms are still unknown. In vitro models have been successful in inducing stem cells to differentiate into the desired lineage using controlled methods. Recently, epithelial tissue has been successfully created using scaffolds on which stem cells are grown in vitro and then transplanted into the host. This transition creates significant problems. This is because in vitro -grown stem cells or stem cell-derived tissues are created in an isolated environment where virtually every aspect can be monitored and controlled. In vivo monitoring and controlling is significantly more difficult for a plethora of reasons. Cells in the body are constantly exposed to many signals and molecules which affect them. Many of the mechanisms behind these interactions and reactions are known but many others are not. As the corpus of knowledge grows, stem cells become closer to being applied in a clinical setting. In this paper, we review the current evidence on stem cell therapy in regenerative medicine and some of the challenges this field faces.

Open access
Coexistence of pancreatic adenocarcinoma and a pseudocyst in cat

Abstract

Exocrine pancreatic tumors in cats and dogs are very uncommon, with exocrine pancreatic adenocarcinoma described as a particularly rare, malignant tumor in a small animals. It is usually derived from pancreatic ducts, as well as glandular tissue. Very often the disease has a subclinical course and is diagnosed only during post – mortem examination. Adenocarcinoma metastasize to both the surrounding and distant organs. The etiology of the cancer progress in the pancreas remains unknown.

Pancreatic pseudocyst (pseudocystis pancreatis) is a very rare disease in domestic animals. Only a few cases of pancreatic pseudocyst in dogs and cats are described in the available literature. On the other hand, in humans it is a common complication of pancreatitis. The pancreatic pseudocyst can be a result of pancreatitis, as well as be a secondary condition to acute pancreatitis, trauma or chronic inflammation. It is a capsule made of fibrous or granulation tissue, containing sterile pancreatic juice. The pathogenesis of pancreatic pseudocyst is still unknown. Clinical signs are not specific and may resemble symptoms of pancreatitis. The ultrasound examination shows a cyst in the pancreas.

This paper describes the case of pancreatic adenocarcinoma in a cat that occurred simultaneously with the pancreatic pseudocyst. Currently, literature indicates the necessity to differentiate the above cancer from cystic lesion. Due to the simultaneous occurrence of both pathologies, extremely rare diagnosis and spectacular picture of changes, it was decided to present this case.

Open access
Genes regulating programmed cell death are significantly upregulated in porcine immature oocytes

Abstract

Correct maturation of the oocyte is crucial for further fertilization and embryogenesis. It comprises of both nuclear and cytoplasmic maturation, during which the proteins, nutrients and mRNAs are assembled. Cumulus cells are connected with the oocyte via gap-junctions, which enable bi-directional transfer of molecules, forming cumulus-oocyte complex (COC). The expression pattern in CCs is thought to resemble the genes expressed in the oocyte. The CCs surrounding the gamete of high developmental competence have an increased expression of apoptotic markers. Therefore, our aim in this study was to determine whether any apoptosis-related genes are upregulated in porcine oocytes before or after IVM. We isolated COCs from 45 pubertal crossbred gilts, performed brilliant cresyl blue (BCB) staining and analyzed the gene expression pattern in oocytes before and after IVM with the use of microarray analysis. The results include 419 differentially expressed transcripts, 25 of which belong to „regulation of apoptosis” and „regulation of cell death” GO BP terms. This set of genes includes BCLAF1, EIF2AK3, KLF10, MIF, MAP3K1, NOTCH2, TXNIP and APP, all of which have been upregulated in immature porcine oocytes. Our results suggest that they play part in porcine oocyte maturation and could be used as potential markers of female gamete’s developmental competence. This knowledge could serve as a basis to improve ART in pigs.

Open access
Characteristic of factors influencing the proper course of folliculogenesis in mammals

Abstract

Folliculogenesis is the process of ovarian follicle formation,, taking presence during foetal period. During the follicular development, oogoniums undergo meiosis and oocytes are formed. In the ovaries of new born sows, primary and secondary follicles are present and, 90 days after birth, tertiary follicles appear. During development in the ovarian follicles growth of granulosa cells and differentiation of the thecal cells can be observed. A cavity filled with follicular fluid appears. Granulosa cells are divided into: mural cells and corona radiata, which together with the oocyte form the cumulus oophorus. Corona radiata cells, mural layers and oolemma contact each other by a network of gap junctions. Secreted from the pituitary gland, FSH and LH gonadotropin hormones act on receptors located in granular and follicular cells. In the postnatal life tertiary follicles and Graafian follicles are formed. When the follicle reaches a diameter of 1 mm, further growth depends on the secretion of gonadotropins. Mature ovarian follicles produce: progestins, androgens and oestrogens. The growth, differentiation and steroidogenic activity of ovarian follicles, in addition to FSH and LH, is also affected by prolactin, oxytocin, steroid and protein hormones, numerous proteins from the cytokine and interleukin family, metabolic hormones like insulin, glucocorticoids, leptin, thyroid hormones and growth hormones. Despite numerous studies, many processes related to folliculogenesis have not been discovered Learning the mechanisms regulating reproductive processes would allow to easily distinguish pathological processes and discover more and more genes and mechanisms of their expression in cells that build ovarian follicles.

Open access
The use of mesenchymal stem cells in veterinary medicine

Abstract

Constant advances in medicine, both human and veterinary, lead to continuous discovery of new drugs and treatments. Recently, the aspect of stem cell use in regenerative medicine has been very popular. There are still too few clinical trials on animals that could precisely estimate the therapeutic efficacy of cell therapy. However, stem cells are a source of extraordinary potential for multiplication and differentiation which, if used properly, can prove to be an effective mean of treatment of numerous diseases that are currently considered untreatable. The purpose of review is the characterization and clinical use of stem cells in mostly occurring diseases. Particular attention has been given to the issue of mesenchymal stromal cells, which so far have been most widely used in clinical practice. Current research into stem cells has allowed scientists to discover many different types of these cells, describe their characteristics and divide them into groups, with the most important being embryonic stem cells and somatic (adult) stem cells. Adult stem cells, due to their availability and lack of ethical problems, are used in veterinary practice. Different types of mesenchymal stem cells are distinguished, based on their origin. Adipose tissue derived stem cells and stromal vascular fraction find the widest clinical application. In veterinary medicine, stem cells therapies are most commonly used in the case of horse orthopedic injuries and in diseases of various origin in dogs and cats. While further research is needed to confirm the effectiveness of cell therapies, they have much potential to find plenty of potential applications in future medicine.

Open access
Pathogenesis and pathophysiology of ovarian follicular cysts in mammals

Abstract

Ovarian cysts remain to be one of the most common and serious problems in reproduction of farm animals, as well as humans. Apart from causing the fall in reproductive potential of the ovaries, occupying the place in which folliculogenesis and oogenesis occur, they also cause hormone imbalances, by preventing corpus luteum formation, hence lowering the amount of steroid hormone production. While singular cysts rarely affect fertility, hormone fluctuations that are associated with their presence promotes their multiplication, which usually has more adverse effects. While the cysts are easily detectable in humans, possessing distinct echography while examined by ultrasound, multiple factors prevent widespread use of effective detection methods among large herds of farm animals. Because of lack of noticeable symptoms of early stages of such malignancies, they rarely get detected before the animal stops to exhibit symptoms of heat. That causes scientific research to be focused on not only methods of detection, but also the ways to negate the effects of ovarian cysts and bring the affected specimen back to reproductive potential. Despite that, high costs of diagnosis and treatment, cause them to be uncommon on commercial farms. As lack of fertility eliminates animals from breeding purposed herds, ovarian cysts persist as a cause of large losses of the animal husbandry business. Continuous research, focused on natural examples of ovarian cysts should be conducted, in order to improve methods of detection, prevention, treatment and recovery from the effects of ovarian cysts.

Open access
Protein oligomerization is the biochemical process highly up-regulated in porcine oocytes before in vitro maturation (IVM)

Abstract

A wide variety of mechanisms controlling oligomerization are observed. The dynamic nature of protein oligomerization is important for bioactivity control. The oocyte must undergo a series of changes to become a mature form before it can fully participate in the processes associated with its function as a female gamete. The growth of oocytes in the follicular environment is accompanied by surrounding somatic cumulus (CCs) and granulosa cells (GCs). It has been shown that oocytes tested before and after in vitro maturation (IVM) differ significantly in the transcriptomic and proteomic profiles. The aim of this study was to determine new proteomic markers for the oligomerization of porcine oocyte proteins that are associated with cell maturation competence. The Affymetrix microarray assay was performed to examine the gene expression profile associated with protein oligomerization in oocytes before and after IVM. In total, 12258 different transcriptomes were analyzed, of which 419 genes with lower expression in oocytes after IVM. We found 9 genes: GJA1, VCP, JUP, MIF, MAP3K1, INSR, ANGPTL4, EIF2AK3, DECR1, which were significantly down-regulated in oocytes after IVM (in vitro group) compared to oocytes analyzed before IVM (in vivo group). The higher expression of genes involved in the oligomerization of the protein before IVM indicates that they can be recognized as important markers of biological activation of proteins necessary for the further growth and development of pig embryos.

Open access
Transforming growth factor (TGF) – is it a key protein in mammalian reproductive biology?

Abstract

The superfamily of transforming growth factors β (TGF-β) consists of cytokines that are crucial in regulating the organism’s biological functions and includes three isoforms of TGF-β protein, Anti-Müllerian Hormone (AMH), inhibin A and B, activins, 20 bone morphogenetic proteins (BMP1-20) and 9 growth factors (GDF1-9). Their signal transduction pathway involves three types of membrane receptors that exhibit a serine/threonine kinase activity, as well as the Smad proteins. After ligand binding, the Smad proteins are phosphorylated and translocated to the nucleus, where they interact with transcription factors and affect gene expression. TGF-β family members are involved in cell growth and differentiation, as well as chemo-taxis and apoptosis, and play an important role during an inflammation. Defects in TGF-β proteins or in their signalling pathway underlie many severe diseases, such as systemic lupus, systemic scleroderma, bronchial asthma, atherosclerosis, hyperthyroidism or cancer. These factors are also crucial in mammal reproductive functions, as they are involved in folliculogenesis, steroidogenesis, ovulation, maternal-embryo interaction, embryo development and uterine decidualization. Their defects result in issues with fertility. This review focuses on the relevance of TGF-β family members in a mammal reproduction with an emphasis on three TGF-β isoforms, inhibins A and B, GDF-9 and their signal transduction pathway.

Open access
Cytoplasmic and nuclear maturation of oocytes in mammals – living in the shadow of cells developmental capability

Abstract

The pig is a polyestrous animal in which the ovarian cycle lasts about 21 days and results in ovulation of 10-25 oocytes. Ovum reaches 120-150 μm in diameter, with the surrounding corona radiata providing communication with the environment. The zona pellucida is composed of glycoproteins: ZP1, ZP2, ZP3. In the course of oogenesis, RNA and protein accumulation for embryonic development occurs. Maternal mRNA is the template for protein production. Nuclear, cytoplasmic and genomic maturity condition the ability of the ovum to undergo fertilization. There are several differences in protein expression profiles observed between in vitro and in vivo conditions. Oogenesis is the process of differentiating female primary sex cells into gametes. During development gonocytes migrate from the yolk sac into the primary gonads with TGF-1, fibronectin, and laminin regulating this process. Cell cycle is blocked in dictyotene. Primary oocyte maturation is resumed before each ovulation and lasts until the next block in metaphase II. At the moment of penetration of the sperm into the ovum, the metaphase block is broken. The oocytes, surrounded by a single layer of granular cells, form the ovarian follicle. The exchange of signals between the oocyte and the cumulus cells done by gap-junctions, as well as various endo and paracrine signals. The contact between the corona radiata cells provides substances necessary for growth, through the same gap junctions. Studies on follicular cells can be used to amplify the knowledge of gene expression in these cells, in order to open way for potential clinical applications.

Open access