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Full-Text Articles in Life Sciences

Epigenetics: The Guardian Of Pluripotency And Differentiation, Marta Gladych, Aleksandra Nijak, Paula Lota, Urszula Oleksiewicz Jan 2016

Epigenetics: The Guardian Of Pluripotency And Differentiation, Marta Gladych, Aleksandra Nijak, Paula Lota, Urszula Oleksiewicz

Turkish Journal of Biology

Multicellular organisms comprise a variety of cell types that have the same genotype but distinct phenotypes. This diversity is possible because of the establishment of a specific epigenetic landscape that stabilizes gene expression profiles that are exclusive for a particular cell type. Accumulating data indicate that the maintenance, loss, and reacquisition of pluripotency are dynamically regulated by epigenetic alterations evoked by a subset of cellular factors. A better understanding of the epigenetic mechanisms involved in stem cell biology and differentiation will improve our ability to use these cells in the clinical context. Here we review current insights into the epigenetic …


Pluripotent Stem Cells And Their Use In Hearing Loss, Ahmet Hamdi̇ Kepekçi̇, Okan Özgür Özturan, Mustafa Yavuz Köker Jan 2016

Pluripotent Stem Cells And Their Use In Hearing Loss, Ahmet Hamdi̇ Kepekçi̇, Okan Özgür Özturan, Mustafa Yavuz Köker

Turkish Journal of Biology

Throughout its half a century of development, stem cell research has included two main fields: embryonic stem (ES) cell research and the reprogramming of body somatic cells. In the present review we focused on stem cell reprogramming and its relation with otolaryngology. The human body somatic cells are transformed into pluripotent cells by three basic methods: the somatic nuclear transfer method, the somatic cell fusion method (getting cellular pluripotent capacity in cellular reprogramming), and by transcription factors influencing the body somatic cells to generate reprogrammed induced pluripotent stem (iPS) cells. ES cells and iPS cells have pluripotency and differentiate into …


Epigenetic Regulation Of Specific Transcription Factors In Osteogenicdifferentiation Of Mesenchymal Stem Cells, Milad Zadi Heydarabad, Mousa Vatanmakanian, Mina Nikasa, Majid Farshdousti Hagh Jan 2016

Epigenetic Regulation Of Specific Transcription Factors In Osteogenicdifferentiation Of Mesenchymal Stem Cells, Milad Zadi Heydarabad, Mousa Vatanmakanian, Mina Nikasa, Majid Farshdousti Hagh

Turkish Journal of Biology

An abundance of experiments have been performed to clarify the differentiation process of mesenchymal stem cells (MSCs). Osteogenic differentiation and in vitro conditions favoring these cell lineages have attracted the attention of many researchers. Moreover, the gene expression profile during MSC differentiation toward its main specialized cells (bone, cartilage, and adipose cells) has been mostly understood. In the last decades another layer of investigation has attempted to clarify the epigenetic mechanisms underlying MSC differentiation into its specialized cells. It has been shown that as MSCs progress through the differentiation process, more nonspecific genes undergo DNA methylation to prevent differentiation into …


Limbal Stem Cell Deficiency: Special Focus On Tracking Limbal Stem Cells, Santhosh Kacham, Bhaskar Birru, Sreenivasa Rao Parcha, Ramaraju Baadhe Jan 2016

Limbal Stem Cell Deficiency: Special Focus On Tracking Limbal Stem Cells, Santhosh Kacham, Bhaskar Birru, Sreenivasa Rao Parcha, Ramaraju Baadhe

Turkish Journal of Biology

The cornea, the transparent part of the eye that helps in the formation of images, has multiple layers. Among them, the superficial epithelial layer is protected and maintained homeostatically by the limbus, located in the periphery of the cornea. Limbal stem cells are located at the basal layer of the limbus and the loss of these cells is called limbal stem cell deficiency (LSCD). LSCD is characterized by corneal vascularization, inflammation, and conjunctivalization, which ultimately lead to blindness. Several clinical transplantation procedures used for the treatment of LSCD are cultivated limbal epithelial transplantation, simple limbal epithelial transplantation, and cultured oral …


Comparison Of Enzymatic And Nonenzymatic Isolation Methods For Endometrial Stem Cells, Polen Koçak, Serli̇ Cani̇kyan, Meli̇ke Batukan, Rukset Attar, Fi̇kretti̇n Şahi̇n, Di̇lek Telci̇ Jan 2016

Comparison Of Enzymatic And Nonenzymatic Isolation Methods For Endometrial Stem Cells, Polen Koçak, Serli̇ Cani̇kyan, Meli̇ke Batukan, Rukset Attar, Fi̇kretti̇n Şahi̇n, Di̇lek Telci̇

Turkish Journal of Biology

Human endometrial stem cells (hESCs) are mesenchymal stem cells, which are responsible for the monthly renewal of the basal layer of the human endometrium by facilitating stromal and vascular regeneration. In this study, hESCs were isolated by using three different isolation methods including nonenzymatic and enzymatic digestion with trypsin and collagenase type 1. To determine the efficiency of these three methods, cells were characterized using a cell proliferation assay and mesenchymal and hematopoietic stem cell markers. Our results demonstrate that although the nonenzymatic isolation method gave rise to hESCs that had a higher proliferative rate, the mesenchymal stem cell profiles …


Comparison Of The Osteogenic Differentiation Capacity Of Adipose Tissuederived Mesenchymal Stem Cells From Humans And Rats, Seçi̇l Erden Tayhan, Şeyma Taşdemi̇r, Sai̇me İsmet Deli̇loğlu Gürhan, Erol Mi̇r Jan 2016

Comparison Of The Osteogenic Differentiation Capacity Of Adipose Tissuederived Mesenchymal Stem Cells From Humans And Rats, Seçi̇l Erden Tayhan, Şeyma Taşdemi̇r, Sai̇me İsmet Deli̇loğlu Gürhan, Erol Mi̇r

Turkish Journal of Biology

Mesenchymal stem cells (MSCs) can be found in many types of adult tissues such as the bone marrow, adipose, placenta, liver, and periosteum. Recently, adipose tissue-derived MSCs (ADMSCs) have become one the most preferred MSC types because of their fast proliferation rate, abundance, and high plasticity for variable cell types. It is known that ADMSCs are able to differentiate into various cells, including osteoblasts, so they are quite promising for orthopedic clinical trials. The present study aimed to compare the osteogenic differentiation conditions of MSCs from human adipose tissue (hADMSC) and those of MSCs from rat adipose tissue (rADMSC). Therefore, …


Analysis Of Global Micrornaome Profiles Of Caenorhabditis Elegans Oocytes And Early Embryos, Selen Güçlü Durgun, Ahmet Raşi̇t Öztürk, Arzu Atalay Jan 2016

Analysis Of Global Micrornaome Profiles Of Caenorhabditis Elegans Oocytes And Early Embryos, Selen Güçlü Durgun, Ahmet Raşi̇t Öztürk, Arzu Atalay

Turkish Journal of Biology

One of the most complex cell transformations in biology is the remodeling of a fertilized oocyte into a totipotent zygote. There is no transcription during this event, and therefore mRNAs and proteins accumulated in the oocyte during oogenesis are utilized until zygotic genome activation. In order to differentiate into somatic cells, the embryo must erase the totipotency signature coming from the oocyte cytoplasm in the somatic blastomeres. In this study, the microRNAome profiles of oocytes and early embryos before and after zygotic genome activation were identified. By using next-generation high-throughput pyrosequencing and miRNA microarray techniques, miRNAome profiles of Caenorhabditis elegans …


Human Adipose-Derived Stem Cells Differentiation Into Epidermal Cells And Interaction With Human Keratinocytes In Coculture, Alexandra Gaspar, Daniel Constantin, Ana-Maria Seciu, Lucia Moldovan, Oana Craciunescu, Elena Ganea Jan 2016

Human Adipose-Derived Stem Cells Differentiation Into Epidermal Cells And Interaction With Human Keratinocytes In Coculture, Alexandra Gaspar, Daniel Constantin, Ana-Maria Seciu, Lucia Moldovan, Oana Craciunescu, Elena Ganea

Turkish Journal of Biology

Current procedures used for skin injury reepithelization have yet to improve. At present, stem cell-based therapies provide great potential in repairing different damaged tissues due to the multipotent character of these cells. This study aimed to investigate the in vitro differentiation capacity of human adipose-derived stem cells (ASCs) into epidermal cells and to evaluate their interaction with HaCaT keratinocytes in coculture experimental models that mimicked the living environment of human skin. The mesenchymal phenotype of isolated stem cells was indicated by their spindle-shaped morphology and the expression of specific surface markers CD73, CD90, and CD105. After 21 days of cultivation …


Baculoviral Vector Loaded Mesenchymal Stem Cells As Efficient Gene Therapy Tools For Cancer Treatment, Sedef Hande Aktaş, Hakan Akbulut, Ayşe Eser Elçi̇n, Mahmut Parmaksiz, Arzu Keski̇n Aktan, Arzu Çöleri̇ Ci̇han, Yaşar Murat Elçi̇n, Fi̇kri̇ İçli̇ Jan 2016

Baculoviral Vector Loaded Mesenchymal Stem Cells As Efficient Gene Therapy Tools For Cancer Treatment, Sedef Hande Aktaş, Hakan Akbulut, Ayşe Eser Elçi̇n, Mahmut Parmaksiz, Arzu Keski̇n Aktan, Arzu Çöleri̇ Ci̇han, Yaşar Murat Elçi̇n, Fi̇kri̇ İçli̇

Turkish Journal of Biology

Insufficient targeting of the therapeutic genes to tumor cells is one of the major reasons for failure in cancer gene therapy. Mesenchymal stem cells (MSCs) seem to be a good candidate as a carrier for gene therapy because of its selective tumor tissue-homing properties. In the current study, we constructed baculoviral vectors (BVs) carrying cytosine deaminase (CD) (BV-CD) or green fluorescence protein (GFP) genes (BV-GFP) and tested the transduction efficiency of the vectors in tumor and mesenchymal stem cells. We also tested the in vivo efficacy of the BV-CD vector in a colon cancer model. Our results showed that the …


The Heart Of The Matter: Cardiac Stem Cells, Esra Çağavi̇, Arzuhan Koç, Sevi̇lay Şahoğlu Göktaş Jan 2016

The Heart Of The Matter: Cardiac Stem Cells, Esra Çağavi̇, Arzuhan Koç, Sevi̇lay Şahoğlu Göktaş

Turkish Journal of Biology

Cardiovascular diseases are the primary cause of death in the world. Pharmacological and surgical approaches are the main treatment options for heart disease; however, heart transplantation may be the only option for advanced heart failure patients despite its limited nature. Recent advances enabled stem cell-based therapies to become a promising treatment approach for injured or weakened cardiac tissue. With the identification of resident and heart-specific stem cells in early 2000, new avenues of research have been opened to understand heart development, disease, and regeneration. In this review article, different cardiac stem cell subpopulations are classified and defined based on the …


Epigenetic Regulation Of Brca1 Expression And Its Role Inbreast Cancer Stem Cell Development, Elena Shestakova Jan 2016

Epigenetic Regulation Of Brca1 Expression And Its Role Inbreast Cancer Stem Cell Development, Elena Shestakova

Turkish Journal of Biology

The tumor suppressor breast cancer 1, early onset (BRCA1) plays an important role in maintaining the genome integrity, actively participating in DNA repair via homologous recombination. The level of functional final BRCA1 protein is precisely regulated in cells. Epigenetic regulation of BRCA1 gene expression is one of the most important mechanisms for BRCA1 level fine-tuning. In this review the main epigenetic mechanisms of BRCA1 expression regulation are presented, including DNA methylation, histone covalent modifications, and regulation with transcription factors. Another important function of BRCA1 emerging in recent years is its role in the regulation of breast cancer stem cell development. …


Cancer Stem Cells: Lessons Learned From The Leukemic Stem Cells, Ayten Kandi̇lci̇ Jan 2016

Cancer Stem Cells: Lessons Learned From The Leukemic Stem Cells, Ayten Kandi̇lci̇

Turkish Journal of Biology

Cancer is the second cause of death in Turkey and the frequency of cancer deaths increased from 12% in 2002 to 21% in 2009 ( Özkan et al., 2013). To win the war on cancer, we certainly need to apply well-planned prevention policies, given that it is caused mostly by environmental factors, and to develop more effective therapies. To achieve a cure for the disease, it is crucial to understand the cellular and molecular mechanisms leading to cancer and to therapeutically target all the factors playing a role in the initiation, progression, maintenance, and relapse of the disease, preferably in …


Myelin Disorders And Stem Cells: As Therapies And Models, Fatmagül İlayda Aydinli, Eşref Çeli̇k, Burcu Kurt Vatandaşlar, Bi̇lal Ersen Kerman Jan 2016

Myelin Disorders And Stem Cells: As Therapies And Models, Fatmagül İlayda Aydinli, Eşref Çeli̇k, Burcu Kurt Vatandaşlar, Bi̇lal Ersen Kerman

Turkish Journal of Biology

Myelin disorders burden millions of people around the world, yet existing therapies are inadequate to cure them. Current remedies commonly treat the symptoms with minimal to no effect on the actual cause of the disorder. The basis and/or the mechanism of demyelination is not known for many of the disorders either. In recent years, stem cells of variable origin have been used in clinical trials as transplant agents to restore the defective biochemical process or the damaged tissue. We summarize the outcomes of these trials for demyelination disorders. The capability of reprograming mature cells into stem cells equips researchers with …