Differential expression of CCN-family members in primary human bone marrow-derived mesenchymal stem cells during osteogenic, chondrogenic and adipogenic differentiation

BACKGROUND: The human cysteine rich protein 61 (CYR61, CCN1) as well as the other members of the CCN family of genes play important roles in cellular processes such as proliferation, adhesion, migration and survival. These cellular events are of special importance within the complex cellular interactions ongoing in bone remodeling. Previously, we analyzed the role of CYR61/CCN1 as an extracellular signaling molecule in human osteoblasts. Since mesenchymal stem cells of bone marrow are important progenitors for various differentiation pathways in bone and possess increasing potential for regenerative medicine, here we aimed to analyze the expression of CCN family members in bone marrow-derived human mesenchymal stem cells and along the osteogenic, the adipogenic and the chondrogenic differentiation. RESULTS: Primary cultures of human mesenchymal stem cells were obtained from the femoral head of patients undergoing total hip arthroplasty. Differentiation into adipocytes and osteoblasts was done in monolayer culture, differentiation into chondrocytes was induced in high density cell pellet cultures. For either pathway, established differentiation markers and CCN-members were analyzed at the mRNA level by RT-PCR and the CYR61/CCN1 protein was analyzed by immunocytochemistry. RT-PCR and histochemical analysis revealed the appropriate phenotype of differentiated cells (Alizarin-red S, Oil Red O, Alcian blue, alkaline phosphatase; osteocalcin, collagen types I, II, IX, X, cbfa1, PPARγ, aggrecan). Mesenchymal stem cells expressed CYR61/CCN1, CTGF/CCN2, CTGF-L/WISP2/CCN5 and WISP3/CCN6. The CYR61/CCN1 expression decreased markedly during osteogenic differentiation, adipogenic differentiation and chondrogenic differentiation. These results were confirmed by immuncytochemical analyses. WISP2/CCN5 RNA expression declined during adipogenic differentiation and WISP3/CCN6 RNA expression was markedly reduced in chondrogenic differentiation. CONCLUSION: The decrease in CYR61/CCN1 expression during the differentiation pathways of mesenchymal stem cells into osteoblasts, adipocytes and chondrocytes suggests a specific role of CYR61/CCN1 for maintenance of the stem cell phenotype. The differential expression of CTGF/CCN2, WISP2/CCN5, WISP3/CCN6 and mainly CYR61/CCN1 indicates, that these members of the CCN-family might be important regulators for bone marrow-derived mesenchymal stem cells in the regulation of proliferation and initiation of specific differentiation pathways

Техническое обслуживание резервуарного парка перевалочной нефтебазы «Таманьнефтегаз»

Объектом исследования является резервуарный парк перевалочной нефтебазы «Таманьнефтегаз». Цель работы - разработка технического обслуживание резервуарного парка перевалочной нефтебазы «Таманьнефтегаз». В процессе исследования проводились анализ и расчет элементов конструкции резервуаров. В результате исследования разработана технология технического обслуживание резервуарного парка перевалочной нефтебазы «Таманьнефтегаз».The object of research is a transshipment tank farm tank farm "Tamanneftegas". The purpose of the work - the development of the technical service the tank farm transshipment tank farm "Tamanneftegas". The study carried out an analysis and calculation design elements reservoirs. The study developed a technology for the technical maintenance of the tank farm transshipment tank farm "Tamanneftegas". Degree of implementation: not yet available

In situ guided tissue regeneration in musculoskeletal diseases and aging: Implementing pathology into tailored tissue engineering strategies

In situ guided tissue regeneration, also addressed as in situ tissue engineering or endogenous regeneration, has a great potential for population-wide “minimal invasive” applications. During the last two decades, tissue engineering has been developed with remarkable in vitro and preclinical success but still the number of applications in clinical routine is extremely small. Moreover, the vision of population-wide applications of ex vivo tissue engineered constructs based on cells, growth and differentiation factors and scaffolds, must probably be deemed unrealistic for economic and regulation-related issues. Hence, the progress made in this respect will be mostly applicable to a fraction of post-traumatic or post-surgery situations such as big tissue defects due to tumor manifestation. Minimally invasive procedures would probably qualify for a broader application and ideally would only require off the shelf standardized products without cells. Such products should mimic the microenvironment of regenerating tissues and make use of the endogenous tissue regeneration capacities. Functionally, the chemotaxis of regenerative cells, their amplification as a transient amplifying pool and their concerted differentiation and remodeling should be addressed. This is especially important because the main target populations for such applications are the elderly and diseased. The quality of regenerative cells is impaired in such organisms and high levels of inhibitors also interfere with regeneration and healing. In metabolic bone diseases like osteoporosis, it is already known that antagonists for inhibitors such as activin and sclerostin enhance bone formation. Implementing such strategies into applications for in situ guided tissue regeneration should greatly enhance the efficacy of tailored procedures in the future

What drives banks' geographic expansion? the role of locally non-diversifiable risk

We show that banks that are facing relatively high locally non-diversifiable risks in their home region expand more across states than banks that do not face such risks following branching deregulation in the 1990s and 2000s. These banks with high locally non-diversifiable risks also benefit relatively more from deregulation in terms of higher bank stability. Further, these banks expand more into counties where risks are relatively high and positively correlated with risks in their home region, suggesting that they do not only diversify but also build on their expertise in local risks when they expand into new regions

How do banks react to catastrophic events? Evidence from hurricane Katrina

This paper explores how banks adjust their risk-based capital ratios and asset allocations following an exogenous shock to their asset quality caused by Hurricane Katrina in 2005. We find that independent banks based in the disaster areas increase their risk-based capital ratios after the hurricane, while those part of a bank holding company do not. The effect on independent banks mainly comes from the subgroup of high-capitalized banks. These banks increase their holdings in government securities and reduce loans to non-financial firms. Hence, banks that become more stable achieve this at the cost of reduced lending

How do insured deposits affect bank risk? Evidence from the 2008 Emergency Economic Stabilization Act : [version december 2013]

This paper tests whether an increase in insured deposits causes banks to become more risky. We use variation introduced by the U.S. Emergency Economic Stabilization Act in October 2008, which increased the deposit insurance coverage from $100,000 to$250,000 per depositor and bank. For some banks, the amount of insured deposits increased significantly; for others, it was a minor change. Our analysis shows that the more affected banks increase their investments in risky commercial real estate loans and become more risky relative to unaffected banks following the change. This effect is most distinct for affected banks that are low capitalized