Effects Of Human Wharton's Jelly Mesenchymal Stem Cells On In Vitro Functions Of Aged Mouse Clonogenic Cardiac Cells

Exposure of aged stem cells to young systemic environment has shown to improve their functions in vivo. While heart disease commonly affects elderly patients, it is unclear if biologically young Wharton’s jelly-derived mesenchymal stem cells (MSCs) can improve the functions of aged cardiac c-kit cells (CCs) in vitro. This study examined the effects of MSCs on the functions of aged CCs. CCs were isolated from 1- and 18-month-old C57BL/6N mice and were co-cultured with human MSCs with direct cell-cell contact or separated with a Transwell insert. Stemness, growth kinetics, relative telomere length and telomerase activity of the aged CCs were evaluated in comparison with both young (yCCs) and aged CCs (aCCs) without MSC co-culture. To test the effects of extracellular matrices (ECM) produced from MSCs, CCs were cultured on ECM-derived from MSCs treated with cardiogenic medium. Proliferation and oxidative stress assays were performed to evaluate the effect of MSC-derived ECM on CCs. All data were analysed using ANOVA. The primary aCCs showed significantly lower clonogenicity compared to yCCs (9.5 ± 2.9% vs. 21.2 ± 4.4%; p < 0.05). Following clonogenic expansion, only CD90PosCD140aPosCD166Neg cells were expanded in the aCCs, which were different from the phenotype of yCCs (CD90NegCD140aNegCD166Pos) as assessed by flow cytometry. Clonogenic aCCs showed comparable telomere length to yCCs. However, these cells showed lower Gata4, Nkx2.5 and Sox2 gene expressions, with changes of 2.4, 3767.0, 4.9 folds, respectively. These cells presented a lower sphere formation capability (4 ± 1 vs. 64 ± 19 spheres; p < 0.05) and did not spontaneously differentiate into cardiomyocyte and endothelial lineage. Direct co-culture of both cells increased aCC migration which repopulated 54.6 ± 4.4% of the gap area as compared to aCCs with MSCs in Transwell (42.9 ± 2.6%) and aCCs without MSCs (44.7 ± 2.5%, p < 0.05)

Glial cell line-drived neurotrophic factor (GDNF) family of ligands is a mitogenic agent in human glioblastoma and confers chemoresistance in a ligand-specific fashion

Ph.DDOCTOR OF MEDICIN

Cardiac Stem Cells for Myocardial Regeneration: They Are Not Alone

Heart failure is the number one killer worldwide with ~50% of patients dying within 5 years of prognosis. The discovery of stem cells, which are capable of repairing the damaged portion of the heart, has created a field of cardiac regenerative medicine, which explores various types of stem cells, either autologous or endogenous, in the hope of finding the “holy grail” stem cell candidate to slow down and reverse the disease progression. However, there are many challenges that need to be overcome in the search of such a cell candidate. The ideal cells have to survive the harsh infarcted environment, retain their phenotype upon administration, and engraft and be activated to initiate repair and regeneration in vivo. Early bench and bedside experiments mostly focused on bone marrow-derived cells; however, heart regeneration requires multiple coordinations and interactions between various cell types and the extracellular matrix to form new cardiomyocytes and vasculature. There is an observed trend that when more than one cell is coadministered and cotransplanted into infarcted animal models the degree of regeneration is enhanced, when compared to single-cell administration. This review focuses on stem cell candidates, which have also been tested in human trials, and summarizes findings that explore the interactions between various stem cells in heart regenerative therapy

Human wharton’s jelly-derived mesenchymal stem cells minimally improve the growth kinetics and cardiomyocyte differentiation of aged murine cardiac c-kit cells in in vitro without rejuvenating effect

Cardiac c-kit cells show promise in regenerating an injured heart. While heart disease commonly affects elderly patients, it is unclear if autologous cardiac c-kit cells are functionally competent and applicable to these patients. This study characterised cardiac c-kit cells (CCs) from aged mice and studied the effects of human Wharton’s Jelly-derived mesenchymal stem cells (MSCs) on the growth kinetics and cardiac differentiation of aged CCs in vitro. CCs were isolated from 4-week- and 18-month-old C57/BL6N mice and were directly co-cultured with MSCs or separated by transwell insert. Clonogenically expanded aged CCs showed comparable telomere length to young CCs. However, these cells showed lower Gata4, Nkx2.5, and Sox2 gene expressions, with changes of 2.4, 3767.0, and 4.9 folds, respectively. Direct co-culture of both cells increased aged CC migration, which repopulated 54.6 ± 4.4% of the gap area as compared to aged CCs with MSCs in transwell (42.9 ± 2.6%) and CCs without MSCs (44.7 ± 2.5%). Both direct and transwell co-culture improved proliferation in aged CCs by 15.0% and 16.4%, respectively, as traced using carboxyfluorescein succinimidyl ester (CFSE) for three days. These data suggest that MSCs can improve the growth kinetics of aged CCs. CCs retaining intact telomere are present in old hearts and could be obtained based on their self-renewing capability. Although these aged CCs with reduced growth kinetics are improved by MSCs via cell–cell contact, the effect is minimal

Investigation On Process-Properties Relationship With Mechanical Properties Of Lattice-Structured Cellular Material For Lightweight Application

Lattice structures possess exceptional mechanical strength resulting in highly efficient load supporting systems. The lattice structure has been receiving interest in a variety of application areas and industries such as automotive, shipping and aeronautic. The metallic or polymer micro lattice structure can be categorized as lightweight and energy-absorbing structure. These characteristics are best applied to transportation part where the lightweight structure will help reduce its overall weight, thus increase the operational time since energy and cost consumption is a big concern in the industry these days. The aim of this study is to investigate relationship between process-properties and mechanical performance of polymer lattice structure. The lattice structure was designed by using SolidWorks software and fabricated using CubePro 3D printing machine. Compression test was performed by Instron 5585 universal testing machine to analyse the strength of the lattice structure. It was found that lattice structure manufactured with the setting of solid print strength, honeycomb print pattern, 70 µm layer thickness and strut diameter of 2.4 mm possesses the optimum mechanical property

Conditioned Medium of Human Menstrual Blood-Derived Endometrial Stem Cells Protects Against MPP+-Induced Cytotoxicity in vitro

Mesenchymal stem cells (MSCs) showed the potential to treat Parkinson’s disease (PD). However, it is unknown whether the conditioned medium of human menstrual blood-derived endometrial stem cells (MenSCs-CM) has the function to alleviate syndromes of PD. In this study, human neuroblastoma SH-SY5Y cells were exposed to neurotoxicant 1-methyl-4-phenylpyridinium (MPP+) for inducing a range of response characteristics of PD. After culturing this cell model with 24 h/48 h collected MenSCs-CM for different days, cell viability, pro-inflammation cytokines, mitochondrial membrane potential (ΔΨm), oxidative stress, and cell apoptosis were detected. Finally, protein assay was performed to detect 12 kinds of neurotrophic factors inside MenSCs-CM. Our results showed that MPP+ caused SH-SY5Y cell viability reduction as an increasing dose and time dependent manner. MPP+ treatment resulted in inflammation, mitochondrial dysfunction, reactive oxygen species (ROS) production accumulation, and apoptosis of SH-SY5Y at its IC50 concentration. Forty-eight hours-collected MenSCs-CM and culturing with the MPP+-treated SH-SY5Y for 2 days are the optimized condition to increase cell viability. Besides, MenSCs-CM was efficacious against MPP+ induced inflammation, ΔΨm loss, ROS generation, and it could significantly decrease cells numbers in late apoptosis stage. What’s more, protein assay showed that MenSCs-CM contained various neuroprotective factors. Our study provided the first evidence that MenSCs-CM has a protective effect on MPP+-induced cytotoxicity in various aspects, and firstly showed that MenSCs can release at least 12 kinds of neurotrophic factors to medium, which may contribute to the protective function of MenSCs-CM to treat PD. This research enlightening that MenSCs-CM is beneficial in the therapy for PD and probably also for other neurodegenerative diseases

Cryopreservation of Neurospheres Derived from Human Glioblastoma Multiforme

Cancer stem cells have been shown to initiate and sustain tumor growth. In many instances, clinical material is limited, compounded by a lack of methods to preserve such cells at convenient time points. Although brain tumor-initiating cells grown in a spheroid manner have been shown to maintain their integrity through serial transplantation in immune-compromised animals, practically, it is not always possible to have access to animals of suitable ages to continuously maintain these cells. We therefore explored vitrification as a cryopreservation technique for brain tumor-initiating cells. Tumor neurospheres were derived from five patients with glioblastoma multiforme (GBM). Cryopreservation in 90% serum and 10% dimethyl sulfoxide yielded greatest viability and could be explored in future studies. Vitrification yielded cells that maintained self-renewal and multipotentiality properties. Karyotypic analyses confirmed the presence of GBM hallmarks. Upon implantation into NOD/SCID mice, our vitrified cells reformed glioma masses that could be serially transplanted. Transcriptome analysis showed that the vitrified and nonvitrified samples in either the stem-like or differentiated states clustered together, providing evidence that vitrification does not change the genotype of frozen cells. Upon induction of differentiation, the transcriptomes of vitrified cells associated with the original primary tumors, indicating that tumor stem-like cells are a genetically distinct population from the differentiated mass, underscoring the importance of working with the relevant tumor-initiating population. Our results demonstrate that vitrification of brain tumor-initiating cells preserves the biological phenotype and genetic profiles of the cells. This should facilitate the establishment of a repository of tumor-initiating cells for subsequent experimental designs

Dominância fiscal : uma investigação empírica sobre o caso brasileiro no período de 2003 a 2014

A estabilização econômica dos anos de 1990 e a adoção do tripé econômico, a partir de 1999, marcam o fim de um capítulo delicado da história brasileira; a partir de então, era necessária a existência de certa sintonia de políticas monetária e fiscal para a manutenção do controle dos diversos indicadores econômicos. Contudo, com essa reciprocidade na política econômica, são incitadas discussões sobre a orientação do governo na hora de definir suas prioridades nesse campo: as variáveis fiscais são priorizadas e, por conseguinte, determinadas, forçando as monetárias a se ajustarem – ou o contrário? A resposta para esse questionamento leva à discussão sobre a dominância fiscal. Assim, esse trabalho visa verificar empiricamente, usando das modelagens econométricas VAR e estudo de eventos, se há dominância fiscal ou monetária na economia brasileira e se a eficácia da política monetária mudou na transição do governo Lula para o governo Dilma. O resultado foi inconclusivo para o governo Lula e indicou dominância fiscal no governo Dilma. Ainda verificou-se não haver modificação na eficácia da política monetária.Economic stabilization, in the 1990s, and utilization of an economic tripod, after 1999, represents the end of a delicate chapter in Brazilian history. Ever since, it was necessary the existence of a certain agreement between monetary and fiscal politic, in order to maintain under control a variety of economic indicators. However, this reciprocity (in economic politic) starts discussions about the real government orientations when it comes to define its priority on this subject: are the fiscal variables priorized, and then, determined, forcing monetary variables to adjust themselves, or the opposite? The answer to these questions emerge from the fiscal dominance discussion. This paper intends to empiric verify, using econometric modeling VAR and event study, if there is fiscal dominance or monetary in Brazilian economy and whether the effectiveness of monetary politic has changed in the transition from Lula's government to the Dilma government. The result was inconclusive for the Lula government and indicated fiscal dominance in the Dilma government. There was still no change in the efficiency of the monetary politic.CAPE

Serum and plasma myeloperoxidase in acute coronary syndrome and chronic stable angina

Myeloperoxidase (MPO) plays essential roles in the pathogenesis of coronary plaque destabilization. This case-control study aimed to investigate the differences in EDTAplasma MPO level in acute coronary syndrome (ACS) and chronic stable angina (CSA). This study also aimed to investigate the differences in the MPO levels in serum and EDTAplasma samples among ACS and CSA patients. Cases involved 9 ACS patients (age 52.8±11.9 years; mean±S.D.) who underwent primary angioplasty, while 9 CSA patients (age 58.3±11.4 years; mean±S.D.) were recruited as controls. The MPO was measured in EDT A-plasma and matched serum samples collected from femoral artery, antecubital vein and at the culprit coronary artery using in-house developed and validated sandwich ELISA. C-reactive protein (CRP) served as reference protein. Serum MPO level was significantly higher compared to EDTA-plasma in ACS and CSA. For ACS, the MPO level (mean±SD) in serum was significantly higher in venous blood (2864.64±1777.40 ng/ml vs. 1321.31±319 .02 ng/ml, p=0.021) and intracoronary blood (2949 .31±2170.21 ng/ml vs. 1230.08±383.85 ng/ml, p=0.033) compared to EDTA-plasma. However, there was no significant difference (p=0.171) between serum and EDTA-plasma MPO level for blood taken from femoral artery. For CSA, there were significant differences between serum and EDTA-plasma MPO level in femoral arterial blood (2521.29±1266.97 ng/ml vs. 549 .65±526.09 ng/ml, p=0.001 ), antecubital venous blood (2171.25±983 .27 ng/ml vs. 725.27±671.56 ng/ml, p=0.004) and intracoronary arterial blood (1979.59±912.41 ng/ml vs. 621.00±528.93 ng/ml, p=0.001). The EDTA-plasma MPO concentration was significantly higher in ACS compared to CSA for blood sampled from femoral artery (1259.19±405.49 ng/ml vs. 549.65±526.09 ng/ml, p=0.005), antecubital vein (1321.31±319.02 ng/ml vs. 725.27±671.56 ng/ml, p=0.031) and intracoronary artery (1321.31±319.02 ng/ml vs. 725.27±671.56 ng/ml, p=0.013). There was however no significant association between MPO and CRP concentration in ACS and CSA. These findings suggest that MPO concentration in EDTA-plasma were dissonant with those measured in matched serum samples. The EDT A-plasma is the preferred specimen for MPO measurement as its value is not confounded by poorly controllable ex vivo release of MPO from leucocytes as in serum. This study also shows that EDT A-plasma MPO is significantly higher in patients with ACS compared with CSA patients. These findings suggest a potential role of MPO as a marker of atheromatous plaque growth and wlnerability. Large cohort studies are required to establish the clinical importance and pathogenic significance of MPO in plaque destabilization