|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | The California stem cell agency is proposing an $18.5 million operational budget for the coming fiscal year that will include a more than 12 percent increase in staff and reflect the rising costs of monitoring more than 400 grants and loans.
The agency did not disclose the size of the increase for the spending plan compared to actual spending projected through the end of the current fiscal | | | | | | | | | | | | | | | | | | | | | | | | A key group of directors of the California stem cell agency will meet
Tuesday behind closed doors to discuss candidates to succeed Robert Klein as chairman of the $3 billion research effort.
The Governance Subcommittee has scheduled the session although it does not have any official candidates for the post. Only four state officials – the governor, treasurer, controller and lieutenant governor | | | | | | | | | | | | | | | | | | | | | | | | | Chemical control of stem cell fate and developmental potential. Angew Chem Int Ed Engl. 2011 Jan 3;50(1):200-42 Authors: Lyssiotis CA, Lairson LL, Boitano AE, Wurdak H, Zhu S, Schultz PG Potential applications of stem cells in medicine range from their inclusion in disease modeling and drug discovery to cell transplantation and regenerative therapies. However, before this promise can be realized several obstacles must be overcome, including the control of stem cell differentiation, allogeneic rejection and limited cell availability. This will require an improved understanding of the mechanisms that govern stem cell potential and the development of robust methods to efficiently control their fate. Recently, a number of small molecules have been identified that can be used both in vitro and in vivo as tools to expand stem cells, direct their differentiation, or reprogram somatic cells to a more naive state. These molecules have provided a wealth of insights into the signaling and epigenetic mechanisms that regulate stem cell biology, and are already beginning to contribute to the development of effective treatments for tissue repair and regeneration. PMID: 21184400 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | lines and bowl affect the specification of cyst stem cells and niche cells in the Drosophila testis. Development. 2011 May;138(9):1687-96 Authors: Dinardo S, Okegbe T, Wingert L, Freilich S, Terry N To function properly, tissue-specific stem cells must reside in a niche. The Drosophila testis niche is one of few niches studied in vivo. Here, a single niche, comprising ten hub cells, maintains both germline stem cells (GSC) and somatic stem cells (CySC). Here, we show that lines is an essential CySC factor. Surprisingly, lines-depleted CySCs adopted several characteristics of hub cells, including the recruitment of new CySCs. This led us to examine the developmental relationship between CySCs and hub cells. In contrast to a previous report, we did not observe significant conversion of steady-state CySC progeny to hub fate. However, we found that these two cell types derive from a common precursor pool during gonadogenesis. Furthermore, lines mutant embryos exhibited gonads containing excess hub cells, indicating that lines represses hub cell fate during gonadogenesis. In many tissues, lines acts antagonistically to bowl, and we found that this is true for hub specification, establishing bowl as a positively acting factor in the development of the testis niche. PMID: 21486923 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Application of carbon fibers to biomaterials: A new era of nano-level control of carbon fibers after 30-years of development. Chem Soc Rev. 2011 Apr 13; Authors: Saito N, Aoki K, Usui Y, Shimizu M, Hara K, Narita N, Ogihara N, Nakamura K, Ishigaki N, Kato H, Haniu H, Taruta S, Ahm Kim Y, Endo M Carbon fibers are state-of-the-art materials with properties that include being light weight, high strength, and chemically stable, and are applied in various fields including aeronautical science and space science. Investigation of applications of carbon fibers to biomaterials was started 30 or more years ago, and various products have been developed. Because the latest technological progress has realized nano-level control of carbon fibers, applications to biomaterials have also progressed to the age of nano-size. Carbon fibers with diameters in the nano-scale (carbon nanofibers) dramatically improve the functions of conventional biomaterials and make the development of new composite materials possible. Carbon nanofibers also open possibilities for new applications in regenerative medicine and cancer treatment. The first three-dimensional constructions with carbon nanofibers have been realized, and it has been found that the materials could be used as excellent scaffolding for bone tissue regeneration. In this critical review, we summarize the history of carbon fiber application to the biomaterials and describe future perspectives in the new age of nano-level control of carbon fibers (122 references). PMID: 21487627 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Recipes and mechanisms of cellular reprogramming: a case study on budding yeast Saccharomyces cerevisiae. BMC Syst Biol. 2011 Apr 12;5(1):50 Authors: Ding S, Wang W ABSTRACT: BACKGROUND: Generation of induced pluripotent stem cells (iPSCs) and converting one cell type to another (transdifferentiation) by manipulating the expression of a small number of genes highlight the progress of cellular reprogramming, which holds great promise for regenerative medicine. A key challenge is to find the recipes of perturbing genes to achieve successful reprogramming such that the reprogrammed cells function in the same way as the natural cells. RESULTS: We present here a systems biology approach that allows systematic search for effective reprogramming recipes and monitoring the reprogramming progress to uncover the underlying mechanisms. Using budding yeast as a model system, we have curated a genetic network regulating cell cycle and sporulation. Phenotypic consequences of perturbations can be predicted from the network without any prior knowledge, which makes it possible to computationally reprogram cell fate. As the heterogeneity of natural cells is important in many biological processes, we find that the extent of this heterogeneity restored by the reprogrammed cells varies significantly upon reprogramming recipes. The heterogeneity difference between the reprogrammed and natural cells may have functional consequences. CONCLUSIONS: Our study reveals that cellular reprogramming can be achieved by many different perturbations and the reprogrammability of a cell depends on the heterogeneity of the original cell state. We provide a general framework that can help discover new recipes for cellular reprogramming in human. PMID: 21486480 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Regenerative Medicine for Stroke - Are We There Yet? Cerebrovasc Dis. 2011 Apr 12;31(6):544-551 Authors: Onteniente B, Polentes J With the development of stem cell (SC) biology, cell-based therapy has become a highly challenging field for experimental and clinical research. Among neurological disorders, stroke has pioneered the clinical application of SC. Safety concerns have prevailed for pilot clinical studies and important preclinical work is ongoing to help SC therapy reach the level of generalization. Stroke is classically divided into an acute, a subacute and a chronic phase. Each phase is defined by a complex array of events with overlapping and distinct kinetics that lead to both rapid tissue degeneration and long-lasting remodeling. Each SC type possesses intrinsic properties - transposed via cell-autonomous and non-cell-autonomous signaling - that would more specifically address some of these events. A better definition of what is expected from SC therapy in stroke might help assign SC sources to the acute or chronic phases and possibly optimize their use in the clinic. PMID: 21487218 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Chemical control of stem cell fate and developmental potential. Angew Chem Int Ed Engl. 2011 Jan 3;50(1):200-42 Authors: Lyssiotis CA, Lairson LL, Boitano AE, Wurdak H, Zhu S, Schultz PG Potential applications of stem cells in medicine range from their inclusion in disease modeling and drug discovery to cell transplantation and regenerative therapies. However, before this promise can be realized several obstacles must be overcome, including the control of stem cell differentiation, allogeneic rejection and limited cell availability. This will require an improved understanding of the mechanisms that govern stem cell potential and the development of robust methods to efficiently control their fate. Recently, a number of small molecules have been identified that can be used both in vitro and in vivo as tools to expand stem cells, direct their differentiation, or reprogram somatic cells to a more naive state. These molecules have provided a wealth of insights into the signaling and epigenetic mechanisms that regulate stem cell biology, and are already beginning to contribute to the development of effective treatments for tissue repair and regeneration. PMID: 21184400 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Diffusion of dimethyl sulfoxide in tissue engineered collagen scaffolds visualized by computer tomography. Cryo Letters. 2010 Nov-Dec;31(6):493-503 Authors: Bernemann I, Manuchehrabadi N, Spindler R, Choi J, Wolkers WF, Bischof JC, Glasmacher B Cryopreservation is a convenient method for long-term preservation of natural and engineered tissues in regenerative medicine. Homogeneous loading of tissues with CPAs, however, forms one of the major hurdles in tissue cryopreservation. In this study, computer tomography (CT) as a non-invasive imaging method was used to determine the effective diffusion of Me2SO in tissue-engineered collagen scaffolds. The dimensions of the scaffolds were 30 x 30 x 10 mm3 with a homogeneous pore size of 100 microm and a porosity of 98%. CT images were acquired after equilibrating the scaffolds in phosphate buffered saline (PBS) and transferring them directly in 10% (v/v)Me2SO. The Me2SO loading process of the scaffold could thus be measured and visualized in real time. The experimental data were fitted using a diffusion equation. The calculated effective diffusion constant for Me2SO in the PBS loaded scaffold was determined from experimental diffusion studies to be 2.4 x 10(-6) cm2/s at 20 degrees C. PMID: 21410018 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Interaction of collagen with carbon nanotube: a molecular dynamics investigation. J Biomed Nanotechnol. 2011 Feb;7(1):186-7 Authors: Gopalakrishnan R, Subramanian V In variety of biological applications carbon nano materials interact with different biological macromolecules, such as proteins, carbohydrates and nucleic acids. In this study carbon nanotube (CNT) has been used as the model for carbon nanomaterials. Since, collagen is a large protein; model collagen like peptide (CPs) has been used to understand the interaction between CNT and collagen. Molecular dynamics (MD) simulation showed that the hydrophobic-hydrophobic interaction of the CNT-CPs play a crucial role in attracting the CPs towards the CNT. No structural aberrations occured in collagen upon interaction with CNT and hence CNT can be employed in the tissue engineering applications. PMID: 21485863 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Ultra-Rapid Purification of Collagen Type I for Tissue Engineering Applications. Tissue Eng Part C Methods. 2011 Apr 13; Authors: Pacak CA, Powers JM, Cowan DB Acid-solubilized collagen type I (COL1) can form highly-organized, three-dimensional (3-D) scaffolds for a wide variety of bioengineering and cell culture applications. A rapid COL1 isolation method would be a valuable tool for both basic and translational researchers because conventional techniques require days or weeks to complete, typically use non-human animal tissues as a source material, and do not efficiently purify autologous COL1 from small samples. Here, we describe a 3 hour method to isolate COL1 from rabbit, lamb, and human skin in sufficient quantities for fabrication of autologously-derived tissues by using a rapid agitation technique and incorporating centrifugal filtration units into a traditional isolation procedure. We demonstrate that the purified product is comparable to traditional preparations using polyacrylamide gel electrophoresis, transmission electron microscopy, and collagen content assays. In addition, our COL1 is able to support myogenic cell growth and direct orientation of these cells in vitro. Importantly, this ultra-rapid COL1 isolation procedure increases the feasibility of autologous COL1 use in humans as well as over-all safety for clinical patients. PMID: 21486201 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Co-culture of chondrocytes and bone marrow mesenchymal stem cells in vitro enhances the expression of cartilaginous extracellular matrix components. Braz J Med Biol Res. 2011 Apr;44(4):303-10 Authors: Qing C, Wei-Ding C, Wei-Min F Chondrocytes and bone marrow mesenchymal stem cells (BMSCs) are frequently used as seed cells in cartilage tissue engineering. In the present study, we determined if the co-culture of rabbit articular chondrocytes and BMSCs in vitro promotes the expression of cartilaginous extracellular matrix and, if so, what is the optimal ratio of the two cell types. Cultures of rabbit articular chondrocytes and BMSCs were expanded in vitro and then cultured individually or at a chondrocyte:BMSC ratio of 4:1, 2:1, 1:1, 1:2, 1:4 for 21 days and cultured in DMEM/F12. BMSCs were cultured in chondrogenic induction medium. Quantitative real-time RT-PCR and Western blot were used to evaluate gene expression. In the co-cultures, type II collagen and aggrecan expression increased on days 14 and 21. At the mRNA level, the expression of type II collagen and aggrecan on day 21 was much higher in the 4:1, 2:1, and 1:1 groups than in either the articular chondrocyte group or the induced BMSC group, and the best ratio of co-culture groups seems to be 2:1. Also on day 21, the expression of type II collagen and aggrecan proteins in the 2:1 group was much higher than in all other groups. The results demonstrate that the co-culture of rabbit chondrocytes and rabbit BMSCs at defined ratios can promote the expression of cartilaginous extracellular matrix. The optimal cell ratio appears to be 2:1 (chondrocytes:BMSCs). This approach has potential applications in cartilage tissue engineering since it provides a protocol for maintaining and promoting seed-cell differentiation and function. PMID: 21487642 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Dynamics of Salivary Gland Morphogenesis. J Dent Res. 2011 Apr 12; Authors: Harunaga J, Hsu JC, Yamada KM Salivary glands form during embryonic development by a complex process that creates compact, highly organized secretory organs with functions essential for oral health. The architecture of these glands is generated by branching morphogenesis, revealed by recent research to involve unexpectedly dynamic cell motility and novel regulatory pathways. Numerous growth factors, extracellular matrix molecules, gene regulatory pathways, and mechanical forces contribute to salivary gland morphogenesis, but local gene regulation and morphological changes appear to play particularly notable roles. Here we review these recent advances and their potential application to salivary gland tissue engineering. PMID: 21487116 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Chemically Modified Gelatin as Biomaterial in the Design of New Nanomedicines. Med Chem. 2011 Apr 11; Authors: Lopez-Cebral R, Martín-Pastor M, Parraga JE, Zorzi GK, Seijo B, Sanchez A The synthesis of new polymers has led to dramatic enhancements in the medical field. In particular, new chemical entities provided new prospects in tissue engineering, cellular therapy and drug delivery. However, significant efforts still need to be taken in consideration in order to achieve diverse clinical applications in these fields, which is challenging because of the lack of suitable materials with desired microstructure, permeability, degradation rates, products, and suitable mechanical properties. For these reasons some chemical strategies are focused in back to the nature approaches or, in other words, in improving the properties of natural polymers by chemical modifications. We report that by using a simple chemical modification technique we can obtain new biomaterials, specifically suitable for biomedical applications. Concretely, we describe the chemical modification of gelatin and the suitable characteristics of the modified protein to develop new nanomedicines. This protein was selected because of its enormous potential in biomedicine, which is currently limited due to the difficulty of its use without toxic chemical crosslinkers. The modification of the protein was based on the transformation of the carboxylic group into amido groups after their reaction with polyamines, leading to a positively charged biopolymer. To cationize the gelatin two polyamines where used: ethylenediamine and spermine, the latter being one of the endogenous polyamines which has a very positive influence over cells. This modification was monitored by physico-chemical techniques such as NMR, spectrophotometry and potentiometry. With the most promising modified gelatins we were able to develop nanoparticles using the ionotropic gelation technique. In order to determine the ability of these new nanosystems to associate bioactive molecules we selected a model plasmid DNA. The developed nanosystems were characterized corroborating their ability to associate the genetic material. In conclusion, we were able to obtain a semi-synthetic biomaterial with tunable physico-chemical properties, which can be used to develop new nanosystems with the ability to associate genetic material. We therefore propose that the gelatin, with its chemical modification, provide a unique biomaterial for the development of new nanomedicines. PMID: 21486207 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Commentary on: Clinical applications of mesenchymal stem cells in soft tissue augmentation. Aesthet Surg J. 2010 Nov-Dec;30(6):843-4 Authors: Scheflan M PMID: 21131459 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Staged Stem Cell-enriched Tissue (SET) Injections for Soft Tissue Augmentation in Hostile Recipient Areas: A Preliminary Report. Aesthetic Plast Surg. 2011 Apr 13; Authors: Tiryaki T, Findikli N, Tiryaki D BACKGROUND: Autologous fat transplantation is frequently used for a variety of cosmetic treatments and difficult reconstructive indications such as involutional disorders, hemifacial atrophy, sequelae of radiation therapy, or similar problems. However, the limitations of fat transplantation are well known in such difficult cases, particularly the long-term unpredictability of volume maintenance. The ideal method of preparing autologous fat grafts optimizes tissue survival and reduces the variability of outcomes. We propose that enriching traditionally prepared fat grafts with adipose-derived regenerative cells (ADRCs) represents one such method. METHODS: Using a staged approach, we performed cell-enriched fat transfer by injecting autologous ADRCs into soft tissue that was recently grafted using traditional methods of fat transfer. Over a 3-year period, data were prospectively collected from 29 patients who underwent a single session of stem cell-enriched tissue injections (SET). RESULTS: Cell-enriched grafts ranged in volume from 10 to 390 cc per recipient area and were obtained by manual or automated processes. The mean follow-up period was 10 months. Postoperative atrophy of the injected tissue was minimal and subjectively did not change after 8 weeks. Of note, historically reported rates of atrophy range from 20 to 80%. All patients were satisfied with the primary result with no need for a secondary session except for the cosmetic cases. CONCLUSION: These preliminary results suggest that SET is safe and may provide superior results compared to traditional fat grafting. By performing the procedure in a staged approach, operating room expenses are minimized, which ultimately decreases the cost of the procedure. Adipose-derived regenerative cells may mitigate early ischemia by increasing angiogenesis, decreasing apoptosis, and modulating the local inflammatory response. This technique may be of particular value to the surgeon when grafting high volumes of fat or when faced with hostile recipient area conditions, including fibrosis and post radiation. PMID: 21487913 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Clinical applications of mesenchymal stem cells in soft tissue augmentation. Aesthet Surg J. 2010 Nov-Dec;30(6):838-42 Authors: Hanson SE, Gutowski KA, Hematti P Based on a variety of preclinical studies showing that mesenchymal stem cells (MSC) play a significant role in tissue repair and homeostasis, MSC have rapidly moved into a phase of clinical trials investigating their efficacy as a cell-based therapeutic modality for a diverse group of applications. An emerging body of evidence shows that in addition to being a progenitor cell population with self-renewing and multipotent differentiation capabilities, MSC have unique immunomodulatory properties, making them even more attractive for regenerative medicine. Emerging discoveries in stem cell biology have revealed a multitude of mechanisms through which MSC could potentially augment the current techniques in aesthetic surgery. In this article, the authors review the clinical advances in cell-based therapies relevant to aesthetic surgery, including tissue augmentation, rejuvenation, and regeneration. PMID: 21131458 [PubMed - indexed for MEDLINE] | | | | | | | | | |  | |  | |  |
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