Liu H.-Y.,Taipei Medical University |
Chiou J.-F.,Taipei Medical University Hospital |
Chiou J.-F.,Taipei Medical University |
Wu A.T.H.,Taipei Medical University Hospital |
And 11 more authors.
Biomaterials | Year: 2012
Adipose-derived stem cells (ADSCs) have been shown to be pluoripotent and explored for their usage in tissue engineering. Previously, we have established a cell-based approach comprised of platelet-enriched plasma and osteo-progenitor cells for treating osteoporosis in an ovariectomized-senescence-accelerated mice (OVX-SAMP8) model. In the present study, we intend to explore the feasibility of using ADSCs as a cell-based therapeutic approach for treating osteoporosis, and to examine the effects of aging on the pluoripotency of ADSCs and the efficiency of bone formation both in vitro and in vivo. Flow cytometry was used to characterize ADSCs isolated from young and aged female SAMP8 mice and showed that the highly positive expression of surface markers such as CD44 and CD105 and negative for CD34 and CD45. Therefore, to compare the aging effects on the growth kinetics and differentiation potential of young and aged ADSCs, we found that there was a significant decline in both the proliferation rate (approximately 13.3%) and osteo-differentiation potential in aged ADSC. Subsequently, young and aged ADSCs were transplanted into the bone marrow of osteoporotic mice (OVX-SAMP8) to evaluate their bone formation ability. ADSC transplants were shown effective in restoring bone mineral density in the right/left knees, femurs and spine, 4 months post-transplantation; mice which received young ADSC transplants showed significantly higher bone regeneration(an average of 24.3% of improved BMD) over those received aged ADSCs. In conclusion, these findings showed that aging impedes osteoporosis-ameliorating potential of ADSC by diminishing osteogenic signal, and that ADSC could be used as a potential cell-based therapy for osteoporosis. © 2012 Elsevier Ltd. Source
Tang D.,University of Southampton |
Tare R.S.,University of Southampton |
Yang L.-Y.,Taipei Medical University |
Yang L.-Y.,China Medical University at Taichung |
And 4 more authors.
Biomaterials | Year: 2016
The rising incidence of bone disorders has resulted in the need for more effective therapies to meet this demand, exacerbated by an increasing ageing population. Bone tissue engineering is seen as a means of developing alternatives to conventional bone grafts for repairing or reconstructing bone defects by combining biomaterials, cells and signalling factors. However, skeletal tissue engineering has not yet achieved full translation into clinical practice as a consequence of several challenges. The use of additive manufacturing techniques for bone biofabrication is seen as a potential solution, with its inherent capability for reproducibility, accuracy and customisation of scaffolds as well as cell and signalling factor delivery. This review highlights the current research in bone biofabrication, the necessary factors for successful bone biofabrication, in addition to the current limitations affecting biofabrication, some of which are a consequence of the limitations of the additive manufacturing technology itself. © 2016 Elsevier Ltd. Source
Hemal A.K.,Wake forest University |
Hemal A.K.,Institute of Regenerative Medicine |
Nayyar R.,All India Institute of Medical Sciences |
Gupta N.P.,All India Institute of Medical Sciences |
Dorairajan L.N.,Wake forest University
Urology | Year: 2010
Objectives: To present our experience and outcomes of robot-assisted laparoscopic surgery (RALS) performed for different ureteral pathologies and to discuss the true utility of robotics in ureteral surgery. Methods: We reviewed a total of 44 procedures performed for diverse ureteral pathologies involving the proximal and distal ureter in 2 institutions from July 2006 to July 2009. Operative time, blood loss, length of stay, complications, and subjective and objective follow-up were evaluated. Results: The 44 cases included 18 distal ureteral procedures including 5 distal ureterectomy with ureteroneocystostomy; 1 ureteroneocystostomy with psoas hitch; 2 ureteroneocystostomy with vesicovaginal fistula repair; 9 megaureter repairs in 8 cases; there were 12 proximal ureteral procedures including 7 ureteroureterostomies and 4 retrocaval ureter repairs; 10 ablative procedures consisting of 5 nephroureterectomies with cuff of bladder and 5 nephroureterectomies and 4 miscellaneous procedures. The mean operative time was 137.9 minutes (range: 70-240). Mean blood loss was 98.2 mL (range: <50-400). There were no urine leaks. Mean drain tube duration was 1.4 days (range: 1-2.5) and mean hospital stay was 2.4 days (range: 1-6). Complications included 1 case of sepsis and 1 antibiotic-induced infection. Average follow-up period was 13.5 months. Operative success as defined by symptom resolution and imaging was 100%. Conclusions: RALS is feasible, safe, and an effective option for ureteral pathologies at any level of the ureter with minimal peri-operative morbidity. However, appropriate port placement, patient positioning, and versatile experience of team is critical in handling such cases for better outcomes. © 2010 Elsevier Inc. All rights reserved. Source
Bioengineers at Wake Forest Institute for Regenerative Medicine have taken a large step, ten years in the making, toward functional 3D bioprinted tissue. The team, led by Anthony Atala, M.D., successfully printed an ear, along with bone and muscle structures using what they call the Integrated Tissue and Organ Printing System (ITOP). When implanted beneath the skin of mice and rats, the living tissue not only retained its shape over several months, but grew and developed a system of blood vessels. Another advance in 3D bioprinting was presented Wednesday at the American Chemical Society’s national meeting in San Diego, where a team led by Paul Gatenholm, Ph.D., from the Wallenberg Wood Science Center in Sweden reported on their work producing cartilage in an in vivo mouse model. After 60 days of implantation in mice, the team’s 3D printed combination of polysaccharides, human chondrocytes (cells that build up cartilage), and human mesenchymal stem cells from bone marrow proved successful at encouraging chondrocyte and cartilage production. The findings may one day lead to implants that help heal injured noses, ears and knees. While 3D printing living organs for transplant patients is the ultimate goal of Atala’s group, it is still a long ways off. Still, Atala’s new technique, detailed Feb. 15 in Nature Biotechnology, overcomes previous hurdles to printing functional tissue that is large enough and strong enough for use in humans. “This novel tissue and organ printer is an important advance in our quest to make replacement tissue for patients,” senior author Atala, said in a statement. “It can fabricate stable, human-scale tissue of any shape. With further development, this technology could potentially be used to print living tissue and organ structures for surgical implantation.” Read more: Cotton Candy Machine Could Lead to the Creation of Artificial Organs Previous studies showed that without a network of blood vessels tissues must be smaller than 200 microns (0.007 inches) for cells to be sustained. In the new study, a human, baby-sized ear (1.5 inches), was implanted under the skin of mice. After two months of implantation, it was thriving and blood vessels and cartilage tissues had formed. The New York Times reported that other scientists have engineered human-size ears in mice before, but noted that those did not form blood vessels and cartilage like the current study, or they were not 3D printed. The scientists zeroed in on the optimal combination for their water-based “ink,” which is a mix of cells and gel. Through the ITOP system, the hydrogel is combined with a biodegradable plastic to help maintain the tissues shape while it’s transplanted, and a network of micro-channels flow through the structures to let oxygen and nutrients flow into the body as the structures develop a system of blood vessels. Atala told CNN that with this concept, if a patient as a defect or an injury, they can perform an X-ray of that area and download the information digitally into the software program that drives the print heads, which will then “tailor-make” a structure that will fit the patient using the patient’s own cells. In addition to the ear, the team showed muscle tissue, implanted in rats, was strong enough to became vascularized and induce nerve formation after two weeks. They also printed jaw bone fragments using human stem cells that were the size of a human. The bioprinted bone was implanted in rats and was vascularized five months after implantation. The study received funding from the Armed Forces Institute of Regenerative Medicine. The team hopes that in the future similar results will happen in humans, but for now ongoing studies will measure the long-term success of this effort.
There, at a company started in 2004 by stem cell pioneer James Thomson, Fujifilm found one of the world's most advanced efforts to churn out in vast, predictable quantities powerful cells that might someday be used to cure disease. Fujifilm says the $307 million acquisition of Cellular Dynamics International Inc. it completed in May is key to its ambitious plans in the field of regenerative medicine, which uses cells and other materials to heal damaged tissues and organs. Leading the effort in Madison is Kazuyoshi "Kaz" Hirao, a friendly Tokyo native-turned-Madisonian who enjoys swimming, taking long walks and attending music and theater performances. "The potential is very huge to change the world," said Hirao, chairman and chief executive officer of Cellular Dynamics, or CDI. Already the leader in the manufacture of human cells, CDI is hoping to benefit from Fujifilm's greater resources and global penetration. When Shigetaka Komori, Fujifilm's chairman and chief executive officer, visited in October, he told CDI employees and Gov. Scott Walker that he viewed the Madison company as a key to Fujifilm's future in regenerative medicine. To make its cells - known as iPS, or induced pluripotent stem cells - CDI starts with a small sample of blood or skin. Its scientists, in essence, rewind the cells to create the equivalent of embryonic stem cells. Then they nudge the cells forward in the developmental process to become any of 12 products, including heart, liver and several types of neural cells. "My expectation is that the iPS cell business will be one of the main pillars for new corporate growth," Komori said. When he won the Nobel Prize in 2012 for his work on iPS cells, Japanese scientist Shinya Yamanaka portrayed the cells as a discovery that would have great impact in the future, said Don Gibbons, a spokesman for the California Institute of Regenerative Medicine. That future has begun to arrive, Gibbons said. Nearly every major drug company is using iPS cells for drug discovery or to test the toxicity of compounds under development, he said. For example, they might use heart cells or liver cells created in the lab to test whether a compound would be harmful to those organs. Advantages to using the cells include making animal studies less necessary and bringing down the average cost of making drugs, Gibbons said. A clinical trial - the first in the world involving iPS cells - began in 2014 when Japanese researchers transplanted retinal tissue made using reprogrammed cells into a woman with age-related macular degeneration. The trial was put on hold in July before a second patient could be transplanted because of concerns about mutations in that patient's iPS cells. CDI in 2014 received a $1.2 million contract from the National Eye Institute to engineer cells for the potential treatment of macular degeneration. Researchers at the institute have said they hope to begin a clinical trial in 2017. Over the past decade, as digital film sales dropped, Fujifilm has diversified into a wide range of products, including antiviral drugs,anti-aging skin care products and natural gas purification filters. Now it is eyeing regenerative medicine as an area where it can gain the lead because the field is so new. "The market is early stage, but the potential is very high," Hirao said. Fujifilm plans to marry a homegrown product that acts as a scaffold on which to grow cells with CDI's iPS cells and engineered tissue from Japan Tissue Engineering Co., another recent acquisition. Combining all of these technologies will make valuable products for drug development - and perhaps even for therapies down the road, Hirao said. Hirao, who earned his MBA at the University of Wisconsin-Madison, left his wife and high school-aged son in Japan when he took the CDI job. He and Tak Okada, CDI's chief technology officer, have climbed bluffs at Devil's Lake State Park and are planning a trip to South America. Hirao has held management roles in Fujifilm's pharmaceutical and other divisions. But it was when his father was diagnosed with esophageal cancer five years ago that he says he took a personal interest in regenerative medicine. His business philosophy, honed during a difficult semiconductor company integration and while he was secretary-general of the Japan Netherlands Society from 2012 to 2015, relies heavily on interpersonal communication and trust. Hirao uses a "surprising" graphic to illustrate that, said Bruce Novich, president of Fujifilm North America's new business development division. The graphic shows that the combination of the Japanese characters for "people" and "trust" means "money." "This is a guiding principle for his business dealings," Novich said. And it was key to Hirao's ability to meld three regional business teams into a global business at Fujifilm's semiconductor division, he said. When Hirao arrived at CDI in August, he immediately sat down with Emile Nuwaysir and Chris Parker, its remaining top two executives, and told them they would be part of a team management structure. Then he held meetings with small groups of no more than 15 employees. CDI has 160 employees and is planning with an eye on the potential trajectory of the business over the next five years, Parker said. That means the more than 30,000 square feet that it currently occupies in University Research Park is getting tight. "With the hiring we're doing, we're going to need to deploy additional space," Parker said. Explore further: Japan's Fujifilm to buy US ultrasound maker