Biohybrid artificial organs encompass all devices capable of substituting for an organ or tissue function and are fabricated from both synthetic materials and living cells. The viability of engineered tissue could be related to the viability of implanted cells. The system of viability assay for mammalian cell culture can be applied to the determination of cell viability for engineered tissue. This review explores various methods of cell viability assay which can be applied to the viability evaluation of engineered tissue. The major criteria employed in viability assays include survival and growth in tissue culture, functional assay, metabolite incorporation, structural altercation, and membrane integrity. Each viability assay method is based on different definitions of cell viability, and has inherent advantages and disadvantages. In order to be able to assess the viability of cells with one assay method, it is desirable to compare the viability measurements from various assays derived from different criteria.
Animal ; Biomedical Engineering*/methods ; Cell Division ; Cell Survival ; Human

Berardinelli lipodystrophy syndrome is a rare autosomal recessive disorder, characterized by loss of body fat, muscular hypertrophy, acanthosis nigricans, hepatomegaly, hyperlipidemia, insulin resistant diabetes, and elevated metabolic rate. The mechanism(s) responsible for these abnormalities is not known. We report a forteen-month old girl with Berardinelli Lipodystriphy Syndrome, who had signs above mentioned, with a brief review and its related literatures.
Acanthosis Nigricans ; Adipose Tissue ; Female ; Hepatomegaly ; Humans ; Hyperlipidemias ; Hypertrophy ; Insulin ; Lipodystrophy*

Polytetrafluoroethylene (PTFE), polyurethane (PU) and silicone are widely known biocompatible polymers which are commonly used for vascular grafts. However, in vitro and in vivo calcifications of these polymers have been found to seriously compromise their quality as biomaterials. In consideration of this problem, the present study compared the calcification rate and extent of PTFE, PU and silicone. Using the in vitro flow-type method, PTFE, PU and silicone films were tested for 1, 4, 7, 10, 14 and 21 days. After 21 days of in vitro calcification test, the calcium levels on PTFE, PU and silicone were 35.89 5.01 microgram /cm2, 23.73 0.68 microgram/cm2 and 19.86 5.28 microgram/cm2, respectively. The higher observed calcium level for PTFE may be due to the effect of the rough surface of PTFE in accumulating calcium ions on the polymer surface. From the 7th day of test, the [Ca]/[P] molar ratio started to decrease over time, and PTFE showed a faster calcification process. This decreasing [Ca]/[P] molar ratio demonstrated the typical calcification mechanism consisting of phosphorus ion accumulation following calcium ion accumulation. This study concluded that PU and silicone are less calcified than PTFE film, a finding in good agreement with previously published studies.
Biocompatible Materials/*adverse effects ; *Blood Vessel Prosthesis ; Calcinosis/*etiology ; Comparative Study ; Microscopy, Electron, Scanning ; Polytetrafluoroethylene/*adverse effects ; Polyurethanes/*adverse effects ; Silicones/*adverse effects

Collagen-based membranous materials of various shapes (gel, film, sponge) are known to be the most promising materials in terms of facilitating the regeneration of dermal defects. In this study, dense and porous collagen membranes were fabricated using air-drying and freeze-drying processes, respectively, and the effect of ultraviolet (UV) radiation on the degree of membrane crosslinking was evaluated by in vitro biodegradation and mechanical testing. A non-irradiated membrane group was used as the negative control and a glutaraldehyde (GA) treated group as the positive control. Scanning electron microscopy showed that, as the freezing temperature decreased to -196 degrees C, the resultant mean pore sizes also decreased; optimal pore size was obtained at a freezing temperature of -70 degrees C. In vitro biodegradation and mechanical testing demonstrated that GA treatment or 4 hours of exposure to UV radiation significantly increased both resistance to collagenase and mechanical strength versus the untreated controls, regardless of the collagen membrane type (dense or porous). Our results suggest that UV treatment is a useful tool for the fabrication of collagen membranes designed to be used as dermal dressings.
Animal ; Cattle ; Collagen/ultrastructure ; Collagen/radiation effects* ; Collagen/metabolism ; Elasticity ; Membranes, Artificial* ; Microscopy, Electron, Scanning ; Porosity ; Tensile Strength ; Ultraviolet Rays*

PURPOSE:In idiopathic central precocious puberty(CPP), characterized by premature but otherwise normal puberty, the early onset of the pubertal growth spurt with increased height velocity results in premature epiphyseal closure with reduced final height. We examined the growth and growth-determining factors in female patients with CPP treated with a long-acting luteinizing hormone-releasing hormone analogue(Tryptorelin). METHODS:Ten female patients who were diagnosed as idiopathic precocious puberty were treated with Tryptorelin(0.06mg/kg, IM every 4 weeks) for 2 years. We evaluated the patients into two groups(Group A, 4 cases, predicted adult height before treatment were less than 150cm; Group B, 6 cases, predicted adult height before treatment were 150cm or greater), and analysed the growth and its determing factors. RESULTS:In total patients, the growth velocity during the second year were decreased to 4.1+/-1.9 from 5.7+/-2.2/yr during the first year(p>0.05) and no significant difference was found in predicted adult height(PAH) before and after 2 years of treatment(152.3+/-6.7 vs. 1453.9+/-6.8cm). The difference between the PAH before and after 2 years of treatment was not correlated with age, bone age, PAH, height standard deviation score(Ht SDS) before treatment, but correlated with difference between the PAH before and after 1 year of treatment(r=0.89310, P=0.0005). The mean Ht SDS for bone age in group A were significantly lower than those in group B(P<0.05). In group A, the mean PAH increased from 147.0+/-1.9 to 153.7+/-3.7cm during two years of treatment, but no difference in PAH was found in group B. So PAH were similar in two groups(154.1+/-8.7 vs. 153.7+/-3.7cm) after second year. The mean difference between bone age and chronological age decreased from 4.5+/-1.3 to 3.0+/-1.3 years in group A(P<0.05). CONCLUSION: Long-term Tryptorelin treatment is more effective in girls with idiopathic central precocious puberty, whose PAH before treatment were below 150cm. If PAH before treatment is 150 cm or greater or increase in PAH during the first year of treatment is poor, this treatment modality might be useless in terms of improved growth.
Adolescent ; Adult ; Female* ; Gonadotropin-Releasing Hormone* ; Humans ; Lutein* ; Puberty ; Puberty, Precocious*

OBJECTIVE: Neural tissue transplantation has been a promising strategy for the treatment of Parkinson's disease (PD). However, transplantation has the disadvantages of low-cell survival and/or development of dyskinesia. Transplantation of cell aggregates has the potential to overcome these problems, because the cells can extend their axons into the host brain and establish synaptic connections with host neurons. In this present study, aggregates of human brain-derived neural stem cells (HB-NSC) were transplanted into a PD animal model and compared to previous report on transplantation of single-cell suspensions. METHODS: Rats received an injection of 6-OHDA into the right medial forebrain bundle to generate the PD model and followed by injections of PBS only, or HB-NSC aggregates in PBS into the ipsilateral striatum. Behavioral tests, multitracer (2-deoxy-2-[18F]-fluoro-D-glucose ([18F]-FDG) and [18F]-N-(3-fluoropropyl)-2-carbomethoxy-3-(4-iodophenyl)nortropane ([18F]-FP-CIT) microPET scans, as well as immunohistochemical (IHC) and immunofluorescent (IF) staining were conducted to evaluate the results. RESULTS: The stepping test showed significant improvement of contralateral forelimb control in the HB-NSC group from 6-10 weeks compared to the control group (p<0.05). [18F]-FP-CIT microPET at 10 weeks posttransplantation demonstrated a significant increase in uptake in the HB-NSC group compared to pretransplantation (p<0.05). In IHC and IF staining, tyrosine hydroxylase and human beta2 microglobulin (a human cell marker) positive cells were visualized at the transplant site. CONCLUSION: These results suggest that the HB-NSC aggregates can survive in the striatum and exert therapeutic effects in a PD model by secreting dopamine.
Animals ; Axons ; Brain ; Cell Transplantation ; Dopamine ; Dyskinesias ; Forelimb ; Humans ; Medial Forebrain Bundle ; Models, Animal* ; Neural Stem Cells* ; Neurons ; Oxidopamine ; Parkinson Disease* ; Rats ; Suspensions ; Tissue Transplantation ; Transplants ; Tyrosine 3-Monooxygenase

No abstract available.
Survival Rate* ; Wilms Tumor*

No abstract available.
Survival Rate* ; Wilms Tumor*

Osteoclasts, together with osteoblasts, control the amount of bone tissue and regulate bone remodeling. Osteoclast differentiation is an important factor related to the pathogenesis of bone-loss related diseases. Reactive oxygen species (ROS) acts as a signal mediator in osteoclast differentiation. Simvastatin, which inhibits 3-hydroxy-3-methylglutaryl coenzyme A, is a hypolipidemic drug which is known to affect bone metabolism and suppresses osteoclastogenesis induced by receptor activator of nuclear factor-kappaB ligand (RANKL). In this study, we analyzed whether simvastatin can inhibit RANKL-induced osteoclastogenesis through suppression of the subsequently formed ROS and investigated whether simvastatin can inhibit H2O2-induced signaling pathways in osteoclast differentiation. We found that simvastatin decreased expression of tartrate-resistant acid phosphatase (TRAP), a genetic marker of osteoclast differentiation, and inhibited intracellular ROS generation in RAW 264.7 cell lines. ROS generation activated NF-kappaB, protein kinases B (AKT), mitogen-activated protein kinases signaling pathways such as c-JUN N-terminal kinases, p38 MAP kinases as well as extracellular signal-regulated kinase. Simvastatin was found to suppress these H2O2-induced signaling pathways in osteoclastogenesis. Together, these results indicate that simvastatin acts as an osteoclastogenesis inhibitor through suppression of ROS-mediated signaling pathways. This indicates that simvastatin has potential usefulness for osteoporosis and pathological bone resorption.
Acid Phosphatase/genetics/metabolism ; Animals ; Anticholesteremic Agents/*pharmacology ; Blotting, Western ; *Cell Differentiation ; Cells, Cultured ; Hydrogen Peroxide/pharmacology ; Isoenzymes/genetics/metabolism ; Macrophages/cytology/drug effects/metabolism ; Mice ; Mitogen-Activated Protein Kinases/genetics/metabolism ; NF-kappa B/genetics/metabolism ; Osteoclasts/*cytology/*drug effects/metabolism ; RANK Ligand/metabolism ; RNA, Messenger/genetics ; Reactive Oxygen Species/*metabolism ; Real-Time Polymerase Chain Reaction ; Simvastatin/*pharmacology

BACKGROUND: As stem cells are considered a promising cell source for tissue engineering, many culture strategies have been extensively studied to generate in vitro stem cell-based tissue constructs. However, most approaches using conventional tissue culture plates are limited by the lack of biological relevance in stem cell microenvironments required for neotissue formation. In this study, a novel perfusion rotating wall vessel (RWV) bioreactor was developed for massproduction of stem cell-based 3D tissue constructs. METHODS: An automated RWV bioreactor was fabricated, which is capable of controlling continuous medium perfusion, highly efficient gas exchange with surrounding air, as well as low-intensity pulsed ultrasound (LIPUS) stimulation. Embryonic stem cells encapsulated in alginate/gelatin hydrogel were cultured in the osteogenic medium by using our bioreactor system. Cellular viability, growth kinetics, and osteogenesis/mineralization were thoroughly evaluated, and culture media were profiled at real time. The in vivo efficacy was examined by a rabbit cranial defect model. RESULTS: Our bioreactor successfully maintained the optimal culture environments for stem cell proliferation, osteogenic differentiation, and mineralized tissue formation during the culture period. The mineralized tissue constructs produced by our bioreactor demonstrated higher void filling efficacy in the large bone defects compared to the group implanted with hydrogel beads only. In addition, the LIPUS modules mounted on our bioreactor successfully reached higher mineralization of the tissue constructs compared to the groups without LIPUS stimulation. CONCLUSION This study suggests an effective biomanufacturing strategy for mass-production of implantable mineralized tissue constructs from stem cells that could be applicable to future clinical practice.