scholarly journals A 3D Bioprinted Human Meniscus Shape Enriched with Mesenchymal Cells

2021 ◽  
Vol 11 (24) ◽  
pp. 11733
Author(s):  
Mihai Hurmuz ◽  
Mihai Ionac ◽  
Carmen Tatu ◽  
Daniela Puscasiu ◽  
Catalin Adrian Miu ◽  
...  
Keyword(s):  
Cell Viability ◽  
Viable Cell ◽  
Mesenchymal Cells ◽  
Maximum Force ◽  
Infrapatellar Fat Pad ◽  
Buffer Solution ◽  
Human Organ ◽  
Printing Process ◽  
Nanofibrillar Cellulose ◽  
The Mean

Background and objectives: Regenerative medicine, with its massive development over the years, has the potential to solve some of the most problematic medical issues, such as functional organ transplantation. The aim of this study was to create a human meniscal shape 3D-printed enriched with human adipose-derived mesenchymal cells. Materials and Methods: Human infrapatellar fat pad was harvested, and mesenchymal cells were isolated. The mesenchymal stem cells were differentiated to the chondrocite lineage and a hydrogel (a nanofibrillar cellulose, sodium alginate, D-mannitol, and Hepes buffer solution combination) cell mixture was bioprinted to create three human-size meniscus structures. The obtained structures were evaluated regarding the cell viability, appropriate size in relation to a native meniscus, and some mechanical characteristics. Results: The human meniscal shape created respected the anatomic characteristic of a native structure. Cell viability of approximately 97% and extracellular matrix formation after the printing process were observed. The mean maximum force for the meniscus with mesenchymal cells was 6.5 N (+/−0.5 N) compared to the mean maximum force for the native meniscus of 10.32 N (+/−0.7 N), which is statistically relevant (p < 0.01). Conclusion: This paper presents the potential of bioprinting viable cell structures that could in the future present enough mechanical strength to replace a human organ, such as a meniscus. There are still limitations regarding the ink and the printing process, but we are confident that these problems will soon be solvable.

scholarly journals Applied Force during Piston Prosthesis Placement in a 3D-Printed Model: Freehand vs Robot-Assisted Techniques

2018 ◽  
Vol 160 (2) ◽  
pp. 320-325 ◽  
Author(s):  
Christopher R. Razavi ◽  
Paul R. Wilkening ◽  
Rui Yin ◽  
Nicolas Lamaison ◽  
Russell H. Taylor ◽  
...  
Keyword(s):  
Middle Ear ◽  
Force Sensor ◽  
Neck Surgery ◽  
Maximum Force ◽  
Maximum Magnitude ◽  
Robot Assisted ◽  
Freehand Technique ◽  
Stapes Prosthesis ◽  
3D Printed ◽  
The Mean

Objectives To describe a 3D-printed middle ear model that quantifies the force applied to the modeled incus. To compare the forces applied during placement and crimping of a stapes prosthesis between the Robotic ENT Microsurgery System ( REMS) and the freehand technique in this model. Study Design Prospective feasibility study. Setting Robotics laboratory. Subjects and Methods A middle ear model was designed and 3D printed to facilitate placement and crimping of a piston prosthesis. The modeled incus was mounted to a 6–degree of freedom force sensor to measure forces/torques applied on the incus. Six participants—1 fellowship-trained neurotologist, 2 neurotology fellows, and 3 otolaryngology–head and neck surgery residents—placed and crimped a piston prosthesis in this model, 3 times freehand and 3 times REMS assisted. Maximum force applied to the incus was then calculated for prosthesis placement and crimping from force/torque sensor readings for each trial. Robotic and freehand outcomes were compared with a linear regression model. Results Mean maximum magnitude of force during prosthesis placement was 126.4 ± 73.6 mN and 105.0 ± 69.4 mN for the freehand and robotic techniques, respectively ( P = .404). For prosthesis crimping, the mean maximum magnitude of force was 469.3 ± 225.2 mN for the freehand technique and 272.7 ± 97.4 mN for the robotic technique ( P = .049). Conclusions Preliminary data demonstrate that REMS-assisted stapes prosthesis placement and crimping are feasible with a significant reduction in maximum force applied to the incus during crimping with the REMS in comparison with freehand.

scholarly journals Directional Selection of Microbial Community Reduces Propionate Accumulation in Glycerol and Glucose Anaerobic Bioconversion Under Elevated pCO2

2021 ◽  
Vol 12 ◽  
Author(s):  
Pamela Ceron-Chafla ◽  
Yu-ting Chang ◽  
Korneel Rabaey ◽  
Jules B. van Lier ◽  
Ralph E. F. Lindeboom
Keyword(s):  
Microbial Community ◽  
Cell Viability ◽  
Cell Density ◽  
Viable Cell ◽  
Viable Cell Density ◽  
Directional Selection ◽  
Adaptive Laboratory Evolution ◽  
Glycerol Conversion ◽  
Microbial Groups ◽  
Selection Of

Volatile fatty acid accumulation is a sign of digester perturbation. Previous work showed the thermodynamic limitations of hydrogen and CO2 in syntrophic propionate oxidation under elevated partial pressure of CO2 (pCO2). Here we study the effect of directional selection under increasing substrate load as a strategy to restructure the microbial community and induce cross-protection mechanisms to improve glucose and glycerol conversion performance under elevated pCO2. After an adaptive laboratory evolution (ALE) process, viable cell density increased and predominant microbial groups were modified: an increase in Methanosaeta and syntrophic propionate oxidizing bacteria (SPOB) associated with the Smithella genus was found with glycerol as the substrate. A modest increase in SPOB along with a shift in the predominance of Methanobacterium toward Methanosaeta was observed with glucose as the substrate. The evolved inoculum showed affected diversity within archaeal spp. under 5 bar initial pCO2; however, higher CH4 yield resulted from enhanced propionate conversion linked to the community shifts and biomass adaptation during the ALE process. Moreover, the evolved inoculum attained increased cell viability with glucose and a marginal decrease with glycerol as the substrate. Results showed differences in terms of carbon flux distribution using the evolved inoculum under elevated pCO2: glucose conversion resulted in a higher cell density and viability, whereas glycerol conversion led to higher propionate production whose enabled conversion reflected in increased CH4 yield. Our results highlight that limited propionate conversion at elevated pCO2 resulted from decreased cell viability and low abundance of syntrophic partners. This limitation can be mitigated by promoting alternative and more resilient SPOB and building up biomass adaptation to environmental conditions via directional selection of microbial community.

scholarly journals Effect of alternative on-site wastewater treatment on the viability and culturability of Salmonella choleraesuis

2005 ◽  
Vol 3 (1) ◽  
pp. 1-14 ◽  
Author(s):  
J. W. Pundsack ◽  
R. E. Hicks ◽  
R. P. Axler
Keyword(s):  
Wastewater Treatment ◽  
Cell Viability ◽  
High Strength ◽  
Viable Cell ◽  
Viable Count ◽  
Treatment System ◽  
Test Facility ◽  
Septic Tank ◽  
Salmonella Choleraesuis ◽  
Wastewater Treatment Systems

The objective of this study was to determine how alternative on-site wastewater treatment systems (i.e. subsurface flow constructed wetlands, intermittent sand filters and intermittent peat filters) affect the viability and culturability of Salmonella choleraesuis (serotype typhimurium, ATCC 23567). Influent was a high strength septic tank effluent (BOD5 240–344 mg L−1, TN ∼100 mg L−1, TP ∼ 15 mg L−1) at the Natural Resources Research Institute's (NRRI) alternative treatment system test facility in northern Minnesota. Treatment systems were inoculated with cultures of S. choleraesuis for 5–7 consecutive days in summer and winter during 1998–99. After the seeding, outflow samples were taken until Salmonella counts were sustained at background levels. In addition to culture-based enumeration, S. choleraesuis abundances were also measured using fluorescent in situ hybridization (FISH) alone and in combination with the direct viable count method (DVC) to determine if plate counts underestimated total and viable Salmonella abundances and if the Salmonella cell viability changed after passing through the treatment systems. In most cases, total and viable cell abundances in treatment system effluents were several orders of magnitude higher than cultured cell abundances. Our results indicate that the culture-based method underestimated viable concentrations of the model pathogen, S. choleraesuis. Salmonella cell viability decreased in effluents during the summer but increased during the winter. Using a culture-based enumeration method alone to determine removal efficiencies of bacterial indicators and pathogens for wastewater treatment systems may result in artificially high estimates of effective treatment.

scholarly journals Butyrate Permeation across the Isolated Ovine Reticulum Epithelium

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2198
Author(s):  
Reiko Rackwitz ◽  
Franziska Dengler ◽  
Gotthold Gäbel
Keyword(s):  
Fatty Acids ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Short Chain Fatty Acids ◽  
Monocarboxylate Transporters ◽  
Buffer Solution ◽  
Mean Values ◽  
Ussing Chambers ◽  
Rumen Epithelium ◽  
The Mean

We hypothesized that, due to the high pH of this compartment, the reticulum epithelium displays particular features in the transport of short-chain fatty acids (SCFA). Ovine reticulum epithelium was incubated in Ussing chambers using a bicarbonate-free buffer solution containing butyrate (20 mmol L−1). p-hydroxymercuribenzoic acid (pHMB), 5-(N-Ethyl-N-isopropyl)amiloride (EIPA), or ouabain were added to the buffer solution as inhibitors of monocarboxylate transporters, sodium-proton-exchangers, or the Na+/K+-ATPase, respectively. The short-circuit current (Isc) and transepithelial conductance (Gt) were monitored continuously while the flux rates of 14C-labelled butyrate were measured in the mucosal-to-serosal (Jmsbut) or serosal-to-mucosal direction (Jsmbut). Under control conditions, the mean values of Isc and Gt amounted to 2.54 ± 0.46 µEq cm−2 h−1 and 6.02 ± 3.3 mS cm−2, respectively. Jmsbut was 2.1 ± 1.01 µmol cm−2 h−1 on average and about twice as high as Jsmbut. Incubation with ouabain reduced Jmsbut, while Jsmbut was not affected. The serosal addition of EIPA did not affect Jmsbut but reduced Jsmbut by about 10%. The addition of pHMB to the mucosal or serosal solution reduced Jmsbut but had no effect on Jsmbut. Mucosally applied pHMB provoked a transient increase in the Isc. The serosal pHMB sharply reduced Isc. Our results demonstrate that butyrate can be effectively transported across the reticulum epithelium. The mechanisms involved in this absorption differ from those known from the rumen epithelium.

scholarly journals Human Infrapatellar Fat Pad-Derived Stromal Cells have more Potent Differentiation Capacity than other Mesenchymal Cells and can be Enhanced by Hyaluronan

2015 ◽  
Vol 24 (7) ◽  
pp. 1221-1232 ◽  
Author(s):  
Dah-Ching Ding ◽  
Kun-Chi Wu ◽  
Hsiang-Lan Chou ◽  
Wei-Ting Hung ◽  
Hwan-Wun Liu ◽  
...  
Keyword(s):  
Stromal Cells ◽  
Mesenchymal Cells ◽  
Infrapatellar Fat Pad ◽  
Fat Pad ◽  
Differentiation Capacity

Controlled Release Characteristics of PLA-Pluronic-PLA Nano-Sized Vesicles In Vitro

2013 ◽  
Vol 785-786 ◽  
pp. 493-497
Author(s):  
Yu Ping Li ◽  
Li Zhen Sun ◽  
Xiang Yuan Xiong ◽  
Zi Ling Li ◽  
Ting Kang Xing ◽  
...  
Keyword(s):  
Controlled Release ◽  
Protein Delivery ◽  
Phosphate Buffer Solution ◽  
Entrapment Efficiency ◽  
Poly Lactic Acid ◽  
Oral Insulin ◽  
Buffer Solution ◽  
The Mean ◽  
The Stability

In the present study, controlled release characteristics of new nanosized PLA-Pluronic-PLA block copolymer vesicles comprising of amphiphilic poly (lactic acid) (PLA) and Pluronic block copolymers (PEO-PPO-PEO) have been evaluated as an oral insulin carrier. The mean size of vesicles was 78 nm for PLA-F127-PLA and 165 nm for PLA-P85-PLA copolymer. The mean insulin entrapment efficiency was 59.6% for PLA-P85-PLA and 26.4% for PLA-F127-PLA. The in vitro release characteristics of insulin from vesicles exhibited an initial burst in the range of pH 1.2-7.4 dissolution mediums. The presence of PLA-Pluronic-PLA vesicles improved the stability of insulin in the gastrointestinal fluids than that of the phosphate buffer solution (PBS) of insulin. More importantly, the released insulin from the vesicles maintained their biological activity. The results from this studies demonstrated that biodegradable PLA-Pluronic-PLA can self-assemble with insulin, form insulin-encapsulated vesicles, and is good carrier materials for oral insulin/protein delivery.

scholarly journals OBSERVATIONS BY ELECTRON MICROSCOPY ON CONTRACTION OF SKELETAL MYOFIBRILS INDUCED WITH ADENOSINETRIPHOSPHATE

1951 ◽  
Vol 94 (1) ◽  
pp. 9-20 ◽  
Author(s):  
Charles A. Ashley ◽  
Keith R. Porter ◽  
Delbert E. Philpott ◽  
George M. Hass
Keyword(s):  
Structural Changes ◽  
Contractile Response ◽  
Gradual Increase ◽  
Enzymatic Modification ◽  
Buffer Solution ◽  
Solution Ph ◽  
Apparent Increase ◽  
Mean Diameter ◽  
Parallel Arrangement ◽  
The Mean

Skeletal myofibrils isolated either by tryptic digestion at 0° C. or by a colloid mill and suspended in buffer solution (pH 7.0, µ; 0.154) containing 20 per cent glycerin and 0.0025 M adenosinetriphosphate at –5° C. contracted slowly and progressively when the temperature was raised above 0° C. Formalin fixation halted this contraction. With the aid of these procedures myofibrils in progressive stages of contraction were then studied with the electron microscope. Electron micrographs showed that uncontracted fibrils isolated by the colloid mill were structurally similar to those described by other workers. Treatment of fibrils with trypsin removed the Z bands and disorganized the I bands. This enzymatic modification of structure did not impair the contractile response. The principal structural changes during contraction consisted of a migration of dense material from the A band into the A-I junction or the Z band, a gradual increase in width of the fibril, a gradual decrease in length of sarcomeres, an apparent increase in the mean diameter of filaments, and a disorientation of these latter from their parallel arrangement.

scholarly journals Cell viability and electrical response of breast cancer cell treated in aqueous graphene oxide solution deposition on interdigitated electrode

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Muhammad M. Ramli ◽  
A. S. Rosman ◽  
N. S. Mazlan ◽  
M. F. Ahmad ◽  
D. S. C. Halin ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Graphene Oxide ◽  
Cell Viability ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Electrical Impedance ◽  
Cell Membranes ◽  
Electrical Response ◽  
Viable Cell ◽  
Normal Breast

AbstractBreast cancer is one of the most reported cancers that can lead to death. Despite the advances in diagnosis and treatment procedures, the possibility of cancer recurrences is still high in many cases. With that in consideration, researchers from all over the world are showing interest in the unique features of Graphene oxide (GO), such as its excellent and versatile physicochemical properties, to explore further its potential and benefits towards breast cancer cell treatment. In this study, the cell viability and electrical response of GO, in terms of resistivity and impedance towards the breast cancer cells (MCF7) and normal breast cells (MCF10a), were investigated by varying the pH and concentration of GO. Firstly, the numbers of MCF7 and MCF10a were measured after being treated with GO for 24 and 48 h. Next, the electrical responses of these cells were evaluated by using interdigitated gold electrodes (IDEs) that are connected to an LCR meter. Based on the results obtained, as the pH of GO increased from pH 5 to pH 7, the number of viable MCF7 cells decreased while the number of viable MCF10a slightly increased after the incubation period of 48 h. Similarly, the MCF7 also experienced higher cytotoxicity effects when treated with GO concentrations of more than 25 µg/mL. The findings from the electrical characterization of the cells observed that the number of viable cells has corresponded to the impedance of the cells. The electrical impedance of MCF7 decreased as the number of highly insulating viable cell membranes decreased. But in contrast, the electrical impedance of MCF10a increased as the number of highly insulating viable cell membranes increased. Hence, it can be deduced that the GO with higher pH and concentration influence the MCF7 cancer cell line and MCF10a normal breast cell.

scholarly journals Nanofibrillar cellulose wound dressing supports the growth and characteristics of human mesenchymal stem/stromal cells without cell adhesion coatings

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Jasmi Kiiskinen ◽  
Arto Merivaara ◽  
Tiina Hakkarainen ◽  
Minna Kääriäinen ◽  
Susanna Miettinen ◽  
...  
Keyword(s):  
Wound Healing ◽  
Cell Adhesion ◽  
Cell Viability ◽  
Cell Survival ◽  
Cell Transplantation ◽  
Stromal Cells ◽  
Wound Dressing ◽  
Nanofibrillar Cellulose ◽  
Cell Scaffold ◽  
A Cell

Abstract Background In the field of regenerative medicine, delivery of human adipose-derived mesenchymal stem/stromal cells (hASCs) has shown great promise to promote wound healing. However, a hostile environment of the injured tissue has shown considerably to limit the survival rate of the transplanted cells, and thus, to improve the cell survival and retention towards successful cell transplantation, an optimal cell scaffold is required. The objective of this study was to evaluate the potential use of wood-derived nanofibrillar cellulose (NFC) wound dressing as a cell scaffold material for hASCs in order to develop a cell transplantation method free from animal-derived components for wound treatment. Methods Patient-derived hASCs were cultured on NFC wound dressing without cell adhesion coatings. Cell characteristics, including cell viability, morphology, cytoskeletal structure, proliferation potency, and mesenchymal cell and differentiation marker expression, were analyzed using cell viability assays, electron microscopy, immunocytochemistry, and quantitative or reverse transcriptase PCR. Student’s t test and one-way ANOVA followed by a Tukey honestly significant difference post hoc test were used to determine statistical significance. Results hASCs were able to adhere to NFC dressing and maintained high cell survival without cell adhesion coatings with a cell density-dependent manner for the studied period of 2 weeks. In addition, NFC dressing did not induce any remarkable cytotoxicity towards hASCs or alter the morphology, proliferation potency, filamentous actin structure, the expression of mesenchymal vimentin and extracellular matrix (ECM) proteins collagen I and fibronectin, or the undifferentiated state of hASCs. Conclusions As a result, NFC wound dressing offers a functional cell culture platform for hASCs to be used further for in vivo wound healing studies in the future.

scholarly journals Adipose Tissue-Derived Stem Cells Retain Their Adipocyte Differentiation Potential in Three-Dimensional Hydrogels and Bioreactors

Biomolecules ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1070 ◽  
Author(s):  
Benjamen O'Donnell ◽  
Sara Al-Ghadban ◽  
Clara Ives ◽  
Michael L'Ecuyer ◽  
Tia Monjure ◽  
...  
Keyword(s):  
Stem Cells ◽  
Adipose Tissue ◽  
Knee Joint ◽  
Cell Viability ◽  
Adipogenic Differentiation ◽  
Three Dimensional ◽  
Growth Control ◽  
Infrapatellar Fat Pad ◽  
Dapi Staining ◽  
Differentiation Potential

Osteoarthritis (OA) is a common joint disorder with a significant economic and healthcare impact. The knee joint is composed of cartilage and the adjoining bone, a synovial capsule, the infrapatellar fat pad (IPFP), and other connective tissues such as tendons and ligaments. Adipose tissue has recently been highlighted as a major contributor to OA through strong inflammation mediating effects. In this study, methacrylated gelatin (GelMA) constructs seeded with adipose tissue-derived mesenchymal stem cells (ASCs) and cultured in a 3D printed bioreactor were investigated for use in microphysiological systems to model adipose tissue in the knee joint. Four patient-derived ASC populations were seeded at a density of 20 million cells/mL in GelMA. Live/Dead and boron-dipyrromethene/4′,6-diamidino-2-phenylindole (BODIPY/DAPI) staining of cells within the constructs demonstrated robust cell viability after 28 days in a growth (control) medium, and robust cell viability and lipid accumulation in adipogenic differentiation medium. qPCR gene expression analysis and protein analysis demonstrated an upregulated expression of key adipogenesis-associated genes. Overall, these data indicate that ASCs retain their adipogenic potential when seeded within GelMA hydrogels and cultured within perfusion bioreactors, and thus can be used in a 3D organ-on-a-chip system to study the role of the IPFP in the pathobiology of the knee OA.

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