Demonstration of the cellular viability and safety of Enterococcus faecium CRL 183 in experiments of long term

Meniscal injury is more likely to cause a permanent alteration of the biomechanical and biological environment of the knee joint, mainly due to the morphological mismatch and substantial loss of meniscal tissues. Herein, to overcome this challenge, we developed an improved bioink with enhanced printability, while maintaining the biocompatibility of major cellular component of the meniscus, namely fibrochondrocytes. Firstly, cellulose nanofiber (CNF) was mixed with gelatin-alginate thermal-responsive bioinks to improve the printability. Afterward, individual-specific meniscal prototypes based on the 3D reconstruction of MRI data were bioprinted using our bioink. The rheological and printability properties of the bioinks were characterized to select proper bioink content and bioprinting parameters. And then, a series of biological characterizations of the bioprinted samples, such as cell viability, metabolic activity, and extracellular matrix accumulation, were carried out in vitro. The results indicated that superior rheological performance and printability of CNF-modified bioink were achieved, ensuring high-precision bioprinting of specific-designed meniscal prototype when compared with the non-CNF-containing counterparts. Meanwhile, biological tests indicated that fibrochondrocytes encapsulated within the CNF-modified bioink maintained long-term cellular viability as well as acceptable extracellular matrix accumulation. This study demonstrates that the CNF-modified bioink is in favor of the printing fidelity of specific meniscus by improved rheological properties, minimizing the mismatch between artificial meniscal implants and native knee joint tissues, thereby permitting the evolution of clinical therapeutic methods of meniscal reconstruction.

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Role of Cells in Freezing-Induced Cell-Fluid Matrix Interactions Within Engineered Tissues

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80531 ◽

2012 ◽

Cited By ~ 1

Author(s):

Angela Seawright ◽

Altug Ozcelikkale ◽

J. Craig Dutton ◽

Bumsoo Han

Keyword(s):

Tissue Engineering ◽

Extracellular Matrix ◽

Regenerative Medicine ◽

Biological Tissues ◽

Cellular Viability ◽

Long Term Storage ◽

Matrix Interactions ◽

Term Storage

Cryopreservation can provide long-term storage of various biological tissues, which has significant impact on tissue engineering and regenerative medicine. For successful cryopreservation of tissues, tissue functionality must be maintained including physical properties such as mechanical, optical, and transport properties, as well as cellular viability. Such properties are associated with the extracellular matrix (ECM) microstructure. Thus, the preservation of the ECM microstructure may lead to successful cryopreservation [1,2]. Yet, there is still very little known about changes in the ECM microstructure during freezing/thawing.

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Erratum to “Effect of cryopreservation and microencapsulation of lactic acid bacterium Enterococcus faecium MC13 for long term storage” [Biochem. Eng. J. 58–59 (2011) 140–147]

Biochemical Engineering Journal ◽

10.1016/j.bej.2012.02.001 ◽

2012 ◽

Vol 63 ◽

pp. 135-136

Author(s):

Paulraj Kanmani ◽

R. Satish Kumar ◽

N. Yuvaraj ◽

K.A. Paari ◽

V. Pattukumar ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacterium ◽

Enterococcus Faecium ◽

Long Term Storage ◽

Term Storage

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Persistence of Animal and Human Glycopeptide-Resistant Enterococci on Two Norwegian Poultry Farms Formerly Exposed to Avoparcin Is Associated with a Widespread Plasmid-Mediated vanA Element within a Polyclonal Enterococcus faecium Population

Applied and Environmental Microbiology ◽

10.1128/aem.71.1.159-168.2005 ◽

2005 ◽

Vol 71 (1) ◽

pp. 159-168 ◽

Cited By ~ 53

Author(s):

P. J. Johnsen ◽

J. I. Ã¯Â¿Â½sterhus ◽

H. Sletvold ◽

M. SÃ¯Â¿Â½rum ◽

H. Kruse ◽

...

Keyword(s):

Enterococcus Faecium ◽

Pcr Amplification ◽

Housekeeping Gene ◽

Inverse Pcr ◽

Glycopeptide Resistance ◽

Physical Linkage ◽

Poultry Farms ◽

The Right ◽

Changes Over Time

ABSTRACT The evolutionary processes responsible for the long-term persistence of glycopeptide-resistant Enterococcus faecium (GREF) in nonselective environments were addressed by genetic analyses of E. faecium populations in animals and humans on two Norwegian poultry farms that were previously exposed to avoparcin. A total of 222 fecal GREF (n = 136) and glycopeptide-susceptible (n = 86) E. faecium (GSEF) isolates were obtained from farmers and poultry on three separate occasions in 1998 and 1999. Pulsed-field gel electrophoresis (PFGE) and plasmid DNA analyses discerned 22 GREF and 32 GSEF PFGE types within shifting polyclonal animal and human E. faecium populations and indicated the presence of transferable plasmid-mediated vanA resistance, respectively. Examples of dominant, persistent GREF PFGE types supported the notion that environmentally well-adapted GREF types may counteract the reversal of resistance. PFGE analyses, sequencing of the purK housekeeping gene, and partial typing of vanA-containing Tn1546 suggested a common animal and human reservoir of glycopeptide resistance. Inverse PCR amplification and sequence analyses targeting the right end of the Tn1546-plasmid junction fragment strongly indicated the presence of a common single Tn1546-plasmid-mediated element in 20 of 22 GREF PFGE types. This observation was further strengthened by vanY-vanZ hybridization analyses of plasmid DNAs as well as the finding of a physical linkage between Tn1546 and a putative postsegregation killing system for seven GREF PFGE types. In conclusion, our observations suggest that the molecular unit of persistence of glycopeptide resistance is a common mobile plasmid-mediated vanA-containing element within a polyclonal GREF population that changes over time. In addition, we propose that “plasmid addiction systems” may contribute to the persistence of GREF in nonselective environments.

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Control of Transmission of Vancomycin-Resistant Enterococcus faecium in a Long-Term–Care Facility

Infection Control and Hospital Epidemiology ◽

10.1086/501623 ◽

1999 ◽

Vol 20 (05) ◽

pp. 312-317 ◽

Cited By ~ 51

Author(s):

Maxine Armstrong-Evans ◽

Margaret Litt ◽

Margaret A. McArthur ◽

Barbara Willey ◽

Darlene Cann ◽

...

Keyword(s):

Enterococcus Faecium ◽

Long Term Care ◽

Care Facility ◽

Control Measures ◽

Term Care ◽

Long Term Care Facility ◽

Rectal Swabs ◽

Vancomycin Resistant ◽

And Control

AbstractObjectives:To describe the investigation and control of transmission of vancomycin-resistant enterococci (VRE) in a residential long-term-care (LTC) setting.Outbreak Investigation:A strain of vancomycin-resistantEnterococcus faeciumnot previously isolated in Ontario colonized five residents of a 254-bed LTC facility in Toronto. The index case was identified when VRE was isolated from a urine culture taken after admission to a local hospital. Screening of rectal swabs from all 235 residents identified four others who were colonized with the same strain ofE faecium.Control Measures:Colonized residents were cohorted. VRE precautions were established as follows: gown and gloves for resident contact, restriction of contact between colonized and noncolonized residents, no sharing of personal equipment, and daily double-cleaning of residents' rooms and wheelchairs.Outcome:Two colonized residents died of causes unrelated to VRE. Although bacitracin therapy (75,000 units four times a day X 14 days) failed to eradicate carriage in two of three surviving residents, both cleared their carriage within 7 weeks. Repeat rectal swabs from 224 residents (91%) 2 months after isolation precautions were discontinued and from 125 residents (51%) 9 months later identified no new cases. Total cost of investigation and control was $12,061 (Canadian).Conclusion:VRE may be transmitted in LTC facilities, and colonized LTC residents could become important VRE reservoirs. Control of VRE transmission in LTC facilities can be achieved even with limited resources.

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INVESTIGATION OF VARIOUS WAYS TO STABILIZE LACTIC ACID BACTERIA CELLS DURING LONG-TERM STORAGE

BIOTECHNOLOGY: STATE OF THE ART AND PERSPECTIVES ◽

10.37747/2312-640x-2020-18-388-389 ◽

2020 ◽

pp. 388-389

Author(s):

Yu. Nikolaev ◽

R. Ulanova ◽

I. Shakir ◽

A. Khreptugova

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Lactic Acid Bacterium ◽

Enterococcus Faecium ◽

Term Survival ◽

Long Term Survival ◽

Long Term Storage ◽

Term Storage

Various methods of stabilizing the cells of the lactic acid bacterium Enterococcus faecium during long-term storage were studied. It is shown that the long-term survival of E. faecium is promoted by the addition of Enterosgel, Polysorb, the use of LB substratum, as well as their immobilization in humic-silanol gel.

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Crosstalk between Substrates and Rho-Associated Kinase Inhibitors in Cryopreservation of Tissue-Engineered Constructs

Stem Cells International ◽

10.1155/2017/1380304 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Arindam Bit ◽

Awanish Kumar ◽

Abhishek Kumar Singh ◽

Albert A. Rizvanov ◽

Andrey P. Kiassov ◽

...

Keyword(s):

Tissue Engineering ◽

Stem Cells ◽

Regenerative Medicine ◽

Kinase Inhibitors ◽

Cell Attachment ◽

Human Mesenchymal Stem Cells ◽

Cellular Viability ◽

Technical Limitation ◽

Engineered Tissues

It is documented that human mesenchymal stem cells (hMSCs) can be differentiated into various types of cells to present a tool for tissue engineering and regenerative medicine. Thus, the preservation of stem cells is a crucial factor for their effective long-term storage that further facilitates their continuous supply and transportation for application in regenerative medicine. Cryopreservation is the most important, practicable, and the only established mechanism for long-term preservation of cells, tissues, and organs, and engineered tissues; thus, it is the key step for the improvement of tissue engineering. A significant portion of MSCs loses cellular viability while freeze-thawing, which represents an important technical limitation to achieving sufficient viable cell numbers for maximum efficacy. Several natural and synthetic materials are extensively used as substrates for tissue engineering constructs and cryopreservation because they promote cell attachment and proliferation. Rho-associated kinase (ROCK) inhibitors can improve the physiological function and postthaw viability of cryopreserved MSCs. This review proposes a crosstalk between substrate topology and interaction of cells with ROCK inhibitors. It is shown that incorporation of ionic nanoparticles in the presence of an external electrical field improves the generation of ROCK inhibitors to safeguard cellular viability for the enhanced cryopreservation of engineered tissues.

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Clinical Impact of Cryopreservation on Split Thickness Skin Grafts in the Porcine Model

Journal of Burn Care & Research ◽

10.1093/jbcr/irz145 ◽

2019 ◽

Vol 41 (2) ◽

pp. 306-316 ◽

Cited By ~ 2

Author(s):

Paul W Holzer ◽

Alexandre G Lellouch ◽

Krysta Moulton ◽

Laurence Zhu ◽

Zhi Yang Ng ◽

...

Keyword(s):

Genetically Engineered ◽

Cellular Viability ◽

Skin Grafts ◽

Porcine Skin ◽

Clinical Value ◽

Promising Alternative ◽

Severe Burns ◽

Duration Of Storage

Abstract Vital, genetically engineered, porcine xenografts represent a promising alternative to human cadaveric allografts (HCA) in the treatment of severe burns. However, their clinical value would be significantly enhanced if preservation and long-term storage—without the loss of cellular viability—were feasible. The objective of this study was to examine the direct impact of cryopreservation and the length of storage on critical in vivo and in vitro parameters, necessary for a successful, potentially equivalent substitute to HCA. In this study, vital, porcine skin grafts, continuously cryopreserved for more than 7 years were compared side-by-side to otherwise identically prepared skin grafts stored for only 15 minutes. Two major histocompatibility complex (MHC)-controlled donor–recipient pairs received surgically created deep-partial wounds and subsequent grafting with split-thickness porcine skin grafts, differentiated only by the duration of storage. Clinical and histological outcomes, as well as quantification of cellular viability via a series of 3-4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide (MTT) assays, were assessed. No statistically significant differences were observed between skin grafts cryopreserved for 15 minutes vs 7 years. Parametric distinctions between xenografts stored for short- vs long-term durations could not be ascertained across independent clinical, histological, or in vitro evaluative methods. The results of this study validate the ability to reliably preserve, store, and retain the essential metabolic activity of porcine tissues after cryopreservation. Plentiful, safe, and readily accessible inventories of vital xenografts represent an advantageous solution to numerous limitations associated with HCA, in the treatment of severe burns.

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