Abstract 2748: Monitoring cellular metabolic activity by non-invasive endogenous fluorescence imaging

Background Alveolar overdistension and repetitive derecruitment-recruitment contribute to ventilator-induced lung injury (VILI). The authors investigated (1) whether inflammatory cell activation due to VILI was assessable by positron emission tomography and (2) whether cell activation due to dynamic overdistension alone was detectable when other manifestations of VILI were not yet evident. Methods The authors assessed cellular metabolic activity with [(18)F]fluorodeoxyglucose and regional gas exchange with [(13)N]nitrogen. In 12 sheep, the left ("test") lung was overdistended with end-inspiratory pressure of 50 cm H(2)O for 90 min, while end-expiratory derecruitment of this lung was either promoted with end-expiratory pressure of -10 cm H(2)O in 6 of these sheep (negative end-expiratory pressure [NEEP] group) or prevented with +10 cm H(2)O in the other 6 (positive end-expiratory pressure [PEEP] group) to isolate the effect of overdistension. The right ("control") lung was protected from VILI. Results Aeration decreased and shunt fraction increased in the test lung of the NEEP group. [(18)F]fluorodeoxyglucose uptake of this lung was higher than that of the control lung and of the test lung of the PEEP group, and correlated with neutrophil count. When normalized by tissue fraction to account for increased aeration of the test lung in the PEEP group, [(18)F]fluorodeoxyglucose uptake was elevated also in this group, despite the fact that gas exchange had not yet deteriorated after 90 min of overdistension alone. Conclusion The authors could detect regional neutrophil activation in VILI even when end-expiratory derecruitment was prevented and impairment of gas exchange was not evident. Concomitant end-expiratory derecruitment converted this activation into profound inflammation with decreased aeration and regional shunting.

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Comparison of Linear Poly Ethylene Imine (LPEI) and Poly L-Lysine (PLL) in Fabrication of CHOK1 Cell-Loaded Multilayer Alginate Microcapsules

Advanced Pharmaceutical Bulletin ◽

10.34172/apb.2020.035 ◽

2020 ◽

Vol 10 (2) ◽

pp. 290-296

Author(s):

Fariba Hajifathaliha ◽

Arash Mahboubi ◽

Elham Mohit ◽

Noushin Bolourchian ◽

Vahid Khalaj ◽

...

Keyword(s):

Cell Viability ◽

Cell Survival ◽

Metabolic Activity ◽

Encapsulation Efficiency ◽

Cell Encapsulation ◽

High Price ◽

Ethylene Imine ◽

Linear Poly ◽

Cellular Metabolic Activity ◽

Poly Ethylene

Purpose: Poly l-lysine (PLL) has been introduced as a strengthening covering layer for alginate microcapsules which are the most convenient way for cell encapsulation. Some disadvantages of PLL such as high price and low biocompatibility have prompted scientists to find better alternatives. Linear poly ethylene imine (LPEI), thanks to its highly similar structure to PLL, could be considered as a proper cost-effective alternative. In this study LPEI and PLL were compared as covering layers of cell-loaded alginate-LPEI-alginate (cALA) and alginate-PLL-alginate (cAPA) microcapsules. Methods: In addition to the physico-mechanical properties, the encapsulation efficiency, cell survival post encapsulation, cell viability, and cellular metabolic activity within the microcapsules were evaluated using trypan blue, live/dead cell staining, and MTT test, respectively. Results: Physico-mechanical evaluation of the microcapsules revealed that the cell microencapsulation process did not affect their shape, size, and mechanical stability. Although the encapsulation efficiency for cALA and cAPA was not different (P>0.05), cell survival post encapsulation was higher in cALA than in cAPA (P<0.05) which could be the reason for the higher cell viability and also cellular metabolic activity within these microcapsules in comparison to cAPA. Conclusion: Here, based on these results, ALA could be introduced as a preferable alternative to APA for cell encapsulation.

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Tracking the degradation of polysaccharide hydrogels by non-invasive near-infrared fluorescence imaging

Osteoarthritis and Cartilage ◽

10.1016/j.joca.2016.01.294 ◽

2016 ◽

Vol 24 ◽

pp. S150

Author(s):

Y. Fu ◽

R. Wang ◽

S. Both ◽

P. Dijkstra ◽

M. Karperien

Keyword(s):

Fluorescence Imaging ◽

Near Infrared ◽

Near Infrared Fluorescence ◽

Non Invasive ◽

Near Infrared Fluorescence Imaging

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Multidimensional Fluorescence Imaging for Non-Invasive Tracking of Cell Responses

Molecular Nano Dynamics ◽

10.1002/9783527627820.ch32 ◽

2009 ◽

pp. 623-643

Author(s):

Ryosuke Nakamura ◽

Yasuo Kanematsu

Keyword(s):

Fluorescence Imaging ◽

Non Invasive ◽

Cell Responses ◽

Multidimensional Fluorescence

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Fluorescence Imaging as a Non-Invasive Technology to Monitor the Performance of Glyphosate Adjuvants and Formulations

Pesticide Formulations and Delivery Systems, 27th Volume: Traditional and Non-Traditional Developments ◽

10.1520/stp47511s ◽

2009 ◽

pp. 87-87-8

Author(s):

H. de Ruiter ◽

B. Mack ◽

R. van der Schoor ◽

H. Jalink

Keyword(s):

Fluorescence Imaging ◽

Non Invasive

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Bacteria Death and Osteoblast Metabolic Activity Correlated to Hydrothermally Synthesised TiO2 Surface Properties

Molecules ◽

10.3390/molecules24071201 ◽

2019 ◽

Vol 24 (7) ◽

pp. 1201 ◽

Cited By ~ 2

Author(s):

Alka Jaggessar ◽

Asha Mathew ◽

Tuquabo Tesfamichael ◽

Hongxia Wang ◽

Cheng Yan ◽

...

Keyword(s):

Contact Angle ◽

Surface Properties ◽

Metabolic Activity ◽

Mechanical Stability ◽

Antibacterial Properties ◽

Mechanical Tests ◽

Nanostructured Surfaces ◽

Surface Contact Angle ◽

Cellular Metabolic Activity ◽

Structure Height

Orthopaedic surgery comes with an inherent risk of bacterial infection, prolonged antibiotic therapy and revision surgery. Recent research has focused on nanostructured surfaces to improve the bactericidal and osseointegrational properties of implants. However, an understanding of the mechanical properties of bactericidal materials is lacking. In this work, the surface properties of hydrothermal TiO2 nanostructured surfaces are investigated for their effect on bactericidal efficiency and cellular metabolic activity of human osteoblast cells. TiO2 nanostructures, approximately 307 nm in height and 14 GPa stiffness, were the most effective structures against both gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria. Statistical analysis significantly correlated structure height to the death of both bacteria strains. In addition, the surface contact angle and Young’s modulus were correlated to osteoblast metabolic activity. Hydrophilic surfaces with a contact angle between 35 and 50° produced the highest cellular metabolic activity rates after 24 hours of incubation. The mechanical tests showed that nanostructures retain their mechanical stability and integrity over a long time-period, reaffirming the surfaces’ applicability for implants. This work provides a thorough examination of the surface, mechanical and wettability properties of multifunctional hydrothermally synthesised nanostructured materials, capable of killing bacteria whilst improving osteoblast metabolic rates, leading to improved osseointegration and antibacterial properties of orthopaedic implants.

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