Review of the fluid flow within intervertebral discs - How could in vitro measurements replicate in vivo?

2016 ◽  
Vol 49 (14) ◽  
pp. 3133-3146 ◽  
Author(s):  
Hendrik Schmidt ◽  
Sandra Reitmaier ◽  
Friedmar Graichen ◽  
Aboulfazl Shirazi-Adl
Keyword(s):  
Fluid Flow ◽  
Intervertebral Discs ◽  
In Vitro Measurements

scholarly journals O23: CHARACTERISING PATIENT-DERIVED COLORECTAL CANCER TISSUE-ORIGINATED ORGANOIDAL SPHEROIDS FOR HIGH-THROUGHPUT MICROFLUIDIC APPLICATIONS

2021 ◽  
Vol 108 (Supplement_1) ◽  
Author(s):  
MI Khot ◽  
M Levenstein ◽  
R Coppo ◽  
J Kondo ◽  
M Inoue ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Fluid Flow ◽  
High Throughput ◽  
Microfluidic Devices ◽  
In Vitro Models ◽  
Fluorescent Imaging ◽  
Cancer Tissue ◽  
Cell Models

Abstract Introduction Three-dimensional (3D) cell models have gained reputation as better representations of in vivo cancers as compared to monolayered cultures. Recently, patient tumour tissue-derived organoids have advanced the scope of complex in vitro models, by allowing patient-specific tumour cultures to be generated for developing new medicines and patient-tailored treatments. Integrating 3D cell and organoid culturing into microfluidics, can streamline traditional protocols and allow complex and precise high-throughput experiments to be performed with ease. Method Patient-derived colorectal cancer tissue-originated organoidal spheroids (CTOS) cultures were acquired from Kyoto University, Japan. CTOS were cultured in Matrigel and stem-cell media. CTOS were treated with 5-fluorouracil and cytotoxicity evaluated via fluorescent imaging and ATP assay. CTOS were embedded, sectioned and subjected to H&E staining and immunofluorescence for ABCG2 and Ki67 proteins. HT29 colorectal cancer spheroids were produced on microfluidic devices using cell suspensions and subjected to 5-fluorouracil treatment via fluid flow. Cytotoxicity was evaluated through fluorescent imaging and LDH assay. Result 5-fluorouracil dose-dependent reduction in cell viability was observed in CTOS cultures (p<0.01). Colorectal CTOS cultures retained the histology, tissue architecture and protein expression of the colonic epithelial structure. Uniform 3D HT29 spheroids were generated in the microfluidic devices. 5-fluorouracil treatment of spheroids and cytotoxic analysis was achieved conveniently through fluid flow. Conclusion Patient-derived CTOS are better complex models of in vivo cancers than 3D cell models and can improve the clinical translation of novel treatments. Microfluidics can streamline high-throughput screening and reduce the practical difficulties of conventional organoid and 3D cell culturing. Take-home message Organoids are the most advanced in vitro models of clinical cancers. Microfluidics can streamline and improve traditional laboratory experiments.

scholarly journals The pathophysiologic role of the protein kinase Cδ pathway in the intervertebral discs of rabbits and mice: In vitro, ex vivo, and in vivo studies

2012 ◽  
Vol 64 (6) ◽  
pp. 1950-1959 ◽  
Author(s):  
Michael B. Ellman ◽  
Jae-Sung Kim ◽  
Howard S. An ◽  
Jeffrey S. Kroin ◽  
Xin Li ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Ex Vivo ◽  
Intervertebral Discs ◽  
In Vivo Studies ◽  
Protein Kinase Cδ

In Vitro Experimental Investigation of the Integrity of the Stem–Cement Interface

2013 ◽  
Vol 647 ◽  
pp. 53-56
Author(s):  
Hong Yu Zhang ◽  
Leigh Fleming ◽  
Liam Blunt
Keyword(s):  
Experimental Investigation ◽  
Fluid Flow ◽  
Hip Replacement ◽  
Hip Prosthesis ◽  
Vitro Experiment ◽  
Cement Interface ◽  
In Vitro Experiment ◽  
Mechanical Bonding

The rationale behind failure of cemented total hip replacement is still far from being well understood in a mechanical and molecular perspective. In the present study, the integrity of the stem–cement interface was investigated through an in vitro experiment monitoring fluid flow along this interface. The results indicated that a good mechanical bonding formed at the stem–cement interface before debonding of this interface was induced by physiological loadings during the in vivo service of the hip prosthesis.

Correlation of in vivo and in vitro measurements of sun protection factor

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
M.-T. Sheu ◽  
C.-W. Lin ◽  
M.-C. Huang ◽  
C.-H. Shen ◽  
H.-O. Ho
Keyword(s):  
Sun Protection ◽  
Protection Factor ◽  
In Vitro Measurements ◽  
Sun Protection Factor

scholarly journals Advances in Photoacoustic Noninvasive Glucose Testing

1999 ◽  
Vol 45 (9) ◽  
pp. 1587-1595 ◽  
Author(s):  
Hugh A MacKenzie ◽  
Helen S Ashton ◽  
Stephen Spiers ◽  
Yaochun Shen ◽  
Scott S Freeborn ◽  
...  
Keyword(s):  
Glucose Measurement ◽  
Oral Glucose ◽  
Physiological Factors ◽  
Glucose Testing ◽  
In Vivo Experiments ◽  
In Vitro Measurements ◽  
Clinical Measurements ◽  
Blood Analytes

Abstract We report here on in vitro and in vivo experiments that are intended to explore the feasibility of photoacoustic spectroscopy as a tool for the noninvasive measurement of blood glucose. The in vivo results from oral glucose tests on eight subjects showed good correlation with clinical measurements but indicated that physiological factors and person-to-person variability are important. In vitro measurements showed that the sensitivity of the glucose measurement is unaffected by the presence of common blood analytes but that there can be substantial shifts in baseline values. The results indicate the need for spectroscopic data to develop algorithms for the detection of glucose in the presence of other analytes.

scholarly journals Intraperitoneal pressure: Stability over time and validation of Durand’s measurement method

2020 ◽  
pp. 089686082097312
Author(s):  
Alicia Sobrino-Pérez ◽  
Alfonso Pérez-Escudero ◽  
Lucila Fernández-Arroyo ◽  
Ana Dorado-García ◽  
Berta Martín-Alcón ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Venous Pressure ◽  
Relevant Parameter ◽  
Pressure System ◽  
Intraperitoneal Pressure ◽  
In Vitro Measurements ◽  
Long Timescales ◽  
Over Time

Intraperitoneal pressure (IPP) is gaining consideration as a relevant parameter of peritoneal dialysis (PD) in adults, although many of its aspects are still pending clarification. We address here its stability over time and the validity of the usual method of clinical measurement, as proposed by Durand in 1992 but never specifically validated. We performed this validation by comparing Durand’s method and direct measurements with a central venous pressure system. We performed a total of 250 measurement pairs in 50 patients with different intraperitoneal volumes plus in-vitro measurements with a simulated peritoneum. Absolute differences between the two systems in vivo were 0.87 ± 0.91 cmH2O (range 0–5 cmH2O); only 6.4% of them were ≥3 cmH2O. In vitro results for both methods were identical. We also compared IPP measurements in the same patient separated by 1–4 h (514 measurement pairs in 136 patients), 1 week (92 pairs in 92 patients), and 2 years (34 pairs in 17 patients). Net differences of measurements separated by hours or 1 week were close to 0 cmH2O, with oscillations of 1.5 cmH2O in hours and 2.3 cmH2O in 1 week. IPP measured 2 years apart presented a net decrease of 2.5 ± 4.9 cmH2O, without correlation with body mass index changes or any other usual parameter of PD. In hours, 7% of IPP differences were >3 cmH2O, 22% in 1 week, and 50% in 2 years. In conclusion, Durand’s method is precise enough to measure IPP in peritoneal dialysis. This parameter is not stable over long timescales, so it is necessary to use recent measurements.

In Vivo Compliance of the Human Saphenous Vein Measured by Sonography: Comparison with Plethysmographic and in vitro Measurements

1995 ◽  
Vol 10 (4) ◽  
pp. 143-148 ◽  
Author(s):  
G. Lefthériotis ◽  
Th. Pochet ◽  
P. Abraham ◽  
J. B. Subayi-Kamuanga ◽  
A. Jardel ◽  
...  
Keyword(s):  
Saphenous Vein ◽  
Bypass Surgery ◽  
Coronary Bypass ◽  
Coronary Bypass Surgery ◽  
University Hospital ◽  
Human Saphenous Vein ◽  
Venous Compliance ◽  
In Vitro Measurements

Objective: To evaluate a non-invasive and selective measurement of in vivo venous compliance of the human saphenous vein using sonography. Design: An experimental study in patients prior to coronary bypass surgery. Setting: Departments of Physiology and Cardiothoracic Surgery, University Hospital of Angers. Patients: Thirty patients investigated prior to coronary bypass surgery. Interventions: Simultaneous strain-gauge venous occlusion plethysmography (VOP) and measurements of the circumference of the great saphenous vein by sonography at four different occlusion pressures: 20, 30, 40 and 50 mmHg. In 10 of the same patients, in vitro determination of pressure–volume relationship during progressive inflation of excised saphenous vein samples. Main outcome measures: Venous compliance obtained with the three methods. Results: Weak correlation coefficients were found between in vitro measurements and VOP ( r=0.478, p<0.01) and sonography ( r=0.497, p<0.02). Although individual correlations between in vitro and VOP measurements ranged from 0.928 to 0.999, a wide heterogeneity was found with sonography (from 0.620 to 0.985). Conclusions: Sonography allows the selective measurement of in vivo venous compliance, although the measured compliances differ from other techniques.

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