scholarly journals In Depth Flow Inspection Using Dynamic Laser Speckle Temporal Statistics

2019 ◽  
Author(s):  
Mark Golberg ◽  
Ran Califa ◽  
Sagi Polani ◽  
Javier Garcia ◽  
Zeev Zalevsky

AbstractWe present novel optical approach based on statistical analysis of temporal laser speckle patterns for tissue in-depth flow characteristics. An ability to distinguish between Brownian motion of particles and laminar flow is well proved. The main steps in the post processing algorithm and the in-vivo and in-vitro experimental results are presented and demonstrated.

2020 ◽  
Vol 17 (3) ◽  
pp. 207-217
Author(s):  
Eman A. Hakeem ◽  
Galal M. El-Mahrouk ◽  
Ghada Abdelbary ◽  
Mahmoud H. Teaima

Background: Clopidogrel (CLP) suffers from extensive first pass metabolism results in a negative impact on its oral systemic bioavailability. Cubosomes are Lyotropic Liquid Crystalline (LLC) nano-systems comprising monoolein, a steric stabilizer and an aqueous system, it considered a promising carrier for different pharmaceutical compounds. Box-Behnken Design (BBD) is an efficient tool for process analysis and optimization skipping forceful treatment combinations. Objective: The study was designed to develop freeze-dried clopidogrel loaded LLC (cubosomes) for enhancement of its oral bioavailability. Methods: A 33 BBD was adopted, the studied independent factors were glyceryl monooleate (GMO lipid phase), Pluronic F127 (PL F127steric stabilizer) and polyvinyl alcohol powder (stabilizer). Particle Size (PS), Polydispersity Index (PDI) and Zeta Potential (ZP) were set as independent response variables. Seventeen formulae were prepared in accordance with the bottom up approach and in-vitro evaluated regarding PS, PDI and ZP. Statistical analysis and optimization were achieved using design expert software®, then the optimum suggested formula was prepared, in-vitro revaluated, freeze-dried with 3% mannitol (cryoprotectant), solid state characterized and finally packed in hard gelatin capsule for comparative in-vitro release and in-vivo evaluation to Plavix®. Results: Results of statistical analysis of each individual response revealed a quadratic model for PS and PDI where a linear model for ZP. The optimum suggested formula with desirability factor equal 0.990 consisting of (200 mg GMO, 78.15 mg PL F127 and 2% PVA). LC/MS/MS study confirmed significant higher C>max, AUC>0-24h and AUC>0-∞ than that of Plavix®. Conclusion: The results confirm the capability of developed carrier to overcome the low oral bioavailability.


2021 ◽  
Author(s):  
Belén Casas ◽  
Liisa Vilén ◽  
Sophie Bauer ◽  
Kajsa Kanebratt ◽  
Charlotte Wennberg Huldt ◽  
...  

Microphysiological systems (MPS) are powerful tools for emulating human physiology and replicating disease progression in vitro. MPS could be better predictors of human outcome than current animal models, but mechanistic interpretation and in vivo extrapolation of the experimental results remain significant challenges. Here, we address these challenges using an integrated experimental-computational approach. This approach allows for in silico representation and predictions of glucose metabolism in a previously reported MPS with two organ compartments (liver and pancreas) connected in a closed loop with circulating medium. We developed a computational model describing glucose metabolism over 15 days of culture in the MPS. The model was calibrated on an experiment-specific basis using data from seven experiments, where single-liver or liver-islet cultures were exposed to both normal and hyperglycemic conditions resembling high blood glucose levels in diabetes. The calibrated models reproduced the fast (i.e. hourly) variations in glucose and insulin observed in the MPS experiments, as well as the long-term (i.e. over weeks) decline in both glucose tolerance and insulin secretion. We also investigated the behavior of the system under hypoglycemia by simulating this condition in silico, and the model could correctly predict the glucose and insulin responses measured in new MPS experiments. Last, we used the computational model to translate the experimental results to humans, showing good agreement with published data of the glucose response to a meal in healthy subjects. The integrated experimental-computational framework opens new avenues for future investigations toward disease mechanisms and the development of new therapies for metabolic disorders.


2015 ◽  
Vol 8 (9) ◽  
pp. 969-972 ◽  
Author(s):  
Frank Lally ◽  
Mitra Soorani ◽  
Timothy Woo ◽  
Sanjeev Nayak ◽  
Changez Jadun ◽  
...  

BackgroundMechanical thrombectomy with stent retriever devices is associated with significantly better outcomes than thrombolysis alone in the treatment of acute ischemic stroke. Thrombus aspiration achieves high patency rates, but clinical outcomes are variable. The aim of this study was to examine the effect of different suction conditions on perfusate flow during aspiration thrombectomy.MethodsA computational fluid dynamics model of an aspiration device within a patent and occluded blood vessel was used to simulate flow characteristics using fluid flow solver software. A physical particulate flow model of a patent vessel and a vessel occluded by thrombus was then used to visualize flow direction and measure flow rates with the aspiration catheter placed 1–10 mm proximal of the thrombus, and recorded on video.ResultsThe mathematical model predicted that, in a patent vessel, perfusate is drawn from upstream of the catheter tip while, in an occluded system, perfusate is drawn from the vessel proximal to the device tip with no traction on the occlusion distal of the tip. The in vitro experiments confirmed the predictions of this model. In the occluded vessel aspiration had no effect on the thrombus unless the tip of the catheter was in direct contact with the thrombus.ConclusionsThese experiments suggest that aspiration is only effective if the catheter tip is in direct contact with the thrombus. If the catheter tip is not in contact with the thrombus, aspirate is drawn from the vessels proximal of the occlusion. This could affect collateral flow in vivo.


Author(s):  
Rituraj Niranjan ◽  
Muthukumaravel Subramanian ◽  
Devaraju Panneer ◽  
Sanjay Kumar Ojha

Background: Diesel exhaust particulates (DEPs) affect lung physiology and cause serious damage to the lungs. A number of studies demonstrated that, eosinophils play a very important role in the development of tissue remodelling and fibrosis of lungs. However, the exact mechanism of pathogenesis of tissue remodelling and fibrosis is not known. Methods: Both in vitro and in vivo models were used in the study. HL-60 and A549 cells were used in the study. Balb/C mice of 8 to 12 weeks old were used for in vivo study. Cell viability by MTT assay, RNA isolation by tri reagent was accomplished. mRNA expression of inflammatory genes were accomplished by real time PCR or qPCR. Immunohistochemistry was done to asses the localization and expressions of proteins. One way ANOVA followed by post hoc test were done for the statistical analysis. Graph-Pad Prism software was used for statistical analysis. Results: We for the first time demonstrate that, Interleukin-13 plays a very important role in the development of tissue remodelling and fibrosis. We report that, diesel exhaust particles significantly induce eosinophils cell proliferation and interleukin-13 release in in vitro culture conditions. Supernatant collected from DEP-induced eosinophils cells significantly restrict cell proliferation of epithelial cells in response to exposure of diesel exhast particles. Furthermore, purified interleukin-13 decreases the proliferation of A549 cells, highliting the involvement of IL-13 in tissue remodeling. Notably, Etoricoxib (selective COX-2 inhibitor) did not inhibit DEP-triggered release of interleukin-13, suggesting another cell signalling pathway. The in vivo exposer of DEP to the lungs of mice, resulted in high level of eosinophils degranulation as depicted by the EPX-1 immunostaining and altered level of mRNA expressions of inflammatory genes. We also found that, a-SMA, fibroblast specific protein (FSP-1) has been changed in response to DEP in the mice lungs along with the mediators of inflammation. Conclusion: Altogether, we elucidated, the mechanistic role of eosinophils and IL-13 in the DEP-triggered proliferation of lungs cells thus providing an inside in the pathophysiology of tissue remodelling and fibrosis of lungs.


2006 ◽  
Vol 18 (2) ◽  
pp. 273
Author(s):  
M. K. Kim ◽  
H. J. Oh ◽  
Y. H. Fibrianto ◽  
G. Jang ◽  
H. J. Kim ◽  
...  

A bitch ovulates a primary oocyte that undergoes both maturation and fertilization within the oviduct fluid for 3 days. In an attempt to define the physiologically appropriate conditions for oocyte maturation in the bitch, in vitro conditions based upon the oviductal environment need to be established. The present study was conducted to develop canine synthetic oviduct fluid (cSOF) by investigating the composition of canine oviduct fluid, follicular fluid, and bursa fluid. The bursa and oviduct fluid were collected at Days 1 and 3 of ovulation, respectively. Before ovulation, follicles were punched and the fluid was collected by aspiration. Biochemical parameters (Ca, P, Mg, albumin, total protein, and glucose) were measured using a chromatographic enzymic method. Quantitative determination of electrolytes (Na, Cl, K) concentration in the follicular, bursa, and oviductal fluids was performed using an Electrolyte 5 Analyzer (Nora Biomedical, Waltham, MA, USA). The concentrations of sodium, potassium, and chloride were similar among oviduct (153.5, 5.2, and 121.5 mmol/L, respectively), bursa (149.5, 4.3, and 123 mmol/L, respectively), and follicular (147, 4.2, and 120.5 mmol/L, respectively) fluids. Glucose concentration was different in oviduct, bursa, and follicular fluids (1.09, 3.75, and 3.94 mmol/L, respectively). Total protein and magnesium concentrations were not different among the three fluids, but phosphorus concentration differed in oviduct, bursa, and follicular fluids (0.001, 0.044, and 0.024 g/L, respectively). The oviduct fluid showed lower concentrations of albumin and calcium (0.001 g/L and 1.372 mmol/L, respectively) compared to bursa (0.023 g/L and 2.532 mmol/L, respectively) or follicular fluid (0.025 g/L and 2.632 mmol/L, respectively). The cSOF1 and cSOF2 were developed on the basis of the oviduct and follicular fluids, respectively. Canine oocytes were recovered by slicing ovaries collected after ovariohysterectomy in bitches at follicular stages, and in vitro nuclear maturation of canine oocytes cultured in cSOF1 or cSOF2 were compared to that of intra-oviduct (in vivo) culture. For in vivo culture, the canine oocytes were transferred and cultured in intra-oviduct for 72 h and were recovered by intra-oviduct flushing using surgical methods. For in vitro culture, canine oocytes were cultured in cSOF1, cSOF2, or TCM-199 (control) for 72 h at 38.5�C in a humidified atmosphere of 5% CO2 in air. The experiment was replicated three times and statistical analysis was carried out by ANOVA with GLMs in the statistical analysis system program (SAS Institute, Inc., Cary, NC, USA). Nuclear maturation of canine oocytes to MII was not different in cSOF1, cSOF2, or intra-oviduct (2.5%, 2.5%, and 2.2%, respectively) compared to the control (1.6%). However, the degeneration rates were significantly higher in oocytes cultured in intra-oviduct (48.2%) compared to control, cSOF1, and cSOF2 (1.6%, 6.8%, and 7.5%, respectively). In conclusion, the present study analyzed the components of the oviduct, bursa, and follicular fluids and developed two canine synthetic oviduct fluids (cSOF1 and 2). In addition, the present study demonstrated that cSOFs can be used for in vitro maturation of canine oocytes.


2013 ◽  
Vol 38 (24) ◽  
pp. 5334 ◽  
Author(s):  
M. Nemati ◽  
R. W. C. G. R. Wijshoff ◽  
J. M. A. Stijnen ◽  
S. van Tuijl ◽  
J. W. M. Bergmans ◽  
...  

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