Comparison of Centrifugal and Pulsatile Perfusion to Preserve Donor Kidneys Using Ex Vivo Subnormothermic Perfusion

2021 ◽  
pp. 1-7
Author(s):  
Patrick P. W. Luke ◽  
Larry Jiang ◽  
Aushanth Ruthirakanthan ◽  
Daniel Lee ◽  
Qizhi Sun ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Pulsatile Perfusion

Maximal Cord Blood Recovery and CD34+ Progenitor Cell Collection Using Machine Pulsatile Perfusion of Placentas.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3643-3643 ◽  
Author(s):  
Thomas A. Davis ◽  
Fred Gage
Keyword(s):  
Cord Blood ◽  
Umbilical Cord ◽  
Progenitor Cell ◽  
Ex Vivo ◽  
Median Number ◽  
Low Density ◽  
Canine Heart ◽  
Cell Content ◽  
Hematopoietic Stem ◽  
Pulsatile Perfusion

Abstract Umbilical cord blood (UCB) is an attractive source of hematopoietic stem cells (HSC) because of greater availability, less stringent HLA matching requirements, and lower incidence and severity of GVHD. Currently, UCB transplant procedures in adults are limited by low collection volumes of total nucleated cells and CD34+ HSC. Approaches to ex vivo expand long-term engraftable HSC have been widely unsuccessful. Recent studies have clearly demonstrated that infusion of a greater number of cells UCB cells enhances the rate of engraftment and lowers the risk of transplantation-related mortality. Machine pulsatile perfusion (MPP) has been successfully used to select cadaveric renal allografts for transplantation, to isolate human islets from pancreata and shown to be a useful cardiac preservation technique in canine heart transplant studies. In this study, the feasibility of using machine pulsatile perfusion to collect human UCB total nucleated cells and CD34+ HSCs was evaluated using placentas designated for research purposes. Immediately following delivery UCB (65 ± 15 mL, n=5) was first collected by needle aspiration from the umbilical cord vein in accordance with standard procedures then followed by MPP (~500 ml) of the placental arteries within 2–3 hours of delivery. Clinically total nucleated cells count (TNC), CD34+ cell numbers and myeloid, erythroid and multipotent CFU progenitor cell content of UCB units are used as predictive measurements of hematopoietic/engraftment potential. Low-density cells (<1.077 g/mL) were isolated by density centrifugation. The median number of viable low density cells obtained was 488 × 106 (range, 240–652 × 106), and 1541 × 106 (range, 888–1800 × 106) for UCB and MPP collections, respectively. MMP low density cell preparations contained significantly more mature segmented neutrophils with a low percentage (<0.1%) of sheared-off vessel wall endothelial cells. Both UCB and MPP low density cells collections showed similar number of assayable CFU-GEMM, CFU-GM, CFU-M, and CFU-G progenitor cells. In contrast, MMP collected cells contained 2–3 times more erythroid BFU-E colonies than UCB collections. Equivalent numbers of CD34+ HSC were enumerated by FACS analysis and subsequently isolated by positive immunomagnetic MACS selection from MPP and UCB collections. Likewise, the progenitor cell content (CFU-GEMM, CFU-GM, CFU-M, CFU-G and BFU-e) of the isolated CD34+ cell populations derived from each cell collection were very similar. These results demonstrate that pulsatile perfusion can be performed easily after traditional UCB collection procedures. This technique effectively recovers on average twice as many TNC and multilineage CD34+ HSC cells when compared to traditional UCB collection procedures. Altogether these results are particular promising since increased numbers of UCB HSC available for infusion should result in accelerated hematopoietic recovery. Moreover, the demonstrated enhanced HSC cell yield together with the simplicity of collection could potentially widen the clinical applicability of UCB transplants in adults.

Pulsatile perfusion system for ex vivo investigation of biochemical pathways in intact vascular tissue

1996 ◽  
Vol 270 (2) ◽  
pp. H760-H768 ◽  
Author(s):  
R. F. Labadie ◽  
J. F. Antaki ◽  
J. L. Williams ◽  
S. Katyal ◽  
J. Ligush ◽  
...  
Keyword(s):  
Vascular Tissue ◽  
Ex Vivo ◽  
Pearson Correlation ◽  
Vessel Diameter ◽  
Perfusion System ◽  
Vascular Perfusion ◽  
Hemodynamic Variables ◽  
Morphological Studies ◽  
Confocal Scanning ◽  
Pulsatile Perfusion

We have constructed and performed initial validation of an innovative perfusion system that allows exposure of intact segments of vascular tissue to realistic physiological and hemodynamic environments ex vivo. Computer-controlled opening and closing of an in-line gate valve allows generation of arterial pressure waveforms. The control algorithm predicted resultant pressure waveforms with a high degree of accuracy (Pearson correlation coefficient > 0.97). To document vascular homeostasis ex vivo, vasomotor bioassays and morphological studies were performed. The bioassays consisted of injecting epinephrine (2 x 10(-3) mg/ml) into the perfusion system followed by acetylcholine (100 microM) while concurrently measuring vessel diameter with a laser micrometer, significant vasomotion was measured for canine carotid arteries (n = 4) bioassayed after 1, 24, and 48 h of perfusion (P < 0.03). Additionally, human saphenous vein segments were perfused for 24 h (n = 4) and viewed with laser confocal scanning microscopy and transmission electron microscopy; photomicrographs show typical vascular morphology. We conclude that the vascular perfusion system described herein is well suited for investigating the response of intact vascular tissue to hemodynamic variables.

Ultrastructural Changes of Canine Kidneys During 24-Hour Perfusion on a LI-400 Preservation System

1971 ◽  
Vol 29 ◽  
pp. 316-317
Author(s):  
M. O. Magnusson ◽  
D. G. Osborne ◽  
T. Shimoji ◽  
W. S. Kiser ◽  
W. A. Hawk
Keyword(s):  
Electron Microscopy ◽  
Electrolyte Solution ◽  
Ultrastructural Changes ◽  
Midline Incision ◽  
Short Term ◽  
Pentobarbital Anesthesia ◽  
Pulsatile Perfusion

Short term experimental and clinical preservation of kidneys is presently best accomplished by hypothermic continuous pulsatile perfusion with cryoprecipitated and millipore filtered plasma. This study was undertaken to observe ultrastructural changes occurring during 24-hour preservation using the above mentioned method.A kidney was removed through a midline incision from healthy mongrel dogs under pentobarbital anesthesia. The kidneys were flushed immediately after removal with chilled electrolyte solution and placed on a LI-400 preservation system and perfused at 8-10°C. Serial kidney biopsies were obtained at 0-½-1-2-4-8-16 and 24 hours of preservation. All biopsies were prepared for electron microscopy. At the end of the preservation period the kidneys were autografted.

Correlation of γ-radioactivity and Scanning Electron Microscopy in measurement of retention of 111Indium-labeled canine endothelial cells on synthetic vascular grafts

1989 ◽  
Vol 47 ◽  
pp. 886-887
Author(s):  
E.J. Prendiville ◽  
S. Laliberté Verdon ◽  
K. E. Gould ◽  
K. Ramberg ◽  
R. J. Connolly ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ex Vivo ◽  
Vascular Grafts ◽  
Retention Data ◽  
Vascular Prostheses ◽  
Group 4 ◽  
Human Fibronectin ◽  
Insufficient Time ◽  
Group 3 ◽  
Group 2

Endothelial cell (EC) seeding is postulated as a mechanism of improving patency in small caliber vascular grafts. However the majority of seeded EC are lost within 24 hours of restoration of blood flow in previous canine studies . We postulate that the cells have insufficient time to fully develop their attachment to the graft surface prior to exposure to hemodynamic stress. We allowed EC to incubate on fibronectin-coated ePTFE grafts for four different time periods after seeding and measured EC retention after perfusion in a canine ex vivo shunt circuit.Autologous canine EC, were enzymatically harvested, grown to confluence, and labeled with 30 μCi 111 Indium-oxine/80 cm 2 flask. Four groups of 5 cm x 4 mm ID ePTFE vascular prostheses were coated with 1.5 μg/cm.2 human fibronectin, and seeded with 1.5 x 105 EC/ cm.2. After seeding grafts in Group 1 were incubated in complete growth medium for 90 minutes, Group 2 were incubated for 24 hours, Group 3 for 72 hours and Group 4 for 6 days. Grafts were then placed in the canine ex vivo circuit, constructed between femoral artery and vein, and subjected to blood flow of 75 ml per minute for 6 hours. Continuous counting of γ-activity was made possible by placing the seeded graft inside the γ-counter detection crystal for the duration of perfusion. EC retention data after 30 minutes, 2 hours and 6 hours of flow are shown in the table.

Elevated level of circulatory sTLT1 induces inflammation through SYK/MEK/ERK signalling in coronary artery disease

2019 ◽  
Vol 133 (22) ◽  
pp. 2283-2299
Author(s):  
Apabrita Ayan Das ◽  
Devasmita Chakravarty ◽  
Debmalya Bhunia ◽  
Surajit Ghosh ◽  
Prakash C. Mandal ◽  
...  
Keyword(s):  
Risk Factors ◽  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Chronic Inflammation ◽  
Ex Vivo ◽  
Human Subjects ◽  
Critical Role ◽  
Atherosclerotic Cardiovascular Disease ◽  
Tnf Α ◽  
Artery Disease

Abstract The role of inflammation in all phases of atherosclerotic process is well established and soluble TREM-like transcript 1 (sTLT1) is reported to be associated with chronic inflammation. Yet, no information is available about the involvement of sTLT1 in atherosclerotic cardiovascular disease. Present study was undertaken to determine the pathophysiological significance of sTLT1 in atherosclerosis by employing an observational study on human subjects (n=117) followed by experiments in human macrophages and atherosclerotic apolipoprotein E (apoE)−/− mice. Plasma level of sTLT1 was found to be significantly (P<0.05) higher in clinical (2342 ± 184 pg/ml) and subclinical cases (1773 ± 118 pg/ml) than healthy controls (461 ± 57 pg/ml). Moreover, statistical analyses further indicated that sTLT1 was not only associated with common risk factors for Coronary Artery Disease (CAD) in both clinical and subclinical groups but also strongly correlated with disease severity. Ex vivo studies on macrophages showed that sTLT1 interacts with Fcɣ receptor I (FcɣRI) to activate spleen tyrosine kinase (SYK)-mediated downstream MAP kinase signalling cascade to activate nuclear factor-κ B (NF-kB). Activation of NF-kB induces secretion of tumour necrosis factor-α (TNF-α) from macrophage cells that plays pivotal role in governing the persistence of chronic inflammation. Atherosclerotic apoE−/− mice also showed high levels of sTLT1 and TNF-α in nearly occluded aortic stage indicating the contribution of sTLT1 in inflammation. Our results clearly demonstrate that sTLT1 is clinically related to the risk factors of CAD. We also showed that binding of sTLT1 with macrophage membrane receptor, FcɣR1 initiates inflammatory signals in macrophages suggesting its critical role in thrombus development and atherosclerosis.

The Shikani HME: A New Tracheostomy Heat and Moisture Exchanger

2020 ◽  
Vol 63 (9) ◽  
pp. 2921-2929
Author(s):  
Alan H. Shikani ◽  
Elamin M. Elamin ◽  
Andrew C. Miller
Keyword(s):  
Ex Vivo ◽  
Moisture Loss ◽  
Speaking Valve ◽  
Time Zero ◽  
In Series ◽  
Turbulent Airflow ◽  
The Difference ◽  
Loss Efficiency ◽  
Heat And Moisture ◽  
Lung Simulation

Purpose Tracheostomy patients face many adversities including loss of phonation and essential airway functions including air filtering, warming, and humidification. Heat and moisture exchangers (HMEs) facilitate humidification and filtering of inspired air. The Shikani HME (S-HME) is a novel turbulent airflow HME that may be used in-line with the Shikani Speaking Valve (SSV), allowing for uniquely preserved phonation during humidification. The aims of this study were to (a) compare the airflow resistance ( R airflow ) and humidification efficiency of the S-HME and the Mallinckrodt Tracheolife II tracheostomy HME (M-HME) when dry (time zero) and wet (after 24 hr) and (b) determine if in-line application of the S-HME with a tracheostomy speaking valve significantly increases R airflow over a tracheostomy speaking valve alone (whether SSV or Passy Muir Valve [PMV]). Method A prospective observational ex vivo study was conducted using a pneumotachometer lung simulation unit to measure airflow ( Q ) amplitude and R airflow , as indicated by a pressure drop ( P Drop ) across the device (S-HME, M-HME, SSV + S-HME, and PMV). Additionally, P Drop was studied for the S-HME and M-HME when dry at time zero (T 0 ) and after 24 hr of moisture testing (T 24 ) at Q of 0.5, 1, and 1.5 L/s. Results R airflow was significantly less for the S-HME than M-HME (T 0 and T 24 ). R airflow of the SSV + S-HME in series did not significant increase R airflow over the SSV or PMV alone. Moisture loss efficiency trended toward greater efficiency for the S-HME; however, the difference was not statistically significant. Conclusions The turbulent flow S-HME provides heat and moisture exchange with similar or greater efficacy than the widely used laminar airflow M-HME, but with significantly lower resistance. The S-HME also allows the innovative advantage of in-line use with the SSV, hence allowing concurrent humidification and phonation during application, without having to manipulate either device.

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