Visualization of Endothelial Cell Structure During Machine Perfusion Preservation of Livers

2002 ◽  
Author(s):  
Shailendra Jain ◽  
Saurin Purohit ◽  
Jian Zhang ◽  
Mark G. Clemens ◽  
Charles Y. Lee
Keyword(s):  
Confocal Microscopy ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Cell Structure ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Machine Perfusion ◽  
Success Rates ◽  
University Of Wisconsin ◽  
Heart Beating

The development of machine perfusion preservation (MPP) of kidney has led to significant improvements and greater success rates in kidney transplantation by providing superior preserved tissue and viable non-heart-beating donor tissue. However, machine perfusion of livers has not been successful in improving preservation. Currently, the major cause of damage associated with MPP of livers remains unclear. Previous studies showed increased vascular resistance and blockages during and after 24hrs MPP but no direct evidence existed. Utilizing a novel two colors fluorophores labeling, an intravital microscopic study was conducted to obtain real time images and confocal microscopy to get detailed images in order to correlate fluorescent-tagged endothelial cells (ECs) with red cell stasis. Fluorescein isothiocynate (FITC) was used to label red blood cells (RBCs) and DiI acetylated low-density lipoprotein (DiI acLDL) was used to mark ECs. Structure of ECs was recorded and assessed during 24hrs MPP with University of Wisconsin (UW) solution at 4°C with a flow rate of 4ml/min. Images recorded from intravital microscopy and confocal microscopy show ECs rounding over a period of 24 hrs and subsequent red blood cells stasis after 24hrs MPP and during rewarming.

scholarly journals Protective Effect of Pitao (Pitavia punctata (R. & P.) Molina) Polyphenols against the Red Blood Cells Lipoperoxidation and the In Vitro LDL Oxidation

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Ricardo I. Castro ◽  
Oscar Forero-Doria ◽  
Luis Soto-Cerda ◽  
A. Peña-Neira ◽  
Luis Guzmán
Keyword(s):  
Oxidative Stress ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Hypochlorous Acid ◽  
Low Density Lipoprotein ◽  
Membrane Integrity ◽  
Density Lipoprotein ◽  
Ldl Oxidation ◽  
Quercetin Derivatives

The oxidative stress is characterized by an imbalance between the oxidizing agents and antioxidants; meanwhile, the consumption of antioxidants has been considered as an important tool in the prevention of oxidative stress and its consequences. Pitavia punctata (R. & P.) Molina is an endemic arboreal species from the Chilean Coast Range, in which a large amount of flavonoids has been described. This work focused on characterizing and evaluating, in human erythrocytes, the antioxidant capacity and membrane protection of P. punctata extracts and the in vitro protection of the oxidation of the Low Density Lipoprotein (LDL). The phytochemical screening revealed the presence of Quercetin derivatives and flavonoids, such as (-)-Epicatechin, Kaempferol, and derivatives. The methanolic extract presented an important antioxidant activity, protecting the membrane integrity of the red blood cells against the oxidative damage caused by Hypochlorous acid and inhibiting the oxidation of the LDL lipoprotein.

scholarly journals Engineered red blood cells carrying PCSK9 inhibitors persistently lower LDL and prevent obesity

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259353
Author(s):  
Rhogerry Deshycka ◽  
Valentino Sudaryo ◽  
Nai-Jia Huang ◽  
Yushu Xie ◽  
Liyan Y. Smeding ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Chimeric Protein ◽  
Mouse Bone Marrow ◽  
Glycophorin A ◽  
Low Density ◽  
Hematopoietic Stem

Low plasma levels of Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) are associated with decreased low-density lipoprotein (LDL) cholesterol and a reduced risk of cardiovascular disease. PCSK9 binds to the epidermal growth factor-like repeat A (EGFA) domain of LDL receptors (LDLR), very low-density lipoprotein receptors (VLDLR), apolipoprotein E receptor 2 (ApoER2), and lipoprotein receptor–related protein 1 (LRP1) and accelerates their degradation, thus acting as a key regulator of lipid metabolism. Antibody and RNAi—based PCSK9 inhibitor treatments lower cholesterol and prevent cardiovascular incidents in patients, but their high-cost hampers market penetration. We sought to develop a safe, long-term and one-time solution to treat hyperlipidemia. We created a cDNA encoding a chimeric protein in which the extracellular N- terminus of red blood cells (RBCs) specific glycophorin A was fused to the LDLR EGFA domain and introduced this gene into mouse bone marrow hematopoietic stem and progenitor cells (HSPCs). Following transplantation into irradiated mice, the animals produced RBCs with the EGFA domain (EGFA-GPA RBCs) displayed on their surface. These animals showed significantly reduced plasma PCSK9 (66.5% decrease) and reduced LDL levels (40% decrease) for as long as 12 months post-transplantation. Furthermore, the EGFA- GPA mice remained lean for life and maintained normal body weight under a high-fat diet. Hematopoietic stem cell gene therapy can generate red blood cells expressing an EGFA—glycophorin A chimeric protein as a practical and long-term strategy for treating chronic hyperlipidemia and obesity.

scholarly journals Effect of moringa leaf meal and season on blood and hormonal profile of the pearl guinea fowl (Numida meleagris)

2021 ◽  
Vol 11 (3) ◽  
pp. 078-092
Author(s):  
Poku Jnr PA ◽  
Kagya-Agyemang JK ◽  
Kwenin WKJ ◽  
Bonsu FRK ◽  
Kyere CG
Keyword(s):  
High Density Lipoprotein ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Rainy Season ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Low Density ◽  
Hormonal Profile ◽  
Leaf Meal ◽  
Numida Meleagris

This study was undertaken to determine the effect of moringa leaf meal and season on blood and hormonal profile of the Pearl Guinea fowl (Numida meleagris) in the Middle belt of Ghana. Thirty-two (32) males and one hundred and twenty-eight (128) female Pearl Guinea fowls aged one-day-old were used for the study. A 3 x 4 factorial experimental design was used for the experiment. Data collected were analyzed using General Linear Model (GLM) procedure of Statistical Analysis System (SAS for Windows, version 7) and means were separated by the probability of difference (PDIFF) procedure of SAS (2008). Mean cell volume was highest (175.39 fl) among Guinea fowls fed with diet containing 12 % moringa leaf meal level. Guinea fowls fed with diet containing 15 % moringa leaf meal had the highest (3.44 x1012/L) red blood cells production. Eosinophil level was highest (3.95 x1012/L) among Guinea fowls fed with diet containing 9 % moringa leaf meal. Birds fed with the moringa diets recorded the highest (P= 0.022) WBC values as compared to the control diet. Triglycerides, high density lipoprotein and low-density lipoprotein levels increased (P<0.05) with increasing levels of dietary moringa leaf meal in the diet. The highest (P= 0.0025) level of progesterone was observed among birds fed with diet containing 12 and 15 % moringa leaf meal inclusion levels. The level of sodium was highest (166.69 nmol/l) among Guinea fowls fed with diet containing 12 % moringa leaf meal. The major and minor rainy seasons recorded the highest (P<0.05) mean cell hemoglobin, red blood cells, albumin and oestrogen levels. Platelets, follicle stimulating hormone, luteinizing hormone, prolactin and chlorine levels were highest (P<0.05) in the dry season while basophil level was highest in the major rainy season. Cholesterol, triglycerides, high density lipoprotein, low density lipoprotein and potassium levels were highest (P<0.05) in the major rainy season. This study concludes that feeding Guinea fowls with moringa leaf meal had positive effect on some haematological, biochemical and hormonal parameters.

scholarly journals Engineered Red Blood Cells Carrying PCSK9 Inhibitors Persistently Lower LDL and Prevent Obesity

2020 ◽  
Author(s):  
Rhogerry Deshycka ◽  
Valentino Sudaryo ◽  
Nai-Jia Huang ◽  
Yushu Xie ◽  
Liyan Y. Smeding ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Chimeric Protein ◽  
Mouse Bone Marrow ◽  
Glycophorin A ◽  
Low Density ◽  
Hematopoietic Stem

AbstractLow plasma levels of Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) are associated with decreased low-density lipoprotein (LDL) cholesterol and a reduced risk of cardiovascular disease. PCSK9 binds to the epidermal growth factor-like repeat A (EGFA) domain of LDL receptors (LDLR), very low-density lipoprotein receptors (VLDLR), apolipoprotein E receptor 2 (ApoER2), and lipoprotein receptor–related protein 1 (LRP1) and accelerates their degradation, thus acting as a key regulator of lipid metabolism. Antibody and RNAi - based PCSK9 inhibitor treatments lower cholesterol and prevent cardiovascular incidents in patients, but their high cost hampers market penetration. We sought to develop a safe, long-term and one-time solution to treat hyperlipidemia. We created a cDNA encoding a chimeric protein in which the extracellular N-terminus of glycophorin A was fused to the LDLR EGFA domain and introduced this gene into mouse bone marrow hematopoietic stem and progenitor cells (HSPCs). Following transplantation into irradiated mice, the animals produced red blood cells (RBCs) with the EGFA domain (EGFA-GPA RBCs) displayed on their surface. These animals showed significantly reduced plasma PCSK9 (66.5% decrease) and reduced LDL levels (40% decrease) for as long as 12 months post-transplantation. Furthermore, the EGFA-GPA mice remained lean for life and maintained normal body weight under high-fat diet. Hematopoietic stem cell gene therapy can generate red blood cells expressing an EGFA - glycophorin A chimeric protein as a practical and long-term strategy for treating chronic hyperlipidemia and obesity.

scholarly journals Accounting for red blood cell accessibility reveals distinct invasion strategies inPlasmodium falciparumstrains

2019 ◽  
Author(s):  
Francisco Cai ◽  
Tiffany M. DeSimone ◽  
Elsa Hansen ◽  
Cameron V. Jennings ◽  
Amy K. Bei ◽  
...  
Keyword(s):  
Blood Cell ◽  
Red Blood Cells ◽  
Red Blood Cell ◽  
Blood Cells ◽  
Cell Structure ◽  
Clinical Manifestations ◽  
Parasite Growth ◽  
Invasion Pathways ◽  
Invasion Rate

AbstractThe growth of the malaria parasitePlasmodium falciparumin human blood causes all clinical manifestations of malaria, a process that begins with the invasion of red blood cells. Parasites enter red blood cells using distinct pairs of parasite ligands and host receptors that define particular invasion pathways. Parasite strains have the capacity to switch between invasion pathways. This flexibility is thought to facilitate immune evasion against particular parasite ligands, but may also reflect the fact that red blood cell surfaces are dynamic and composed of heterogeneous invasion targets. Different host genetic backgrounds affecting red blood cell structure have long been recognized to impact parasite growthin vivo, but even within a host, red blood cells undergo dramatic changes in morphology and receptor density as they age. The consequences of these heterogeneities for parasite growthin vivoremain unclear. Here, we measured the ability of laboratory strains ofP. falciparumrelying on distinct invasion pathways to enter red blood cells of different ages. We estimated invasion efficiency while accounting for the fact that even if the red blood cells display the appropriate receptors, not all are physically accessible to invading parasites. This approach revealed a tradeoff made by parasites between the fraction of susceptible cells and their invasion rate into them. We were able to distinguish between “specialist” strains exhibiting high invasion rate in fewer cells versus “generalist” strains invading less efficiently into a larger fraction of cells. We developed a mathematical model to predict that infection with a generalist strain would lead to higher peak parasitemiasin vivowhen compared with a specialist strain with similar overall proliferation rate. Thus, the heterogeneous ecology of red blood cells may play a key role in determining the rate of parasite proliferation between different strains ofP. falciparum.

Transcriptional profile reveals altered hepatic lipid and cholesterol metabolism in hyposulfatemic NaS1 null mice

2006 ◽  
Vol 26 (2) ◽  
pp. 116-124 ◽  
Author(s):  
Paul Anthony Dawson ◽  
Brooke Gardiner ◽  
Sean Grimmond ◽  
Daniel Markovich
Keyword(s):  
Cholesterol Metabolism ◽  
Cell Structure ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Human Growth ◽  
Hepatic Glycogen ◽  
Hepatic Lipid ◽  
Functional Roles ◽  
Cell Defense ◽  
Human Growth And Development

Sulfate plays an essential role in human growth and development, and its circulating levels are maintained by the renal Na+-SO42− cotransporter, NaS1. We previously generated a NaS1 knockout ( Nas1−/−) mouse, an animal model for hyposulfatemia, that exhibits reduced growth and liver abnormalities including hepatomegaly. In this study, we investigated the hepatic gene expression profile of Nas1−/− mice using oligonucleotide microarrays. The mRNA expression levels of 92 genes with known functional roles in metabolism, cell signaling, cell defense, immune response, cell structure, transcription, or protein synthesis were increased ( n = 51) or decreased ( n = 41) in Nas1−/− mice when compared with Nas1+/+ mice. The most upregulated transcript levels in Nas1−/− mice were found for the sulfotransferase genes, Sult3a1 (≈500% increase) and Sult2a2 (100% increase), whereas the metallothionein-1 gene, Mt1, was among the most downregulated genes (70% decrease). Several genes involved in lipid and cholesterol metabolism, including Scd1, Acly, Gpam, Elov16, Acsl5, Mvd, Insig1, and Apoa4, were found to be upregulated (≥30% increase) in Nas1−/− mice. In addition, Nas1−/− mice exhibited increased levels of hepatic lipid (≈16% increase), serum cholesterol (≈20% increase), and low-density lipoprotein (≈100% increase) and reduced hepatic glycogen (≈50% decrease) levels. In conclusion, these data suggest an altered lipid and cholesterol metabolism in the hyposulfatemic Nas1−/− mouse and provide new insights into the metabolic state of the liver in Nas1−/− mice.

scholarly journals Spectroscopic Evaluation of Red Blood Cells of Thalassemia Patients with Confocal Microscopy: A Pilot Study

Sensors ◽  
2020 ◽  
Vol 20 (14) ◽  
pp. 4039
Author(s):  
Laura Rey-Barroso ◽  
Mónica Roldán ◽  
Francisco J. Burgos-Fernández ◽  
Susanna Gassiot ◽  
Anna Ruiz Llobet ◽  
...  
Keyword(s):  
Iron Deficiency ◽  
Confocal Microscopy ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Pediatric Patients ◽  
Single Gene ◽  
Public Health Problem ◽  
Major Public Health Problem ◽  
Globin Genes ◽  
Molecular Tests

Hemoglobinopathies represent the most common single-gene defects in the world and pose a major public health problem, particularly in tropical countries, where they occur with high frequency. Diagnosing hemoglobinopathies can sometimes be difficult due to the coexistence of different causes of anemia, such as thalassemia and iron deficiency, and blood transfusions, among other factors, and requires expensive and complex molecular tests. This work explores the possibility of using spectral confocal microscopy as a diagnostic tool for thalassemia in pediatric patients, a disease caused by mutations in the globin genes that result in changes of the globin chains that form hemoglobin—in pediatric patients. Red blood cells (RBCs) from patients with different syndromes of alpha-thalassemia and iron deficiency (including anemia) as well as healthy (control) subjects were analyzed under a Leica TCS SP8 confocal microscope following different image acquisition protocols. We found that diseased RBCs exhibited autofluorescence when excited at 405 nm and their emission was collected in the spectral range from 425 nm to 790 nm. Three experimental descriptors calculated from the mean emission intensities at 502 nm, 579 nm, 628 nm, and 649 nm allowed us to discriminate between diseased and healthy cells. According to the results obtained, spectral confocal microscopy could serve as a tool in the diagnosis of thalassemia.

scholarly journals The effect of blood cells retained in rat livers during static cold storage on viability outcomes during normothermic machine perfusion

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Omar Haque ◽  
Casie A. Pendexter ◽  
Benjamin T. Wilks ◽  
Ehab O. A. Hafiz ◽  
James F. Markmann ◽  
...  
Keyword(s):  
Cold Storage ◽  
Blood Cells ◽  
Energy Charge ◽  
Ischemic Injury ◽  
Machine Perfusion ◽  
University Of Wisconsin ◽  
Normothermic Machine Perfusion ◽  
Preservation Solutions ◽  
Positive Correlations ◽  
Rat Livers

AbstractIn transplantation, livers are transported to recipients using static cold storage (SCS), whereby livers are exposed to cold ischemic injury that contribute to post-transplant risk factors. We hypothesized that flushing organs during procurement with cold preservation solutions could influence the number of donor blood cells retained in the allograft thereby exacerbating cold ischemic injury. We present the results of rat livers that underwent 24 h SCS after being flushed with a cold University of Wisconsin (UW) solution versus room temperature (RT) lactated ringers (LR) solution. These results were compared to livers that were not flushed prior to SCS and thoroughly flushed livers without SCS. We used viability and injury metrics collected during normothermic machine perfusion (NMP) and the number of retained peripheral cells (RPCs) measured by histology to compare outcomes. Compared to the cold UW flush group, livers flushed with RT LR had lower resistance, lactate, AST, and ALT at 6 h of NMP. The number of RPCs also had significant positive correlations with resistance, lactate, and potassium levels and a negative correlation with energy charge. In conclusion, livers exposed to cold UW flush prior to SCS appear to perform worse during NMP, compared to RT LR flush.

scholarly journals Impact of Red Blood Cells on Function and Metabolism of Porcine Deceased Donor Kidneys During Normothermic Machine Perfusion

2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Leonie H. Venema ◽  
L. Leonie van Leeuwen ◽  
Rene A. Posma ◽  
Harry van Goor ◽  
Rutger J. Ploeg ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Deceased Donor ◽  
Machine Perfusion ◽  
Normothermic Machine Perfusion
Sign in / Sign up

Export Citation Format

Share Document