BACKGROUND: The aim of our study was to assess the impact of different thawing protocols on morphological changes arising in cryopreserved human saphenous vein grafts. METHODS: The study was performed in 12 saphenous vein grafts harvested in brain death donors. Storage in the vapor phase of liquid nitrogen for 3 or 5 years followed. Two thawing protocols were tested: slow thawing in a refrigerator at temperature +4°C for 2 hr and rapid thawing-in a water bath at +37°C. Grafts were processed for scanning electron microscopy. Comparisons of continuous parameters under study between experimental groups were performed using the t-test (age, cold ischemia time, exposure to cryoprotectant, time of storage, total thawing time, mean thawing rate, morphology scoring of thawed HSVG) and the median test (HSVG length). Categorical parameters (sex and blood group) were formally tested using the chi-square test. RESULTS: All samples were evaluated according to morphological changes and scored in terms of morphologically intact endothelium, confluent endothelium with structural inhomogeneity, disruption of the intercellular contacts, separation of the endothelial cells, complete loss of the endothelium, and damage of the subendothelial layers. There is no statistically significant difference between the sample sets at the significance level of 0.05. There was no association with donors' age, sex, and time of storage. CONCLUSIONS: Human cryopreserved saphenous vein grafts in our experimental work showed no difference in terms of structural deterioration of the endothelial surface and basal membrane depending on different thawing protocols used.

• MeSH
• Time Factors MeSH
• Adult MeSH
• Endothelial Cells drug effects   transplantation   ultrastructure   MeSH
• Cryopreservation * MeSH
• Cryoprotective Agents pharmacology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Tissue and Organ Harvesting MeSH
• Tissue Survival MeSH
• Saphenous Vein drug effects   transplantation   ultrastructure   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH

Biophysical properties and microstructural changes of swelling cornea which caused by endothelial cells damage will be evaluated. Swelling cornea models were established by endothelial cells damage in 114 Sprague Dawley rats. Relative gray value, swelling rate and light transmittance were measured to evaluated the biophysical properties and microstructure changes were observed by transmission electron microscopy. Relative gray value decreased while swelling rate rose along with time and both of them reached relative stability after 7 days. Light transmittance showed a decline trend with time even after corneal thickness had reached stable stage. Observed by transmission electron microscopy, interfibrillar distance increased, fewer proteoglycans coating appeared and remnants proteoglycan branches became thinner and longer in 7 days. Diameter of fibrils didn't change obviously with time. In cornea edema models caused by endothelial cells damage, the changes of biophysical property and microstructure can help us evaluate corneal edema accurately and objectively.

• MeSH
• Endothelial Cells ultrastructure   MeSH
• Photography MeSH
• Disease Models, Animal MeSH
• Rats, Sprague-Dawley MeSH
• Endothelium, Corneal diagnostic imaging   ultrastructure   MeSH
• Corneal Stroma MeSH
• Microscopy, Electron, Transmission MeSH
• Corneal Endothelial Cell Loss diagnostic imaging   pathology   MeSH
• Ultrasonography MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH

BACKGROUND: Endothelial progenitor cells (EPCs) were indicated in vascular repair, angiogenesis of ischemic organs, and inhibition of formation of initial hyperplasia. Differentiation of endothelial cells (ECs) from human induced pluripotent stem cells (hiPSC)-derived endothelial cells (hiPSC-ECs) provides an unlimited supply for clinical application. Furthermore, magnetic cell labelling offers an effective way of targeting and visualization of hiPSC-ECs and is the next step towards in vivo studies. METHODS: ECs were differentiated from hiPSCs and labelled with uncoated superparamagnetic iron-oxide nanoparticles (uSPIONs). uSPION uptake was compared between hiPSC-ECs and mature ECs isolated from patients by software analysis of microscopy pictures after Prussian blue cell staining. The acute and long-term cytotoxic effects of uSPIONs were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay) and Annexin assay. RESULTS: We showed, for the first time, uptake of uncoated SPIONs (uSPIONs) by hiPSC-ECs. In comparison with mature ECs of identical genetic background hiPSC-ECs showed lower uSPION uptake. However, all the studied endothelial cells were effectively labelled and showed magnetic properties even with low labelling concentration of uSPIONs. uSPIONs prepared by microwave plasma synthesis did not show any cytotoxicity nor impair endothelial properties. CONCLUSION: We show that hiPSC-ECs labelling with low concentration of uSPIONs is feasible and does not show any toxic effects in vitro, which is an important step towards animal studies.

• MeSH
• Biomarkers MeSH
• Cell Differentiation * MeSH
• Human Umbilical Vein Endothelial Cells MeSH
• Endothelial Cells cytology   metabolism   ultrastructure   MeSH
• Immunohistochemistry MeSH
• Induced Pluripotent Stem Cells cytology   metabolism   ultrastructure   MeSH
• Cells, Cultured MeSH
• Humans MeSH
• Magnetite Nanoparticles * chemistry   MeSH
• Cell Survival MeSH
• Ferric Compounds * chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

Incomplete endothelialization of intracoronary stents has been associated with stent thrombosis and recurrent symptoms, whereas prolonged use of dual antiplatelet therapy increases bleeding-related adverse events. Facilitated endothelialization has the potential to improve clinical outcomes in patients who are unable to tolerate dual antiplatelet therapy. The objective of this study was to demonstrate the feasibility of magnetic cell capture to rapidly endothelialize intracoronary stents in a large animal model. A novel stent was developed from a magnetizable duplex stainless steel (2205 SS). Polylactic-co-glycolic acid and magnetite (Fe3O4) were used to synthesize biodegradable superparamagnetic iron oxide nanoparticles, and these were used to label autologous blood outgrowth endothelial cells. Magnetic 2205 SS and nonmagnetic 316L SS control stents were implanted in the coronary arteries of pigs (n = 11), followed by intracoronary delivery of magnetically labeled cells to 2205 SS stents. In this study, we show extensive endothelialization of magnetic 2205 SS stents (median 98.4% cell coverage) within 3 days, whereas the control 316L SS stents exhibited significantly less coverage (median 48.9% cell coverage, p < 0.0001). This demonstrates the ability of intracoronary delivery of magnetic nanoparticle labeled autologous endothelial cells to improve endothelialization of magnetized coronary stents within 3 days of implantation.

• MeSH
• Endothelial Cells cytology   drug effects   ultrastructure   MeSH
• Phenotype MeSH
• Metals chemistry   MeSH
• Nanoparticles chemistry   ultrastructure   MeSH
• Stainless Steel pharmacology   MeSH
• Swine MeSH
• Stents * MeSH
• Animals MeSH
• Check Tag
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH

Focal cerebral contusion can be dynamic and expansive. It has been proved that subsequent expansive contusion is caused by brain parenchyma damage, especially BBB damage. We investigated a group of patients with traumatic brain injury. The patients (n=18) were divided into group I (n=7) of patients submitted to neurosurgery due to expansive contusion, and group II (n=11) of patients without surgery. Serum concentrations of NSE and S-100B protein were measured by electrochemiluminescence immunoassay, interleukin-6 (IL-6) was measured by chemiluminescent sequential immunometric assay and matrix metalloproteinases (MMP-9, MMP-2) were measured by immunoassays. Cortical biopsy specimens of brain were investigated by electron microscopy in patients with trauma brain injury submitted to neurosurgery. Biochemical investigation from first day up to third day after traumatic brain injury proved increased values of IL-6 (302.2+/-119.9 vs. 59.6+/-11.9 ng/l, p<0.02) and S-100B protein (3.064+/-1.064 vs. 0.649+/-0.182 microg/l, p<0.05) in patients with expansive lesion compared to patients without expansive contusion. Significantly higher levels of MMP-9 (150.4+/-28.46 vs. 74.11+/-13.16 ng/l, p<0.05) and of MMP-2 (814.5+/-126.3 vs. 523.1+/-25.28 ng/l, p<0.05) were found during first 3 days after admission in group I compared to group II. MMP-9 has also elevated in group II from lower values after admission (74.11+/-13.16 ng/l) up to high levels on the 10th day of hospitalization (225.1+/-49.35 ng/l). Ultrastructural investigation of endothelial cells and surrounded tissue revealed perivascular hemorrhage, increased pinocytic activity of endothelial cells, and cytotoxic edema of astroglial cells. Multivesical bodies were disclosed inside the endothelial cells. Higher levels of serum protein S-100B and IL-6 correlated with ultrastructural changes of endothelial cells, and with inflammatory response following TBI, respectively.

• MeSH
• Astrocytes pathology   ultrastructure   MeSH
• Biomarkers blood   MeSH
• Biopsy MeSH
• Microscopy, Electron MeSH
• Encephalitis immunology   pathology   MeSH
• Endothelial Cells pathology   ultrastructure   MeSH
• Financing, Organized MeSH
• Blood-Brain Barrier immunology   metabolism   pathology   MeSH
• Interleukin-6 blood   MeSH
• Humans MeSH
• Nerve Growth Factors blood   MeSH
• Brain Injuries immunology   metabolism   pathology   MeSH
• S100 Proteins blood   MeSH
• Tight Junctions pathology   ultrastructure   MeSH
• Check Tag
• Humans MeSH

Higher harmonic contributions in the movement of an oscillating atomic force microscopy (AFM) cantilever are generated by nonlinear tip-sample interactions, yielding additional information on structure and physical properties such as sample stiffness. Higher harmonic amplitudes are strongly enhanced in liquid compared to the operation in air, and were previously reported to result in better structural resolution in highly organized lattices of proteins in bacterial S-layers and viral capsids [J. Preiner, J. Tang, V. Pastushenko, P. Hinterdorfer, Phys. Rev. Lett. 99 (2007) 046102]. We compared first and second harmonics AFM imaging of live and fixed human lung epithelial cells, and microvascular endothelial cells from mouse myocardium (MyEnd). Phase-distance cycles revealed that the second harmonic phase is 8 times more sensitive than the first harmonic phase with respect to variations in the distance between cantilever and sample surface. Frequency spectra were acquired at different positions on living and fixed cells with second harmonic amplitude values correlating with the sample stiffness. We conclude that variations in sample stiffness and corresponding changes in the cantilever-sample distance, latter effect caused by the finite feedback response, result in second harmonic images with improved contrast and information that is not attainable in the fundamental frequency of an oscillating cantilever.

• MeSH
• Endothelial Cells ultrastructure   MeSH
• Epithelial Cells MeSH
• Eukaryotic Cells MeSH
• Humans MeSH
• Microscopy, Atomic Force methods   MeSH
• Myocardium cytology   MeSH
• Mice MeSH
• Lung cytology   MeSH
• Elasticity MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH

Genetic predisposition and social stress may represent important risk factors in etiology of hypertension associated with endothelial dysfunction. Perturbations of endothelial structural integrity are also critical for the pathogenesis of vascular diseases. We examined effect of chronic social stress on structure of aortic endothelium in borderline hypertensive (BHR) and normotensive Wistar rats. Male BHR - offspring of Wistar mothers and SHR fathers and age-matched W were exposed to 6-week crowding stress (5 rats/cage, 200 cm2/rat). Aortic tissue was processed for electron microscopy and NO synthase activity measurement. Crowding stress significantly increased blood pressure in BHR compared to basal values (140+/-3 mm Hg vs. 130+/-3 mm Hg, p<0.05) and reduced enzyme activity by 37 % (p<0.01) in the aorta of BHR. Local slight structural alterations of endothelium were found in non-stressed BHR (p<0.001) when compared with Wistar rats. Chronic stress caused marked (p<0.005) subcellular injury of endothelial cells in aorta of BHR characterized by mitochondrial damage, presence of vacuoles, increased number of lysosomes, Weibel-Palade bodies, changes of intercellular connections and local disruption of endothelium, while only slight changes were seen in Wistar rats. Results suggest increased sensitivity of aortic endothelium of BHR to chronic crowding that may contribute to acceleration of arterial dysfunction.

• MeSH
• Aorta, Thoracic enzymology   ultrastructure   MeSH
• Behavior, Animal * MeSH
• Chronic Disease MeSH
• Endothelial Cells enzymology   ultrastructure   MeSH
• Hypertension genetics   metabolism   pathology   physiopathology   psychology   MeSH
• Blood Pressure MeSH
• Rats MeSH
• Disease Models, Animal MeSH
• Crowding * MeSH
• Rats, Inbred SHR MeSH
• Rats, Wistar MeSH
• Disease Progression MeSH
• Stress, Psychological metabolism   pathology   physiopathology   MeSH
• Nitric Oxide Synthase metabolism   MeSH
• Microscopy, Electron, Transmission MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

• MeSH
• Diabetes Mellitus chemically induced   pathology   MeSH
• Endothelial Cells enzymology   ultrastructure   MeSH
• Research Support as Topic MeSH
• Hypertension chemically induced   complications   pathology   MeSH
• Capillaries enzymology   ultrastructure   MeSH
• Diabetes Complications enzymology   pathology   MeSH
• Myocardium enzymology   ultrastructure   MeSH
• NG-Nitroarginine Methyl Ester MeSH
• Rats, Wistar MeSH
• Heart Failure etiology   chemically induced   pathology   MeSH
• Streptozocin MeSH
• Nitric Oxide Synthase antagonists & inhibitors   metabolism   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Animals MeSH
• Publication type
• Comparative Study MeSH