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Recently the matrix of umbilical cord began to use as an alternative source of stem cells additionally to the blood of umbilical cord. Umbilical cord has been used mainly for mesenchymal stem cell banking. The immunological characteristics of mesenchymal stem cells in combination with their ability to avoid rejection make them an attractive biological material for transplantations. In this study the isolation of small in size pluripotent stem cells from umbilical cord expressing early transcription factors with characteristics that resemble to embryonic stem cells is investigated. Pluripotent stem cells were isolated from human umbilical cords, by a new strategy method based on unique characteristics such as the small size and the positivity on early transcription factors OCT and Nanog. An enriched population of CXCR4(+) OCT(+) Nanog(+) CD45(-) small stem cells from the cord was isolated. This fraction was able to create alkaline phosphatase positive like spheres forms in a mesenchymal layer with multilineage differentiation capacity. Our results were assessed by RT PCR and electophoresis for the pluripotent genes. These data suggest that umbilical cord provides an attractive source not only of mesenchymal stem cells but moreover of pluripotent stem cells. The method described herein should be applied in the field of stem cell banking in addition to the classical umbilical cord harvesting method. Isolation of a population of cells with pluripotent characteristics from umbilical cord. Adoption of a second centrifugation step for the pluripotent stem isolation. Increasing the value of the cord and explaining the pluripotency. This work will enhance the value of umbilical cord harvesting.

Background: Chronic obstructive pulmonary disease presents with two different phenotypes: chronic bronchitis and emphysema with parenchymal destruction. Decreased expression of vascular endothelial growth factor and increased endothelial cell apoptosis are considered major factors for emphysema. Stem cells have the ability of vascular regeneration and function as a repair mechanism for the damaged endothelial cells. Currently, minimally invasive interventional procedures such as placement of valves, bio-foam or coils are performed in order to improve the disturbed mechanical function in emphysema patients. However, these procedures cannot restore functional lung tissue. Additionally stem cell instillation into the parenchyma has been used in clinical studies aiming to improve overall respiratory function and quality of life., Methods: In our current experiment we induced emphysema with a DDMC non-viral vector in BALBC mice and simultaneously instilled stem cells testing the hyposthesis that they might have a protective role against the development of emphysema. The mice were divided into four groups: a) control, b) 50.000 cells, c) 75.000 and d) 100.000 cells., Results: Lung pathological findings revealed that all treatment groups had less damage compared to the control group. Additionally, we observed that emphysema lesions were less around vessels in an area of 10 μm., Conclusions: Our findings indicate that stem cell instillation can have a regenerative role if applied upon a tissue scaffold with vessel around., Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_195.

Purpose: The aim of the study was to investigate the effect of angiogenesis inhibition by bevacizumab, a monoclonal anti-vascular endothelial growth factor (VEGF) antibody, on the healing process of colonic anastomoses in rats, assessing some specific involved factors. This new agent is used mainly in metastatic colorectal cancer. The angiogenesis plays an important role in both wound healing and metastatic invasion and spread of malignant cells. There has not been any evidence assessing the optimal time for its safe use in operated patients., Materials and Methods: Forty Wistar rats were randomly allocated into four equal groups. A colonic anastomosis was performed in all rats. Half of them received intraoperatively a single dose of bevacizumab 5 mg/body weight and the rest received placebo. The animals were sacrificed on the 7th (Avastin 7th, placebo 7th) and 14th (Avastin 14th, placebo 14th) postoperative day. The anastomosis was resected and sent for histological study and for tissue biochemical assays (VEGF, endothelin-1 (ET-1), C-reactive protein (CRP), pro-oxidant-antioxidant balance (PAB), carbonylated proteins, hydroxyproline) using specific enzyme-linked immunosorbent assay kits. For statistical analysis, the Mann-Whitney U test was used (of statistical significance when P < 0.05)., Results: No complication or anastomotic dehiscence was observed. Histology did not reveal statistically significant differences between groups concerning degree of inflammation, fibroblasts, collagen, and fibrosis. Likewise, hydroxyproline levels did not differ. However, some statistically significant differences were found in VEGF, CRP and carbonyl proteins (Avastin 7th vs placebo 7th, placebo 14th vs placebo 7th), ET-1, and PAB (Avastin 14th vs Avastin 7th), which did not finally affect the collagen synthesis marker hydroxyproline, nor did the anastomotic strength., Conclusions: Bevacizumab, when administered intraoperatively, has no significant effect on colon anastomotic healing in rats despite a transient mild ischemia.

Soon after the diagnosis of pellagra in a 20-year-old patient with beta thalassemia, bilateral intumescent cataracts rapidly developed. We believe the patient's crystalline lenses were at an increased oxidative state due to iron overload from the thalassemia. Depletion of the lens epithelial cells of an important antioxidative agent (glutathione) as a result of niacin (vitamin B3) deficiency due to pellagra reduced the antioxidative capacity of the lenses. The oxidative damage led to rapid development of cataracts.

Aim: A small number of left internal thoracic artery (LITA) grafts are occluded at 3 years after the operation or show more than 50% stenosis of the lumen. The purpose of this study is to examine factors related to the morphology of the wall and to the function of the cell population of LITA grafts before implantation, in order to evaluate their quality and the viability, in a follow-up examination., Methods: Fifteen LITA grafts were examined with light microscopy, for their morphology, endothelial cell coverage, apoptosis and cell proliferation, scanning electron microscopy and transmission electron microscopy., Results: Increase of the thickness of the intima (14.21+/-1.28 mm), mean thickness of media 160.37+/-11.97 mm, detachment of intima from media, presence of foam cells in the media, low endothelial coverage (40.638+/-16.864), increase of apoptosis in intima (46.38+/-13.46), sub-intima (29.3+/-8.54), media (34.91+/-6.05) and adventitia (40.21+/-5.36), blood cells penetration of the intima through disruptions between endothelial cells are findings of LITA grafts before implantation. Cell proliferation was not detected in the wall of any graft. Follow-up examination 6 months and 2.5 years after the operation showed normal function of LITA grafts., Conclusions: Besides of the wall injury and the initiated atherosclerotic lesions, LITA grafts are well functioning at the time of the follow-up examination. Maybe our findings are related to the later occlusion of the referred in the literature small number of LITA grafts.

Background: Twenty percent of the long saphenous vein (LSV) grafts that are employed as coronary bypass conduits occlude during the first year after the operation. The aim of this study was to evaluate the morphological parameters of the LSV grafts before implantation as predictors for the early occlusion of the grafts., Methods: Forty-two samples of LSV grafts were examined via light, transmission electron, and scanning electron microscopy and evaluated clinically and by angiography at 6 months and 2 years after the operation. Morphological parameters were statistically analyzed and examined for their significance on the viability of the vein grafts., Results: Six (14.28%) of the examined grafts occluded within the first 6 months after the operation, and 11 grafts (26.19%) occluded within the first 2 years. The grafts that occluded at 6 months were characterized by thick intima (mean value, 206+/-32.29 vs. 67.44+/-10.17 in the group functioning normally and 98.42+/-34 in the group occluded within 2 years), low endothelial coverage (22.7+/-4.04 vs. 64.61+/-2.89 and 26.06+/-1.78 in the corresponding groups), and narrow lumen (46.73+/-9.69 vs. 527.18+/-45.78 and 204.26+/-16.5 in the corresponding groups). The presence of foam cells, edema, calcification, neovascularization, and thrombus in the lumen of the veins is frequently observed in the wall of the occluded vein grafts, whereas fibrosis does not seem to be related., Conclusions: LSV grafts with low endothelial cell coverage, stenosis of the lumen, and thick walls are at an increased risk of developing intrawall lesions that lead to early graft failure.

Monocytes encounter basement membranes and interact with laminins while crossing the vascular barrier. It is known that these cells possess ecto-protein kinase activity on their surface. Several proteins of the extracellular matrix can be phosphorylated by ectokinases. Therefore, it has been hypothesized that monocyte ectokinases could phosphorylate laminins and influence their biological properties. In order to test the above hypothesis, we used intact human monocytes and adenosine triphosphate labeled with radioactive phosphate at the third phosphate ([gamma-32P]-ATP) to phosphorylate laminin-1. Autoradiography after sodium dodecyl sulphate polyacrylamyde gel electrophoresis (SDS-PAGE) electrophoresis indicated phosphorylation of laminin-1 on the beta and/or gamma chains. After phosphorylation, phosphoserine could be detected on Western blots by a specific monoclonal antibody. Phosphorylation was not detected when monocytes were pre-treated with trypsin and was inhibited by a specific ecto-protein kinase inhibitor (K252b). Laminin phosphorylation was also inhibited by heparin, a known inhibitor of casein kinase II and by pretreatment of monocytes by a monoclonal anti-casein kinase II antibody. Heparin binding, cell attachment and proliferation, and monocyte migration were enhanced on the phosphorylated laminin-1 as compared to the non-phosphorylated controls. These data indicate that laminin-1 can be phosphorylated by monocyte casein kinase II type ectokinase. This phosphorylation influences important functions of laminin and therefore could provide an additional means for the interaction of monocytes with basement membranes.

Unlabelled: The synthetic laminin pentapeptide tyrosyl-isoleucyl-glycyl-seryl-arginine (YIGSR) binds to a metastasis associated high-affinity laminin receptor. The aim of this study was to investigate if the radiolabeled peptide can be considered as a basis for a potential tumor-imaging radiopharmaceutical., Methods: Iodine-131-labeled YIGSR was injected in mice inoculated with Lewis Lung carcinoma, as well as in normal controls. The experimental animals were imaged on a gamma camera 10 hr after peptide administration. The same peptide was also labeled with 125I and administered to tumor-bearing and normal mice. At various time-points after peptide administration, the experimental animals were killed, and the radioactivity in the tumor, lung, liver and spleen was measured. Microscopic autoradiography was performed in histological sections of the same tissues., Results: The tumor and the spleen of tumor-bearing animals were imaged on a gamma camera. No significant blood-pool background was detected. No other organ except urinary bladder and thyroid was imaged in normal animals. The peptide was retained on tumor and spleen of tumor-bearing animals. Twenty-four hours after peptide administration, the tumor, lung, liver and spleen of animals with tumors contained significantly more radioactivity than the same tissues of equally treated normal controls. The radiolabeled peptide YIGSR was detected by microscopic autoradiography on the surface of certain tumor cells, but not on the surface of any normal cell., Conclusion: Although extensive research is still required, the peptide YIGSR can be considered as a basis for the development of a receptor specific radiopharmaceutical useful for the in vivo estimation of the metastatic potential of tumors. This radiopharmaceutical may be helpful in staging and prognostic-related decisions on cancer treatment.

Three distinctive heparin-binding sites were observed in type IV collagen by the use of rotary shadowing: in the NC1 domain and at distances 100 and 300 nm from the NC1 domain. Scatchard analysis indicated different affinities for these sites. Electron microscopic analysis of heparin-type IV collagen interaction with increasing salt concentrations showed the different affinities to be NC1 greater than 100 nm greater than 300 nm. The NC1 domain bound specifically to chondroitin/dermatan sulfate side chains as well. This binding was observed at the electron microscope and in solid-phase binding assays (where chondroitin sulfate could compete for the binding of [3H]heparin to NC1-coated substrata). The triple helix-rich, rod-like domain of type IV collagen did not bind to chondroitin/dermatan sulfate side chains. In solid-phase binding assays only heparin could compete for the binding of [3H]heparin to this domain. In order to more precisely map potential heparin-binding sites in type IV collagen, we chemically synthesized 17 arginine- and lysine-containing peptides from the alpha 1(IV) and alpha 2(IV) chains. Three peptides from the known sequence of the alpha 1(IV) and alpha 2(IV) chains were shown to specifically bind heparin: peptide Hep-I (TAGSCLRKFSTM), from the alpha 1(NC1) chain, peptide Hep-II (LAGSCLARFSTM), a peptide corresponding to the same sequence in peptide Hep-I from the alpha 2 (NC1) chain, and peptide Hep-III (GEFYFDLRLKGDK) which contained an interruption of the triple helical sequence of the alpha 1(IV) chain at about 300 nm from the NC1 domain, were demonstrated to bind heparin in solid-phase binding assays and compete for the binding of [3H]heparin to type IV collagen-coated substrata. Therefore, each of these peptides may represent a potential heparin-binding site in type IV collagen. The mapping of the binding of heparin or related structures, such as heparan sulfate proteoglycan, to specific sequences of type IV collagen could help the understanding of several structural and functional properties of this basement membrane protein as well as interactions with other basement membrane and/or cell surface-associated macromolecules.

A new deficient glucose 6-phosphate dehydrogenase (G6PD) variant, G6PD Thessaloniki, which was found in the red blood cells of a 70-year-old woman who had idiopathic myelofibrosis, is described. G6PD Thessaloniki had a low Michaelis constant (Km) for G6P (20 microM), high Km for NADP (10.1 microM), normal pH optimum, reduced heat stability, decreased electrophoretic mobility (96-98% of the normal), increased 2-deoxy-G6P and decreased galactose 6-phosphate utilization. Several other enzymatic activities measured in the patient's red blood cells were normal. Studies of red blood cell survival and glucose utilization gave evidence of haemolysis caused by defective glucose utilization by the pentose phosphate pathway. The only son of the patient had normal G6PD in his red blood cells. In an attempt to investigate the origin of G6PD Thessaloniki, heat stability tests of G6PD extracted from the patient's skin have been performed.