Journal articles: 'In-Capillary labeling'

1

Theilen, Hermann, and Wolfgang Kuschinsky. "Fluorescence Labeling of the Capillary Network in Rat Brains." Journal of Cerebral Blood Flow & Metabolism 12, no. 2 (March 1992): 347–50. http://dx.doi.org/10.1038/jcbfm.1992.47.

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To assess the reliability of fluorescence methods for a quantitative staining of brain capillaries, three different immunohistochemical fluorescent markers were used in the rat brain. Staining of the basement membrane by antibodies directed against fibronectin was compared, in the same brain section, with simultaneous staining of the vascular endothelium constituents nonmuscle myosin or von Willebrand factor (factor VIII). These stainings all resulted in identical patterns, which demonstrates their suitability for capillary staining in the brain. It has been claimed that fixation of the tissue results in the appearance of spurious capillary spots. Such a fixation artifact could be excluded using nonmuscle myosin staining. These results validate the methods of quantitative fluorescent microscopical staining of capillary morphology in the brain and therefore support our concept of a continuous perfusion of all capillaries in the brains of conscious rats.

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Skowronski, Mariusz T., Janne Lebeck, Aleksandra Rojek, Jeppe Praetorius, Ernst-Martin Füchtbauer, Jørgen Frøkiær, and Søren Nielsen. "AQP7 is localized in capillaries of adipose tissue, cardiac and striated muscle: implications in glycerol metabolism." American Journal of Physiology-Renal Physiology 292, no. 3 (March 2007): F956—F965. http://dx.doi.org/10.1152/ajprenal.00314.2006.

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Aquaporin (AQP7) is expressed in proximal tubules and is involved in glycerol uptake. The cellular expression and physiological function in other organs remain largely undefined. AQP7 knockout (KO) mice were generated and used for immunohistochemical analyses to define the organ and cellular expression of AQP7. AQP7 labeling was found in kidney proximal tubule, heart, skeletal muscle, testis, epididymis, as well as in white and brown adipose tissue (WAT and BAT) of wild-type mice. Importantly, immunoreactivity was completely absent from these tissues in AQP7 KO mice. At the cellular level, the capillary endothelium WAT and BAT displayed prominent staining, whereas AQP7 labeling in adipocyte membranes was undetectable. Double-labeling confocal microscopy revealed coexpression of AQP7 with capillary AQP1 but not with adipocyte GLUT4. Moreover, immunoelectron microscopy and RT-PCR of isolated microvessels confirmed the vascular AQP7 expression. Distinct immunolabeling of the capillary endothelium was also observed in both skeletal and heart muscle with no apparent staining of skeletal or cardiac myocytes. As previously reported, specific immunolabeling was confined to brush border in segment 3 renal proximal tubules and to spermatids and spermatozoa in male reproductive tract. The expression of AQP7 was induced up to 2.2-fold in WAT of mice with streptozotocin-induced diabetes mellitus (S-DM) compared with controls and fasting for 72 h (but not 24 h) induced significant increase in AQP7 expression. In conclusion, AQP7 is expressed in capillary endothelia of adipose tissue (and cardiac and striated muscle) and is upregulated in WAT in response to S-DM supporting its role in glycerol metabolism.

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Akita, Masumi, Kayoko Tanaka, Sachiko Matsumoto, Kumiko Komatsu, and Keiko Fujita. "Detection of the Hematopoietic Stem and Progenitor Cell Marker CD133 during Angiogenesis in Three-Dimensional Collagen Gel Culture." Stem Cells International 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/927403.

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We detected the hematopoietic stem and progenitor cell marker CD133 using immunogold labeling during angiogenesis in a three-dimensional collagen gel culture. CD133-positive cells were present in capillary tubes newly formed from aortic explants in vitro. The CD133-positive cell population had the capacity to form capillary tubes. Lovastatin strongly inhibited cell migration from aortic explants and caused the degradation of the capillary tubes. The present study provides insight into the function of CD133 during angiogenesis as well as an explanation for the antiangiogenic effect of statins.

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Kuo, Chien-Yuan, Shwu-Huey Wang, Chunchi Lin, Sylvain Kuo-Shiang Liao, Wei-Ting Hung, Jim-Min Fang, and Wen-Bin Yang. "Application of 2,3-Naphthalenediamine in Labeling Natural Carbohydrates for Capillary Electrophoresis." Molecules 17, no. 6 (June 15, 2012): 7387–400. http://dx.doi.org/10.3390/molecules17067387.

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Vetterlein, F., A. Petho, and G. Schmidt. "Distribution of capillary blood flow in rat kidney during postischemic renal failure." American Journal of Physiology-Heart and Circulatory Physiology 251, no. 3 (September 1, 1986): H510—H519. http://dx.doi.org/10.1152/ajpheart.1986.251.3.h510.

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Changes in distribution of intrarenal blood flow were studied in anesthetized rats during the acute phase of postischemic renal failure (1 h renal artery occlusion, 1 h reflow). Distribution of capillary plasma flow was determined by injecting fluorescein-isothiocyanate-globulin and lissamine-rhodamine-B200-globulin 1, 3, or 10 min prior to rapid freezing of the kidney. In histological sections it was possible to differentiate among the vessels perfused during the time of labeling because of their respective fluorescence. In these experiments all glomeruli became labeled within 1 min, although in contrast to the controls, the glomerular capillary network itself was not filled completely in the postocclusion organs. Incomplete labeling was far more pronounced, however, in the postglomerular network of the occlusion experiments. Due to this effect in the cortex and in the medulla, 11 and 58% of tissue, respectively, were found lying at a distance of more than 60 microns from the next vessel labeled after 1 min of dye circulation. In the control experiments there was no tissue within this distance. Prolonging the time of labeling up to 10 min caused little change in this pattern of distribution. In the occlusion experiments, the globulins were observed in nearly all Bowman spaces, but in less than half of the tubular lumina. The results strengthen the view that the ischemic insult leads primarily to disturbance of the postglomerular perfusion, which then results in trophic damage of the tubular system mainly within the renal medulla.

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Vetterlein, F., B. Demmerle, A. Bardosi, U. Gobel, and G. Schmidt. "Determination of capillary perfusion pattern in rat brain by timed plasma labeling." American Journal of Physiology-Heart and Circulatory Physiology 258, no. 1 (January 1, 1990): H80—H84. http://dx.doi.org/10.1152/ajpheart.1990.258.1.h80.

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The pattern of capillary perfusion was studied in the brain of anesthetized rats. Two plasma labels were used to demonstrate the density of capillaries perfused during a 10-min period [fluorescein isothiocyanate (FITC) globulin], as well as during a 10-, 3-, or 1-s period [lissamine-rhodamine B 200 (RB200) globulin, infused into the left heart chamber], respectively. A special biopsy cutting-freezing system was used to withdraw brain tissue via a cranial window for histological analysis of dye distribution at the end of the infusion period. Complete labeling of all capillaries was already found after 10 s of dye circulation. However, intra-arterial dye infusion for 3 and 1 s led to reduced filling of capillaries: cortex 86.6 +/- 5.2 and 6.8 +/- 1.8%, hippocampus 95.0 +/- 1.6 and 9.9 +/- 2.1%, and thalamus 97.9 +/- 1.0 and 11.7 +/- 1.8%, respectively. The period of 1 s was found to be the circulation time from left heart chamber to brain capillaries. It can thus be concluded that in the studied brain areas greater than 85% of capillaries are reached by a plasma flow within 2 s and that the remaining small fraction completely fills within 10 s.

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7

Colyer, Christa. "Noncovalent Labeling of Proteins in Capillary Electrophoresis with Laser-Induced Fluorescence Detection." Cell Biochemistry and Biophysics 33, no. 3 (2000): 323–37. http://dx.doi.org/10.1385/cbb:33:3:323.

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Fujimoto, T., and S. J. Singer. "Immunocytochemical studies of endothelial cells in vivo. II. Chicken aortic and capillary endothelial cells exhibit different cell surface distributions of the integrin complex." Journal of Histochemistry & Cytochemistry 36, no. 10 (October 1988): 1309–17. http://dx.doi.org/10.1177/36.10.2458407.

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Frozen sections of chicken tissues containing aortic and capillary endothelial cells were immunolabeled with two mouse monoclonal antibodies directed to different epitopes of the chicken integrin beta-chain. Integrin is an integral membrane protein complex that is believed to mediate a transmembrane linkage between the extracellular matrix and the actin cytoskeleton. In immunofluorescence experiments with semi-thin frozen sections, the aortic endothelial cells were labeled for integrin all around their surfaces, whereas capillary endothelial cells of heart and kidney were labeled only on their basal surfaces. At the immunofluorescence level of resolution, the distribution of integrin appeared to be correlated with that of F-actin in double-labeling experiments with NBD-phallacidin. These different distributions of integrin on the two types of endothelial cells were definitively confirmed by immunoelectron microscopic labeling with the monoclonal antibodies on ultra-thin frozen sections. These results therefore indicate that the luminal surfaces, as well as the underlying cytoskeleton of capillary endothelial cells, are significantly different in structure from those of aortic endothelial cells. These differences may reflect the vastly different hemodynamic stress to which the two types of endothelial cells are subjected, and in addition may mediate different adhesion properties of the luminal surfaces of the two cell types.

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Gosk, Sara, Charlotte Vermehren, Gert Storm, and Torben Moos. "Targeting Anti—Transferrin Receptor Antibody (OX26) and OX26-Conjugated Liposomes to Brain Capillary Endothelial Cells Using In Situ Perfusion." Journal of Cerebral Blood Flow & Metabolism 24, no. 11 (November 2004): 1193–204. http://dx.doi.org/10.1097/01.wcb.0000135592.28823.47.

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Brain capillary endothelial cells (BCECs) express transferrin receptors. The uptake of a potential drug vector (OX26, or anti—transferrin receptor antibody IgG2a) conjugated to polyethyleneglycol-coated liposomes by BCECs was studied using in situ perfusion in 18-day-old rats in which the uptake of OX26 is almost twice as high as in the adult rat. Using radio-labeling, the uptake of OX26 by BCECs after 15-minute perfusion was approximately 16 times higher than that of nonimmune IgG2a (Ni-IgG2a). OX26 and OX26-conjugated liposomes selectively distributed to BCECs, leaving choroid plexus epithelium, neurons, and glia unlabeled. Ni-IgG2a and unconjugated liposomes did not reveal any labeling of BCECs. The labeling of BCECs by OX26 was profoundly higher than that of transferrin. Perfusion with albumin for 15 minutes did not reveal any labeling of neurons or glia, thus confirming the integrity of the blood—brain barrier. The failure to label neurons and glia shows that OX26 and OX26-conjugated liposomes did not pass through BCECs. The expression of transferrin receptors by endothelial cells selective to the brain qualifies OX26 as a candidate for blood-to-endothelium transport. A specifically designed formulation of liposomes may allow for their degradation within BCECs, leading to subsequent transport of liposomal cargo further into the brain.

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10

Latorre, Rosa M., Santiago Hernández-Cassou, and Javier Saurina. "Strategies for in-capillary derivatization of amino acids in capillary electrophoresis using 1,2-naphthoquinone-4-sulfonate as a labeling reagent." Journal of Chromatography A 934, no. 1-2 (November 2001): 105–12. http://dx.doi.org/10.1016/s0021-9673(01)01293-6.

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11

Aktas, Ranan Gullhan, and Robert J. Kayton. "Electron Microscopic Immunolocalization of Basic Fibroblast Growth Factor-Like Molecules in Capillary Endothelial Cells." Microscopy and Microanalysis 4, S2 (July 1998): 1100–1101. http://dx.doi.org/10.1017/s1431927600025629.

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Basic fibroblast growth factor (bFGF) is a potent angiogenic polypeptide. It promotes angiogenesis in vivo and in vitro by stimulating migration, proliferation and proteolytic activity of endothelial cells. Whereas several effects of exogenous bFGF on endothelial cells have been described, it has remained unclear how endogenous bFGF produced by vascular endothelial cells regulate angiogenesis.To further investigate functional implications of the distribution of bFGF, we undertook the present study. Our aims were (i) to identify the specific location of bFGF in endothelial cells using electron microscopy immunogold labeling technique (ii) to determine the distribution of bFGF in capillaries of different types of tissues.Tissue samples from sciatic nerve, hippocampus, adrenal gland and kidney of normal adult rats were fixed in 4% paraformaldehyde/1 to 5% glutaraldehyde and embedded in Spurr's resin. Ultrathin sections were labeled with either polyclonal (F3393-Sigma) or monoclonal antibodies (F6162-Sigma, C3316-ZymoGenetics) specific for bFGF using a two-step immunogold labeling method.

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12

Vetterlein, F., M. Prange, D. Lubrich, J. Pedina, M. Neckel, and G. Schmidt. "Capillary perfusion pattern and microvascular geometry in heterogeneous hypoxic areas of hypoperfused rat myocardium." American Journal of Physiology-Heart and Circulatory Physiology 268, no. 6 (June 1, 1995): H2183—H2194. http://dx.doi.org/10.1152/ajpheart.1995.268.6.h2183.

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The origin of heterogeneities in tissue oxygenation due to low-flow ischemia was studied in hypoperfused myocardium of anesthetized rats. In frozen sections of myocardial biopsies the localization of increases in NADH fluorescence, an indicator of tissue hypoxia, was compared with microvascular flow distribution and capillary geometry. The latter parameters were accomplished through capillary labeling with indicator dyes in vivo and enzyme-histochemical staining in vitro, respectively. Most NADH-fluorescent areas were found to have developed despite sustained capillary flow. When the fractions of arterial, venous, and intermediate capillary segments were analyzed within circumscribed hypoxic fields (< 200 microns diam), frequencies of 30.7 +/- 6.1, 35.3 +/- 5.3, and 30.8 +/- 5.0%, respectively, were found. In contrast, a significantly higher fraction of arterial segments (63.2 +/- 3.3%) and a lower percentage of venous segments (16.4 +/- 2.5%) were determined in nonhypoxic islands enclosed by hypoxic tissue. These results support the view that the latter zones are located near the arterial portion of the capillary bed where their oxygenation is favored during low-flow states. This effect appears to contribute to the supply heterogeneities in hypoperfused myocardium.

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13

Vetterlein, F., U. Keitel, and G. Schmidt. "Capillary filling kinetics in the rabbit heart during normoxemia and hypoxemia." American Journal of Physiology-Heart and Circulatory Physiology 264, no. 2 (February 1, 1993): H287—H293. http://dx.doi.org/10.1152/ajpheart.1993.264.2.h287.

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In experiments on anesthetized rabbits the kinetics of capillary plasma filling in the heart during normoxemia and hypoxemia were studied. Three gamma globulins originating from three different species were infused into the left atrium for various periods of time. The hearts were shock frozen, and the respective globulins were immunohistochemically identified in parallel sections. The anatomic capillary density was determined by staining the capillary basement membrane. During normoxemia 69 and 66% (subepicardium and subendocardium, respectively) of the capillaries were labeled within 2 s, 84 and 78% within 5 s, and 96 and 92% within 10 s. Labeling was complete after 20 s. Hypoxemia (arterial PO2 27 mmHg, 5 min) led to a significant acceleration of capillary filling kinetics: 93 and 95% within 2 s, 98 and 99% within 5 s, 100 and 99% within 10 s. During hypoxemic conditions the entire left coronary flow was found increased by a factor of 2.3. The data may best be explained by the fact that hypoxemia does not lead to mobilization of previously nonperfused capillaries but induces either an amplification of capillary flow velocities or an increased frequency of periods with high capillary blood flow.

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14

Bayer, Ernst, Hartmut Frank, Jürgen Gerhardt, and Graeme Nicholson. "Capillary Gas Chromatographic Analysis of Amino Acids by Enantiomer Labeling." Journal of AOAC INTERNATIONAL 70, no. 2 (March 1, 1987): 234–40. http://dx.doi.org/10.1093/jaoac/70.2.234.

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Abstract The optical isomers of amino acids can be easily separated by gas chromatography using capillary columns coated with the chiral polysiloxane peptide, Chirasil-Val. Quantitative trace amino acid analysis in complex mixtures such as biological fluids, sea water, or protein hydrolysates can be achieved by enantiomer labeling: The D-amino acid enantiomers, which do not occur naturally, are added to the sample prior to analysis as internal standards. Because the D-enantiomers show the same physical and chemical properties as the natural L-enantiomers, they are ideal standard references. In routine analysis, the derivatization is achieved with a new automated derivatization robot. The D-standard serves as overall internal standard for the whole analytical procedure from sample enrichment to derivatization, chromatography, and response of the detector.

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15

Li, Ka-loh, Xiaoping Zhu, Nola Hylton, Geon-Ho Jahng, Michael W. Weiner, and Norbert Schuff. "Four-phase single-capillary stepwise model for kinetics in arterial spin labeling MRI." Magnetic Resonance in Medicine 53, no. 3 (2005): 511–18. http://dx.doi.org/10.1002/mrm.20390.

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16

Yang, E. Y., and H. L. Moses. "Transforming growth factor beta 1-induced changes in cell migration, proliferation, and angiogenesis in the chicken chorioallantoic membrane." Journal of Cell Biology 111, no. 2 (August 1, 1990): 731–41. http://dx.doi.org/10.1083/jcb.111.2.731.

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Application of TGF beta 1 (10-100 ng) to the chicken chorioallantoic membrane (CAM) for 72 h resulted in a dose-dependent, gross angiogenic response. The vascular effects induced by TGF beta 1 were qualitatively different than those induced by maximal doses of basic FGF (bFGF) (500 ng). While TGF beta 1 induced the formation of large blood vessels by 72 h, bFGF induced primarily small blood vessels. Histologic analysis revealed that TGF beta 1 stimulated pleiotropic cellular responses in the CAM. Increases in fibroblast and epithelial cell density in the area of TGF beta 1 delivery were observed as early as 4 h after TGF beta 1 treatment. By 8 h, these cell types also demonstrated altered morphology and marked inhibition of proliferation as evidenced by 3H-thymidine labeling. Thus, the TGF beta 1-stimulated accumulation of these cell types was the result of cellular chemotaxis from peripheral areas into the area of TGF beta 1 delivery. Microscopic angiogenesis in the form of capillary sprouts and increased endothelial cell density first became evident at 16 h. By 24 h, capillary cords appeared within the mesenchyme of the CAM, extending towards the point of TGF beta 1 delivery. 3H-thymidine labeling revealed that the growth of these capillary cords was due to endothelial cell proliferation. Finally, perivascular mononuclear inflammation did not become evident until 48 h of treatment, and its presence correlated spatially and temporally with the gross and histological remodelling of newly formed capillary cords into larger blood vessels. In summary, these data suggest that, in the chicken CAM, TGF beta 1 initiates a sequence of cellular responses that results in growth inhibition, cellular accumulation through migration, and microvascular angiogenesis.

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Reiner, Michael, Wilhelm Bloch, and Klaus Addicks. "Functional Interaction of Caveolin-1 and eNOS in Myocardial Capillary Endothelium Revealed by Immunoelectron Microscopy." Journal of Histochemistry & Cytochemistry 49, no. 12 (December 2001): 1605–9. http://dx.doi.org/10.1177/002215540104901214.

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Immunogold labeling on samples of isolated perfused rat hearts embedded by an innovative low-temperature LR White procedure provided detailed insight into the interaction of caveolin-1 and endothelial NOS in myocardial capillary endothelium at the subcellular level. Separately, the localization of caveolin-1 and eNOS at caveolae under steady state conditions was visualized. A double-labeling experiment supported their close co-localization. Short-term bradykinin stimulation caused a detectable dissociation of eNOS from caveolin and its redistribution to different cell compartments, whereas caveolin itself remained stationary at caveolae. Morphometric analysis revealed that more than 80% of detectable eNOS was co-localized with caveolin-1 at caveolae under control conditions. After brief stimulation for 2 min with 10-7 M bradykinin, only 26% of the eNOS signals were associated with caveolin-1 and randomly distributed over the endothelial cells. After stimulation, eNOS was found at the plasmalemmal and intracellular membranes, freely in the cytoplasm, and at outer mitochondrial membranes.

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Milkiewicz, Malgorzata, Olga Hudlicka, Margaret D. Brown, and Haley Silgram. "Nitric oxide, VEGF, and VEGFR-2: interactions in activity-induced angiogenesis in rat skeletal muscle." American Journal of Physiology-Heart and Circulatory Physiology 289, no. 1 (July 2005): H336—H343. http://dx.doi.org/10.1152/ajpheart.01105.2004.

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Vascular endothelial growth factor (VEGF) is considered to be important in promotion of capillary growth in skeletal muscles exposed to increased activity. We studied its interactions with nitric oxide (NO) by examining the expression of endothelial NO synthase (NOS), VEGF, and VEGF receptor-2 (VEGFR-2) proteins in relation to capillary growth in rat extensor digitorum longus muscles electrically stimulated for 2, 4, or 7 days with and without NOS inhibition by Nω-nitro-l-arginine (l-NNA, 3 mg/day). Stimulation increased all proteins from 2 days onward, concomitantly with capillary proliferation (labeling for proliferating cell nuclear antigen). Capillary-to-fiber ratio was elevated by 25% after 7 days. Concurrent oral administration of l-NNA did not affect the increase in endothelial NOS but depressed its activity, as shown by increased blood pressure and decreased arteriolar diameters in 2-day-stimulated muscles. NOS inhibition eliminated the increased expression of VEGFR-2 and VEGF proteins in muscles stimulated for 2 and 4 days but not for 7 days. However, it depressed capillary proliferation and the increase in C/F at all time points. We conclude that, in stimulated muscles, NO, generated by activation of neuronal NOS by muscle activity or endothelial NOS by increased blood flow and capillary shear stress, may increase capillary proliferation in the early stages of stimulation through upregulation of VEGFR-2 and VEGF. With longer stimulation, capillary growth appears to require NO, and high levels of VEGF and VEGFR-2 may be contributing to maintenance of the increased capillary bed.

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Bai, Yu, Fuyou Du, Youyou Yang, Yu Bai, and Huwei Liu. "In-capillary non-covalent labeling and determination of tomato systemin with quantum dots in capillary electrophoresis with laser-induced fluorescence detection." Journal of Separation Science 34, no. 20 (September 15, 2011): 2893–900. http://dx.doi.org/10.1002/jssc.201100551.

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Abrahamson, D. R. "Origin of the glomerular basement membrane visualized after in vivo labeling of laminin in newborn rat kidneys." Journal of Cell Biology 100, no. 6 (June 1, 1985): 1988–2000. http://dx.doi.org/10.1083/jcb.100.6.1988.

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To examine the origin and assembly of glomerular basement membranes (GBMs), affinity purified anti-laminin IgG was directly coupled to horseradish peroxidase (HRP) and intravenously injected into newborn rats. Kidneys were then processed for peroxidase histochemistry and microscopy. Within 1 h after injection, anti-laminin bound to basement membranes of nephrons in all developmental stages (vesicle, comma, S-shaped, developing capillary loop, and maturing glomeruli). In S-shaped and capillary loop glomeruli, anti-laminin-HRP labeled a double basal lamina between the endothelium and epithelium. Sections incubated with anti-laminin in vitro showed labeling within the rough endoplasmic reticulum of endothelium and epithelium, indicating that both cell types synthesized laminin for the double basement membrane. In maturing glomeruli, injected anti-laminin-HRP bound throughout the GBMs, and double basement membranes were rarely observed. At this stage, however, numerous knobs or outpockets of basement membrane material extending far into the epithelial side of the capillary wall were identified and these were also labeled throughout their full thickness. No such outpockets were found in the endothelial cell layer of newborn rats (and they normally are completely absent in fully mature, adult glomeruli). In contrast with these results, in kidneys fixed 4-6 d after anti-laminin IgG-HRP injection, basement membranes of vesicle, comma, and S-shaped nephrons were unlabeled, indicating that they were assembled after injection. GBM labeling was seen in maturing glomeruli, however. In addition, the outpockets of basement membrane extending into the epithelium were often completely unlabeled whereas GBMs lying immediately beneath them were labeled intensely, which indicates that the outpockets were probably assembled by the epithelium. Injections of sheep anti-laminin IgG followed 8 d later with injections of biotin-rabbit anti-laminin IgG and double-label immunofluorescence microscopy confirmed that GBM formation continued during individual capillary loop expansion. GBM assembly therefore occurs by at least two different processes at separate times in development: (a) fusion of endothelial and epithelial basement membranes followed by (b) addition of new basement membrane from the epithelium into existing GBMs.

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Anderson, Christopher R., Ana M. Ponce, and Richard J. Price. "Absence of OX-43 antigen expression in invasive capillary sprouts: identification of a capillary sprout-specific endothelial phenotype." American Journal of Physiology-Heart and Circulatory Physiology 286, no. 1 (January 2004): H346—H353. http://dx.doi.org/10.1152/ajpheart.00772.2003.

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Endothelial cells exhibit a number of unique phenotypes, some of which are angiogenesis dependent. To identify a capillary sprout-specific endothelial phenotype, we labeled angiogenic rat mesentery tissue using a microvessel and capillary sprout marker (laminin), selected endothelial cell markers (CD31, tie-2, and BS-I lectin), and the OX-43 monoclonal antibody, which recognizes a 90-kDa membrane glycoprotein of unknown function. In tissues that were stimulated through wound healing and compound 48/80 application, double-immunolabeling experiments with an anti-laminin antibody revealed that the OX-43 antigen was expressed strongly in all microvessels. However, the OX-43 antigen was completely absent from a large percentage (>85%) of the capillary sprouts that were invading the avascular tissue space. In contrast, sprouts that were introverting back into the previously vascularized tissue retained high levels of OX-43 antigen expression. Double-labeling experiments with endothelial markers indicated that the OX-43 antigen was expressed by microvessel endothelium but was absent from virtually all invasive capillary sprout endothelial cells. We conclude that the absence of OX-43 antigen expression marks a novel, capillary sprout-specific, endothelial cell phenotype. Endothelial cells of this phenotype are particularly abundant in capillary sprouts that invade avascular tissue during angiogenesis.

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Diez-Roux, G., M. Argilla, H. Makarenkova, K. Ko, and R. A. Lang. "Macrophages kill capillary cells in G1 phase of the cell cycle during programmed vascular regression." Development 126, no. 10 (May 15, 1999): 2141–47. http://dx.doi.org/10.1242/dev.126.10.2141.

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Programmed capillary regression occurs during normal development of the eye and serves as a useful model for assessing the forces that drive vascular involution. Using a combination of S-phase labeling and liposome-mediated macrophage elimination, we show that during regression, macrophages induce apoptosis of both pericytes and endothelial cells in a cell cycle stage-dependent manner. Target cells are signaled to die by macrophages approximately 15 hours after S-phase labeling and this corresponds to a point in mid-G1 phase of the cell cycle. The tight correlation between the restriction point of the cell cycle and the point where the macrophage death signal is received suggests that the mitogen, matrix and cytoskeletal signals essential for cell-cycle progression may be inhibited by macrophages as a means of inducing cell death. Furthermore, these experiments show that cells from two distinct lineages are induced to die as a consequence of macrophage action, and this provides evidence that macrophage-induced cell death may be a general phenomenon during development and homeostasis.

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Jesmin, Subrina, Yuichi Hattori, Ichiro Sakuma, Chishimba N. Mowa, and Akira Kitabatake. "Role of ANG II in coronary capillary angiogenesis at the insulin-resistant stage of a NIDDM rat model." American Journal of Physiology-Heart and Circulatory Physiology 283, no. 4 (October 1, 2002): H1387—H1397. http://dx.doi.org/10.1152/ajpheart.00299.2002.

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With the use of Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of human non-insulin-dependent diabetes mellitus (NIDDM), we assessed whether ANG II is involved in coronary capillary angiogenesis at the insulin-resistant stage of NIDDM (20 wk of age). In OLETF rats, ANG II labeling and angiotensin type 1 (AT1) receptor expression in coronary vessels were increased more than in nondiabetic controls. A marked increase in vascular expression of vascular endothelial growth factor (VEGF) at both mRNA and protein levels was found in OLETF rats. The increased expression level of VEGF was associated with accumulation of hypoxia-inducible factor-1α (HIF-1α) activated by increased advanced glycation end products (AGEs). Morphometric analysis showed a significantly increased total coronary capillary density, which was a result of arterialization of the venular capillary portion in OLETF rats. Treatment of OLETF rats with candesartan, an AT1receptor blocker, inhibited vascular expressions of VEGF, HIF-1α, and AGEs, and ameliorated the morphometric changes. These results suggest a key role of ANG II in the pathogenesis of the coronary capillary remodeling in this NIDDM model.

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Attiya, Said, Terrina Dickinson-Laing, John Cesarz, Raymond D. Giese, William E. Lee, David Mah, and D. Jed Harrison. "Affinity protection chromatography for efficient labeling of antibodies for use in affinity capillary electrophoresis." ELECTROPHORESIS 23, no. 5 (March 2002): 750–58. http://dx.doi.org/10.1002/1522-2683(200203)23:5<750::aid-elps750>3.0.co;2-3.

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Suma K. V. and Bheemsain Rao. "Detection of Rarefaction of Capillaries and Avascular Region in Nailfold Capillary Images." International Journal of Biomedical and Clinical Engineering 5, no. 2 (July 2016): 73–86. http://dx.doi.org/10.4018/ijbce.2016070106.

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Reduction in the capillary density in the nailfold region is frequently observed in patients suffering from Hypertension (Feng J, 2010). Loss of capillaries results in avascular regions which have been well characterized in many diseases (Mariusz, 2009). Nailfold capillary images need to be pre-processed so that noise can be removed, background can be separated and the useful parameters may be computed using image processing algorithms. Smoothing filters such as Gaussian, Median and Adaptive Median filters are compared using Mean Squared Error and Peak Signal-to-Noise Ratio. Otsu's thresholding is employed for segmentation. Connected Component Labeling algorithm is applied to calculate the number of capillaries per mm. This capillary density is used to identify rarefaction of capillaries and also the severity of rarefaction. Avascular region is detected by determining the distance between the peaks of the capillaries using Euclidian distance. Detection of rarefaction of capillaries and avascular regions can be used as a diagnostic tool for Hypertension and various other diseases.

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Zhou, Chun, Hairu Chen, Judy A. King, Hassan Sellak, Wolfgang M. Kuebler, Jun Yin, Mary I. Townsley, Hee-Sup Shin, and Songwei Wu. "α1GT-type calcium channel selectively regulates P-selectin surface expression in pulmonary capillary endothelium." American Journal of Physiology-Lung Cellular and Molecular Physiology 299, no. 1 (July 2010): L86—L97. http://dx.doi.org/10.1152/ajplung.00331.2009.

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Regulated P-selectin surface expression provides a rapid measure for endothelial transition to a proinflammatory phenotype. In general, P-selectin surface expression results from Weibel-Palade body (WPb) exocytosis. Yet, it is unclear whether pulmonary capillary endothelium possesses WPbs or regulated P-selectin surface expression and, if so, how inflammatory stimuli initiate exocytosis. We used immunohistochemistry, immunofluorescence labeling, ultrastructural assessment, and an isolated perfused lung model to demonstrate that capillary endothelium lacks WPbs but possesses P-selectin. Thrombin stimulated P-selectin surface expression in both extra-alveolar vessel and alveolar capillary endothelium. Only in capillaries was the thrombin-stimulated P-selectin surface expression considerably mitigated by pharmacologic blockade of the T-type channel or genetic knockout of the T-type channel α1G-subunit. Depolarization of endothelial plasma membrane via high K+perfusion capable of eliciting cytosolic Ca2+transients also provoked P-selectin surface expression in alveolar capillaries that was abolished by T-type channel blockade or α1Gknockout. Our findings reveal an intracellular WPb-independent P-selectin pool in pulmonary capillary endothelium, where the regulated P-selectin surface expression is triggered by Ca2+transients evoked through activation of the α1GT-type channel.

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Descroix, Stéphanie, Isabelle Le Potier, Céline Niquet, Nicolas Minc, Jean-Louis Viovy, and Myriam Taverna. "In-capillary non-covalent labeling of insulin and one gastrointestinal peptide for their analyses by capillary electrophoresis with laser-induced fluorescence detection." Journal of Chromatography A 1087, no. 1-2 (September 2005): 203–9. http://dx.doi.org/10.1016/j.chroma.2005.01.095.

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Londono, I., L. Ghitescu, and M. Bendayan. "Glomerular handling of circulating glycated albumin in the normal mouse kidney." American Journal of Physiology-Renal Physiology 268, no. 5 (May 1, 1995): F913—F921. http://dx.doi.org/10.1152/ajprenal.1995.268.5.f913.

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In the present study, we have evaluated the glomerular handling of circulating glycated albumin in the normal mouse kidney by quantitative immunocytochemistry. Bovine serum albumin (BSA) was glycated in vitro and dinitrophenylated. Glycated and nonglycated probes were introduced into the circulation of anesthetized mice and traced by postembedding immunogold cytochemistry after 10 and 30 min of circulation. Endogenous albumin, as well as dinitrophenylated native BSA (DNP-BSA) and glycated albumins (DNP-gBSA), were localized within the capillary lumen, glomerular and peritubular basement membranes, and the mesangial matrix. Morphometric evaluation of the labeling over the glomerular basement membrane (GBM) revealed a peak of labeling in the endothelial side for either endogenous albumin or DNP-BSA. In contrast, the labeling distribution for DNP-gBSA showed a shift toward the epithelial side, suggesting a further penetration of the glycated probe into the GBM. When coinjected with gBSA, DNP-BSA was found to display a labeling distribution similar to that displayed by DNP-gBSA. These results indicate that the glycated tracer penetrates the normal glomerular wall deeper than the nonglycated one. Moreover, glycated albumin increases the infiltration of the nonglycated tracer through the normal glomerular wall. Circulating glycated serum proteins thus appear to play an important role in the onset of the glomerular dysfunction and proteinuria, which take place in long-term hyperglycemic states.

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Volk, Holger, Heidrun Potschka, and Wolfgang Löscher. "Immunohistochemical Localization of P-glycoprotein in Rat Brain and Detection of Its Increased Expression by Seizures Are Sensitive to Fixation and Staining Variables." Journal of Histochemistry & Cytochemistry 53, no. 4 (April 2005): 517–31. http://dx.doi.org/10.1369/jhc.4a6451.2005.

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The MDR1 gene product, P-glycoprotein (P-gp), was shown to confer multi-drug resistance to cancer cells, but its overexpression is also suggested to be involved in pharmacoresistance of epilepsy by acting as an energy-dependent drug-efflux pump in the blood-brain barrier (BBB). In normal brain tissue, P-gp is almost exclusively expressed by capillary endothelial cells (EC) of the BBB, whereas little or no expression is detected in other cell types. Increased P-gp expression was observed after seizures, but localization of this increase, i.e., within brain capillary EC or within parenchymal or perivascular astrocytes, which contribute to the BBB function, is controversial. To test whether these antithetic data arise from unusual properties of the antigen itself, we compared different immunohistochemical techniques and monoclonal or polyclonal antibodies to P-gp in normal rat brain and rat brain after kainate-induced seizures. Using acetone-fixed cryostat sections of snap-frozen tissue, strong P-gp labeling was detected in EC and, after seizures, in hippocampal neurons, but not in astrocytes. In contrast, EC and neuronal P-gp immunolabeling were not seen in paraformaldehyde-fixed sections, whereas both perivascular and parenchymal astrocytes exhibited strong P-gp labeling after seizures. The lack of P-gp labeling in EC by paraformaldehyde fixation, was reversed by treatment of the sections with acetate/ethanol. These experiments demonstrate that various fixation conditions have a striking effect on the immunohistochemical localization of P-gp in rat brain and detection of its increased expression by seizures. When data obtained from different immunohistochemical techniques are taken together, seizures seem to induce overexpression of P-gp in four different cell types, i.e., EC, perivascular astrocytes, parenchymal astrocytes, and neurons.

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Miya, Masaaki, Akito Maeshima, Keiichiro Mishima, Noriyuki Sakurai, Hidekazu Ikeuchi, Takashi Kuroiwa, Keiju Hiromura, and Yoshihisa Nojima. "Age-related decline in label-retaining tubular cells: implication for reduced regenerative capacity after injury in the aging kidney." American Journal of Physiology-Renal Physiology 302, no. 6 (March 15, 2012): F694—F702. http://dx.doi.org/10.1152/ajprenal.00249.2011.

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Recovery after acute kidney injury is impaired in the elderly, but the precise mechanism for such age-related incompetence remains unclear. By in vivo bromodeoxyuridine (BrdU) labeling, renal progenitor cells (label-retaining cells; LRCs) were identified in tubules of normal rat kidney and were shown to be the origin of proliferating cells after injury. In the present study, the involvement of LRCs in the age-related decline of tubular recovery after injury was examined. After 1 wk of BrdU labeling followed by a 2-wk chase period, ischemia-reperfusion injury was induced in 7-wk-, 7-mo-, and 12-mo-old rats. Age-related decreases in DNA synthesis and cell proliferation in renal tubules after injury were found. The number of LRCs also significantly declined with age. At 24 h after reperfusion, the number of LRCs significantly increased in all ages of rats tested. There was no significant difference in the ratio of LRC division among rats of different ages. The area of the rat endothelial cell antigen (RECA)-1-positive capillary network declined with age. When renal tubules isolated from rats treated with BrdU label were cocultured with human umbilical vein endothelial cells (HUVEC), the number of LRCs significantly increased compared with tubules cultured without HUVEC. These data suggest that the reduced capacity of tubular regeneration in the aging kidney is partly explained by the shortage of LRC reserves. The size of the LRC pool might be regulated by the surrounding peritubular capillary network.

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Fujino, Hidemi, Hisaharu Kohzuki, Isao Takeda, Takahiko Kiyooka, Takehiro Miyasaka, Satoshi Mohri, Juichiro Shimizu, and Fumihiko Kajiya. "Regression of capillary network in atrophied soleus muscle induced by hindlimb unweighting." Journal of Applied Physiology 98, no. 4 (April 2005): 1407–13. http://dx.doi.org/10.1152/japplphysiol.00961.2004.

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Little is known about the mechanisms responsible for the adaptation and changes in the capillary network of hindlimb unweighting (HU)-induced atrophied skeletal muscle, especially the coupling between functional and structural alterations of intercapillary anastomoses and tortuosity of capillaries. We hypothesized that muscle atrophy by HU leads to the apoptotic regression of the capillaries and intercapillary anastomoses with their functional alteration in hemodynamics. To clarify the three-dimensional architecture of the capillary network, contrast medium-injected rat soleus muscles were visualized clearly using a confocal laser scanning microscope, and sections were stained by terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL) and with anti-von Willebrand factor. In vivo, the red blood cell velocity of soleus muscle capillaries were determined with a pencil-lens intravital microscope brought into direct contact with the soleus surface. After HU, the total muscle mass, myofibril protein mass, and slow-type myosin heavy chain content were significantly lower. The number of capillaries paralleling muscle fiber and red blood cells velocity were higher in atrophied soleus. However, the mean capillary volume and capillary luminal diameter were significantly smaller after HU than in the age-matched control group. In addition, we found that the number of anastomoses and the tortuosity were significantly lower and TUNEL-positive endothelial cells were observed in atrophied soleus muscles, especially the anastomoses and/or tortuous capillaries. These results indicate that muscle atrophy by HU generates structural alterations in the capillary network, and apoptosis appears to occur in the endothelial cell of the muscle capillaries.

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32

Plock, Jan A., Claudio Contaldo, Hiromi Sakai, Eishun Tsuchida, Michael Leunig, Andrej Banic, Michael D. Menger, and Dominique Erni. "Is hemoglobin in hemoglobin vesicles infused for isovolemic hemodilution necessary to improve oxygenation in critically ischemic hamster skin?" American Journal of Physiology-Heart and Circulatory Physiology 289, no. 6 (December 2005): H2624—H2631. http://dx.doi.org/10.1152/ajpheart.00308.2005.

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The aim of this study was to test the influence of hemoglobin, encapsulated in phospholipid vesicles as an oxygen carrier, given in the course of isovolemic hemodilution to improve oxygenation in critically ischemic hamster flap tissue. Capillary hemodynamics and macromolecular leakage were investigated with intravital microscopy and analyzed off-line with the CapImage software. Partial tissue oxygen tension was measured with fluorescence quenching electrodes. The occurrence of apoptosis was assessed with the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. Vesicles with (HbV) or without (V) encapsulated Hb were suspended in 6% hydroxyethyl starch (HES) used for the 33% blood exchange. In the ischemic tissue, hemodilution led to an increase in functional capillary density by 31% for HES ( P < 0.01 vs. other groups), 66% for V-HES, and 62% for HbV-HES (all P < 0.01 vs. control). Capillary diameters behaved inversely proportional to capillary microhemodynamics. The 20% increase in macromolecular leakage found over time in control animals was completely abolished in the vesicles groups ( P < 0.01) but not with HES. Oxygen tension was improved from 10.7 to 16.0 mmHg after HbV-HES ( P < 0.01 vs. baseline and other groups). Compared with the other groups, apoptosis was significantly reduced after HbV-HES ( P < 0.01). We conclude that the encapsulation of Hb was essential to attenuate hypoxia and subsequent cell death in the critically ischemic tissue. However, the effect was partly attributed to the rheological changes exerted by the vesicles.

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33

Volpi, Nicola. "Capillary electrophoresis determination of glucosamine in nutraceutical formulations after labeling with anthranilic acid and UV detection." Journal of Pharmaceutical and Biomedical Analysis 49, no. 3 (April 2009): 868–71. http://dx.doi.org/10.1016/j.jpba.2009.01.006.

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34

Acket, Sébastien, Anthony Degournay, Mathilde Gosset, Franck Merlier, Manual Adrian Troncoso-Ponce, and Brigitte Thomasset. "Analysis of 13C labeling amino acids by capillary electrophoresis – High resolution mass spectrometry in developing flaxseed." Analytical Biochemistry 547 (April 2018): 14–18. http://dx.doi.org/10.1016/j.ab.2018.02.009.

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35

Zhu, Guimei, Shihua Long, Hao Sun, Wen Luo, Xia Li, and Zaibin Hao. "Determination of gibberellins in soybean using tertiary amine labeling and capillary electrophoresis coupled with electrochemiluminescence detection." Journal of Chromatography B 941 (December 2013): 62–68. http://dx.doi.org/10.1016/j.jchromb.2013.10.004.

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36

Quan, Hong Hua, Ming Li, Yan Huang, and Jong Hoon Hahn. "A hydrophobic ionic liquid compartmentalized sampling/labeling and its separation techniques in polydimethylsiloxane microchip capillary electrophoresis." ELECTROPHORESIS 38, no. 2 (October 31, 2016): 372–79. http://dx.doi.org/10.1002/elps.201600305.

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37

Maunsbach, A. B., D. Marples, E. Chin, G. Ning, C. Bondy, P. Agre, and S. Nielsen. "Aquaporin-1 water channel expression in human kidney." Journal of the American Society of Nephrology 8, no. 1 (January 1997): 1–14. http://dx.doi.org/10.1681/asn.v811.

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The pattern of aquaporin-1 water channel protein (AQP1) expression in the human kidney was analyzed by immunocytochemistry using semi-thin and optimized high-resolution immunoelectron microscopy based on freeze-substituted and Lowicryl HM20 embedded tissue. In addition, in situ hybridization was used to determine AQP1 mRNA distribution. Immunoblots revealed a 28-kd band and a 35- to 45-kd band corresponding to unglycosylated and glycosylated AQP1. Glomerular capillary endothelium exhibited extensive AQP1 labeling, whereas glomerular podocytes and Bowman's capsule epithelium were unlabeled. AQP1 was localized in the proximal tubule, including the neck region directly connected to the glomerulus. However, there was a marked difference in the level of expression between cross-sections of the convoluted part and the proximal straight tubules, the latter displaying the most intense labeling. AQP1 labeling continued uninterrupted from the proximal straight tubule into descending thin limbs in outer medulla. Abrupt transitions from heavily labeled to unlabeled segments of thin limbs were observed, primarily in the inner medulla. This may represent the transition from the water-permeable thin descending limb to the water-impermeable thin ascending limb. In addition, heavy labeling of fenestrated endothelium was also observed in peritubular capillaries in cortex, outer medulla, and inner medulla. Immunolabeling controls were negative. In situ hybridization documented a marked difference in AQP1 mRNA levels within the proximal tubule, with the greatest AQP1 mRNA expression in straight proximal tubules. Glomeruli also showed marked signals, and descending thin limbs exhibited extensive expression in exact concordance with the immunocytochemical results. It was concluded that: (1) AQP1 is present in all proximal tubule segments, including segment 1 and the neck region, but there is a pronounced difference in expression levels with respect to both protein and mRNA levels; (2) AQP1 labeling is observed in the endothelium of fenestrated peritubular capillaries, as well as fenestrated glomerular capillaries; (3) AQP1 labeling continues directly from proximal tubules to descending thin limbs; and (4) abrupt transitions from labeled to unlabeled thin limb epithelium are noted.

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Ghitescu, L., and M. Bendayan. "Transendothelial transport of serum albumin: a quantitative immunocytochemical study." Journal of Cell Biology 117, no. 4 (May 15, 1992): 745–55. http://dx.doi.org/10.1083/jcb.117.4.745.

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The steady-state distribution of endogenous albumin in mouse diaphragm was determined by quantitative postembedding protein A-gold immunocytochemistry using a specific anti-mouse albumin antibody. Labeling density was recorded over vascular lumen, endothelium, junctions, and subendothelial space. At equilibrium, the volume density of interstitial albumin was 18% of that in circulation. Despite this large difference in albumin concentration between capillary lumen and interstitium, plasmalemmal vesicles labeling was uniformly distributed across the endothelial profile. 68% of the junctions displayed labeling for albumin, which was however low and confined to the luminal and abluminal sides. The scarce labeling of the endothelial cell surface did not confirm the fiber matrix theory. The kinetics of albumin transcytosis was evaluated by injecting radioiodinated and DNP-tagged BSA. At 3, 10, 30, and 60 min, and 3, 5, and 24 h circulation time, blood radioactivity was measured and diaphragms were fixed and embedded. Anti-DNP antibodies were used to map the tracer in aforementioned compartments. A linear relationship between blood radioactivity and vascular labeling density was found, with a detection sensitivity approaching 1 gold particle per DNP-BSA molecule. Tracer presence over endothelial vesicles reached rapidly (10 min) a saturation value; initially localized near the luminal front, it evolved towards a uniform distribution across endothelium during the first hour. An hour was also needed to reach the saturation limit within the subendothelial space. Labeling of the junctions increased slowly, out of phase with the inferred transendothelial albumin fluxes. This suggests that they play little, if any, role in albumin transcytosis, which rather seems to proceed through the vesicular way.

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39

Abrahamson, D. R. "Structure and development of the glomerular capillary wall and basement membrane." American Journal of Physiology-Renal Physiology 253, no. 5 (November 1, 1987): F783—F794. http://dx.doi.org/10.1152/ajprenal.1987.253.5.f783.

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The renal glomerular epithelium, Bowman's capsule, and tubule originate from a condensate of mesenchymal cells induced to undergo epithelial differentiation by a branch of the uretic bud. These nephrogenic cells aggregate and begin synthesizing the basement membrane molecules collagen type IV, heparan sulfate proteoglycans, and laminin as shown by immunofluorescence microscopy. Soon, the primitive nephron is invaginated by mesenchymal cells that establish the glomerular endothelium. Electron microscopy, metabolic labeling, and immunocytochemical techniques show that the endothelium and epithelium of early stage glomeruli each synthesize a basement membrane that appears to fuse, giving rise to the glomerular basement membrane (GBM). As development progresses, however, bulk GBM biosynthesis by the endothelium greatly diminishes or ceases. In contrast, GBM assembly by the epithelial podocytes continues and segments of new GBM appear beneath developing foot processes. In vivo labeling experiments with anti-laminin antibodies have shown that this new GBM derived from podocytes is subsequently spliced into existing GBM as capillary loop diameters expand. Molecular mechanisms for basement membrane fusion or splicing are not presently known but may involve partial enzymatic digestion and specific binding interactions among GBM components. The developing glomerular capillary wall, which filters plasma from very early stages, becomes decreasingly permeable to perfused macromolecules such as ferritin or immunoglobulin as the glomerulus matures. Evidence from immunolabeling studies showing that some monoclonal IgGs bind to the GBM only at specific developmental stages also indicates that temporal biochemical changes take place during GBM assembly. Such changes could include molecular rearrangement during basement membrane fusion and splicing and/or enzymatic and compositional modifications during maturation of the filtration barrier.

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40

Khorsandi, Saeid, Liwei Li, and Russell T. Johns. "A New Way of Compositional Simulation without Phase Labeling." SPE Journal 26, no. 02 (February 10, 2021): 940–58. http://dx.doi.org/10.2118/190269-pa.

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Summary Current relative permeability models rely on labeling a phase as “oil” and “gas” and cannot therefore capture accurately the effect of compositional variations on relative permeabilities and capillary pressures in enhanced oil recovery processes. Discontinuities in flux calculations caused by phase labeling problems not only cause serious convergence and stability problems but also affect the estimated recovery factor owing to incorrect phase mobilities. We developed a fully compositional simulation model using an equation of state (EoS) for relative permeabilities (kr) to eliminate the unphysical discontinuities in flux functions caused by phase labeling issues. The model can capture complex compositional and hysteresis effects for three-phase relative permeability. Each phase is modeled separately based on physical inputs that, in part, are proxies to composition. Phase flux calculations from one gridblock to another are also updated without phase labels. The tuned kr-EoS model and updated compositional simulator are demonstrated for simple ternary cases, multicycle three-phase water-alternating-gas (WAG) injection, and three-hydrocarbon-phase displacement with complex heterogeneity. The approach improves the initial estimates and convergence of flash calculations and stability analyses, as well as the convergence in the pressure solvers. The new compositional simulator allows for high-resolution simulation that gives improved accuracy in recovery estimates at significantly reduced computational time.

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41

Grazul-Bilska, Anna T., Pawel P. Borowicz, Mary Lynn Johnson, Megan A. Minten, Jerzy J. Bilski, Robert Wroblewski, Dale A. Redmer, and Lawrence P. Reynolds. "Placental development during early pregnancy in sheep: vascular growth and expression of angiogenic factors in maternal placenta." REPRODUCTION 140, no. 1 (July 2010): 165–74. http://dx.doi.org/10.1530/rep-09-0548.

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Placental vascular development (angiogenesis) is critical for placental function and thus for normal embryonic/fetal growth and development. Specific environmental factors or use of assisted reproductive techniques may result in poor placental angiogenesis, which may contribute to embryonic losses and/or fetal growth retardation. Uterine tissues were collected on days 14, 16, 18, 20, 22, 24, 26, 28, and 30 after mating and on day 10 after estrus (nonpregnant controls) to determine vascular development and expression of several factors involved in the regulation of angiogenesis in the endometrium. Compared with controls, several measurements of endometrial vascularity increased (P<0.001) including vascular labeling index (LI; proportion of proliferating cells), the tissue area occupied by capillaries, area per capillary (capillary size), total capillary circumference per unit of tissue area, and expression of factor VIII (marker of endothelial cells), but capillary number decreased (P<0.001). Compared with controls, mRNA for placental growth factor, vascular endothelial growth factor receptors, angiopoietins (ANGPT) 1 and 2, ANGPT receptorTEK, endothelial nitric oxide synthase, and hypoxia-inducible factor 1α increased (P<0.05) during early pregnancy. Vascular LI was positively correlated (P<0.05) with several measurements of vascularity and with mRNA expression of angiogenic factors. These data indicate that endometrial angiogenesis, manifested by increased vascularity and increased expression of several factors involved in the regulation of angiogenesis, is initiated very early in pregnancy. This more complete description of early placental angiogenesis may provide the foundation for determining whether placental vascular development is altered in compromised pregnancies.

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42

Schul, David, Daniel Tallmadge, Derek Burress, Deborah Ewald, Belinda Berger, and David Henry. "Determination of Fat in Olestra-Containing Savory Snack Products by Capillary Gas Chromatography." Journal of AOAC INTERNATIONAL 81, no. 4 (July 1, 1998): 848–68. http://dx.doi.org/10.1093/jaoac/81.4.848.

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Abstract A quantitative method to determine fat in olestra-containing savory snack products was validated within the AOAC Peer-Verified Methods Program. The method may be used to demonstrate compliance with the guidelines of the U.S. Nutrition Labeling and Education Act for labeling products as "fat free" or "low fat." The method can measure total and saturated fat in savory snacks when present at levels of 0.2-10 g total fat and 0.1-3 g saturated fat per 30 g serving. The method is standardized to measure C6- C24 fatty acids. Extraction of olestra-containing savory snack samples with chloroform-methanol (modified AOAC Official Method 983.23) yields a lipid extract containing the total fat and olestra. The extracted lipid is hydrolyzed by lipase, yielding fatty acids and unreacted olestra. The fatty acids are precipitated as calcium soaps. Olestra is extracted from insoluble soaps with hexane and then discarded. The isolated soaps are converted back into fatty acids with hydrochloric acid and extracted with hexane. The isolated fatty acids are converted to methyl esters with boron trifluoride-methanol and quantitated by capillary gas chromatography using internal standard. Test samples were prepared by blending olestra-containing and full-fat (triglyceride) snacks to obtain 6 levels of spiking (0-10 g total fat added/30 g serving) in potato chips, potato crisps, cheese puffs, and nacho cheese-flavored corn chips. Results were linear (r2 > 0.997) between 0 and 10 g fat/30 g serving for each product matrix. Mean recovery was 101 6% standard deviation (SD) for total fat and 104 ± 6% SD for saturated fat. Mean recovery by peer laboratory was 88 ± 5% SD for total fat and 95 ± 4% SD for saturated fat in potato chips (0-3 g total fat added/30 g serving). Two sets of 10 replicates of potato chips (0.5 g total fat/30 g serving and 0.16 g saturated fat/30 g serving) and potato crisps (0.5 g total fat/30 g serving and 0.16 g saturated fat/30 g serving) were analyzed by submitting and peer laboratories. Repeatability relative standard deviations ranged from 3.90 to 7.33% for total fat and from 4.01 to 11.53% for saturated fat. Reproducibility relative standard deviations were 7.33% (total fat, potato chips), 7.15% (total fat, potato crisps), 11.36% (saturated fat, potato chips), and 13.50% (saturated fat, potato crisps)

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Coulombe, P. A., and M. Bendayan. "Cytochemical demonstration of increased phospholipid content in cell membranes in chlorphentermine-induced phospholipidosis." Journal of Histochemistry & Cytochemistry 37, no. 2 (February 1989): 139–47. http://dx.doi.org/10.1177/37.2.2911004.

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We recently introduced a novel cytochemical approach to high-resolution cytochemistry of phospholipids in biological tissues. The technique consists of adsorption of bee venom phospholipase A2 to colloidal gold particles (PLA2-gold complex) and subsequent application of this complex for localization of the enzyme substrate, i.e., glycerophospholipids. In the present study, this technique was applied at the post-embedding level, in both light (LM) and transmission electron microscopy (TEM), to investigate drug-induced phospholipidosis, an experimental disorder in which the lysosomal catabolism of phospholipids is inhibited. Rats received one week of daily treatment (40 mg IP/kg) with chlorphentermine (CP), a cationic amphiphilic drug known to induce phospholipidosis in several tissues. Glutaraldehyde- and osmium-fixed lung and kidney tissues from both treated and control animals, were embedded in Epon and sections processed for labeling by PLA2-gold. In CP-treated specimens the presence of large osmiophilic inclusions in several cell types of lung parenchyma and kidney cortex confirmed the onset of phospholipidosis. These inclusions were densely labeled by PLA2-gold at both LM and TEM levels. Two general types of abnormal inclusions were distinguished on the basis of their ultrastructure and labeling pattern by PLA2-gold, suggesting different content or configuration of phospholipids. Moreover, quantitative evaluation of labeling density over various membrane compartments in lung alveolar cells evidenced significantly increased phospholipid content after CP treatment. In type II pneumocytes, such increases were measured in membranes of the RER, Golgi complex, outer and inner nuclear envelope, and the basolateral and apical domains of the plasma membrane. In capillary endothelial cells, the basal and luminal domains of the plasma membrane also showed an increase in labeling density. These results further demonstrate the potential usefulness of the PLA2-gold technique for in situ ultrastructural localization of phospholipids in normal and pathological tissues.

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Starke, Heather R., Ju Ying Yan, Jian Zhong Zhang, Klaus Muhlegger, Klaus Effgen, and Norman J. Dovichi. "Internal fluorescence labeling with fluorescent deoxynucleotides in two-label peak-height encoded DNA sequencing by capillary electrophoresis." Nucleic Acids Research 22, no. 19 (1994): 3997–4001. http://dx.doi.org/10.1093/nar/22.19.3997.

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OHASHI, RYUJI, HIROSHI KITAMURA, and NOBUAKI YAMANAKA. "Peritubular Capillary Injury during the Progression of Experimental Glomerulonephritis in Rats." Journal of the American Society of Nephrology 11, no. 1 (January 2000): 47–56. http://dx.doi.org/10.1681/asn.v11147.

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Abstract. The functional and morphologic changes occurring in the peritubular capillaries (PTC) of the kidney during the progression of renal disease are not yet completely understood. In this study, the features of PTC disruption observed in a rat anti-glomerular basement membrane-induced glomerulonephritis (GN) model were characterized. Contributions to the progression of the disease made by other interstitial components, including ED-1-positive macrophages and CD3-positive T cells, were also investigated. Within 7 d of inducing GN, severe necrotizing glomerular injuries were observed. Thrombomodulin staining revealed that within 3 to 8 wk, there was a significant (P < 0.001) decline in the number of PTC, accompanied by a marked accumulation of macrophages, T cells, and fibrotic material. By the end of this period, most PTC were severely damaged or lost, and tubulointerstitial scarring was noted in the affected areas. Furthermore, PTC endothelial cell apoptosis occurred concomitantly, as shown by application of terminal deoxynucleotidyl transferasemediated dUTP-biotin nick end labeling methods and electron microscopy. It was presumed that the PTC injury was mediated possibly by the infiltrating macrophages and T cells, which, together with destruction of the PTC structure, correlated significantly with the impairment of renal function. These findings suggest that PTC disruption and the subsequent regression of the capillary network may contribute to the development of the tubulointerstitial injury largely responsible for the renal dysfunction in progressive GN.

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Brasch, Frank, Marion Neckel, Rolf Volkmann, Gerhard Schmidt, Gerhard Hellige, and Friedrich Vetterlein. "Mapping of capillary flow, cellular redox state, and resting membrane potential in hypoperfused rat myocardium." American Journal of Physiology-Heart and Circulatory Physiology 277, no. 5 (November 1, 1999): H2050—H2064. http://dx.doi.org/10.1152/ajpheart.1999.277.5.h2050.

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The influence on myocyte viability of ischemia-induced changes in capillary perfusion was studied in the hearts of anesthetized rats subjected to partial occlusion of the left coronary artery for 45 min. Timed plasma labeling was applied to determine perfusion patterns. Changes in the fluorescence of preloaded potential-sensitive dyes [tetramethylrhodamine methyl ester (TMRM) and bis-oxonol], of trypan blue, and of endogeneous NADH were utilized in characterizing myocyte viability in histological sections of the heart. Within the hypoperfused zone, localized areas appeared vascularly nonlabeled for periods of at least 10 min. Within these areas a reduction in TMRM fluorescence occurred in 82.5% of the tissue, signaling a reduced resting membrane potential. In the same areas 37.7% of the myocytes revealed an NADH fluorescence lower than that regularly found in anoxic tissues. This correlated with an especially low level of TMRM, with increased fluorescence bis-oxonol and with an accumulation of trypan blue. In conclusion, in localized hypoperfusion-induced zones lacking capillary flow, an inhomogeneous pattern of reductions in myocyte viability develops, which appears to be relevant in ischemia-induced arrhythmias.

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Bendayan, M., and E. A. Rasio. "Transport of insulin and albumin by the microvascular endothelium of the rete mirabile." Journal of Cell Science 109, no. 7 (July 1, 1996): 1857–64. http://dx.doi.org/10.1242/jcs.109.7.1857.

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Vascular permeability for albumin and insulin in the continuous capillary network of the rete mirabile of the eel swimbladder was evaluated by ultrastructural immunocytochemistry and countercurrent perfusion experiments. Upon perfusion of the rete capillaries with a buffer solution containing albumin and insulin, these serum proteins were revealed at the electron microscope level, by the Protein A-gold immunocytochemical technique on a post-embedding step. For the simultaneous detection of both proteins, the double labeling technique with different sized gold particles was used. Furthermore, labeling was performed with the mixture of anti-albumin and anti-insulin anti-bodies. The labelings obtained were morphometrically evaluated and demonstrate that: (1) serum proteins such as albumin and insulin are transported by the endothelial cells through their plasmalemmal vesicular system; (2) insulin is transported preferentially to albumin; and (3) this transport involves different populations of plasmalemmal vesicles. Measurements of diffusion permeability coefficients have confirmed the preferential transport of insulin, its coefficient being higher than that of albumin. Conversely, when compared to that of insulin or sucrose, which are assumed to be markers of the paracellular diffusion, it was found to be much lower, indicating that transcytosis through the vesicular system is less efficient than diffusion along the intercellular junctions. These results indicate that transcytosis of insulin and albumin occurs via different sets of plasmalemmal vesicles, probably through receptor-mediated mechanisms, and that the overall rate of transport across the rete capillaries, with respect to paracellular diffusion, is higher for insulin than for albumin.

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48

Hellstrom, M., M. Kal n, P. Lindahl, A. Abramsson, and C. Betsholtz. "Role of PDGF-B and PDGFR-beta in recruitment of vascular smooth muscle cells and pericytes during embryonic blood vessel formation in the mouse." Development 126, no. 14 (July 15, 1999): 3047–55. http://dx.doi.org/10.1242/dev.126.14.3047.

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Development of a vascular system involves the assembly of two principal cell types - endothelial cells and vascular smooth muscle cells/pericytes (vSMC/PC) - into many different types of blood vessels. Most, if not all, vessels begin as endothelial tubes that subsequently acquire a vSMC/PC coating. We have previously shown that PDGF-B is critically involved in the recruitment of pericytes to brain capillaries and to the kidney glomerular capillary tuft. Here, we used desmin and alpha-smooth muscle actin (ASMA) as markers to analyze vSMC/PC development in PDGF-B−/− and PDGFR-beta−/− embryos. Both mutants showed a site-specific reduction of desmin-positive pericytes and ASMA-positive vSMC. We found that endothelial expression of PDGF-B was restricted to immature capillary endothelial cells and to the endothelium of growing arteries. BrdU labeling showed that PDGFR-beta-positive vSMC/PC progenitors normally proliferate at sites of endothelial PDGF-B expression. In PDGF-B−/− embryos, limb arterial vSMC showed a reduced BrdU-labeling index. This suggests a role of PDGF-B in vSMC/PC cell proliferation during vascular growth. Two modes of vSMC recruitment to newly formed vessels have previously been suggested: (1) de novo formation of vSMC by induction of undifferentiated perivascular mesenchymal cells, and (2) co-migration of vSMC from a preexisting pool of vSMC. Our data support both modes of vSMC/PC development and lead to a model in which PDGFR-beta-positive vSMC/PC progenitors initially form around certain vessels by PDGF-B-independent induction. Subsequent angiogenic sprouting and vessel enlargement involves PDGF-B-dependent vSMC/PC progenitor co-migration and proliferation, and/or PDGF-B-independent new induction of vSMC/PC, depending on tissue context.

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49

Simon, H., Y. Gao, N. Franki, and R. M. Hays. "Vasopressin depolymerizes apical F-actin in rat inner medullary collecting duct." American Journal of Physiology-Cell Physiology 265, no. 3 (September 1, 1993): C757—C762. http://dx.doi.org/10.1152/ajpcell.1993.265.3.c757.

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In amphibian bladder, arginine vasopressin (AVP) depolymerizes F-actin in the apical region of the granular cell, promoting fusion of water channel-carrying vesicles with the apical membrane. We now report the effect of AVP on F-actin in the mid- and terminal segments of rat inner medullary collecting duct (IMCD2 and IMCD3). In IMCD3, 5 min of stimulation by 2.5-250 nM AVP significantly depolymerized F-actin by 13-24% in whole cell assays employing the rhodamine-phalloidin binding technique. The IMCD2 was more sensitive, responding to subnanomolar (0.25 nM) AVP with 6 +/- 2% depolymerization. Depolymerization occurred as early as 2 min after 2.5 and 25 nM but not 250 nM AVP. 8-Bromoadenosine 3',5'-cyclic monophosphate depolymerized F-actin in IMCD3 at both 2 and 5 min. Immunogold labeling of the apical actin pool in IMCD3 principal cells was reduced by 26 +/- 5% (P < 0.05) by 2.5 nM AVP; the lateral and basal pools showed no significant changes. Capillary endothelial, thin limb of Henle, and intercalated cells showed no changes in immunogold labeling after AVP. Thus reorganization of the apical actin network by AVP is a consistent finding in both mammalian and amphibian target cells.

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50

Malanga, Milo, Mihály Bálint, István Puskás, Kata Tuza, Tamás Sohajda, László Jicsinszky, Lajos Szente, and Éva Fenyvesi. "Synthetic strategies for the fluorescent labeling of epichlorohydrin-branched cyclodextrin polymers." Beilstein Journal of Organic Chemistry 10 (December 16, 2014): 3007–18. http://dx.doi.org/10.3762/bjoc.10.319.

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The fluorescent tagging of cyclodextrin derivatives enlarges their spectroscopic properties thus generating chemosensors, biological tools for visualization and sophisticated photoresponsive devices. Cyclodextrin polymers, due to the cooperative interactions, exhibit additional properties compared to their monomeric counterpart. These macromolecules can be prepared either in well water-soluble form or as gels of high swelling. Two versatile synthetic strategies for introducing a fluorescent tag (rhodamine, fluorescein, nitrobenzofuran or coumarin) into the water-soluble epichlorohydrin branched cyclodextrin polymers were worked out and compared. The fluorescent labeling was realized in three steps: 1) building in azido moieties, 2) transforming the azido groups into amino groups and 3) coupling the proper fluorescent compound to the amino groups. The other strategy started by functionalization of the monomer prior to the branching. Either the fluorescent-labeled monomer or the intermediate azido derivative of the monomer was branched. Further tuning of the properties of the polymer was achieved via branching of the methylated cyclodextrin derivative. The key intermediates and the fluorescent final products were characterized by various spectroscopic techniques and capillary electrophoresis. The applied synthetic routes were evaluated based on the molecular weight, cyclodextrin content of the products and the efficiency of labeling.

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Journal articles on the topic 'In-Capillary labeling'

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