WorldWideScience

Sample records for blood vessel density

  1. Examining blood vessels

    International Nuclear Information System (INIS)

    This patent specification relates to an invention concerned with improvements in or relating to the examination of blood vessels of interest. Particles of dimensions not greater than 8 microns capable of providing detectable signals, are introduced into the blood for examination of a blood vessel. The particles may be sources of radiation, e.g. Ga68. (author)

  2. Evaluation of local density enhancement of microcapsules in artificial blood vessel during exposure to focused ultrasound

    International Nuclear Information System (INIS)

    We have proposed a physical DDS (Drug Delivery System) which makes use of microcapsules of μm size, which may contain a specified drug and also are easily affected by ultrasound exposure near their resonant frequency, to release various kinds of medications. These capsules are easily detected and actuated by ultrasound. However, because of the diffusion of capsules after injection into human body, it was difficult to enhance the efficiency of drug delivery. Thus we have considered a method for controlling the density of capsules in flow which uses acoustic radiation force, which moves the capsules to balance flow resistance. We have experimented with trapping microcapsules or microbubbles in flow of an artificial blood vessel. We have evaluated the effect of radiation force by measuring the trapped area of capsules or bubbles for various frequencies, sound pressures, and exposure times of sinusoidal ultrasound. The trapped area of capsules or bubbles increased with sound pressure and exposure time, and decreased with frequency. From those results, we have derived optimal conditions for trapping the capsules or bubbles.

  3. Evaluation of local density enhancement of microcapsules in artificial blood vessel during exposure to focused ultrasound

    Science.gov (United States)

    Nakamoto, Ryusuke; Masuda, Kohji; Watarai, Nobuyuki; Taguchi, Yuto; Kato, Toshikazu; Yoshinaga, Takashi; Miyamoto, Yoshitaka; Chiba, Toshio

    2011-09-01

    We have proposed a physical DDS (Drug Delivery System) which makes use of microcapsules of μm size, which may contain a specified drug and also are easily affected by ultrasound exposure near their resonant frequency, to release various kinds of medications. These capsules are easily detected and actuated by ultrasound. However, because of the diffusion of capsules after injection into human body, it was difficult to enhance the efficiency of drug delivery. Thus we have considered a method for controlling the density of capsules in flow which uses acoustic radiation force, which moves the capsules to balance flow resistance. We have experimented with trapping microcapsules or microbubbles in flow of an artificial blood vessel. We have evaluated the effect of radiation force by measuring the trapped area of capsules or bubbles for various frequencies, sound pressures, and exposure times of sinusoidal ultrasound. The trapped area of capsules or bubbles increased with sound pressure and exposure time, and decreased with frequency. From those results, we have derived optimal conditions for trapping the capsules or bubbles.

  4. Blood Vessels in Allotransplantation.

    Science.gov (United States)

    Abrahimi, P; Liu, R; Pober, J S

    2015-07-01

    Human vascularized allografts are perfused through blood vessels composed of cells (endothelium, pericytes, and smooth muscle cells) that remain largely of graft origin and are thus subject to host alloimmune responses. Graft vessels must be healthy to maintain homeostatic functions including control of perfusion, maintenance of permselectivity, prevention of thrombosis, and participation in immune surveillance. Vascular cell injury can cause dysfunction that interferes with these processes. Graft vascular cells can be activated by mediators of innate and adaptive immunity to participate in graft inflammation contributing to both ischemia/reperfusion injury and allograft rejection. Different forms of rejection may affect graft vessels in different ways, ranging from thrombosis and neutrophilic inflammation in hyperacute rejection, to endothelialitis/intimal arteritis and fibrinoid necrosis in acute cell-mediated or antibody-mediated rejection, respectively, and to diffuse luminal stenosis in chronic rejection. While some current therapies targeting the host immune system do affect graft vascular cells, direct targeting of the graft vasculature may create new opportunities for preventing allograft injury and loss. PMID:25807965

  5. 2013 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  6. 2013 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  7. 2013 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  8. 2013 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  9. 2013 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  10. 2011 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  11. 2011 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  12. 2011 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  13. 2011 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  14. 2011 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  15. Blood vessels, circulation and blood pressure.

    Science.gov (United States)

    Hendry, Charles; Farley, Alistair; McLafferty, Ella

    This article, which forms part of the life sciences series, describes the vessels of the body's blood and lymphatic circulatory systems. Blood pressure and its regulatory systems are examined. The causes and management of hypertension are also explored. It is important that nurses and other healthcare professionals understand the various mechanisms involved in the regulation of blood pressure to prevent high blood pressure or ameliorate its damaging consequences.

  16. Correlations Between the Density of Tryptase Positive Mast Cells (DMCT) and that of New Blood Vessels (CD105+) in Patients with Gastric Cancer.

    Science.gov (United States)

    Micu, Gianina Viorica; Stăniceanu, Florica; Sticlaru, Liana Cătălina; Popp, Cristiana Gabriela; Bastian, Alexandra Eugenia; Gramada, Eliza; Pop, G; Mateescu, R B; Rimbaş, M; Archip, Bianca; Bleotu, Coralia

    2016-06-01

    Mast cells proteases, tryptase and chymase are directly involved in the growth and progression of solid tumors due to their important role in tumor angiogenesis. We examined the density of tryptase positive mast cells and the mean density of new blood vessels in gastric malignant tumors of patients with and without Helicobacter pylori infection, using immunohistochemical staining for tryptase (for mast cells) and CD 105 (for new vessels). Tryptase and CD 105 expression was detected in gastrectomy specimens. In this study, mast cell density correlates with angiogenesis and the growth and progression of gastric cancer. It also shows that the participation of Helicobacter pylori infection in the growth and progress of gastric neoplasia is due to an increase of peritumoral angiogenesis, with subsequent local and distant tumor spread and perivascular growth, but without perineural and nodal involvement. PMID:27352440

  17. Correlations Between the Density of Tryptase Positive Mast Cells (DMCT and that of New Blood Vessels (CD105+ in Patients with Gastric Cancer

    Directory of Open Access Journals (Sweden)

    Micu Gianina Viorica

    2016-06-01

    Full Text Available Mast cells proteases, tryptase and chymase are directly involved in the growth and progression of solid tumors due to their important role in tumor angiogenesis. We examined the density of tryptase positive mast cells and the mean density of new blood vessels in gastric malignant tumors of patients with and without Helicobacter pylori infection, using immunohistochemical staining for tryptase (for mast cells and CD 105 (for new vessels. Tryptase and CD 105 expression was detected in gastrectomy specimens. In this study, mast cell density correlates with angiogenesis and the growth and progression of gastric cancer. It also shows that the participation of Helicobacter pylori infection in the growth and progress of gastric neoplasia is due to an increase of peritumoral angiogenesis, with subsequent local and distant tumor spread and perivascular growth, but without perineural and nodal involvement.

  18. [Pulmonary blood vessels in goats].

    Science.gov (United States)

    Roos, H; Hegner, K; Vollmerhaus, B

    1999-05-01

    The blood vessels in the lung of the goat, which until now have received little attention, are described in detail for the first time. With regard to the segments of the lung, blood vessels are bronchovascular units in the lobi craniales, lobus medius and lobus accessorius, but bronchoartery units in the lobi caudales. We investigated the types of branches of the Aa. pulmonales dextra et sinistra, the inter- and intraspecific principles of the outlet of the pulmonary veins and the importance of bronchopulmonary segmentation of the lungs. PMID:10386009

  19. Tea May Benefit Blood Vessels

    Institute of Scientific and Technical Information of China (English)

    华剑铭

    2000-01-01

    读到有关饮茶有益健康的消息,我总是充满了自豪感:茶的故乡毕竟在中国。饮茶对人的心脏有益,这已经不是新闻,但是到底如何起到此类保健作用,多年来一直是一个谜。本文揭开了此谜底: Drinking a cup of tea makes blood vessels work better within 2 hours, dilating(扩张)the arteries(动脉)and improving blood flow. 文章令我感动之处在于那些科研人员的敬业精神。比如茶中含有caffeine(咖啡因),饮茶对心脏有利,此“利”是否源于caffeine呢?试验人员为了弄清这 一点,便让另一组受试人员服用等量的caffeine,结果证实:Caffeine had no response on the blood vessel function.】

  20. Correlation between expressions of hypoxia -inducible factor (HIF-1α, blood vessels density, cell proliferation, and apoptosis intensity in canine fibromas and fibrosarcomas

    Directory of Open Access Journals (Sweden)

    Madej Janusz A.

    2014-03-01

    Full Text Available The study aimed to demonstrate the expression of hypoxia-inducible factor (HIF-1α in soft tissue mesenchymal tumours (fibroma and fibrosarcoma in dogs. An attempt was made to correlate the obtained results with density of blood vessels (expression of von Willebrand Factor, vWF, expression of Ki-67 proliferation antigen, and with intensity of apoptosis in studied tumours. The study was performed on paraffin sections of 15 fibromas and 40 fibrosarcomas sampled from 55 female dogs aged 6 to 16 years. Immunohistochemical staining against HIF-1α, vWF, and Ki-67 was performed. Apoptosis was detected with the use of TUNEL reaction. A significantly higher HIF-1α expression was noted in fibrosarcomas in comparison to fibromas (P < 0.0001. HIF-1α expression in fibromas manifested strong positive correlation with tumour vascularity (r = 0.67, P = 0.007. Moreover, HIF-1α expression in fibrosarcomas manifested a moderate positive correlation with tumour malignancy grade (r = 0.44, P = 0.004, tumour vascularity (r = 0.52, P < 0.001, Ki-67 antigen expression (r = 0.42; P = 0.007, and TUNELpositive cells (r = 0.37, P = 0.017. Expression of HIF-1α was detected in 86.7% of fibroma type tumours and in 100% of fibrosarcomas. In all studied tumours expression of HIF-1α manifested positive correlation with the density of blood vessels, and in fibrosarcomas it correlated also with malignancy grade, intensity of Ki-67 expression, and with intensity of apoptosis in tumour cells.

  1. Photoacoustic determination of blood vessel diameter

    Science.gov (United States)

    Kolkman, Roy G. M.; Klaessens, John H. G. M.; Hondebrink, Erwin; Hopman, Jeroen C. W.; de Mul, Frits F. M.; Steenbergen, Wiendelt; Thijssen, Johan M.; van Leeuwen, Ton G.

    2004-10-01

    A double-ring sensor was applied in photoacoustic tomographic imaging of artificial blood vessels as well as blood vessels in a rabbit ear. The peak-to-peak time (tgrpp) of the laser (1064 nm) induced pressure transient was used to estimate the axial vessel diameter. Comparison with the actual vessel diameter showed that the diameter could be approximated by 2ctgrpp, with c the speed of sound in blood. Using this relation, the lateral diameter could also precisely be determined. In vivo imaging and monitoring of changes in vessel diameters was feasible. Finally, acoustic time traces were recorded while flushing a vessel in the rabbit ear with saline, which proved that the main contribution to the laser-induced pressure transient is caused by blood inside the vessel and that the vessel wall gives only a minor contribution.

  2. Photoacoustic determination of blood vessel diameter

    International Nuclear Information System (INIS)

    A double-ring sensor was applied in photoacoustic tomographic imaging of artificial blood vessels as well as blood vessels in a rabbit ear. The peak-to-peak time (τpp) of the laser (1064 nm) induced pressure transient was used to estimate the axial vessel diameter. Comparison with the actual vessel diameter showed that the diameter could be approximated by 2cτpp, with c the speed of sound in blood. Using this relation, the lateral diameter could also precisely be determined. In vivo imaging and monitoring of changes in vessel diameters was feasible. Finally, acoustic time traces were recorded while flushing a vessel in the rabbit ear with saline, which proved that the main contribution to the laser-induced pressure transient is caused by blood inside the vessel and that the vessel wall gives only a minor contribution

  3. Methotrexate reduces hippocampal blood vessel density and activates microglia in rats but does not elevate central cytokine release

    NARCIS (Netherlands)

    Seigers, Riejanne; Timmermans, Jessica; van der Horn, Hans J.; de Vries, Erik F. J.; Dierckx, Rudi A.; Visser, Lydia; Schagen, Sanne B.; van Dam, Frits S. A. M.; Koolhaas, Jaap M.; Buwalda, Bauke

    2010-01-01

    Methotrexate is a cytostatic drug applied in adjuvant chemotherapy and associated with cognitive impairment in part of the cancer patients. In this paper we studied in rats whether a reduction in blood supply to the brain or neuroinflammation are possible mediators of this cognitive dysfunctionality

  4. Robust RANSAC-based blood vessel segmentation

    Science.gov (United States)

    Yureidini, Ahmed; Kerrien, Erwan; Cotin, Stéphane

    2012-02-01

    Many vascular clinical applications require a vessel segmentation process that is able to extract both the centerline and the surface of the blood vessels. However, noise and topology issues (such as kissing vessels) prevent existing algorithm from being able to easily retrieve such a complex system as the brain vasculature. We propose here a new blood vessel tracking algorithm that 1) detects the vessel centerline; 2) provides a local radius estimate; and 3) extracts a dense set of points at the blood vessel surface. This algorithm is based on a RANSAC-based robust fitting of successive cylinders along the vessel. Our method was validated against the Multiple Hypothesis Tracking (MHT) algorithm on 10 3DRA patient data of the brain vasculature. Over 744 blood vessels of various sizes were considered for each patient. Our results demonstrated a greater ability of our algorithm to track small, tortuous and touching vessels (96% success rate), compared to MHT (65% success rate). The computed centerline precision was below 1 voxel when compared to MHT. Moreover, our results were obtained with the same set of parameters for all patients and all blood vessels, except for the seed point for each vessel, also necessary for MHT. The proposed algorithm is thereafter able to extract the full intracranial vasculature with little user interaction.

  5. Complete Blood Count and Retinal Vessel Calibers

    OpenAIRE

    Liew, Gerald; Wang, Jie Jin; Rochtchina, Elena; Wong, Tien Yin; Mitchell, Paul

    2014-01-01

    Objective The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers. Methods Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at...

  6. 2011 Tug Towing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  7. Over-expression of Slit2 induces vessel formation and changes blood vessel permeability in mouse brain

    Institute of Scientific and Technical Information of China (English)

    Hai-xiong HAN; Jian-guo GENG

    2011-01-01

    Aim:To investigate the effect of the axon guidance cue Slit2 on the density of blood vessels and permeability of the blood-brain barrier in mouse brain.Methods:hSlit2 transgenic mouse line was constructed,and the phenotypes of the mice were compared with wild-type mice in respect to the lateral ventricle (LV),ventricle pressure,and the choroids plexus.An in vivo Miles permeability assay and an amyloid-β permeability assay were used to assess the permeability of brain blood vessels.Brain vessel casting and intracerebral hemorrhage models were built to investigate vessel density in the transgenic mice.An in vitro permeability assay was used to test whether Slit2 could change the permeability and tight junctions of blood vessel endothelial cells.Results:Hydrocephalus occurred in some transgenic mice,and a significantly larger lateral ventricle area and significantly higher ventricle pressure were observed in the transgenic mice.The transgenic mice displayed changed construction of the choroids plexus,which had more micro vessels,dilated vessels,gaps between epithelial cells and endothelial cells than wild-type mice.Slit2 significantly increased brain vessel density and the permeability of brain vessels to large molecules.These blood vessels were more sensitive to cues that induce brain hemorrhage.At the cellular level,Slit2 disturbed the integrity of tight junctions in blood vessel endothelial cells and improved the permeability of the endothelial cell layer.Thus,it promoted the entry of amyloid-β peptides from the serum into the central nervous system,where they bound to neurons.Conclusion:Slit2 increases vessel density and permeability in the brains of transgenic mice.Thus,Slit2 induces numerous changes in brain vessels and the barrier system.

  8. Complete blood count and retinal vessel calibers.

    Directory of Open Access Journals (Sweden)

    Gerald Liew

    Full Text Available OBJECTIVE: The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers. METHODS: Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992-4. Retinal arteriolar and venular calibers were measured from digitized retinal photographs using a validated semi-automated computer program. RESULTS: All analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar caliber (p = 0.02, 0.03 and 0.001 respectively, while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular caliber (p<0.0001 for all. Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1-2 µm wider venular caliber. CONCLUSIONS: These associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.

  9. Immersive volume rendering of blood vessels

    Science.gov (United States)

    Long, Gregory; Kim, Han Suk; Marsden, Alison; Bazilevs, Yuri; Schulze, Jürgen P.

    2012-03-01

    In this paper, we present a novel method of visualizing flow in blood vessels. Our approach reads unstructured tetrahedral data, resamples it, and uses slice based 3D texture volume rendering. Due to the sparse structure of blood vessels, we utilize an octree to efficiently store the resampled data by discarding empty regions of the volume. We use animation to convey time series data, wireframe surface to give structure, and utilize the StarCAVE, a 3D virtual reality environment, to add a fully immersive element to the visualization. Our tool has great value in interdisciplinary work, helping scientists collaborate with clinicians, by improving the understanding of blood flow simulations. Full immersion in the flow field allows for a more intuitive understanding of the flow phenomena, and can be a great help to medical experts for treatment planning.

  10. Zinc oxide nanoflowers make new blood vessels

    Science.gov (United States)

    Barui, Ayan Kumar; Veeriah, Vimal; Mukherjee, Sudip; Manna, Joydeb; Patel, Ajay Kumar; Patra, Sujata; Pal, Krishnendu; Murali, Shruthi; Rana, Rohit K.; Chatterjee, Suvro; Patra, Chitta Ranjan

    2012-11-01

    It is well established that angiogenesis is the process of formation of new capillaries from pre-existing blood vessels. It is a complex process, involving both pro- and anti-angiogenic factors, and plays a significant role in physiological and pathophysiological processes such as embryonic development, atherosclerosis, post-ischemic vascularization of the myocardium, tumor growth and metastasis, rheumatoid arthritis etc. This is the first report of zinc oxide (ZnO) nanoflowers that show significant pro-angiogenic properties (formation of new capillaries from pre-existing blood vessels), observed by in vitro and in vivo angiogenesis assays. The egg yolk angiogenesis assay using ZnO nanoflowers indicates the presence of matured blood vessels formation. Additionally, it helps to promote endothelial cell (EA.hy926 cells) migration in wound healing assays. Formation of reactive oxygen species (ROS), especially hydrogen peroxide (H2O2)--a redox signaling molecule, might be the plausible mechanism for nanoflower-based angiogenesis. Angiogenesis by nanoflowers may provide the basis for the future development of new alternative therapeutic treatment strategies for cardiovascular and ischemic diseases, where angiogenesis plays a significant role.It is well established that angiogenesis is the process of formation of new capillaries from pre-existing blood vessels. It is a complex process, involving both pro- and anti-angiogenic factors, and plays a significant role in physiological and pathophysiological processes such as embryonic development, atherosclerosis, post-ischemic vascularization of the myocardium, tumor growth and metastasis, rheumatoid arthritis etc. This is the first report of zinc oxide (ZnO) nanoflowers that show significant pro-angiogenic properties (formation of new capillaries from pre-existing blood vessels), observed by in vitro and in vivo angiogenesis assays. The egg yolk angiogenesis assay using ZnO nanoflowers indicates the presence of matured blood

  11. Designer blood vessels and therapeutic revascularization

    OpenAIRE

    Berglund, Joseph D; Galis, Zorina S.

    2003-01-01

    Inadequate vascular perfusion leads to fatal heart attacks, chronic ulcers, and other serious clinical conditions. The body's capacity to restore vascular perfusion through angiogenesis and arteriogenesis is often impaired by pre-existing disease, and availability of native replacements for nonfunctional arteries is limited in many patients. Thus, recreating blood vessels of various calibres through novel engineering technologies has emerged as a radical option among therapeutic strategies fo...

  12. Noninvasive blood pressure measurement in large vessels

    International Nuclear Information System (INIS)

    Pulse pressure in the aorta was evaluated by the measurement of pulse wave velocity (PWV) and blood flow velocity (BFV). PWV reflects the elasticity of the vessel and was determined by a time-of-flight method. BFV was measured by analyzing the change of magnetization decay due to flow in multiecho experiments. If one neglects pulse wave reflections at vascular branch points and flow resistance due to blood viscosity, pulse pressure is proportional to PWV and BFV. Noninvasive MR imaging measurements were obtained in 12 patients, all of whom underwent correlative arterial catheterization. Values varied between 35 and 100 mm Hg. The results demonstrated a high correlation between the two methods

  13. Photoacoustic removal of occlusions from blood vessels

    Science.gov (United States)

    Visuri, Steven R.; Da Silva, Luiz B.; Celliers, Peter M.; London, Richard A.; Maitland, IV, Duncan J.; Esch, Victor C.

    2002-01-01

    Partial or total occlusions of fluid passages within the human body are removed by positioning an array of optical fibers in the passage and directing treatment radiation pulses along the fibers, one at a time, to generate a shock wave and hydrodynamics flows that strike and emulsify the occlusions. A preferred application is the removal of blood clots (thrombin and embolic) from small cerebral vessels to reverse the effects of an ischemic stroke. The operating parameters and techniques are chosen to minimize the amount of heating of the fragile cerebral vessel walls occurring during this photo acoustic treatment. One such technique is the optical monitoring of the existence of hydrodynamics flow generating vapor bubbles when they are expected to occur and stopping the heat generating pulses propagated along an optical fiber that is not generating such bubbles.

  14. [Nitroxidergic nerve fibers of intracerabral blood vessels].

    Science.gov (United States)

    Kotsiuba, A E; Kotsiuba, E P; Chertok, V M

    2009-01-01

    Methods of light and electron microscopic histochemistry were applied to study the structure and distribution of NADPH-diaphorase-positive neurons and processes in the parietal area of rat cerebral cortex. It was found that the most of the neurons displayed close connections with the intracerebral vessels. In the cerebral cortex, the smallest distance between the axonal plasma membrane and smooth muscle cells of the intracerebral arteries was found to be no less than 0.3-0.5 microm. Neuronal cell bodies were located in the functionally important areas of the vessels (in the areas of lateral trunk branching and in arteriolar sources), while their processes accompanied the vessels, tightly embracing them with their branches. Quite often, the neurons, the dendrites of which make contacts with the bodies or processes of over- or underlying neurons, sent their nerve fibers to the arteries, veins and capillaries. Thus, nitroxidergic neurons or their groups may control the blood flow in the different areas of vascular bed, performing the functions of the local nerve center.

  15. Application of Computational Physics: Blood Vessel Constrictions and Medical Infuses

    CERN Document Server

    Suprijadi,; Subekti, Petrus; Viridi, Sparisoma

    2013-01-01

    Application of computation in many fields are growing fast in last two decades. Increasing on computation performance helps researchers to understand natural phenomena in many fields of science and technology including in life sciences. Computational fluid dynamic is one of numerical methods which is very popular used to describe those phenomena. In this paper we propose moving particle semi-implicit (MPS) and molecular dynamics (MD) to describe different phenomena in blood vessel. The effect of increasing the blood pressure on vessel wall will be calculate using MD methods, while the two fluid blending dynamics will be discussed using MPS. Result from the first phenomenon shows that around 80% of constriction on blood vessel make blood vessel increase and will start to leak on vessel wall, while from the second phenomenon the result shows the visualization of two fluids mixture (drugs and blood) influenced by ratio of drugs debit to blood debit. Keywords: molecular dynamic, blood vessel, fluid dynamic, movin...

  16. Morphogenetic mechanisms of blood vessel fusion in the Zebrafish embryo

    OpenAIRE

    Herwig, Lukas Walter

    2012-01-01

    The formation of a vascular network requires the connection and formation of a lumen between individual endothelial sprouts, a process called vessel fusion or anastomosis. In the vertebrate trunk of the zebrafish (Danio rerio), the intersegmental vessels (ISVs) develop by angiogenesis, i.e. the formation of new vessels by pre-existing vessels, in a conserved metameric manner, which allows the analysis of morphogenetic mechanisms of blood vessel development. From the dorsal aorta (DA) individu...

  17. Avian Blood-Vessel Formation in Space

    Science.gov (United States)

    Lelkes, Peter I.

    1999-01-01

    Based on previous studies, we hypothesized that the developmental anomalies observed in the past might be related to or caused by delayed or improper vascular development. The objective of our research is to test the hypothesis that exposure to microgravity during space flight cause delayed or improper vascular development during embryogenesis. The effects of microgravity on the time course and extent of avian blood-vessel formation are assessed using two models, one for angiogenesis and one for vasculogenesis. The methodological approach is dictated by the constraints of the tissue preservation method used in space. Thus, both in the chorioallantoic membrane (CAM) and in the adrenal, we will evaluate microscopically the vascular architecture and immunostain endothelial cells with specific antibodies (anti- vWF and QH1). The extent of ECM protein deposition will be assessed by immunohistochemistry and correlated with the degree of vascularization, using computer-based image analysis. Also, the cellular source for ECM proteins will be assessed by in situ hybridization.

  18. Silk fibroin microtubes for blood vessel engineering.

    Science.gov (United States)

    Lovett, Michael; Cannizzaro, Christopher; Daheron, Laurence; Messmer, Brady; Vunjak-Novakovic, Gordana; Kaplan, David L

    2007-12-01

    Currently available synthetic grafts demonstrate moderate success at the macrovascular level, but fail at the microvascular scale (inner diameter). We report on the development of silk fibroin microtubes for blood vessel repair with several advantages over existing scaffold materials/designs. These microtubes were prepared by dipping straight lengths of stainless steel wire into aqueous silk fibroin, where the addition of poly(ethylene oxide) (PEO) enabled control of microtube porosity. The microtube properties were characterized in terms of pore size, burst strength, protein permeability, enzymatic degradation, and cell migration. Low porosity microtubes demonstrated superior mechanical properties in terms of higher burst pressures, but displayed poor protein permeability; whereas higher porosity tubes had lower burst strengths but increased permeability and enhanced protein transport. The microtubes also exhibited cellular barrier functions as low porosity tubes prevented outward migration of GFP-transduced HUVECs, while the high porosity microtubes allowed a few cells per tube to migrate outward during perfusion. When combined with the biocompatible and suturability features of silk fibroin, these results suggest that silk microtubes, either implanted directly or preseeded with cells, are an attractive biomaterial for microvascular grafts. PMID:17727944

  19. Tumour angiogenesis-Origin of blood vessels.

    Science.gov (United States)

    Krishna Priya, S; Nagare, R P; Sneha, V S; Sidhanth, C; Bindhya, S; Manasa, P; Ganesan, T S

    2016-08-15

    The conventional view of tumour vascularization is that tumours acquire their blood supply from neighbouring normal stroma. Additional methods of tumour vascularization such as intussusceptive angiogenesis, vasculogenic mimicry, vessel co-option and vasculogenesis have been demonstrated to occur. However, the origin of the endothelial cells and pericytes in the tumour vasculature is not fully understood. Their origin from malignant cells has been shown indirectly in lymphoma and neuroblastoma by immuno-FISH experiments. It is now evident that tumours arise from a small population of cells called cancer stem cells (CSCs) or tumour initiating cells. Recent data suggest that a proportion of tumour endothelial cells arise from cancer stem cells in glioblastoma. This was demonstrated both in vitro and in vivo. The analysis of chromosomal abnormalities in endothelial cells showed identical genetic changes to those identified in tumour cells. However, another report contradicted these results from the earlier studies in glioblastoma and had shown that CSCs give rise to pericytes and not endothelial cells. The main thrust of this review is the critical analysis of the conflicting data from different studies and the remaining questions in this field of research. The mechanism by which this phenomenon occurs is also discussed in detail. The transdifferentiation of CSCs to endothelial cells/pericytes has many implications in the progression and metastasis of the tumours and hence it would be a novel target for antiangiogenic therapy. PMID:26934471

  20. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit;

    2006-01-01

    and blood glucose, variations in retinal blood vessel diameters and blood pressure were predominantly attributable to genetic effects. A genetic influence may have a role in individual susceptibility to hypertension and other vascular diseases. The results suggest that retinal vessel diameters......PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...

  1. 2011 Pleasure Craft Sailing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  2. 2013 Pleasure Craft and Sailing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  3. 2013 Tug and Towing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  4. Detection and measurement of retinal blood vessel pulsatile motion

    Science.gov (United States)

    Xiao, Di; Frost, Shaun; Vignarajan, Janardhan; An, Dong; Tay-Kearney, Mei-Ling; Kanagasingam, Yogi

    2016-03-01

    Retinal photography is a non-invasive and well-accepted clinical diagnosis of ocular diseases. Qualitative and quantitative assessment of retinal images is crucial in ocular diseases related clinical application. Pulsatile properties caused by cardiac rhythm, such as spontaneous venous pulsation (SVP) and pulsatile motion of small arterioles, can be visualized by dynamic retinal imaging techniques and provide clinical significance. In this paper, we aim at vessel pulsatile motion detection and measurement. We proposed a novel approach for pulsatile motion measurement of retinal blood vessels by applying retinal image registration, blood vessel detection and blood vessel motion detection and measurement on infrared retinal image sequences. The performance of the proposed methods was evaluated on 8 image sequences with 240 images. A preliminary result has demonstrated the good performance of the method for blood vessel pulsatile motion observation and measurement.

  5. Lymphatic vessel density and function in experimental bladder cancer

    International Nuclear Information System (INIS)

    The lymphatics form a second circulatory system that drains the extracellular fluid and proteins from the tumor microenvironment, and provides an exclusive environment in which immune cells interact and respond to foreign antigen. Both cancer and inflammation are known to induce lymphangiogenesis. However, little is known about bladder lymphatic vessels and their involvement in cancer formation and progression. A double transgenic mouse model was generated by crossing a bladder cancer-induced transgenic, in which SV40 large T antigen was under the control of uroplakin II promoter, with another transgenic mouse harboring a lacZ reporter gene under the control of an NF-κB-responsive promoter (κB-lacZ) exhibiting constitutive activity of β-galactosidase in lymphatic endothelial cells. In this new mouse model (SV40-lacZ), we examined the lymphatic vessel density (LVD) and function (LVF) during bladder cancer progression. LVD was performed in bladder whole mounts and cross-sections by fluorescent immunohistochemistry (IHC) using LYVE-1 antibody. LVF was assessed by real-time in vivo imaging techniques using a contrast agent (biotin-BSA-Gd-DTPA-Cy5.5; Gd-Cy5.5) suitable for both magnetic resonance imaging (MRI) and near infrared fluorescence (NIRF). In addition, IHC of Cy5.5 was used for time-course analysis of co-localization of Gd-Cy5.5 with LYVE-1-positive lymphatics and CD31-positive blood vessels. SV40-lacZ mice develop bladder cancer and permitted visualization of lymphatics. A significant increase in LVD was found concomitantly with bladder cancer progression. Double labeling of the bladder cross-sections with LYVE-1 and Ki-67 antibodies indicated cancer-induced lymphangiogenesis. MRI detected mouse bladder cancer, as early as 4 months, and permitted to follow tumor sizes during cancer progression. Using Gd-Cy5.5 as a contrast agent for MRI-guided lymphangiography, we determined a possible reduction of lymphatic flow within the tumoral area. In addition, NIRF

  6. Instability and `Sausage-String' Appearance in Blood Vessels during High Blood Pressure

    OpenAIRE

    Alstrøm, P.; Eguíluz, Víctor M.; Holstein-Rathlou, Niels-Henrik

    1998-01-01

    A new Rayleigh-type instability is proposed to explain the `sausage-string' pattern of alternating constrictions and dilatations formed in blood vessels under influence of a vasoconstricting agent. Our theory involves the nonlinear elasticity characteristics of the vessel wall, and provides predictions for the conditions under which the cylindrical form of a blood vessel becomes unstable.

  7. Instability and "Sausage-String" Appearance in Blood Vessels during High Blood Pressure

    CERN Document Server

    Alstrøm, P; Colding-Jorgensen, M; Gustafsson, F; Holstein-Rathlou, N H; Alstrom, Preben; Eguiluz, Victor M.; Colding-Jorgensen, Morten; Gustafsson, Finn; Holstein-Rathlou, Niels-Henrik

    1999-01-01

    A new Rayleigh-type instability is proposed to explain the `sausage-string' pattern of alternating constrictions and dilatations formed in blood vessels under influence of a vasoconstricting agent. Our theory involves the nonlinear elasticity characteristics of the vessel wall, and provides predictions for the conditions under which the cylindrical form of a blood vessel becomes unstable.

  8. Lattice BGK Simulations of the Blood Flow in Elastic Vessels

    Institute of Scientific and Technical Information of China (English)

    LU Xiao-Yang; YI Hou-Hui; CHEN Ji-Yao; FANG Hai-Ping

    2006-01-01

    @@ The lattice Boltzmann method is applied to study the flow in elastic blood vessels. The volume-flow rate increases considerably when the compliance constant of the blood vessel is below a critical value. There is a region of the compliance constant in which the average volume-flow rate is dramatically enhanced. A harmonic perturbation of the pressure does not change the behaviour of the average volume-flow rate while the harmonic wave attenuates very quickly along the tube when the resonant period is close to that of the input wave. The model, together with the simulation results, is expected to be helpful to understand the mechanism of the blood volume-flow rate related to the compliance constant of the blood vessel, especially on the dependence of the flux of human blood vessel under weather changes, which has medical significance.

  9. Distinct bone marrow blood vessels differentially regulate haematopoiesis.

    Science.gov (United States)

    Itkin, Tomer; Gur-Cohen, Shiri; Spencer, Joel A; Schajnovitz, Amir; Ramasamy, Saravana K; Kusumbe, Anjali P; Ledergor, Guy; Jung, Yookyung; Milo, Idan; Poulos, Michael G; Kalinkovich, Alexander; Ludin, Aya; Kollet, Orit; Shakhar, Guy; Butler, Jason M; Rafii, Shahin; Adams, Ralf H; Scadden, David T; Lin, Charles P; Lapidot, Tsvee

    2016-04-21

    Bone marrow endothelial cells (BMECs) form a network of blood vessels that regulate both leukocyte trafficking and haematopoietic stem and progenitor cell (HSPC) maintenance. However, it is not clear how BMECs balance these dual roles, and whether these events occur at the same vascular site. We found that mammalian bone marrow stem cell maintenance and leukocyte trafficking are regulated by distinct blood vessel types with different permeability properties. Less permeable arterial blood vessels maintain haematopoietic stem cells in a low reactive oxygen species (ROS) state, whereas the more permeable sinusoids promote HSPC activation and are the exclusive site for immature and mature leukocyte trafficking to and from the bone marrow. A functional consequence of high permeability of blood vessels is that exposure to blood plasma increases bone marrow HSPC ROS levels, augmenting their migration and differentiation, while compromising their long-term repopulation and survival. These findings may have relevance for clinical haematopoietic stem cell transplantation and mobilization protocols. PMID:27074509

  10. A functional requirement for astroglia in promoting blood vessel development in the early postnatal brain.

    Directory of Open Access Journals (Sweden)

    Shang Ma

    Full Text Available Astroglia are a major cell type in the brain and play a key role in many aspects of brain development and function. In the adult brain, astrocytes are known to intimately ensheath blood vessels and actively coordinate local neural activity and blood flow. During development of the neural retina, blood vessel growth follows a meshwork of astrocytic processes. Several genes have also been implicated in retinal astrocytes for regulating vessel development. This suggests a role of astrocytes in promoting angiogenesis throughout the central nervous system. To determine the roles that astrocytes may play during brain angiogenesis, we employ genetic approaches to inhibit astrogliogenesis during perinatal corticogenesis and examine its effects on brain vessel development. We find that conditional deletion from glial progenitors of orc3, a gene required for DNA replication, dramatically reduces glial progenitor cell number in the subventricular zone and astrocytes in the early postnatal cerebral cortex. This, in turn, results in severe reductions in both the density and branching frequency of cortical blood vessels. Consistent with a delayed growth but not regression of vessels, we find neither significant net decreases in vessel density between different stages after normalizing for cortical expansion nor obvious apoptosis of endothelial cells in these mutants. Furthermore, concomitant with loss of astroglial interactions, we find increased endothelial cell proliferation, enlarged vessel luminal size as well as enhanced cytoskeletal gene expression in pericytes, which suggests compensatory changes in vascular cells. Lastly, we find that blood vessel morphology in mutant cortices recovers substantially at later stages, following astrogliosis. These results thus implicate a functional requirement for astroglia in promoting blood vessel growth during brain development.

  11. Automated blood vessel extraction using local features on retinal images

    Science.gov (United States)

    Hatanaka, Yuji; Samo, Kazuki; Tajima, Mikiya; Ogohara, Kazunori; Muramatsu, Chisako; Okumura, Susumu; Fujita, Hiroshi

    2016-03-01

    An automated blood vessel extraction using high-order local autocorrelation (HLAC) on retinal images is presented. Although many blood vessel extraction methods based on contrast have been proposed, a technique based on the relation of neighbor pixels has not been published. HLAC features are shift-invariant; therefore, we applied HLAC features to retinal images. However, HLAC features are weak to turned image, thus a method was improved by the addition of HLAC features to a polar transformed image. The blood vessels were classified using an artificial neural network (ANN) with HLAC features using 105 mask patterns as input. To improve performance, the second ANN (ANN2) was constructed by using the green component of the color retinal image and the four output values of ANN, Gabor filter, double-ring filter and black-top-hat transformation. The retinal images used in this study were obtained from the "Digital Retinal Images for Vessel Extraction" (DRIVE) database. The ANN using HLAC output apparent white values in the blood vessel regions and could also extract blood vessels with low contrast. The outputs were evaluated using the area under the curve (AUC) based on receiver operating characteristics (ROC) analysis. The AUC of ANN2 was 0.960 as a result of our study. The result can be used for the quantitative analysis of the blood vessels.

  12. Preventing pathological regression of blood vessels

    OpenAIRE

    Keshet, Eli

    2003-01-01

    Oxygen administration to premature infants suppresses retinal VEGF expression and results in the catastrophic vessel loss associated with retinopathy of prematurity. A study investigating the development of the retinal vasculature in mice (see related article on pages 50–57) demonstrates that specific activation of VEGF receptor-1 by placental growth factor-1 protects against oxygen-induced vessel loss without stimulating vascular proliferation and neovascularization.

  13. A Computational Model Predicting Disruption of Blood Vessel Development

    Science.gov (United States)

    Vascular development is a complex process regulated by dynamic biological networks that vary in topology and state across different tissues and developmental stages. Signals regulating de novo blood vessel formation (vasculogenesis) and remodeling (angiogenesis) come from a varie...

  14. Blood flow changes coincide with cellular rearrangements during blood vessel pruning in zebrafish embryos.

    Directory of Open Access Journals (Sweden)

    Eva Kochhan

    Full Text Available After the initial formation of a highly branched vascular plexus, blood vessel pruning generates a hierarchically structured network with improved flow characteristics. We report here on the cellular events that occur during the pruning of a defined blood vessel in the eye of developing zebrafish embryos. Time-lapse imaging reveals that the connection of a new blood vessel sprout with a previously perfused multicellular endothelial tube leads to the formation of a branched, Y-shaped structure. Subsequently, endothelial cells in parts of the previously perfused branch rearrange from a multicellular into a unicellular tube, followed by blood vessel detachment. This process is accompanied by endothelial cell death. Finally, we show that differences in blood flow between neighboring vessels are important for the completion of the pruning process. Our data suggest that flow induced changes in tubular architecture ensure proper blood vessel pruning.

  15. Development of a blood vessel searching device for HMS

    Science.gov (United States)

    Kuroda, Tatsuro; Uenoya, Toshiyuki; Tsuchiya, Kazuyoshi; Uetsuji, Yasutomo; Nakamachi, Eiji

    2007-12-01

    In this study, an automatic blood vessel searching system (BVSS) is newly developed, which is built in the health monitoring system (HMS) and the drug delivery system (DDS) to extract the blood, evaluates the blood sugar level and injects the insulin for the diabetic patients. Main subjects of our BVSS development are 1) a transmittance photo imaging of the finger by using the LED light as a near-infrared light source with peak wave length of 870 nm, and 2) an image processing to detect the location of the center of the blood vessel cross section. The sharp edge focus method was applied in our BVSS to detect the depth of blood vessel. We carried out experiments by using blood vessel phantoms, which consist of an artificial cylindrical blood vessel and skin tissue, which are made of the teflon tube and the silicone rubber. The teflon tube has the size of 0.6 mm in diameter and is filled with the human blood. The experimental results demonstrated that the estimated depth, which is obtained by image analysis corresponding to given depths, shows a good agreement with the real values, and consequently the availability of our BVSS is confirmed.

  16. Diffuse light tomography to detect blood vessels using Tikhonov regularization

    Science.gov (United States)

    Kazanci, Huseyin O.; Jacques, Steven L.

    2016-04-01

    Detection of blood vessels within light-scattering tissues involves detection of subtle shadows as blood absorbs light. These shadows are diffuse but measurable by a set of source-detector pairs in a spatial array of sources and detectors on the tissue surface. The measured shadows can reconstruct the internal position(s) of blood vessels. The tomographic method involves a set of Ns sources and Nd detectors such that Nsd = Ns x Nd source-detector pairs produce Nsd measurements, each interrogating the tissue with a unique perspective, i.e., a unique region of sensitivity to voxels within the tissue. This tutorial report describes the reconstruction of the image of a blood vessel within a soft tissue based on such source-detector measurements, by solving a matrix equation using Tikhonov regularization. This is not a novel contribution, but rather a simple introduction to a well-known method, demonstrating its use in mapping blood perfusion.

  17. DETECTION OF BLOOD VESSELS AND MEASUREMENT OF VESSEL WIDTH FOR DIABETIC RETINOPATHY

    Directory of Open Access Journals (Sweden)

    S.Sukanya

    2014-09-01

    Full Text Available The proposed method measures the retinal blood vessel diameter to identify arteriolar narrowing, arteriovenous (AV nicking, branching coefficients to detect early diabetic retinopathy. It utilizes the vessel centerline and edge information to measure the width for a vessel segment. From the input retinal image, the vascular network is extracted using the local entropy thresholding method. The vessel boundaries are extracted using sobel edge detection method. The skeletonization operation is applied to the vascular network and mapping the vessel boundaries and the skeleton image. The branching point detection method is then performed to localize all crossing locations. A rotational invariant mask to search the pixel pairs from the edge image, and calculate the shortest distance pair which provides the vessel width (or diameter for that cross-section. Variation in the width measurement identifies the diabetic retinopathy.

  18. Brain blood vessel segmentation using line-shaped profiles

    Science.gov (United States)

    Babin, Danilo; Pižurica, Aleksandra; De Vylder, Jonas; Vansteenkiste, Ewout; Philips, Wilfried

    2013-11-01

    Segmentation of cerebral blood vessels is of great importance in diagnostic and clinical applications, especially for embolization of cerebral aneurysms and arteriovenous malformations (AVMs). In order to perform embolization of the AVM, the structural and geometric information of blood vessels from 3D images is of utmost importance. For this reason, the in-depth segmentation of cerebral blood vessels is usually done as a fusion of different segmentation techniques, often requiring extensive user interaction. In this paper we introduce the idea of line-shaped profiling with an application to brain blood vessel and AVM segmentation, efficient both in terms of resolving details and in terms of computation time. Our method takes into account both local proximate and wider neighbourhood of the processed pixel, which makes it efficient for segmenting large blood vessel tree structures, as well as fine structures of the AVMs. Another advantage of our method is that it requires selection of only one parameter to perform segmentation, yielding very little user interaction.

  19. OBSERVATIONS ON VASCULAR PATTERN OF CHORIONIC BLOOD VESSELS OF PLACENTA

    Directory of Open Access Journals (Sweden)

    Yousuf Sarwar

    2013-10-01

    Full Text Available ABSTRACT: BACKGROUND: Placenta is a choriodecidual structure develops during pregnancy implanted on the uterine wall and car ries vital functions. It is connected to the foetus through umbilical cord. The branches of umbilical vessels that traverse along foetal surface of placenta are referred as chorionic vessels. There are two different patterns of chorionic vessels – Dispersa l and Magistral. In the dispersal type, the umbilical vessels undergo successive divisions with gradually diminishing caliber towards periphery while in magistral pattern the vessels traverse to the edge of placenta without appreciable decrease in diameter of vessels. The present study has been done for visualization of the pattern of chorionic vessels in placenta obtained from labour room of a tertiary care hospital in eastern Bihar, India. MATERIALS AND METHODS: A total of one hundred and fifty (150 fres h and intact placenta of full term pregnancies collected from Obstetrics & Gynaecology department were included in the study. After washing with distilled water, removal of blood clots were done with slight digital pressure applied over arteries and vein a nd later on by irrigation with saline. The cut end of the umbilical cord was carefully visualized to identify the umbilical arteries and vein. Dye was injected into umbilical vessels under normal physiological pressure and diameter of chorionic blood vesse ls were taken at the center and periphery. Ultimately each vessel was followed and examined to observe the dispersal and magistral pattern of chorionic blood vessels of placenta. RESULTS AND CONCLUSION: Out of the total of one hundred and fifty (150 full term placenta obtained and examined in the Anatomy department during the study period, 64% Dispersal type & 36 % of Magistral type of arterial pattern of branching of chorionic vessels were observed. Vein and its tributaries presented Dispersal pattern in 60% and Magistral pattern in 40%. There is a significant

  20. Customizable engineered blood vessels using 3D printed inserts.

    Science.gov (United States)

    Pinnock, Cameron B; Meier, Elizabeth M; Joshi, Neeraj N; Wu, Bin; Lam, Mai T

    2016-04-15

    Current techniques for tissue engineering blood vessels are not customizable for vascular size variation and vessel wall thickness. These critical parameters vary widely between the different arteries in the human body, and the ability to engineer vessels of varying sizes could increase capabilities for disease modeling and treatment options. We present an innovative method for producing customizable, tissue engineered, self-organizing vascular constructs by replicating a major structural component of blood vessels - the smooth muscle layer, or tunica media. We utilize a unique system combining 3D printed plate inserts to control construct size and shape, and cell sheets supported by a temporary fibrin hydrogel to encourage cellular self-organization into a tubular form resembling a natural artery. To form the vascular construct, 3D printed inserts are adhered to tissue culture plates, fibrin hydrogel is deposited around the inserts, and human aortic smooth muscle cells are then seeded atop the fibrin hydrogel. The gel, aided by the innate contractile properties of the smooth muscle cells, aggregates towards the center post insert, creating a tissue ring of smooth muscle cells. These rings are then stacked into the final tubular construct. Our methodology is robust, easily repeatable and allows for customization of cellular composition, vessel wall thickness, and length of the vessel construct merely by varying the size of the 3D printed inserts. This platform has potential for facilitating more accurate modeling of vascular pathology, serving as a drug discovery tool, or for vessel repair in disease treatment. PMID:26732049

  1. Customizable engineered blood vessels using 3D printed inserts.

    Science.gov (United States)

    Pinnock, Cameron B; Meier, Elizabeth M; Joshi, Neeraj N; Wu, Bin; Lam, Mai T

    2016-04-15

    Current techniques for tissue engineering blood vessels are not customizable for vascular size variation and vessel wall thickness. These critical parameters vary widely between the different arteries in the human body, and the ability to engineer vessels of varying sizes could increase capabilities for disease modeling and treatment options. We present an innovative method for producing customizable, tissue engineered, self-organizing vascular constructs by replicating a major structural component of blood vessels - the smooth muscle layer, or tunica media. We utilize a unique system combining 3D printed plate inserts to control construct size and shape, and cell sheets supported by a temporary fibrin hydrogel to encourage cellular self-organization into a tubular form resembling a natural artery. To form the vascular construct, 3D printed inserts are adhered to tissue culture plates, fibrin hydrogel is deposited around the inserts, and human aortic smooth muscle cells are then seeded atop the fibrin hydrogel. The gel, aided by the innate contractile properties of the smooth muscle cells, aggregates towards the center post insert, creating a tissue ring of smooth muscle cells. These rings are then stacked into the final tubular construct. Our methodology is robust, easily repeatable and allows for customization of cellular composition, vessel wall thickness, and length of the vessel construct merely by varying the size of the 3D printed inserts. This platform has potential for facilitating more accurate modeling of vascular pathology, serving as a drug discovery tool, or for vessel repair in disease treatment.

  2. Purinergic signaling and blood vessels in health and disease.

    Science.gov (United States)

    Burnstock, Geoffrey; Ralevic, Vera

    2014-01-01

    Purinergic signaling plays important roles in control of vascular tone and remodeling. There is dual control of vascular tone by ATP released as a cotransmitter with noradrenaline from perivascular sympathetic nerves to cause vasoconstriction via P2X1 receptors, whereas ATP released from endothelial cells in response to changes in blood flow (producing shear stress) or hypoxia acts on P2X and P2Y receptors on endothelial cells to produce nitric oxide and endothelium-derived hyperpolarizing factor, which dilates vessels. ATP is also released from sensory-motor nerves during antidromic reflex activity to produce relaxation of some blood vessels. In this review, we stress the differences in neural and endothelial factors in purinergic control of different blood vessels. The long-term (trophic) actions of purine and pyrimidine nucleosides and nucleotides in promoting migration and proliferation of both vascular smooth muscle and endothelial cells via P1 and P2Y receptors during angiogenesis and vessel remodeling during restenosis after angioplasty are described. The pathophysiology of blood vessels and therapeutic potential of purinergic agents in diseases, including hypertension, atherosclerosis, ischemia, thrombosis and stroke, diabetes, and migraine, is discussed.

  3. Electromechanical Model of Blood Flow in Vessels

    OpenAIRE

    Ivo Cap; Barbora Czippelova

    2008-01-01

    The present paper deals with some theoretical derivations connected with very efficient method of solution of hydrodynamic problems of blood flow in human cardiovascular system. The electromechanical analogy of liquid flow in a tube and electromagnetic wave propagating along an electric transmission line is discussed. We have derived a detailed circuit-like model of an elementary section of the elastic tube with viscose Newtonian liquid. The analogy harmonic current electrical cir...

  4. FCM Based Blood Vessel Segmentation Method for Retinal Images

    Directory of Open Access Journals (Sweden)

    Nilanjan Dey

    2012-06-01

    Full Text Available Segmentation of blood vessels in retinal images providesearly diagnosis of diseases like glaucoma, diabeticretinopathy and macular degeneration. Among thesediseases occurrence of Glaucoma is most frequent and hasserious ocular consequences that can even lead toblindness, if it is not detected early. The clinical criteria forthe diagnosis of glaucoma include intraocular pressuremeasurement, optic nerve head evaluation, retinal nervefiber layer and visual field defects. This form of bloodvessel segmentation helps in early detection for ophthalmicdiseases, and potentially reduces the risk of blindness.The low-contrast images at the retina owing to narrowblood vessels of the retina are difficult to extract. Theselow contrast images are, however useful in revealingcertain systemic diseases. Motivated by the goals ofimproving detection of such vessels, this present workproposes an algorithm for segmentation of blood vessels,and compares the results between expert ophthalmologists’hand-drawn ground-truths and segmented image (i.e. theoutput of the present work. Sensitivity, specificity, positivepredictive value (PPV, positive likelihood ratio (PLR andaccuracy are used to evaluate overall performance. It isfound that this work segments blood vessels successfullywith sensitivity, specificity, PPV, PLR and accuracy of99.62%, 54.66%, 95.08%, 219.72 and 95.03%,respectively.

  5. Retinal Blood Vessel Segmentation with Optic Disc Pixels Exclusion

    Directory of Open Access Journals (Sweden)

    Randy Cahya Wihandika

    2013-06-01

    Full Text Available The morphological changes of retinal blood vessels are important indicators used to diagnose and monitor the progression of various diseases. A number of retinal blood vessel segmentation methods have been introduced, including the line operator based methods, which have shown satisfactory results. However, the basic line operator method cannot discriminate the pixels around the retinal optic disc, resulting in false classification of those pixels. In this paper, we integrate the detection of pixels around the retinal optic disc to the line operator method so that those pixels can be excluded from the vessel pixels. The method is evaluated on the widely used retinal dataset, the DRIVE dataset. The results demonstrate that the proposed method has made improvements over the basic and the multi-scale line detector with accuracy and area under curve of 0.942 and 0.9521, respectively.

  6. Gene expression analysis in human breast cancer associated blood vessels.

    Directory of Open Access Journals (Sweden)

    Dylan T Jones

    Full Text Available Angiogenesis is essential for solid tumour growth, whilst the molecular profiles of tumour blood vessels have been reported to be different between cancer types. Although presently available anti-angiogenic strategies are providing some promise for the treatment of some cancers it is perhaps not surprisingly that, none of the anti-angiogenic agents available work on all tumours. Thus, the discovery of novel anti-angiogenic targets, relevant to individual cancer types, is required. Using Affymetrix microarray analysis of laser-captured, CD31-positive blood vessels we have identified 63 genes that are upregulated significantly (5-72 fold in angiogenic blood vessels associated with human invasive ductal carcinoma (IDC of the breast as compared with blood vessels in normal human breast. We tested the angiogenic capacity of a subset of these genes. Genes were selected based on either their known cellular functions, their enriched expression in endothelial cells and/or their sensitivity to anti-VEGF treatment; all features implicating their involvement in angiogenesis. For example, RRM2, a ribonucleotide reductase involved in DNA synthesis, was upregulated 32-fold in IDC-associated blood vessels; ATF1, a nuclear activating transcription factor involved in cellular growth and survival was upregulated 23-fold in IDC-associated blood vessels and HEX-B, a hexosaminidase involved in the breakdown of GM2 gangliosides, was upregulated 8-fold in IDC-associated blood vessels. Furthermore, in silico analysis confirmed that AFT1 and HEX-B also were enriched in endothelial cells when compared with non-endothelial cells. None of these genes have been reported previously to be involved in neovascularisation. However, our data establish that siRNA depletion of Rrm2, Atf1 or Hex-B had significant anti-angiogenic effects in VEGF-stimulated ex vivo mouse aortic ring assays. Overall, our results provide proof-of-principle that our approach can identify a cohort of

  7. Comparison of the Blood and Lymphatic Microvessel Density of Pleomorphic Adenoma and Basal Cell Adenoma

    OpenAIRE

    Andresa Borges Soares; Albina Altemani; Thais Ribeiro de Oliveira; Felipe de Oliveira Fonseca Rodrigues; Alfredo Ribeiro-Silva; Danilo Figueiredo Soave; Fabricio Passador-Santos; Suellen Trentin Brum; Marcelo Henrique Napimoga; Vera Cavalcanti de Araújo

    2015-01-01

    BACKGROUND Pleomorphic adenoma (PA) is the most common tumor of the salivary gland, while basal cell adenoma (BCA) is an uncommon neoplasm. Blood and lymphatic vessels are crucial for tumor metabolism. The aim of this study was to compare the blood and lymphatic vascular density and vascular and endothelial growth factor (VEGF) expression in PA and BCA tumors. In addition, cell proliferation was evaluated in these tumors. METHODS Blood and lymphatic vessel content, VEGF expression, and cell p...

  8. Blood Vessel-Derived Acellular Matrix for Vascular Graft Application

    Directory of Open Access Journals (Sweden)

    Luigi Dall’Olmo

    2014-01-01

    Full Text Available To overcome the issues connected to the use of autologous vascular grafts and artificial materials for reconstruction of small diameter (<6 mm blood vessels, this study aimed to develop acellular matrix- (AM- based vascular grafts. Rat iliac arteries were decellularized by a detergent-enzymatic treatment, whereas endothelial cells (ECs were obtained through enzymatic digestion of rat skin followed by immunomagnetic separation of CD31-positive cells. Sixteen female Lewis rats (8 weeks old received only AM or previously in vitro reendothelialized AM as abdominal aorta interposition grafts (about 1 cm. The detergent-enzymatic treatment completely removed the cellular part of vessels and both MHC class I and class II antigens. One month after surgery, the luminal surface of implanted AMs was partially covered by ECs and several platelets adhered in the areas lacking cell coverage. Intimal hyperplasia, already detected after 1 month, increased at 3 months. On the contrary, all grafts composed by AM and ECs were completely covered at 1 month and their structure was similar to that of native vessels at 3 months. Taken together, our findings show that prostheses composed of AM preseeded with ECs could be a promising approach for the replacement of blood vessels.

  9. Investigation on artificial blood vessels prepared from bacterial cellulose

    International Nuclear Information System (INIS)

    BC (bacterial cellulose) exhibits quite distinctive properties than plant cellulose. The outstanding properties make BC a promising material for preparation of artificial blood vessel. By taking advantage of the high oxygen permeability of PDMS (polydimethylsiloxane) as a tubular template material, a series of BC tubes with a length of 100 mm, a thickness of 1 mm and an outer diameter of 4 or 6 mm were biosynthesized with the help of Gluconacetobacter xylinum. Through characterization by SEM (scanning electron microscope), tensile testing and thermal analysis, it is demonstrated that BC tubes are good enough for artificial blood vessel with elaborated nano-fiber architecture, qualified mechanical properties and high thermal stability. In addition, measurement of biocompatibility also shows that BC tubes are greatly adaptable to the in vivo environment. The results indicate that BC tubes have great potential for being utilized as tubular scaffold materials in the field of tissue engineering. - Highlights: • Bacterial cellulose (BC) can be made into tubular shape through PDMS mold. • BC represents a fine nanofiber network. • The mechanical and thermal properties of BC mimic the situation of real vessel. • BC exhibits attractive biocompatible properties as a substitution of vessel

  10. Investigation on artificial blood vessels prepared from bacterial cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Zang, Shanshan; Zhang, Ran; Chen, Hua; Lu, Yudong; Zhou, Jianhai [Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); Chang, Xiao; Qiu, Guixing; Wu, Zhihong [Department of Orthopaedics, Peking Union Medical College Hospital, Beijing 100730 (China); Yang, Guang, E-mail: yang_sunny@yahoo.com [Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2015-01-01

    BC (bacterial cellulose) exhibits quite distinctive properties than plant cellulose. The outstanding properties make BC a promising material for preparation of artificial blood vessel. By taking advantage of the high oxygen permeability of PDMS (polydimethylsiloxane) as a tubular template material, a series of BC tubes with a length of 100 mm, a thickness of 1 mm and an outer diameter of 4 or 6 mm were biosynthesized with the help of Gluconacetobacter xylinum. Through characterization by SEM (scanning electron microscope), tensile testing and thermal analysis, it is demonstrated that BC tubes are good enough for artificial blood vessel with elaborated nano-fiber architecture, qualified mechanical properties and high thermal stability. In addition, measurement of biocompatibility also shows that BC tubes are greatly adaptable to the in vivo environment. The results indicate that BC tubes have great potential for being utilized as tubular scaffold materials in the field of tissue engineering. - Highlights: • Bacterial cellulose (BC) can be made into tubular shape through PDMS mold. • BC represents a fine nanofiber network. • The mechanical and thermal properties of BC mimic the situation of real vessel. • BC exhibits attractive biocompatible properties as a substitution of vessel.

  11. Pericyte coverage of abnormal blood vessels in myelofibrotic bone marrows

    DEFF Research Database (Denmark)

    Zetterberg, Eva; Vannucchi, Alessandro M; Migliaccio, Anna Rita;

    2007-01-01

    patients with myelofibrosis differed from that in samples from controls. DESIGN AND METHODS: We assessed the microvascular density (MVD), vessel morphology and pericyte coverage in bone marrows from 19 myelofibrosis patients and nine controls. We also studied the same parameters in two mouse models...... of myelofibrosis, with genetic alterations affecting megakaryocyte differentiation (i.e. one model with low GATA-1 expression and the other with over-expression of thrombopoietin). RESULTS: In myelofibrotic marrows, MVD was 3.8-fold greater than in controls (pvessels displayed 5.9-fold larger mean...... perimeters (pvessels in patients with myelofibrosis were pericyte-coated but only 51+/-20 % of vessels in controls (p

  12. Investigation on artificial blood vessels prepared from bacterial cellulose.

    Science.gov (United States)

    Zang, Shanshan; Zhang, Ran; Chen, Hua; Lu, Yudong; Zhou, Jianhai; Chang, Xiao; Qiu, Guixing; Wu, Zhihong; Yang, Guang

    2015-01-01

    BC (bacterial cellulose) exhibits quite distinctive properties than plant cellulose. The outstanding properties make BC a promising material for preparation of artificial blood vessel. By taking advantage of the high oxygen permeability of PDMS (polydimethylsiloxane) as a tubular template material, a series of BC tubes with a length of 100 mm, a thickness of 1mm and an outer diameter of 4 or 6mm were biosynthesized with the help of Gluconacetobacter xylinum. Through characterization by SEM (scanning electron microscope), tensile testing and thermal analysis, it is demonstrated that BC tubes are good enough for artificial blood vessel with elaborated nano-fiber architecture, qualified mechanical properties and high thermal stability. In addition, measurement of biocompatibility also shows that BC tubes are greatly adaptable to the in vivo environment. The results indicate that BC tubes have great potential for being utilized as tubular scaffold materials in the field of tissue engineering.

  13. Investigation on artificial blood vessels prepared from bacterial cellulose.

    Science.gov (United States)

    Zang, Shanshan; Zhang, Ran; Chen, Hua; Lu, Yudong; Zhou, Jianhai; Chang, Xiao; Qiu, Guixing; Wu, Zhihong; Yang, Guang

    2015-01-01

    BC (bacterial cellulose) exhibits quite distinctive properties than plant cellulose. The outstanding properties make BC a promising material for preparation of artificial blood vessel. By taking advantage of the high oxygen permeability of PDMS (polydimethylsiloxane) as a tubular template material, a series of BC tubes with a length of 100 mm, a thickness of 1mm and an outer diameter of 4 or 6mm were biosynthesized with the help of Gluconacetobacter xylinum. Through characterization by SEM (scanning electron microscope), tensile testing and thermal analysis, it is demonstrated that BC tubes are good enough for artificial blood vessel with elaborated nano-fiber architecture, qualified mechanical properties and high thermal stability. In addition, measurement of biocompatibility also shows that BC tubes are greatly adaptable to the in vivo environment. The results indicate that BC tubes have great potential for being utilized as tubular scaffold materials in the field of tissue engineering. PMID:25491966

  14. Stem and progenitor cells in biostructure of blood vessel walls

    Directory of Open Access Journals (Sweden)

    Krzysztof Korta

    2013-09-01

    Full Text Available Development of vascular and hematopoietic systems during organogenesis occurs at the same time. During vasculogenesis, a small part of cells does not undergo complete differentiation but stays on this level, “anchored” in tissue structures described as stem cell niches. The presence of blood vessels within tissue stem cell niches is typical and led to identification of niches and ensures that they are functioning. The three-layer biostructure of vessel walls for artery and vein, tunica: intima, media and adventitia, for a long time was defined as a mechanical barrier between vessel light and the local tissue environment. Recent findings from vascular biology studies indicate that vessel walls are dynamic biostructures, which are equipped with stem and progenitor cells, described as vascular wall-resident stem cells/progenitor cells (VW-SC/PC. Distinct zones for vessel wall harbor heterogeneous subpopulations of VW-SC/PC, which are described as “subendothelial or vasculogenic zones”. Recent evidence from in vitro and in vivo studies show that prenatal activity of stem and progenitor cells is not only limited to organogenesis but also exists in postnatal life, where it is responsible for vessel wall homeostasis, remodeling and regeneration. It is believed that VW-SC/PC could be engaged in progression of vascular disorders and development of neointima. We would like to summarize current knowledge about mesenchymal and progenitor stem cell phenotype with special attention to distribution and biological properties of VW-SC/PC in biostructures of intima, media and adventitia niches. It is postulated that in the near future, niches for VW-SC/PC could be a good source of stem and progenitor cells, especially in the context of vessel tissue bioengineering as a new alternative to traditional revascularization therapies.

  15. Transmitted Ultrasound Pressure Variation in Micro Blood Vessel Phantoms

    OpenAIRE

    Qin, Shengping; Kruse, Dustin E; Ferrara, Katherine W.

    2008-01-01

    Silica, cellulose, and polymethylmethacrylate tubes with inner diameters of ten to a few hundred microns are commonly used as blood vessel phantoms in in vitro studies of microbubble or nanodroplet behavior during insonation. However, a detailed investigation of the ultrasonic fields within these micro-tubes has not yet been performed. This technical note provides a theoretical analysis of the ultrasonic fields within micro-tubes. Numerical results show that for the same tube material, the in...

  16. Photoacoustic monitoring and imaging of blood vessels in tissue

    Science.gov (United States)

    Kolkman, Roy G. M.; Pilatou, Magdalena C.; Steenbergen, Wiendelt; de Mul, Frits F. M.

    2002-06-01

    Using very sensitive photoacoustical detectors we localized and monitored the blood content in tissue. In these detectors a PVdF-layer has been used as piezo-electric material and also fibers for the illumination of the sample are integrated. The resolution is about 20micrometers in depth and about 50-100micrometers laterally. The wavelengths of the laser light were 532 and 1064 nm. With these colors we can measure at different depths in tissue. The measurements concerned blood perfusion in real tissue: vessels in chicken breast, in test animals at various positions and in the human arm.

  17. Architecture of the subendothelial elastic fibers of small blood vessels and variations in vascular type and size.

    Science.gov (United States)

    Shinaoka, Akira; Momota, Ryusuke; Shiratsuchi, Eri; Kosaka, Mitsuko; Kumagishi, Kanae; Nakahara, Ryuichi; Naito, Ichiro; Ohtsuka, Aiji

    2013-04-01

    Most blood vessels contain elastin that provides the vessels with the resilience and flexibility necessary to control hemodynamics. Pathophysiological hemodynamic changes affect the remodeling of elastic components, but little is known about their structural properties. The present study was designed to elucidate, in detail, the three-dimensional (3D) architecture of delicate elastic fibers in small vessels, and to reveal their architectural pattern in a rat model. The fine vascular elastic components were observed by a newly developed scanning electron microscopy technique using a formic acid digestion with vascular casts. This method successfully visualized the 3D architecture of elastic fibers in small blood vessels, even arterioles and venules. The subendothelial elastic fibers in such small vessels assemble into a sheet of meshwork running longitudinally, while larger vessels have a higher density of mesh and thicker mesh fibers. The quantitative analysis revealed that arterioles had a wider range of mesh density than venules; the ratio of density to vessel size was higher than that in venules. The new method was useful for evaluating the subendothelial elastic fibers of small vessels and for demonstrating differences in the architecture of different types of vessels.

  18. Functional vessel density in the first month of life in preterm neonates.

    Science.gov (United States)

    Kroth, Julia; Weidlich, Kathrin; Hiedl, Stephan; Nussbaum, Claudia; Christ, Frank; Genzel-boroviczény, Orsolya

    2008-11-01

    Changes in microcirculation have been recognized as central to many disease processes. The aim of this study was to evaluate factors, which influence the microcirculation of the skin during the first month of life in premature infants. Red blood cell (RBC) velocity, vessel diameter, and functional small vessel density (FSVD) were measured daily for the first 30 d on the upper arm in preterm infants with gestational age <30 wk. Orthogonal polarization spectral (OPS) images were analyzed off-line with the Capi- Scope-Image program. In 25 infants, FSVD decreased significantly from week 1 (mean +/- SD 236 +/- 33 cm/cm2) to week 4 (207 +/- 30 cm/cm2) and correlated directly with Hb levels and incubator temperature. Vessel diameters and RBC velocity did not change significantly, nor did clinical parameters such as blood pressure, heart rate or body temperature. Microvascular parameters were not dependent on gestational or postnatal age. The microcirculation of the skin might be an easily accessible window to obtain better understanding of circulatory changes in the postnatal period. Our data are essential as basis for further studies in this field. Hb levels and possible incubator temperatures have a substantial influence on functional small vessel density and therefore need to be taken in account. PMID:18596573

  19. Active Path Selection of Fluid Microcapsules in Artificial Blood Vessel by Acoustic Radiation Force

    Science.gov (United States)

    Masuda, Kohji; Muramatsu, Yusuke; Ueda, Sawami; Nakamoto, Ryusuke; Nakayashiki, Yusuke; Ishihara, Ken

    2009-07-01

    Micrometer-sized microcapsules collapse upon exposure to ultrasound. Use of this phenomenon for a drug delivery system (DDS), not only for local delivery of medication but also for gene therapy, should be possible. However, enhancing the efficiency of medication is limited because capsules in suspension diffuse in the human body after injection, since the motion of capsules in blood flow cannot be controlled. To control the behavior of microcapsules, acoustic radiation force was introduced. We detected local changes in microcapsule density by producing acoustic radiation force in an artificial blood vessel. Furthermore, we theoretically estimated the conditions required for active path selection of capsules at a bifurcation point in the artificial blood vessel. We observed the difference in capsule density at both in the bifurcation point and in alternative paths downstream of the bifurcation point for different acoustic radiation forces. Comparing the experimental results with those obtained theoretically, the conditions for active path selection were calculated from the acoustic radiation force and fluid resistance of the capsules. The possibility of controlling capsule flow towards a specific point in a blood vessel was demonstrated.

  20. Modeling Of Blood Vessel Constriction In 2-D Case Using Molecular Dynamics Method

    CERN Document Server

    Rendi, Mohamad; Viridi, Sparisoma

    2013-01-01

    Blood vessel constriction is simulated with particle-based method using a molecular dynamics authoring software known as Molecular Workbench (WM). Blood flow and vessel wall, the only components considered in constructing a blood vessel, are all represented in particle form with interaction potentials: Lennard-Jones potential, push-pull spring potential, and bending spring potential. Influence of medium or blood plasma is accommodated in plasma viscosity through Stokes drag force. It has been observed that pressure p is increased as constriction c is increased. Leakage of blood vessel starts at 80 % constriction, which shows existence of maximum pressure that can be overcome by vessel wall.

  1. Angiogenesis and blood vessel stability in inflammatory arthritis.

    LENUS (Irish Health Repository)

    Kennedy, Aisling

    2012-02-01

    OBJECTIVE: To assess blood vessel stability in inflammatory synovial tissue (ST) and to examine neural cell adhesion molecule (NCAM), oxidative DNA damage, and hypoxia in vivo. METHODS: Macroscopic vascularity and ST oxygen levels were determined in vivo in patients with inflammatory arthritis who were undergoing arthroscopy. Vessel maturity\\/stability was quantified in matched ST samples by dual immunofluorescence staining for factor VIII (FVIII)\\/alpha-smooth muscle actin (alpha-SMA). NCAM and 8-oxo-7,8-dihydro-2\\'-deoxyguanosine (8-oxodG) were examined by immunohistochemistry. Angiogenesis was assessed in vitro, using human dermal endothelial cells (HDECs) in a Matrigel tube formation assay. RESULTS: A significant number of immature vessels (showing no pericyte recruitment) was observed in tissue from patients with inflammatory arthritis (P < 0.001), in contrast to osteoarthritic and normal tissue, which showed complete recruitment of pericytes. Low in vivo PO(2) levels in the inflamed joint (median [range] 22.8 [3.2-54.1] mm Hg) were inversely related to increased macroscopic vascularity (P < 0.04) and increased microscopic expression of FVIII and alpha-SMA (P < 0.04 and P < 0.03, respectively). A significant proportion of vessels showed focal expression of NCAM and strong nuclear 8-oxodG expression, implicating a loss of EC-pericyte contact and increased DNA damage, levels of which were inversely associated with low in vivo PO(2) (P = 0.04 for each comparison). Circulating cells were completely negative for 8-oxodG. Exposure of HDEC to 3% O(2) (reflecting mean ST in vivo measurements) significantly increased EC tube formation (P < 0.05). CONCLUSION: Our findings indicate the presence of unstable vessels in inflamed joints associated with hypoxia, incomplete EC-pericyte interactions, and increased DNA damage. These changes may further contribute to persistent hypoxia in the inflamed joint to further drive this unstable microenvironment.

  2. Plasma membrane electron transport in frog blood vessels

    Indian Academy of Sciences (India)

    Rashmi P Rao; K Nalini; J Prakasa Rao

    2009-12-01

    In an attempt to see if frog blood vessels possess a plasma membrane electron transport system, the postcaval vein and aorta isolated from Rana tigrina were tested for their ability to reduce ferricyanide, methylene blue, and 2,6-dichloroindophenol. While the dyes remained unchanged, ferricyanide was reduced to ferrocyanide. This reduction was resistant to inhibition by cyanide and azide. Heptane extraction or formalin fixation of the tissues markedly reduced the capability to reduce ferricyanide. Denuded aortas retained only 30% of the activity of intact tissue. Our results indicate that the amphibian postcaval vein and aorta exhibit plasma membrane electron transport

  3. Microfluidic strategy to investigate dynamics of small blood vessel function

    Science.gov (United States)

    Yasotharan, Sanjesh; Bolz, Steffen-Sebastian; Guenther, Axel

    2010-11-01

    Resistance arteries (RAs, 30-300 microns in diameter) that are located within the terminal part of the vascular tree regulate the laminar perfusion of tissue with blood, via the peripheral vascular resistance, and hence controls the systemic blood pressure. The structure of RAs is adapted to actively controlling flow resistance by dynamically changing their diameter, which is non-linearly dependent on the temporal variation of the transmural pressure, perfusion flow rate and spatiotemporal changes in the chemical environment. Increases in systemic blood pressure (hypertension) resulting from pathologic changes in the RA response represent the primary risk factor for cardiovascular diseases. We use a microfluidic strategy to investigate small blood vessels by quantifying structural variations within the arterial wall, RA outer contour and diameter over time. First, we document the artery response to vasomotor drugs that were homogeneously applied at step-wise increasing concentration. Second, we investigate the response in the presence of well-defined axial and circumferential heterogeneities. Artery per- and superfusion is discussed based on microscale PIV measurements of the fluid velocity on both sides of the arterial wall. Structural changes in the arterial wall are quantified using cross-correlation and proper orthogonal decomposition analyses of bright-field micrographs.

  4. BIFURCATION OF FLOW AND MASS TRANSPORT IN A CURVED BLOOD VESSEL

    Institute of Scientific and Technical Information of China (English)

    TAN Wenchang(谭文长); WEI Lan(魏兰); ZHAO Yaohua(赵耀华); TAKASHI Masuoka

    2003-01-01

    A numerical analysis of flow and concentration fields of macromolecules in a slightly curved blood vessel was carried out. Based on these results, the effect of the bifurcation of a flow on the mass transport in a curved blood vessel was discussed. The macromolecules turned out to be easier to deposit in the inner part of the curved blood vessel near the critical Dean number. Once the Dean number is higher than the critical number, the bifurcation of the flow appears. This bifurcation can prevent macromolecules from concentrating in the inner part of the curved blood vessel. This result is helpful for understanding the possible correlations between the blood dynamics and atherosclerosis.

  5. Two and Three Dimensional Blood Flow Simulations in Different Types of Blood Vessels

    Directory of Open Access Journals (Sweden)

    Balazs ALBERT

    2015-12-01

    Full Text Available In this paper we present a synthesis of our results obtained on blood flow simulation in different types of blood vessels. We present first some remarks on the wall shear stress (WSS in the case of a human abdominal aortic aneurysm (AAA, and then we concentrate on the mechanical conditions which would lead to the “rupture” of the vascular vessel with aneurysm and implicitly to a possible stroke. We also make some investigations on the Fahraeus-Lindqvist effect in arterioles. Considering an axial-symmetric reservoir full of blood and which is linked to an arteriole (with the same particular geometry, we have pointed out the concentration of the red blood cells in this arteriole towards the core of the vessel. To improve our work we have considered a real three-dimensional geometry, which is a serious jump versus our previous results, where only the axial-symmetric geometries were considered. In this respect we have reconsidered the case of a carotid artery stenosis with and without a stent.

  6. A Functional Requirement for Astroglia in Promoting Blood Vessel Development in the Early Postnatal Brain

    OpenAIRE

    Shang Ma; Hyo Jun Kwon; Zhen Huang

    2012-01-01

    Astroglia are a major cell type in the brain and play a key role in many aspects of brain development and function. In the adult brain, astrocytes are known to intimately ensheath blood vessels and actively coordinate local neural activity and blood flow. During development of the neural retina, blood vessel growth follows a meshwork of astrocytic processes. Several genes have also been implicated in retinal astrocytes for regulating vessel development. This suggests a role of astrocytes in p...

  7. Pattern of blood vessels in eyes with coloboma

    Directory of Open Access Journals (Sweden)

    Gopal Lingam

    2013-01-01

    Full Text Available Background: Choroidal coloboma, especially with optic disc involvement affects the blood vessel (BV pattern in the fundus. Aim: The aim of this study was to report the observations on the pattern of retinal BVs in eyes with fundus coloboma. Design: Retrospective observational study. Materials and Methods: Twenty four eyes of 19 patients with fundus coloboma and the disc involvement in the coloboma was classified according to a previous publication. Results: Four varieties of BVs were identified in the area of coloboma - BVs that were continuous with those arising from the optic disc; vessels emanating from the floor of coloboma whose continuity with central retinal artery or its branches could be indirectly established; and those emanating from the floor of coloboma whose continuity with central retinal artery could not be established. In addition, extraocular BVs were visible through the thinned sclera. The retinal BVs often traversed the coloboma to reach the normal retina. The disc itself was found to be small and had no physiological cup (if not colobomatous. Conclusions: One should be aware of the major BVs transgressing the coloboma while performing relaxing cuts in the intercalary membrane, during the surgery for retinal detachments in eyes with coloboma. Physiological cup is usually absent (when the disc is not colobomatous. Hence, any cupping in such eyes should be viewed with suspicion.

  8. Launch Conditions Might Affect the Formation of Blood Vessel in the Quail Chorioallantoic Membrane

    Science.gov (United States)

    Henry, M. K.; Unsworth, B. R.; Sychev, B. R.; Guryeva, T. S.; Dadasheva, O. A.; Piert, S. J.; Lagel, K. E.; Dubrovin, L. C.; Jahns, G. C.; Boda, K.; Sabo, V.; Samet, M. M.; Lelkes, P. I.

    1998-01-01

    AS 2 part of the first joint USA-Russian MIR/Shuttle program, fertilized quail eggs were flown on the MIR 18 mission. Post-flight examination indicated impaired survival of both the embryos in space and also of control embryos exposed to vibrational and g-forces simulating the conditions experienced during the launch of Progress 227. We hypothesized that excess mechanical forces and/or other conditions during the launch might cause abnormal development of the blood supply in the chorioallantoic membrane (CAM) leading to the impaired survival of the embryos. The CAM, a highly vascularized extraembryonic organ, provides for the oxygen exchange across the egg shell and is thus pivotal for proper embryonic development. To test our hypothesis, we compared angiogenesis In CAMS of eggs which were either exposed to the vibration and g-force profile simulating the conditions at launch of Progress 227 (synchronous controls), or kept under routine conditions in a laboratory Incubator (laboratory controls). At various time points during Incubation, the eggs were fixed in paraformaldehyde for subsequent dissection. At the time of dissection, the CAM was carefully lifted from the egg shell and examined as whole mounts by bright-field and fluorescent microscopy. The development or the vasculature (angiogenesis) was assessed from the density of blood vessels per viewing field and evaluated by computer aided image analysis. We observed a significant decrease In blood-vessel density in the synchronous controls versus "normal" laboratory controls beginning from day 10 of Incubation. The decrease in vascular density was restricted to the smallest vessels only, suggesting that conditions during the launch and/or during the subsequent Incubation of the eggs may affect the normal progress of angiogenesis in the CAM. Abnormal angiogenesis In the CAM might contribute to the impaired survival of the embryos observed in synchronous controls as well as in space.

  9. Blood Vessel Normalization in the Hamster Oral Cancer Model for Experimental Cancer Therapy Studies

    Energy Technology Data Exchange (ETDEWEB)

    Ana J. Molinari; Romina F. Aromando; Maria E. Itoiz; Marcela A. Garabalino; Andrea Monti Hughes; Elisa M. Heber; Emiliano C. C. Pozzi; David W. Nigg; Veronica A. Trivillin; Amanda E. Schwint

    2012-07-01

    Normalization of tumor blood vessels improves drug and oxygen delivery to cancer cells. The aim of this study was to develop a technique to normalize blood vessels in the hamster cheek pouch model of oral cancer. Materials and Methods: Tumor-bearing hamsters were treated with thalidomide and were compared with controls. Results: Twenty eight hours after treatment with thalidomide, the blood vessels of premalignant tissue observable in vivo became narrower and less tortuous than those of controls; Evans Blue Dye extravasation in tumor was significantly reduced (indicating a reduction in aberrant tumor vascular hyperpermeability that compromises blood flow), and tumor blood vessel morphology in histological sections, labeled for Factor VIII, revealed a significant reduction in compressive forces. These findings indicated blood vessel normalization with a window of 48 h. Conclusion: The technique developed herein has rendered the hamster oral cancer model amenable to research, with the potential benefit of vascular normalization in head and neck cancer therapy.

  10. The vascular Ca2+-sensing receptor regulates blood vessel tone and blood pressure.

    Science.gov (United States)

    Schepelmann, M; Yarova, P L; Lopez-Fernandez, I; Davies, T S; Brennan, S C; Edwards, P J; Aggarwal, A; Graça, J; Rietdorf, K; Matchkov, V; Fenton, R A; Chang, W; Krssak, M; Stewart, A; Broadley, K J; Ward, D T; Price, S A; Edwards, D H; Kemp, P J; Riccardi, D

    2016-02-01

    The extracellular calcium-sensing receptor CaSR is expressed in blood vessels where its role is not completely understood. In this study, we tested the hypothesis that the CaSR expressed in vascular smooth muscle cells (VSMC) is directly involved in regulation of blood pressure and blood vessel tone. Mice with targeted CaSR gene ablation from vascular smooth muscle cells (VSMC) were generated by breeding exon 7 LoxP-CaSR mice with animals in which Cre recombinase is driven by a SM22α promoter (SM22α-Cre). Wire myography performed on Cre-negative [wild-type (WT)] and Cre-positive (SM22α)CaSR(Δflox/Δflox) [knockout (KO)] mice showed an endothelium-independent reduction in aorta and mesenteric artery contractility of KO compared with WT mice in response to KCl and to phenylephrine. Increasing extracellular calcium ion (Ca(2+)) concentrations (1-5 mM) evoked contraction in WT but only relaxation in KO aortas. Accordingly, diastolic and mean arterial blood pressures of KO animals were significantly reduced compared with WT, as measured by both tail cuff and radiotelemetry. This hypotension was mostly pronounced during the animals' active phase and was not rescued by either nitric oxide-synthase inhibition with nitro-l-arginine methyl ester or by a high-salt-supplemented diet. KO animals also exhibited cardiac remodeling, bradycardia, and reduced spontaneous activity in isolated hearts and cardiomyocyte-like cells. Our findings demonstrate a role for CaSR in the cardiovascular system and suggest that physiologically relevant changes in extracellular Ca(2+) concentrations could contribute to setting blood vessel tone levels and heart rate by directly acting on the cardiovascular CaSR.

  11. MACROMICROSCOPIC AND ULTRAMICROSCOPIC CHARACTERISTICS OF THE HART AND ITS BLOOD VESSELS IN MICE EHRLICHIOSIS INFECTION

    Directory of Open Access Journals (Sweden)

    Pokhil S. I.

    2013-12-01

    Full Text Available The macromicroscopic, ultramicroscopic studying change’s in the hart and its blood vessels in unlinear immunocomprometive laboratory male and female mice with the experimental ehrlichiosis is presented in this article. The cardiac destructive and degenerative changes,cardiomyopathy, cardiosclerosis had been established inexperimental animal group’s. The blood vessels endothelial lieyr disorganization, stasis, thrombosis has been noted.

  12. Determination of the critical buckling pressure of blood vessels using the energy approach.

    Science.gov (United States)

    Han, Hai-Chao

    2011-03-01

    The stability of blood vessels under lumen blood pressure is essential to the maintenance of normal vascular function. Differential buckling equations have been established recently for linear and nonlinear elastic artery models. However, the strain energy in bent buckling and the corresponding energy method have not been investigated for blood vessels under lumen pressure. The purpose of this study was to establish the energy equation for blood vessel buckling under internal pressure. A buckling equation was established to determine the critical pressure based on the potential energy. The critical pressures of blood vessels with small tapering along their axis were estimated using the energy approach. It was demonstrated that the energy approach yields both the same differential equation and critical pressure for cylindrical blood vessel buckling as obtained previously using the adjacent equilibrium approach. Tapering reduced the critical pressure of blood vessels compared to the cylindrical ones. This energy approach provides a useful tool for studying blood vessel buckling and will be useful in dealing with various imperfections of the vessel wall.

  13. [Effects of high intensity focused ultrasound with SonoVue on blood vessels pathological examinations].

    Science.gov (United States)

    Qin, Yan; Bai, Jin; Li, Faqi; Wang, Zhibiao

    2010-12-01

    The injury of tumor blood vessels will break up the nutrition supply for the tumor. In this paper, we investigated the effects exerted by high intensity focused ultrasound (HIFU) combined with ultrasound microbubble agent on blood vessels. Ultrasound diagnosis was used to find the goat hepatic blood vessels each being approximately 3mm in diameter. HIFU was focused on the blood vessels. The acoustic power was 250W; HIFU irradiating Mode was line scan (the length of the line: 10 mm; speed: 3 mm/s; irradiating time: 30s). In the experimental group, 0.03 ml/kg SonoVue was injected into the goat before HIFU irradiation,while normal saline was given to the control group. The goats were killed at 24h after HIFU irradiation, then goat liver tissues and blood vessels of target area were taken out. HE staining and Victoria's blue and Ponceau's staining of tissue section showed that the endothelial cells of blood vessels dropped off and became necrosed, and the continuity of blood vessels was interrupted. HIFU combined with SonoVue will damage large blood vessels on HIFU focus, but there is no evident discrepancy between the group with SonoVue and the group without SonoVue.

  14. Biological and engineering design considerations for vascular tissue engineered blood vessels (TEBVs)

    OpenAIRE

    Fernandez, Cristina E.; Achneck, Hardean E.; Reichert, William M.; Truskey, George A.

    2014-01-01

    Considerable advances have occurred in the development of tissue-engineered blood vessels (TEBVs) to repair or replace injured blood vessels, or as in vitro systems for drug toxicity testing. Here we summarize approaches to produce TEBVs and review current efforts to (1) identify suitable cell sources for the endothelium and vascular smooth muscle cells, (2) design the scaffold to mimic the arterial mechanical properties and (3) regulate the functional state of the cells of the vessel wall. I...

  15. Transmitted ultrasound pressure variation in micro blood vessel phantoms.

    Science.gov (United States)

    Qin, Shengping; Kruse, Dustin E; Ferrara, Katherine W

    2008-06-01

    Silica, cellulose and polymethylmethacrylate tubes with inner diameters of ten to a few hundred microns are commonly used as blood vessel phantoms in in vitro studies of microbubble or nanodroplet behavior during insonation. However, a detailed investigation of the ultrasonic fields within these micro-tubes has not yet been performed. This work provides a theoretical analysis of the ultrasonic fields within micro-tubes. Numerical results show that for the same tube material, the interaction between the micro-tube and megaHertz-frequency ultrasound may vary drastically with incident frequency, tube diameter and wall thickness. For 10 MHz ultrasonic insonation of a polymethylmethacrylate (PMMA) tube with an inner diameter of 195 microm and an outer diameter of 260 microm, the peak pressure within the tube can be up to 300% of incident pressure amplitude. However, using 1 MHz ultrasound and a silica tube with an inner diameter of 12 microm and an outer diameter of 50 microm, the peak pressure within the tube is only 12% of the incident pressure amplitude and correspondingly, the spatial-average-time-average intensity within the tube is only 1% of the incident intensity. PMID:18395962

  16. Tumor blood vessels formation in osteosarcoma:vasculogenesis mimicry

    Institute of Scientific and Technical Information of China (English)

    蔡宣松; 贾永伟; 梅炯; 汤如勇

    2004-01-01

    Background Osteosarcoma is characterized by high neovascularization and a high propensity for metastasis through bloodstream. This study was to examine whether there is evidence for vasculogenic mimicry in osteosarcoma and to illustrate mechanism of tumor blood vessels formation in osteosarcoma.Methods Osteosarcoma cell lines (U-2OS) were tested for their ability to form tubular networks in three-dimensional culture containing type Ⅰ collagen. The structures of the tubular networks were observed with phase contrast microscope and transmission electron microscope (TEM). Morphometric studies using hematoxylin and eosin (HE) stain and CD31 immunohistochemical stain to show tumor-lined channels in human osteosarcoma were also performed.Results Observation with light microscope and TEM showed that highly aggressive osteosarcoma cell lines (U-2OS) formed networks containing channels when grown in three-dimensional culture containing type Ⅰ collagen, in the absence of endothelial cells or fibroblasts. Morphometric observation using HE stain and CD31 immunohistochemical stain showed that tumor cell-lined channels were also detected in vivo in osteosarcoma; by comparison, all vascular areas in the pedicel of osteochondroma or outside osteochondroma were endothelial-lined.Conclusion These observations strongly suggest that aggressive osteosarcoma cells may generate vascular channels that facilitate tumor perfusion independent of tumor angiogenesis and have the ability of vasculogenic mimicry.

  17. An Experimental Study to Replace the Thoracic Descending Aorta for Pigs with a Self-Made Sutureless Blood Vessel

    OpenAIRE

    Song, Fenglin; Zhou, Wenwu; Tang, Tao; Li, Xiaobing; Wu, Xiaoming; Yang, Jinfu

    2014-01-01

    To simplify the procedure of blood vessel replacement operation and shorten the vascular anastomosis time, we developed a special artificial blood vessel which can be connected to native blood vessels without suture. The self-made sutureless blood vessel (SMSBV) was made from two titanium connectors and a Gore-Tex graft. To investigate blood compatibility and histocompatibility of the SMSBV, we carried thoracic descending aorta replacement using either SMSBV or Gore-Tex, respectively, in pigs...

  18. An Experimental Study to Replace the Thoracic Descending Aorta for Pigs with a Self-Made Sutureless Blood Vessel

    OpenAIRE

    2014-01-01

    To simplify the procedure of blood vessel replacement operation and shorten the vascular anastomosis time, we developed a special artificial blood vessel which can be connected to native blood vessels without suture. The self-made sutureless blood vessel (SMSBV) was made from two titanium connectors and a Gore-Tex graft. To investigate blood compatibility and histocompatibility of the SMSBV, we carried thoracic descending aorta replacement using either SMSBV or Gore-Tex,...

  19. Automated computational framework of blood vessel quantification in chick chorioallantoic membrane angiogenesis.

    Science.gov (United States)

    Shi, Peng; Hong, Jinsheng; Huang, Yue; Zhang, Zhenhuan; Zhang, Mei; Zhang, Lurong

    2014-01-01

    Chick chorioallantoic membrane (CAM) angiogenesis assay has been widely used for finding drugs targeting new blood vessel development in cancer research. In addition to the setup materials and protocols, laboratory findings depend on the quantification and analysis of microscopic blood vessel images. However, it is still a challenging problem because of the high complexity of blood vessel branching structures. We applied preprocessing on CAM microscopic images by keeping the integrity of minor branches in the vessel structure. We then proposed an efficient way to automatically extract blood vessel centerlines based on vector tracing starting from detected seed points. Finally, all branches were coded to construct an abstract model of the branching structure, which enabled more accurate modeling for in-depth analysis. The framework was applied in quantifying Icaritin (ICT) inhibition effects on angiogenesis in a CAM model. Experimental results showed the high accuracy in blood vessel quantification and modeling compared with semimanual measurements. Meanwhile, a set of blood vessel growth indicators were extracted to provide fully automated analysis for angiogenesis assays. Further analysis proved that ICT took effect in a dose-dependent manner which could be applied in suppressing tumor blood vessel growth. PMID:25277148

  20. Effect of non-Newtonian characteristics of blood on magnetic particle capture in occluded blood vessel

    Energy Technology Data Exchange (ETDEWEB)

    Bose, Sayan; Banerjee, Moloy, E-mail: moloy_kb@yahoo.com

    2015-01-15

    Magnetic nanoparticles drug carriers continue to attract considerable interest for drug targeting in the treatment of cancer and other pathological conditions. Magnetic carrier particles with surface-bound drug molecules are injected into the vascular system upstream from the desired target site, and are captured at the target site via a local applied magnetic field. Herein, a numerical investigation of steady magnetic drug targeting (MDT) using functionalized magnetic micro-spheres in partly occluded blood vessel having a 90° bent is presented considering the effects of non-Newtonian characteristics of blood. An Eulerian–Lagrangian technique is adopted to resolve the hemodynamic flow and the motion of the magnetic particles in the flow using ANSYS FLUENT. An implantable infinitely long cylindrical current carrying conductor is used to create the requisite magnetic field. Targeted transport of the magnetic particles in a partly occluded vessel differs distinctly from the same in a regular unblocked vessel. Parametric investigation is conducted and the influence of the insert configuration and its position from the central plane of the artery (z{sub offset}), particle size (d{sub p}) and its magnetic property (χ) and the magnitude of current (I) on the “capture efficiency” (CE) is reported. Analysis shows that there exists an optimum regime of operating parameters for which deposition of the drug carrying magnetic particles in a target zone on the partly occluded vessel wall can be maximized. The results provide useful design bases for in vitro set up for the investigation of MDT in stenosed blood vessels. - Highlights: • Two counter rotating vortices forces the fluid flow back through the more viscous region. • The existence of strong recirculation zone just downstream side of the occlusion. • Configuration 4 produces the better efficient MDT system. • Modified Casson model predicts the highest value of CE, whereas the generalized power law gives

  1. Effect of non-Newtonian characteristics of blood on magnetic particle capture in occluded blood vessel

    International Nuclear Information System (INIS)

    Magnetic nanoparticles drug carriers continue to attract considerable interest for drug targeting in the treatment of cancer and other pathological conditions. Magnetic carrier particles with surface-bound drug molecules are injected into the vascular system upstream from the desired target site, and are captured at the target site via a local applied magnetic field. Herein, a numerical investigation of steady magnetic drug targeting (MDT) using functionalized magnetic micro-spheres in partly occluded blood vessel having a 90° bent is presented considering the effects of non-Newtonian characteristics of blood. An Eulerian–Lagrangian technique is adopted to resolve the hemodynamic flow and the motion of the magnetic particles in the flow using ANSYS FLUENT. An implantable infinitely long cylindrical current carrying conductor is used to create the requisite magnetic field. Targeted transport of the magnetic particles in a partly occluded vessel differs distinctly from the same in a regular unblocked vessel. Parametric investigation is conducted and the influence of the insert configuration and its position from the central plane of the artery (zoffset), particle size (dp) and its magnetic property (χ) and the magnitude of current (I) on the “capture efficiency” (CE) is reported. Analysis shows that there exists an optimum regime of operating parameters for which deposition of the drug carrying magnetic particles in a target zone on the partly occluded vessel wall can be maximized. The results provide useful design bases for in vitro set up for the investigation of MDT in stenosed blood vessels. - Highlights: • Two counter rotating vortices forces the fluid flow back through the more viscous region. • The existence of strong recirculation zone just downstream side of the occlusion. • Configuration 4 produces the better efficient MDT system. • Modified Casson model predicts the highest value of CE, whereas the generalized power law gives the least

  2. Primo Vascular System Accompanying a Blood Vessel from Tumor Tissue and a Method to Distinguish It from the Blood or the Lymph System

    Directory of Open Access Journals (Sweden)

    Jaekwan Lim

    2013-01-01

    Full Text Available A primo vessel was observed in the abdominal cavity in the lung cancer mouse model, and its function as an extra metastatic path was observed. In this work, we found a primo vessel accompanying a blood vessel emanating from a tumor in the skin. We also presented simple and efficient criteria to distinguish a primo vessel from a blood or a lymph vessel and from a nerve. The criteria for using DAPI and Phalloidin will be useful in clinical situations to find and identify the primo vessels among the blood vessels, lymph vessels, or nerves in the tissue surrounding a tumor such as a melanoma or breast cancer.

  3. Development of an accurate 3D blood vessel searching system using NIR light

    Science.gov (United States)

    Mizuno, Yoshifumi; Katayama, Tsutao; Nakamachi, Eiji

    2010-02-01

    Health monitoring system (HMS) and drug delivery system (DDS) require accurate puncture by needle for automatic blood sampling. In this study, we develop a miniature and high accurate automatic 3D blood vessel searching system. The size of detecting system is 40x25x10 mm. Our searching system use Near-Infrared (NIR) LEDs, CMOS camera modules and image processing units. We employ the stereo method for searching system to determine 3D blood vessel location. Blood vessel visualization system adopts hemoglobin's absorption characterization of NIR light. NIR LED is set behind the finger and it irradiates Near Infrared light for the finger. CMOS camera modules are set in front of the finger and it captures clear blood vessel images. Two dimensional location of the blood vessel is detected by luminance distribution of the image and its depth is calculated by the stereo method. 3D blood vessel location is automatically detected by our image processing system. To examine the accuracy of our detecting system, we carried out experiments using finger phantoms with blood vessel diameters, 0.5, 0.75, 1.0mm, at the depths, 0.5 ~ 2.0 mm, under the artificial tissue surface. Experimental results of depth obtained by our detecting system showed good agreements with given depths, and the availability of this system is confirmed.

  4. Estimation of vessel diameter and blood flow dynamics from laser speckle images

    DEFF Research Database (Denmark)

    Postnov, Dmitry D.; Tuchin, Valery V.; Sosnovtseva, Olga

    2016-01-01

    Laser speckle imaging is a rapidly developing method to study changes of blood velocity in the vascular networks. However, to assess blood flow and vascular responses it is crucial to measure vessel diameter in addition to blood velocity dynamics. We suggest an algorithm that allows for dynamical...... masking of a vessel position and measurements of it's diameter from laser speckle images. This approach demonstrates high reliability and stability....

  5. Human Blood-Vessel-Derived Stem Cells for Tissue Repair and Regeneration

    OpenAIRE

    Chien-Wen Chen; Mirko Corselli; Bruno Péault; Johnny Huard

    2012-01-01

    Multipotent stem/progenitor cells with similar developmental potentials have been independently identified from diverse human tissue/organ cultures. The increasing recognition of the vascular/perivascular origin of mesenchymal precursors suggested blood vessels being a systemic source of adult stem/progenitor cells. Our group and other laboratories recently isolated multiple stem/progenitor cell subsets from blood vessels of adult human tissues. Each of the three structural layers of blood ve...

  6. Estimation of vessel diameter and blood flow dynamics from laser speckle images

    Science.gov (United States)

    Postnov, Dmitry D.; Tuchin, Valery V.; Sosnovtseva, Olga

    2016-01-01

    Laser speckle imaging is a rapidly developing method to study changes of blood velocity in the vascular networks. However, to assess blood flow and vascular responses it is crucial to measure vessel diameter in addition to blood velocity dynamics. We suggest an algorithm that allows for dynamical masking of a vessel position and measurements of it’s diameter from laser speckle images. This approach demonstrates high reliability and stability.

  7. Laser optical method of visualizing cutaneous blood vessels and its applications in biometry and photomedicine

    Science.gov (United States)

    Asimov, M. M.; Asimov, R. M.; Rubinov, A. N.

    2011-05-01

    We propose and examine a new approach to visualizing a local network of cutaneous blood vessels using laser optical methods for applications in biometry and photomedicine. Various optical schemes of the formation of biometrical information on the architecture of blood vessels of skin tissue are analyzed. We developed an optical model of the interaction of the laser radiation with the biological tissue and a mathematical algorithm of processing of measurement results. We show that, in medicine, the visualization of blood vessels makes it possible to calculate and determine regions of disturbance of blood microcirculation and to control tissue hypoxia, as well as to maintain the local concentration of oxygen at a level necessary for the normal cellular metabolism. We propose noninvasive optical methods for modern photomedicine and biometry for diagnostics and elimination of tissue hypoxia and for personality identification and verification via the pattern of cutaneous blood vessels.

  8. Lymphatic and blood vessels in basal and triple-negative breast cancers: characteristics and prognostic significance.

    Science.gov (United States)

    Mohammed, Rabab A A; Ellis, Ian O; Mahmmod, Ali M; Hawkes, E Claire; Green, Andrew R; Rakha, Emad A; Martin, Stewart G

    2011-06-01

    Basal and triple-negative breast cancer phenotypes are characterised by unfavourable biological behaviour and outcome. Although certain studies have examined their pathological and molecular profile, the vascular characteristics of lymphatic and blood vessels have not been examined. Immunohistochemical staining with podoplanin, CD34 and CD31 was used to examine lymphatic and microvessel density, as well as vascular invasion in 197 basal-like and in 99 triple-negative breast tumours and compared against 200 non-basal and 334 non-triple-negative cases. All specimens were lymph node negative. Vascular invasion was identified as blood or lymphatic vascular invasion by the differential expression of markers. All measurements were correlated with clinicopathological features and prognosis. No significant difference was detected between the basal and triple-negative groups in terms of lymphatic or microvessel density or vascular invasion. However, both the basal and the triple-negative groups showed significantly higher microvessel density than did the non-basal and non-triple-negative groups (P=0.017 and Pcontrols. Interestingly, vascular invasion, almost entirely lymphatic invasion, was detected in 27% of the basal and in 26% of the triple-negative groups with no significant difference in comparison with control groups. In both basal and triple negatives, vascular invasion was associated with poorer survival by univariate and multivariate analyses. The 20-year overall survival rate in basal-like tumours was 55% in vascular invasion-positive cases compared with 73% in vascular invasion-negative tumours (P=0.012), and 46% in triple-negative vascular invasion-positive compared with 79% in vascular invasion-negative tumours (P=0.001). Basal-like vs non-basal-like and triple-negative vs non-triple-negative tumours have similar vascular characteristics in terms of lymphatic vessel density and vascular invasion but higher microvessel density, suggesting that such groups may

  9. An Original Approach for Quantification of Blood Vessels on the Whole Tumour Section

    Directory of Open Access Journals (Sweden)

    Nga Tran Kim

    2003-01-01

    Full Text Available Relative abundance of tumour angiogenesis has been shown to be of clinical relevance in cancers of various locations such as the ovary. Nevertheless, several problems are encountered when quantifying tumour microvessels: (i as many other tumour markers, vascularity pattern is often heterogeneous within the tumour mass and even within the same histological section. As a consequence, an adequate acquisition method must be developed for accurate field sampling. (ii Manual microvessel counting is long, tedious and subject to poor reproducibility. Introduction in routine practice requires a fast, reproducible and reliable automatic image processing. In this study we present an original procedure combining a slide scanner image acquisition and a fully automatic image analysis sequence. The slide scanner offers the advantage of recording an image of the whole histological section for subsequent automatic blood vessel detection and hot spot area location. Microvessel density and surface fraction were measured for the whole section as well as within hot spots. Different immunostaining methods were tested in order to optimise the procedure. Moreover, the method proposed was submitted to a quality control procedure, with reference to interactive identification of microvessels at scanner level. This experiment showed that 93 to 97% of blood vessels were detected, according to the staining protocol used. Colour figures can be viewed on http://www.esacp.org/acp/2003/25‐2/kim.htm.

  10. Do Haematophagous Bugs Assess Skin Surface Temperature to Detect Blood Vessels?

    OpenAIRE

    Raquel A Ferreira; Lazzari, Claudio R.; Marcelo G. Lorenzo; Pereira, Marcos H

    2007-01-01

    Background It is known that some blood-sucking insects have the ability to reach vessels under the host skin with their mouthparts to feed blood from inside them. However, the process by which they locate these vessels remains largely unknown. Less than 5% of the skin is occupied by blood vessels and thus, it is not likely that insects rely on a “random search strategy”, since it would increase the probability of being killed by their hosts. Indeed, heterogeneities along the skin surface migh...

  11. High-resolution ultrasound imaging and noninvasive optoacoustic monitoring of blood variables in peripheral blood vessels

    Science.gov (United States)

    Petrov, Irene Y.; Petrov, Yuriy; Prough, Donald S.; Esenaliev, Rinat O.

    2011-03-01

    Ultrasound imaging is being widely used in clinics to obtain diagnostic information non-invasively and in real time. A high-resolution ultrasound imaging platform, Vevo (VisualSonics, Inc.) provides in vivo, real-time images with exceptional resolution (up to 30 microns) using high-frequency transducers (up to 80 MHz). Recently, we built optoacoustic systems for probing radial artery and peripheral veins that can be used for noninvasive monitoring of total hemoglobin concentration, oxyhemoglobin saturation, and concentration of important endogenous and exogenous chromophores (such as ICG). In this work we used the high-resolution ultrasound imaging system Vevo 770 for visualization of the radial artery and peripheral veins and acquired corresponding optoacoustic signals from them using the optoacoustic systems. Analysis of the optoacoustic data with a specially developed algorithm allowed for measurement of blood oxygenation in the blood vessels as well as for continuous, real-time monitoring of arterial and venous blood oxygenation. Our results indicate that: 1) the optoacoustic technique (unlike pure optical approaches and other noninvasive techniques) is capable of accurate peripheral venous oxygenation measurement; and 2) peripheral venous oxygenation is dependent on skin temperature and local hemodynamics. Moreover, we performed for the first time (to the best of our knowledge) a comparative study of optoacoustic arterial oximetry and a standard pulse oximeter in humans and demonstrated superior performance of the optoacoustic arterial oximeter, in particular at low blood flow.

  12. 论脉之生理特性%Discussion of physiological characteristic of blood vessel

    Institute of Scientific and Technical Information of China (English)

    刘玲

    2011-01-01

    The blood vessel has been named as extraordinary Fu-organ by traditional Chinese medicine. It's role is transporting the blood to nourishing the tissues and organs. As it hide between in the tissues,it lacks of the theories of physiological and pathological characteristics. So more blood vessel's diseases must be treated by adjusting blood. By modern technology,it has been proved that the blood vessel's disease is not only independent existence,but also the main pathological factor of the blood diseases. So preventing the blood vessel diseases,the main method is regulating and nourishing the blood vessel. This article thought that the physiological characteristics of the blood vessel are having unblocked's and nomal contraction or expansion's and solid wall's channel. It's also an organ of more Qi and blood. Besides the heart control,the healthy of blood vessel dependent on the unfold and smooth's liver Qi,and spleen Qi's manage.%传统中医学认为脉是奇恒之腑,具有输送血液濡养组织器官的作用.由于脉深藏于组织之间,故缺乏对脉生理、病理特点的论述,致使脉病多从血论治.现代科技手段证明脉病不仅独立存在,还是导致血病的主要病理因素.调脉、养脉是防治血病的重要环节.认为脉以柔顺畅达、舒缩有度、约束有节为生理特性,为多气多血组织,除心主血脉外,肝气的疏泄及脾气固摄都是脉保持健康、通畅的保证.

  13. Blood vessel growth blocker may treat AIDS-related Kaposi’s sarcoma

    Science.gov (United States)

    Patients with an AIDS-associated cancer, Kaposi's sarcoma (KS), showed improvement after receiving the combination of bevacizumab, a cancer drug that blocks the growth of new blood vessels, and highly active antiretroviral therapy (HAART).

  14. Differential Effects between Cigarette Total Particulate Matter and Cigarette Smoke Extract on Blood and Blood Vessel

    Science.gov (United States)

    Park, Jung-Min; Chang, Kyung-Hwa; Park, Kwang-Hoon; Choi, Seong-Jin; Lee, Kyuhong; Lee, Jin-Yong; Satoh, Masahiko; Song, Seong-Yu; Lee, Moo-Yeol

    2016-01-01

    The generation and collection of cigarette smoke (CS) is a prerequisite for any toxicology study on smoking, especially an in vitro CS exposure study. In this study, the effects on blood and vascular function were tested with two widely used CS preparations to compare the biological effects of CS with respect to the CS preparation used. CS was prepared in the form of total particulate matter (TPM), which is CS trapped in a Cambridge filter pad, and cigarette smoke extract (CSE), which is CS trapped in phosphate-buffered saline. TPM potentiated platelet reactivity to thrombin and thus increased aggregation at a concentration of 25~100 μg/mL, whereas 2.5~10% CSE decreased platelet aggregation by thrombin. Both TPM and CSE inhibited vascular contraction by phenylephrine at 50~100 μg/mL and 10%, respectively. TPM inhibited acetylcholine-induced vasorelaxation at 10~100 μg/mL, but CSE exhibited a minimal effect on relaxation at the concentration that affects vasoconstriction. Neither TPM nor CSE induced hemolysis of erythrocytes or influenced plasma coagulation, as assessed by prothrombin time (PT) and activated partial thromboplastin time (aPTT). Taken together, CS affects platelet activity and deteriorates vasomotor functions in vitro. However, the effect on blood and blood vessels may vary depending on the CS preparation. Therefore, the results of experiments conducted with CS preparations should be interpreted with caution.

  15. Detection of retinal blood vessel changes in multiple sclerosis with optical coherence tomography

    OpenAIRE

    Bhaduri, Basanta; Nolan, Ryan M.; Shelton, Ryan L.; Pilutti, Lara A.; Motl, Robert W.; Moss, Heather E.; Pula, John H.; Boppart, Stephen A.

    2016-01-01

    Although retinal vasculitis is common in multiple sclerosis (MS), it is not known if MS is associated with quantitative abnormalities in retinal blood vessels (BVs). Optical coherence tomography (OCT) is suitable for examining the integrity of the anterior visual pathways in MS. In this paper we have compared the size and number of retinal blood vessels in patients with MS, with and without a history of optic neuritis (ON), and control subjects from the cross-sectional retinal images from OCT...

  16. The Primary Study of the Construction of Small Diameter Tissue-engineered Blood Vessel

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionToday, the blood vessel substitutes are in large demand for coronary and peripheral bypass procedures. Each year, more than 600,000 coronary artery bypass graft procedures are performed in the United States. There are some blood vessel substitutes including autografts, allografts and synthetic grafts that have been applied in vascular surgery in clinics. But their clinical implementations are prevented, especially for the <6mm in diameter grafts, because of their shortcomings such as inadequat...

  17. [The structure of the developing blood vessels of the neocortical anlage of the human embryo].

    Science.gov (United States)

    Korzhevskiĭ, D E; Omel'chenko, N V; Smirnov, E B; Petrova, E S

    2000-01-01

    Using light and electron microscopy the structure of blood vessels of neocortical anlage of human 7-12 embryos was studied. It was shown that at the early stage of formation of intraorgan vascular network the wall of blood vessels of ventricular zone successively differentiate, which is characterized by the appearance of second layer of cells (pericytes), accumulation of basement membrane components, widening of the zone of contacts between endotheliocytes and establishment of the contacts with bipolar cells of neocortex anlage. The morphological data obtained assist in comprehension of physiological aspects of formation of blood brain barrier and regulation of blood flow in human embryonal neocortex.

  18. Differential mechanisms associated with vascular disrupting action of electrochemotherapy: intravital microscopy on the level of single normal and tumor blood vessels.

    Directory of Open Access Journals (Sweden)

    Bostjan Markelc

    Full Text Available Electropermeabilization/electroporation (EP provides a tool for the introduction of molecules into cells and tissues. In electrochemotherapy (ECT, cytotoxic drugs are introduced into cells in tumors, and nucleic acids are introduced into cells in gene electrotransfer. The normal and tumor tissue blood flow modifying effects of EP and the vascular disrupting effect of ECT in tumors have already been determined. However, differential effects between normal vs. tumor vessels, to ensure safety in the clinical application of ECT, have not been determined yet. Therefore, the aim of our study was to determine the effects of EP and ECT with bleomycin on the HT-29 human colon carcinoma tumor model and its surrounding blood vessels. The response of blood vessels to EP and ECT was monitored in real time, directly at the single blood vessel level, by in vivo optical imaging in a dorsal window chamber in SCID mice with 70 kDa fluorescently labeled dextrans. The response of tumor blood vessels to EP and ECT started to differ within the first hour. Both therapies induced a vascular lock, decreased functional vascular density (FVD and increased the diameter of functional blood vessels within the tumor. The effects were more pronounced for ECT, which destroyed the tumor blood vessels within 24 h. Although the vasculature surrounding the tumor was affected by EP and ECT, it remained functional. The study confirms the current model of tumor blood flow modifying effects of EP and provides conclusive evidence that ECT is a vascular disrupting therapy with a specific effect on the tumor blood vessels.

  19. Analyses of thermal stress and fracture during cryopreservation of blood vessel

    Institute of Scientific and Technical Information of China (English)

    华泽钊; 徐红艳; 周国燕; 刘锦纷; 黄惠民; 丁文祥

    2001-01-01

    The occurrence of fractures in the vessel wall has been a major problem for human blood vessel cryopreservation. The large volumetric expansion of water during crystallization produces great inner stresses. To solve these complicated heat transfer and thermal stress problems, a model and an analytic method are presented in this paper, with which transient temperature field, the transient stress field inside the blood vessels during freezing can be calculated and analyzed, and the probable cracks or fractures can be predicted. The analytic results of sheep thoracic artery are consistent with the experimental observations of fractures.

  20. Growth and Remodeling in Blood Vessels Studied In Vivo With Fractal Analysis

    Science.gov (United States)

    Parsons-Wingerter, Patricia A.

    2003-01-01

    Every cell in the human body must reside in close proximity to a blood vessel (within approximately 200 mm) because blood vessels provide the oxygen, metabolite, and fluid exchanges required for cellular existence. The growth and remodeling of blood vessels are required to support the normal physiology of embryonic development, reproductive biology, wound healing and adaptive remodeling to exercise, as well as abnormal tissue change in diseases such as cancer, diabetes, and coronary heart disease. Cardiovascular and hemodynamic (blood flow dynamics) alterations experienced by astronauts during long-term spaceflight, including orthostatic intolerance, fluid shifts in the body, and reduced numbers of red (erythrocyte) and white (immune) blood cells, are identified as risk factors of very high priority in the NASA task force report on risk reduction for human spaceflight, the "Critical Path Roadmap."

  1. Differentiation of smooth muscle progenitor cells in peripheral blood and its application in tissue engineered blood vessels

    Institute of Scientific and Technical Information of China (English)

    Shang-zhe XIE; Ning-tao FANG; Shui LIU; Ping ZHOU; Yi ZHANG; Song-mei WANG; Hong-yang GAO; Luan-feng PAN

    2008-01-01

    Background: A major shortcoming in tissue engineered blood vessels (TEBVs) is the lack of healthy and easily attainable smooth muscle cells (SMCs). Smooth muscle progenitor cells (SPCs), especially from peripheral blood, may offer an alternative cell source for tissue engineering involving a less invasive harvesting technique. Methods: SPCs were isolated from 5-ml fresh rat peripheral blood by density-gradient centrifugation and cultured for 3 weeks in endothelial growth medium-2-MV (EGM-2-MV) medium containing platelet-derived growth factor-BB (PDGF BB). Before seeded on the synthesized scaffold, SPC-derived smooth muscle outgrowth cell (SOC) phenotypes were assessed by immuno-fluorescent staining, Western blot analysis, and reverse transcription polymerase chain reaction (RT-PCR). The cells were seeded onto the silk fibroin-modified poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (SF-PHBHHx) scaffolds by 6×104 cells/cm'2 and cultured under the static con-dition for 3 weeks. The growth and proliferation of the seeded cells on the scaffold were analyzed by 3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide (MTT) assay, scanning electron microscope (SEM), and 4,6-diamidino-2-phenylindole (DAPI) staining. Results: SOCs displayed specific "hill and valley" morphology, expressed the specific markers of the SMC lineage: protein, and extracellular matrix components elastin and matrix Gla protein (MGP), as well as vascular endothelial growth factor (VEGF). After seeded on the SF-PHBHHx scaffold, the cells showed excellent metabolic activity and proliferation. Conclusion: SPCs isolated from peripheral blood can be differentiated into the SMCs in vitro and have an impressive growth potential in the biodegradable synthesized scaffold. Thus, SPCs may be a promising cell source for constructing TEBVs.

  2. Computational study of thermal effects of large blood vessels in human knee joint.

    Science.gov (United States)

    Xue, Xu; He, Zhi Zhu; Liu, Jing

    2013-01-01

    This paper is dedicated to present a comprehensive investigation on the thermal effects of large blood vessels of human knee joint during topical cooling and fomentation treatment. A three-dimensional (3D) finite element analysis by taking full use of the anatomical CAD model of human knee joint was developed to accurately simulate the treatment process. Based on the classical Pennes bio-heat transfer equation, the time evolution of knee joint's temperature distribution and heat flux from large blood vessels was obtained. In addition, we compared several influencing factors and obtained some key conclusions which cannot be easily acquired through clinical experiments. The results indicated that the thermal effects of large blood vessels could remarkably affect the temperature distribution of knee joint during treatment process. Fluctuations of blood flow velocity and metabolic heat production rate affect little on the thermal effects of large blood vessels. Changing the temperature of blood and regimes of treatment could effectively regulate this phenomenon, which is important for many physiological activities. These results provide a guideline to the basic and applied research for the thermally significant large blood vessels in the knee organism.

  3. Application of the Carreau viscosity model to the oscillatory flow in blood vessels

    Science.gov (United States)

    Tabakova, Sonia; Kutev, Nikolay; Radev, Stefan

    2015-11-01

    When studying the oscillatory flow in different types of blood vessels it is very important to know what type of the blood viscosity model has to be used. In general the blood viscosity is defined as a shear-thinning liquid, for which there exist different shear-dependent models, for example the Carreau model, which represents the viscosity as a non-linear function of the shear-rate. In some cases, however, the blood viscosity could be regarded as constant, i.e., the blood is treated as Newtonian fluid. The aim of the present work is to show theoretically and numerically some approximate limits of the Newtonian model application, when the blood vessel is assumed as a 2D straight tube. The obtained results are in agreement with other authors' numerical results based on similar blood viscosity models.

  4. Vascular bursts enhance permeability of tumour blood vessels and improve nanoparticle delivery

    Science.gov (United States)

    Matsumoto, Yu; Nichols, Joseph W.; Toh, Kazuko; Nomoto, Takahiro; Cabral, Horacio; Miura, Yutaka; Christie, R. James; Yamada, Naoki; Ogura, Tadayoshi; Kano, Mitsunobu R.; Matsumura, Yasuhiro; Nishiyama, Nobuhiro; Yamasoba, Tatsuya; Bae, You Han; Kataoka, Kazunori

    2016-06-01

    Enhanced permeability in tumours is thought to result from malformed vascular walls with leaky cell-to-cell junctions. This assertion is backed by studies using electron microscopy and polymer casts that show incomplete pericyte coverage of tumour vessels and the presence of intercellular gaps. However, this gives the impression that tumour permeability is static amid a chaotic tumour environment. Using intravital confocal laser scanning microscopy we show that the permeability of tumour blood vessels includes a dynamic phenomenon characterized by vascular bursts followed by brief vigorous outward flow of fluid (named ‘eruptions’) into the tumour interstitial space. We propose that ‘dynamic vents’ form transient openings and closings at these leaky blood vessels. These stochastic eruptions may explain the enhanced extravasation of nanoparticles from the tumour blood vessels, and offer insights into the underlying distribution patterns of an administered drug.

  5. Tracing retinal blood vessels by matrix-forest theorem of directed graphs.

    Science.gov (United States)

    Cheng, Li; De, Jaydeep; Zhang, Xiaowei; Lin, Feng; Li, Huiqi

    2014-01-01

    This paper aims to trace retinal blood vessel trees in fundus images. This task is far from being trivial as the crossover of vessels are commonly encountered in image-based vessel networks. Meanwhile it is often crucial to separate the vessel tree structures in applications such as diabetic retinopathy analysis. In this work, a novel directed graph based approach is proposed to cast the task as label propagation over directed graphs, such that the graph is to be partitioned into disjoint sub-graphs, or equivalently, each of the vessel trees is traced and separated from the rest of the vessel network. Then the tracing problem is addressed by making novel usage of the matrix-forest theorem in algebraic graph theory. Empirical experiments on synthetic as well as publicly available fundus image datasets demonstrate the applicability of our approach. PMID:25333171

  6. Characteristics of blood vessels forming “sausages-on-a-string” patterns during hypertension

    Science.gov (United States)

    Ravnsborg Beierholm, Ulrik; Christian Brings Jacobsen, Jens; Holstein-Rathlou, Niels-Henrik; Alstrøm, Preben

    2007-03-01

    A phenomenon of alternate constrictions and dilatations in blood vessels has been studied for over 50 years. Recently, a theory has been presented involving a Rayleigh type instability. We analyze the model in terms of the lengths of the deformations in relation to the wall thickness, blood pressure and stress. Analytical and numerical results obtained are consistent with experimental data.

  7. Computational Fluid Dynamics Analysis of Pulsatile Blood Flow Behavior in Modelled Stenosed Vessels with Different Severities

    Directory of Open Access Journals (Sweden)

    Mohsen Mehrabi

    2012-01-01

    Full Text Available This study focuses on the behavior of blood flow in the stenosed vessels. Blood is modelled as an incompressible non-Newtonian fluid which is based on the power law viscosity model. A numerical technique based on the finite difference method is developed to simulate the blood flow taking into account the transient periodic behaviour of the blood flow in cardiac cycles. Also, pulsatile blood flow in the stenosed vessel is based on the Womersley model, and fluid flow in the lumen region is governed by the continuity equation and the Navier-Stokes equations. In this study, the stenosis shape is cosine by using Tu and Devil model. Comparing the results obtained from three stenosed vessels with 30%, 50%, and 75% area severity, we find that higher percent-area severity of stenosis leads to higher extrapressure jumps and higher blood speeds around the stenosis site. Also, we observe that the size of the stenosis in stenosed vessels does influence the blood flow. A little change on the cross-sectional value makes vast change on the blood flow rate. This simulation helps the people working in the field of physiological fluid dynamics as well as the medical practitioners.

  8. Relationship between Lymphatic Vessel Density and Lymph Node Metastasis of Invasive Micropapillary Carcinoma of the Breast

    Institute of Scientific and Technical Information of China (English)

    Xiaojing Guo; Ling Chen; Ronggang Lang; Yu Fan; Li Fu

    2006-01-01

    OBJECTIVE To investigate the relationship between lymphatic vessel density and lymph node metastasis of invasive micropapillary carcinoma (IMPC) of the breast.METHODS The immunohistochemical study for vascular endothelial growth factor-c (VEGF-C), VEGF Receptor-3 (VEGFR-3) and lymphatic vessel density of 51 cases of IMPC were performed, and lymph node metastases were examined by microscopic analysis of these cases.RESULTS In IMPC, VEGF-C was expressed in the cytoplasm and/or on the membrane of the tumor cells, and the expression of VEGF-C showed a positive correlation with lymph node metastasis (P<0.01). Lymphatic vessel density was determined by the number of micro-lymphatic vessels with VEGFR-3 positive staining. Lymphatic vessel density was positively correlated with VEGF-C expression (P<0.01) and lymph node metastasis (P<0.01). The percentage of IMPC in the tumor was not associated with the incidence of lymph node metastasis. The metastatic foci in lymph nodes were either pure or predominant micropapillary carcinoma.CONCLUSION The results suggested that VEGF-C overexpression stimulated tumor lymphangiogenesis, and the increased lymphatic vessel density may be the key factor that influenced lymph node metastasis of IMPC.

  9. Blood vessel extraction and optic disc removal using curvelet transform and kernel fuzzy c-means.

    Science.gov (United States)

    Kar, Sudeshna Sil; Maity, Santi P

    2016-03-01

    This paper proposes an automatic blood vessel extraction method on retinal images using matched filtering in an integrated system design platform that involves curvelet transform and kernel based fuzzy c-means. Since curvelet transform represents the lines, the edges and the curvatures very well and in compact form (by less number of coefficients) compared to other multi-resolution techniques, this paper uses curvelet transform for enhancement of the retinal vasculature. Matched filtering is then used to intensify the blood vessels' response which is further employed by kernel based fuzzy c-means algorithm that extracts the vessel silhouette from the background through non-linear mapping. For pathological images, in addition to matched filtering, Laplacian of Gaussian filter is also employed to distinguish the step and the ramp like signal from that of vessel structure. To test the efficacy of the proposed method, the algorithm has also been applied to images in presence of additive white Gaussian noise where the curvelet transform has been used for image denoising. Performance is evaluated on publicly available DRIVE, STARE and DIARETDB1 databases and is compared with the large number of existing blood vessel extraction methodologies. Simulation results demonstrate that the proposed method is very much efficient in detecting the long and the thick as well as the short and the thin vessels with an average accuracy of 96.16% for the DRIVE and 97.35% for the STARE database wherein the existing methods fail to extract the tiny and the thin vessels. PMID:26848729

  10. Tissue engineering of blood vessels with endothelial cells differentiated from mouse embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    ZHEN XU; MIN XIONG SHEN; DONG ZHU MA; LI YING WANG; XI LIANG ZHA

    2003-01-01

    Endothelial cells (TEC3 cells) derived from mouse embryonic stem (ES) cells were used as seed cells to construct blood vessels. Tissue engineered blood vessels were made by seeding 8 × l06 smooth muscle cells (SMCs) obtained from rabbit arteries onto a sheet of nonwoven polyglycolic acid (PGA) fibers, which was used as a biodegradable polymer scaffold. After being cultured in DMEM medium for 7 days in vitro, SMCs grew well on the PGA fibers, and the cell-PGA sheet was then wrapped around a silicon tube, and implanted subcutaneously into nude mice. After 6~8 weeks, the silicon tube was replaced with another silicon tube in smaller diameter, and then the TEC3 cells (endothelial cells differentiated from mouse ES cells) were injected inside the engineered vessel tube as the test group. In the control group only culture medium was injected. Five days later, the engineered vessels were harvested for gross observation, histological and immunohistochemical analysis. The preliminary results demonstrated that the SMC-PGA construct could form a tubular structure in 6~8 weeks and PGA fibers were completely degraded. Histological and immunohistochemical analysis of the newly formed tissue revealed a typical blood vessel structure, including a lining of endothelial cells (ECs) on the lumimal surface and the presence of SMC and collagen in the wall. No EC lining was found in the tubes of control group. Therefore, the ECs differentiated from mouse ES cells can serve as seed cells for endothelium lining in tissue engineered blood vessels.

  11. Prevent Diabetes Problems: Keep Your Heart and Blood Vessels Healthy

    Science.gov (United States)

    ... Research Training & Career Development Grant programs for students, postdocs, and faculty Research at NIDDK Labs, faculty, and ... Top ] What can I do to prevent or control PAD? Don't smoke. Keep blood glucose and ...

  12. Prevent Diabetes Problems: Keep Your Heart and Blood Vessels Healthy

    Science.gov (United States)

    ... Association of Diabetes Educators Academy of Nutrition and Dietetics National Heart Lung and Blood Institute American Diabetes ... for Scientists Current Funding Opportunities Funded Grants & Grant History Funding Process Research Programs & Contacts Research Training & Career ...

  13. Lymphatic vessels growing apart from blood vessels in transplanted corneas after the blockade of vascular endothelial growth factor C

    Institute of Scientific and Technical Information of China (English)

    Ye Hui; Yan Hao; Zhong Lei; Wang Tao; Deng Juan; Ling Shi-qi

    2016-01-01

    BACKGROUND:Corneal lymphangiogenesis is beneficial to the transport of corneal antigenic materials, and accelerates the process of antigen presentation, thereby playing an important role in corneal immunity. However, due to the paral el outgrowth of corneal blood and lymphatic vessels in transplanted corneas, it is often difficult to accurately evaluate the role of corneal lymphatic vessels in allograft rejection. OBJECTIVE:To explore the development of corneal lymphangiogenesis and angiogenesis in transplanted rat corneas after the blockade of vascular endothelial growth factor C (VEGF-C). METHODS:130 rats used to establish corneal al ogenic transplantation models were equally randomized into two groups:the anti-VEGF-C group and the control group. VEGF-C was blocked in the anti-VEGF-C group by intraperitoneal injection of neutralizing monoclonal anti-VEGF-C antibody every other day for 2 consecutive weeks. Meanwhile, rats in control groups received intraperitoneal injections of saline. Corneal angiogenesis and lymphangiogenesis were characterized using whole mount immunofluorescence, and the immune rejection of the grafts was evaluated by scoring the rejection index (RI). In addition, the expression of VEGF-C was examined by real-time PCR. The relationship of corneal lymphangiogenesis and angiogenesis to RI in transplanted corneas was also characterized. RESULTS AND CONCLUSION:VEGF-C expression was markedly downregulated after VEGF-C blockade. Corneal lymphangiogenesis developed in parallel with corneal angiogenesis in the control group. While there was a mild reduction in blood vessel area (BVA) and a significant decrease in lymphatic vessel area (LVA) in the anti-VEGF-C group (P0.05). the graft survival time in the anti-VEGF-C group was significantly increased compared with that in the control group (P<0.05). Our results show that the outgrowth of lymphatic vessels is separated from that of blood vessels in transplanted corneas by blocking VEGF-C. The blockade

  14. Proliferation of CD8-positive T cells in blood vessels of rat renal allografts.

    Science.gov (United States)

    Grau, V; Fuchs-Moll, G; Wilker, S; Weimer, R; Padberg, W

    2011-09-01

    It is still disputed in which anatomical compartments of allograft recipients T-cells proliferate. After experimental renal transplantation, host monocytes and lymphocytes accumulate in the lumina of graft blood vessels. In this study, we test the hypothesis that T lymphocytes proliferate in the vascular bed of the graft. Kidneys were transplanted in the Dark Agouti to Lewis rat strain combination, an established experimental model for acute rejection. Isogeneic transplantation was performed as a control. Cells in the S-phase of mitosis were detected in situ three days posttransplantation by pulse-labeling with BrdU and by immunohistochemical detection of the proliferating cell nuclear antigen (PCNA). More than 20% of all T-cells in the lumina of allograft blood vessels incorporated BrdU and approximately 30% of them expressed PCNA. In the blood vessels of isografts as well as in other organs of allograft recipients, only few BrdU(+) cells were detected. A majority of the BrdU(+) cells in graft blood vessels expressed CD8. In conclusion, we demonstrate that CD8(+) T lymphocytes proliferate in the lumina of the blood vessels of renal allografts during the onset of acute rejection.

  15. Angioblast Derived from ES Cells Construct Blood Vessels and Ameliorate Diabetic Polyneuropathy in Mice

    Directory of Open Access Journals (Sweden)

    Tatsuhito Himeno

    2015-01-01

    Full Text Available Background. Although numerous reports addressing pathological involvements of diabetic polyneuropathy have been conducted, a universally effective treatment of diabetic polyneuropathy has not yet been established. Recently, regenerative medicine studies in diabetic polyneuropathy using somatic stem/progenitor cell have been reported. However, the effectiveness of these cell transplantations was restricted because of their functional and numerical impairment in diabetic objects. Here, we investigated the efficacy of treatment for diabetic polyneuropathy using angioblast-like cells derived from mouse embryonic stem cells. Methods and Results. Angioblast-like cells were obtained from mouse embryonic stem cells and transplantation of these cells improved several physiological impairments in diabetic polyneuropathy: hypoalgesia, delayed nerve conduction velocities, and reduced blood flow in sciatic nerve and plantar skin. Furthermore, pathologically, the capillary number to muscle fiber ratios were increased in skeletal muscles of transplanted hindlimbs, and intraepidermal nerve fiber densities were ameliorated in transplanted plantar skin. Transplanted cells maintained their viabilities and differentiated to endothelial cells and smooth muscle cells around the injection sites. Moreover, several transplanted cells constructed chimeric blood vessels with recipient cells. Conclusions. These results suggest that transplantation of angioblast like cells induced from embryonic stem cells appears to be a novel therapeutic strategy for diabetic polyneuropathy.

  16. Collagen-based scaffolds for tissue engineering of small-diameter blood vessels

    OpenAIRE

    Buttafoco, Laura

    2005-01-01

    Atherosclerotic vascular disease, including peripheral and coronary artery disease, is the main cause of morbidity and mortality in the Western society. Although synthetic blood vessel prostheses are successfully being used for large-diameter vascular reconstructions, until now no functional small-diameter (< 6 mm) artificial vascular graft is available. Autologous veins and arteries are currently being used as vessel substitutes, but limitations in arteries supply and compliance mismatch are...

  17. Aging changes in the heart and blood vessels

    Science.gov (United States)

    ... for treating high blood pressure, high cholesterol or diabetes. Reduce or stop smoking. Men between the ages of 65 to 75 who have ever smoked should be screened for aneurysms in their abdominal aorta. Get more exercise: Exercise may help prevent obesity, ...

  18. ANALYSIS OF OSCILLATORY BLOOD FLOW IN VARYING-AREA ELASTIC VESSEL

    Institute of Scientific and Technical Information of China (English)

    Gong Ke-qin; Sun Hui; Liu Zhao-rong

    2003-01-01

    In this paper, by solving the fundamental equations of periodically oscillatory blood flow, the distributions of pressure gradient and blood velocity in varying-area elastic vessel were obtained, and then the wall shear stress and its gradient were calculated. As an example, the pulsatile blood flow in human carotid was analyzed and the effects of vessel taper angle on the distribution of wall shear stress and its gradient were discussed in detail. Numercial results show that the wall shear stress will enlarge when the taper angle increases. Meantime, no matter whether the vessel is converging or diverging, with the increase of the absolute value of taper angle, the amplitude of wall shear stress gradient will enlarge significantly.

  19. Mathematical modelling for trajectories of magnetic nanoparticles in a blood vessel under magnetic field

    International Nuclear Information System (INIS)

    A mathematical model is developed to describe the trajectories of a cluster of magnetic nanoparticles in a blood vessel for the application of magnetic drug targeting (MDT). The magnetic nanoparticles are injected into a blood vessel upstream from a malignant tissue and are captured at the tumour site with help of an applied magnetic field. The applied field is produced by a rare earth cylindrical magnet positioned outside the body. All forces expected to significantly affect the transport of nanoparticles were incorporated, including magnetization force, drag force and buoyancy force. The results show that particles are slow down and captured under the influence of magnetic force, which is responsible to attract the magnetic particles towards the magnet. It is optimized that all particles are captured either before or at the centre of the magnet (z≤0) when blood vessel is very close proximity to the magnet (d=2.5 cm). However, as the distance between blood vessel and magnet (d) increases (above 4.5 cm), the magnetic nanoparticles particles become free and they flow away down the blood vessel. Further, the present model results are validated by the simulations performed using the finite element based COMSOL software. - Highlights: • A mathematical model is developed to describe the trajectories of magnetic nanoparticles. • The dominant magnetic, drag and buoyancy forces are considered. • All particles are captured when distance between blood vessel and magnet (d) is up to 4.5 cm. • Further increase in d value (above 4.5 cm) results the free movement of magnetic particles

  20. Do haematophagous bugs assess skin surface temperature to detect blood vessels?

    Directory of Open Access Journals (Sweden)

    Raquel A Ferreira

    Full Text Available BACKGROUND: It is known that some blood-sucking insects have the ability to reach vessels under the host skin with their mouthparts to feed blood from inside them. However, the process by which they locate these vessels remains largely unknown. Less than 5% of the skin is occupied by blood vessels and thus, it is not likely that insects rely on a "random search strategy", since it would increase the probability of being killed by their hosts. Indeed, heterogeneities along the skin surface might offer exploitable information for guiding insect's bites. METHODOLOGY/PRINCIPAL FINDINGS: We tested whether the bug Rhodnius prolixus can evaluate temperature discontinuities along the body surface in order to locate vessels before piercing the host skin. When placed over a rabbit ear, the bug's first bites were mostly directed towards the main vessels. When insects were confronted to artificial linear heat sources presenting a temperature gradient against the background, most bites were directly addressed to the warmer linear source, notwithstanding the temperature of both, the source and the background. Finally, tests performed using uni- and bilaterally antennectomized insects revealed that the bilateral integration of thermal inputs from both antennae is necessary for precisely directing bites. CONCLUSIONS/SIGNIFICANCE: R. prolixus may be able to exploit the temperature differences observed over the skin surface to locate blood vessles. Bugs bite the warmest targets regardless of the target/background temperatures, suggesting that they do not bite choosing a preferred temperature, but select temperature discontinuities along the skin. This strategy seems to be an efficient one for finding blood vessels within a wide temperature range, allowing finding them on different hosts, as well as on different areas of the host body. Our study also adds new insight about the use of antennal thermal inputs by blood sucking bugs.

  1. Mathematical modelling for trajectories of magnetic nanoparticles in a blood vessel under magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Shashi, E-mail: shashisharma1984@gmail.com; Katiyar, V.K.; Singh, Uaday

    2015-04-01

    A mathematical model is developed to describe the trajectories of a cluster of magnetic nanoparticles in a blood vessel for the application of magnetic drug targeting (MDT). The magnetic nanoparticles are injected into a blood vessel upstream from a malignant tissue and are captured at the tumour site with help of an applied magnetic field. The applied field is produced by a rare earth cylindrical magnet positioned outside the body. All forces expected to significantly affect the transport of nanoparticles were incorporated, including magnetization force, drag force and buoyancy force. The results show that particles are slow down and captured under the influence of magnetic force, which is responsible to attract the magnetic particles towards the magnet. It is optimized that all particles are captured either before or at the centre of the magnet (z≤0) when blood vessel is very close proximity to the magnet (d=2.5 cm). However, as the distance between blood vessel and magnet (d) increases (above 4.5 cm), the magnetic nanoparticles particles become free and they flow away down the blood vessel. Further, the present model results are validated by the simulations performed using the finite element based COMSOL software. - Highlights: • A mathematical model is developed to describe the trajectories of magnetic nanoparticles. • The dominant magnetic, drag and buoyancy forces are considered. • All particles are captured when distance between blood vessel and magnet (d) is up to 4.5 cm. • Further increase in d value (above 4.5 cm) results the free movement of magnetic particles.

  2. How to explore the effects of sex hormone on blood vessels

    Institute of Scientific and Technical Information of China (English)

    Sun Mei-li; Nie Min; Liu Bing; Du Zhi-jun; Ge Qin-sheng

    2004-01-01

    The risk of cardiovascular disease increases along with aging. There are increasing interests in researches on the protective effects of hormone replacement therapy (HRT)on cardiovascular system in postmenopausal women. In this article we will review how we have explored the evidence of different sex hormones on blood vessels since 1996. The results showed that low-dose HRT significantly protected cardiovascular system in postmenopausal women.However, the high-dose 17β-estradiol (E2), with or without progesterone (P) or testosterone (T), or any hormone alone, as their concentrations increase, may even inhibit the protective effects of low-dose HRT on blood vessels.

  3. Simulation of Blood Flow at Vessel Bifurcation by Lattice Boltzmann Method

    Science.gov (United States)

    Kang, Xiu-Ying; Liu, Da-He; Zhou, Jing; Jin, Yong-Juan

    2005-11-01

    The application of the lattice Boltzmann method to the large vessel bifurcation blood flow is investigated in a wide range of Reynolds numbers. The velocity, shear stress and pressure distributions at the bifurcation are presented in detail. The flow separation zones revealed with increase of Reynolds number are located in the areas of the daughter branches distal to the outer corners of the bifurcation where some deposition of particular blood components might occur to form arteriosclerosis. The results also demonstrate that the lattice Boltzmann method is adaptive to simulating the flow in larger vessels under a high Reynolds number.

  4. Negative Pressure Wound Therapy - Mechanisms of Action and Protecting Exposed Blood Vessels in the Wound Bed

    OpenAIRE

    Anesäter, Erik

    2015-01-01

    NPWT has recently been associated with severe complications and bleeding when used in wounds with exposed blood vessels. The aims of this work were to investigate the mechanisms of action of NPWT and to explore the possibility of using thin plastic discs to protect exposed blood vessels in the wound bed during NPWT. Three different kinds of wounds were created in pigs: 6 cm and 10 cm diameter circular defect wounds on the back and 6 cm incision wounds in the groin, exposing the...

  5. Transient Non-Newtonian Blood Flow under Magnetic Targeting Drug Delivery in an Aneurysm Blood Vessel with Porous Walls

    Science.gov (United States)

    Alimohamadi, Haleh; Imani, Mohsen

    2014-11-01

    The present investigation deals with numerical solution of blood flow patterns through an aneurysm artery under the applied magnetic field. Transient extended Navier-Stokes, Brinkman, continuity, and heat conduction equations govern this phenomenon and unsteady pulsatile inlet velocity varies by human heart-beating frequency. Our simulation demonstrates applying 105 magnetic field intensity (MnF) to recirculate flow and increase fluid flux and maximum blood temperature by 62.5x and 3.5%, respectively, in the aneurysm region. It is also shown that the vessel's wall porosity plays an important role in magnetic targeting of drug delivery performance, as this parameter can noticeably change maximum blood temperature and pressure.

  6. Analyzing isolated blood vessel contraction in multi-well plates.

    Science.gov (United States)

    Borges, Ricardo; Díaz-Martín, David; Hernández-Jiménez, José G; Rodríguez-Valido, Manuel; Beltrán, Beatriz

    2016-05-01

    Organ baths have been successfully used for over a century to study the contractile or relaxation effects of drugs. Indeed, most of our understanding of vascular pharmacology is based on such in vitro studies. However, multiple parallel organ baths that require mechanical transduction consume relatively large amounts of drugs, gases, and buffers, and they take up a considerable bench space. In addition, such experiments have a high demand in terms of cost and animals, and the tissue preparation is labor intensive and slow. For these reasons, organ baths are no longer in the front line of industrial pharmacological research and they have almost disappeared from most academic laboratories. We have developed a very simple system, which can be implemented virtually in any laboratory, for the automatic analyses of rat aorta ring contraction based on optical methods and using multi-well plates. Rat aorta rings (≈0.5 mm wide) were situated in 96-multi-well plates, and the luminal vessel areas were continuously monitored using a USB camera driven by newly developed algorithms. Liquids were handled using multichannel pipettes, although these procedures can be automated for drug screening. The concentration-response curves obtained were similar to those reported in the literature using traditional force transduction techniques on isolated tissues. This system can also be used with other tissue preparations and for simultaneous fluorescence measurements. The new system described here offers a simple, cheap, and reliable alternative to the classic organ bath system.

  7. Contact-inhibited chemotaxis in de novo and sprouting blood-vessel growth.

    Directory of Open Access Journals (Sweden)

    Roeland M H Merks

    Full Text Available Blood vessels form either when dispersed endothelial cells (the cells lining the inner walls of fully formed blood vessels organize into a vessel network (vasculogenesis, or by sprouting or splitting of existing blood vessels (angiogenesis. Although they are closely related biologically, no current model explains both phenomena with a single biophysical mechanism. Most computational models describe sprouting at the level of the blood vessel, ignoring how cell behavior drives branch splitting during sprouting. We present a cell-based, Glazier-Graner-Hogeweg model (also called Cellular Potts Model simulation of the initial patterning before the vascular cords form lumens, based on plausible behaviors of endothelial cells. The endothelial cells secrete a chemoattractant, which attracts other endothelial cells. As in the classic Keller-Segel model, chemotaxis by itself causes cells to aggregate into isolated clusters. However, including experimentally observed VE-cadherin-mediated contact inhibition of chemotaxis in the simulation causes randomly distributed cells to organize into networks and cell aggregates to sprout, reproducing aspects of both de novo and sprouting blood-vessel growth. We discuss two branching instabilities responsible for our results. Cells at the surfaces of cell clusters attempting to migrate to the centers of the clusters produce a buckling instability. In a model variant that eliminates the surface-normal force, a dissipative mechanism drives sprouting, with the secreted chemical acting both as a chemoattractant and as an inhibitor of pseudopod extension. Both mechanisms would also apply if force transmission through the extracellular matrix rather than chemical signaling mediated cell-cell interactions. The branching instabilities responsible for our results, which result from contact inhibition of chemotaxis, are both generic developmental mechanisms and interesting examples of unusual patterning instabilities.

  8. Mouse lung contains endothelial progenitors with high capacity to form blood and lymphatic vessels

    Directory of Open Access Journals (Sweden)

    Barleon Bernhard

    2010-07-01

    Full Text Available Abstract Background Postnatal endothelial progenitor cells (EPCs have been successfully isolated from whole bone marrow, blood and the walls of conduit vessels. They can, therefore, be classified into circulating and resident progenitor cells. The differentiation capacity of resident lung endothelial progenitor cells from mouse has not been evaluated. Results In an attempt to isolate differentiated mature endothelial cells from mouse lung we found that the lung contains EPCs with a high vasculogenic capacity and capability of de novo vasculogenesis for blood and lymph vessels. Mouse lung microvascular endothelial cells (MLMVECs were isolated by selection of CD31+ cells. Whereas the majority of the CD31+ cells did not divide, some scattered cells started to proliferate giving rise to large colonies (> 3000 cells/colony. These highly dividing cells possess the capacity to integrate into various types of vessels including blood and lymph vessels unveiling the existence of local microvascular endothelial progenitor cells (LMEPCs in adult mouse lung. EPCs could be amplified > passage 30 and still expressed panendothelial markers as well as the progenitor cell antigens, but not antigens for immune cells and hematopoietic stem cells. A high percentage of these cells are also positive for Lyve1, Prox1, podoplanin and VEGFR-3 indicating that a considerabe fraction of the cells are committed to develop lymphatic endothelium. Clonogenic highly proliferating cells from limiting dilution assays were also bipotent. Combined in vitro and in vivo spheroid and matrigel assays revealed that these EPCs exhibit vasculogenic capacity by forming functional blood and lymph vessels. Conclusion The lung contains large numbers of EPCs that display commitment for both types of vessels, suggesting that lung blood and lymphatic endothelial cells are derived from a single progenitor cell.

  9. The role of blood vessels in high-resolution volume conductor head modeling of EEG.

    Science.gov (United States)

    Fiederer, L D J; Vorwerk, J; Lucka, F; Dannhauer, M; Yang, S; Dümpelmann, M; Schulze-Bonhage, A; Aertsen, A; Speck, O; Wolters, C H; Ball, T

    2016-03-01

    Reconstruction of the electrical sources of human EEG activity at high spatio-temporal accuracy is an important aim in neuroscience and neurological diagnostics. Over the last decades, numerous studies have demonstrated that realistic modeling of head anatomy improves the accuracy of source reconstruction of EEG signals. For example, including a cerebro-spinal fluid compartment and the anisotropy of white matter electrical conductivity were both shown to significantly reduce modeling errors. Here, we for the first time quantify the role of detailed reconstructions of the cerebral blood vessels in volume conductor head modeling for EEG. To study the role of the highly arborized cerebral blood vessels, we created a submillimeter head model based on ultra-high-field-strength (7T) structural MRI datasets. Blood vessels (arteries and emissary/intraosseous veins) were segmented using Frangi multi-scale vesselness filtering. The final head model consisted of a geometry-adapted cubic mesh with over 17×10(6) nodes. We solved the forward model using a finite-element-method (FEM) transfer matrix approach, which allowed reducing computation times substantially and quantified the importance of the blood vessel compartment by computing forward and inverse errors resulting from ignoring the blood vessels. Our results show that ignoring emissary veins piercing the skull leads to focal localization errors of approx. 5 to 15mm. Large errors (>2cm) were observed due to the carotid arteries and the dense arterial vasculature in areas such as in the insula or in the medial temporal lobe. Thus, in such predisposed areas, errors caused by neglecting blood vessels can reach similar magnitudes as those previously reported for neglecting white matter anisotropy, the CSF or the dura - structures which are generally considered important components of realistic EEG head models. Our findings thus imply that including a realistic blood vessel compartment in EEG head models will be helpful to

  10. Peristaltic Pumping of Blood Through Small Vessels of Varying Cross-Section

    Science.gov (United States)

    Misra, J. C.; Maiti, S.

    2012-11-01

    The paper is devoted to a study of the peristaltic motion of blood in the micro-circulatory system. The vessel is considered to be of varying cross-section. The progressive peristaltic waves are taken to be of sinusoidal nature. Blood is considered to be a Herschel-Bulkley fluid. Of particular concern here is to investigate the effects of amplitude ratio, mean pressure gradient, yield stress and the power law index on the velocity distribution, streamline pattern and wall shear stress. On the basis of the derived analytical expression, extensive numerical calculations have been made. The study reveals that velocity of blood and wall shear stress are appreciably affected due to the non-uniform geometry of blood vessels. They are also highly sensitive to the magnitude of the amplitude ratio and the value of the fluid index.

  11. Quantification of mast cells and blood vessels in the skin of patients with cutaneous mucinosis.

    Science.gov (United States)

    Martins, Clarice; Nascimento, Adriana Paulino; Monte-Alto-Costa, Andréa; Alves, Maria de Fátima Scotelaro; Carneiro, Sueli Coelho; Porto, Luís Cristóvão de Moraes Sobrino

    2010-07-01

    Recent studies have suggested that mast cell numbers are increased in the skin of patients with cutaneous mucinosis and that these cells may have an important role in angiogenesis and production of mucin. Then, skin biopsies from 30 patients with cutaneous mucinosis (papular mucinosis, focal mucinosis, and mucinosis associated with lupus erythematosus) and from 10 healthy subjects were analyzed. Mast cells and blood vessels were immunolabeled with anti-tryptase and anti-CD34 antibodies, respectively, and then quantified stereologically. Counting was performed in papillary and reticular dermis. An increase in the number of mast cells was observed in the skin of patients with cutaneous mucinosis compared with the control group. Only minimal differences were observed in vessel stereology. There was no correlation between the increase in the number of mast cells and the number of blood vessels in the patients studied. There was no significant difference in the numbers of mast cells or blood vessels between the 3 subgroups of cutaneous mucinosis. Although many clinical forms of mucinosis have been described, neither mast cell number nor vessel distribution seems to distinguish the 3 different forms studied here.

  12. Do double gloves protect against contamination during cannulation of blood vessels? A prospective randomized study

    OpenAIRE

    Łukasz Szarpak; Andrzej Kurowski

    2014-01-01

    Background: Undamaged medical gloves protect medical personnel from contact with physiological fluids of the patient. Thus they protect the assistance provider from hand skin contamination with potentially infectious biological material. The aim of the study was to evaluate the occurrence of pierce, perforations or damage of medical gloves during cannulation of blood vessels. Materials and Methods: In the prospective randomized study 303 pairs of gloves, used during cannulation of blood vesse...

  13. Effect of Loading Densities in Closed Vessel Tests on the Burning Rate of a Propelling Charge

    Directory of Open Access Journals (Sweden)

    Pragati Mehta

    2015-04-01

    Full Text Available Closed vessel firing of gun propellant at different loading densities is conducted for evaluation of its ballistic parameters. Although in actual gun applications, loading densities are higher, but for closed vessel evaluation standard loading density is taken as 0.2 g/cc for interior ballistic calculations of guns. Closed vessel evaluation of standard triple-base propellant in hepta-tubular configuration with loading density varying in the range of 0.2 g/cc to 0.3 g/cc is conducted for the evaluation of salient ballistic parameters. It is observed that maximum pressure increases with increase in loading density of propellants. As loading density increases, rate of rise of pressure also increases. Accordingly, a rise in burning rate is also observed. However, the burning rate index (α and coefficient (β of the power law of burning (r = βPα is found independent of loading density. The average values of these burning rate parameters are calculated as (α = 0.78 and (β = 0.45 for the studied propellant.Defence Science Journal, Vol. 65, No. 2, March 2015, pp.126-130, DOI:http://dx.doi.org/10.14429/dsj.65.8158

  14. In situ tissue engineering of functional small-diameter blood vessels by host circulating cells only

    NARCIS (Netherlands)

    Talacua, Hanna; Smits, Anthal I P M; Muylaert, Dimitri E P; Van Rijswijk, Jan Willem; Vink, Aryan; Verhaar, Marianne C.; Driessen-Mol, Anita; Van Herwerden, Lex A.; Bouten, Carlijn V C; Kluin, Jolanda; Baaijens, Frank P T

    2015-01-01

    Inflammation is a natural phase of the wound healing response, which can be harnessed for the in situ tissue engineering of small-diameter blood vessels using instructive, bioresorbable synthetic grafts. This process is dependent on colonization of the graft by host circulating cells and subsequent

  15. Mass Spectrometry and Antibody-Based Characterization of Blood Vessels from Brachylophosaurus canadensis.

    Science.gov (United States)

    Cleland, Timothy P; Schroeter, Elena R; Zamdborg, Leonid; Zheng, Wenxia; Lee, Ji Eun; Tran, John C; Bern, Marshall; Duncan, Michael B; Lebleu, Valerie S; Ahlf, Dorothy R; Thomas, Paul M; Kalluri, Raghu; Kelleher, Neil L; Schweitzer, Mary H

    2015-12-01

    Structures similar to blood vessels in location, morphology, flexibility, and transparency have been recovered after demineralization of multiple dinosaur cortical bone fragments from multiple specimens, some of which are as old as 80 Ma. These structures were hypothesized to be either endogenous to the bone (i.e., of vascular origin) or the result of biofilm colonizing the empty osteonal network after degradation of original organic components. Here, we test the hypothesis that these structures are endogenous and thus retain proteins in common with extant archosaur blood vessels that can be detected with high-resolution mass spectrometry and confirmed by immunofluorescence. Two lines of evidence support this hypothesis. First, peptide sequencing of Brachylophosaurus canadensis blood vessel extracts is consistent with peptides comprising extant archosaurian blood vessels and is not consistent with a bacterial, cellular slime mold, or fungal origin. Second, proteins identified by mass spectrometry can be localized to the tissues using antibodies specific to these proteins, validating their identity. Data are available via ProteomeXchange with identifier PXD001738. PMID:26595531

  16. Blood Vessel Segmentation Using Moving-Window Robust Automatic Threshold Selection

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.; Wijbenga, Tsjipke; Vries, Gijs de; Westenberg, Michel A.

    2003-01-01

    Two moving-window methods, using either flat or Gaussian weighted windows, for local thresholding with Robust Automatic Threshold Selection are developed. The results show that fast segmentation of blood vessels against a varying background and noise is possible at modest computational cost. Volumes

  17. Transdermal drug targeting and functional imaging of tumor blood vessels in the mouse auricle.

    Science.gov (United States)

    Schröder, Hannes; Komljenovic, Dorde; Hecker, Markus; Korff, Thomas

    2016-02-01

    Subcutaneously growing tumors are widely utilized to study tumor angiogenesis and the efficacy of antiangiogenic therapies in mice. To additionally assess functional and morphologic alterations of the vasculature in the periphery of a growing tumor, we exploited the easily accessible and hierarchically organized vasculature of the mouse auricle. By site-specific subcutaneous implantation of a defined preformed mouse B16/F0 melanoma aggregate, a solid tumor nodule developed within 14 d. Growth of the tumor nodule was accompanied by a 4-fold increase in its perfusion as well as a 2- to 4-fold elevated diameter and perfusion of peripheral blood vessels that had connected to the tumor capillary microvasculature. By transdermal application of the anticancer drug bortezomib, tumor growth was significantly diminished by about 50% without provoking side effects. Moreover, perfusion and tumor microvessel diameter as well as growth and perfusion of arterial or venous blood vessels supplying or draining the tumor microvasculature were decreased under these conditions by up to 80%. Collectively, we observed that the progressive tumor growth is accompanied by the enlargement of supplying and draining extratumoral blood vessels. This process was effectively suppressed by bortezomib, thereby restricting the perfusion capacity of both extra and intratumoral blood vessels. PMID:26546130

  18. Enhanced Bonding Strength of Hydrophobically Modified Gelatin Films on Wet Blood Vessels

    Directory of Open Access Journals (Sweden)

    Keiko Yoshizawa

    2014-01-01

    Full Text Available The bonding behavior between hydrophobically modified alkaline-treated gelatin (hm-AlGltn films and porcine blood vessels was evaluated under wet conditions. Hexanoyl (Hx: C6, decanoyl (Dec: C10, and stearyl (Ste: C18 chlorides were introduced into the amino groups of AlGltn to obtain HxAlGltn, DecAlGltn, and SteAlGltn, respectively, with various modification percentages. The hm-AlGltn was fabricated into films and thermally crosslinked to obtain water-insoluble films (t-hm-AlGltn. The 42% modified t-HxAlGltn (t-42HxAlGltn possessed higher wettability than the 38% modified t-DecAlGltn (t-38DecAlGltn and the 44% modified t-SteAlGltn (t-44SteAlGltn films, and the t-42HxAlGltn film showed a high bonding strength with the blood vessel compared with all the hm-AlGltn films. Histological observations indicated that t-42HxAlGltn and t-38DecAlGltn remained on the blood vessel even after the bonding strength measurements. From cell culture experiments, the t-42HxAlGltn films showed significant cell adhesion compared to other films. These findings indicate that the Hx group easily interpenetrated the surface of blood vessels and effectively enhanced the bonding strength between the films and the tissue.

  19. Formation of an artificial blood vessel: adhesion force measurements with optical tweezers

    Science.gov (United States)

    Knoener, Gregor; Campbell, Julie H.; Heckenberg, Norman R.; Rubinsztein-Dunlop, Halina

    2004-10-01

    We are investigating the formation of a tissue capsule around a foreign body. This tissue capsule can be used as an autologous graft for the replacement of diseased blood vessels or for bypass surgery. The graft is grown in the peritoneal cavity of the recipient and the formation starts with the adhesion of cells to the foreign body. We identify the cell type and measure the adhesion of these cells to foreign materials using optical tweezers. Cell adhesion to macroscopic samples and microspheres is investigated. No difference in the adhesion force was measurable for polyethylene, silicon and Tygon on a scale accessible to optical tweezers. The density of adherent cells was found to vary strongly, being highest on polyethylene. The mean rupture forces for cell-microsphere adhesion ranged from 24 to 39 pN and changed upon preadsorption of bovine serum albumin. For plain microspheres, the highest mean rupture force was found for PMMA, which also showed the highest adhesion probability for the cell-microsphere interaction.

  20. Measurements of Dynamic Viscoelasticity of Poly (vinyl alcohol) Hydrogel for the Development of Blood Vessel Biomodeling

    Science.gov (United States)

    Kosukegawa, Hiroyuki; Mamada, Keisuke; Kuroki, Kanju; Liu, Lei; Inoue, Kosuke; Hayase, Toshiyuki; Ohta, Makoto

    In vitro blood vessel biomodeling with realistic mechanical properties and geometrical structures is helpful for training in surgical procedures, especial those used in endovascular treatment. Poly (vinyl alcohol) hydrogel (PVA-H), which is made of Poly (vinyl alcohol) (PVA) and water, may be useful as a material for blood vessel biomodeling due to its low surface friction resistance and good transparency. In order to simulate the mechanical properties of blood vessels, measurements of mechanical properties of PVA-H were carried out with a dynamic mechanical analyzer, and the storage modulus (G’) and loss modulus (G”) of PVA-H were obtained. PVA-Hs were prepared by the low-temperature crystallization method. They were made of PVA with various concentrations (C) and degrees of polymerization (DP), and made by blending two kinds of PVA having different DP or saponification values (SV). The G’ and G” of PVA-H increased, as the C or DP of PVA increased, or as the proportion of PVA with higher DP or SV increased. These results indicate that it is possible to obtain PVA-H with desirable dynamic viscoelasticity. Furthermore, it is suggested that PVA-H is stable in the temperature range of 0°C to 40°C, indicating that biomodeling made of PVA-H should be available at 37°C, the physiological temperature. The dynamic viscoelasticity of PVA-H obtained was similar to that of the dog blood vessel measured in previous reports. In conclusion, PVA-H is suggested to be useful as a material of blood vessel biomodeling.

  1. Enhanced nestin expression and small blood vessels in human pituitary adenomas.

    Science.gov (United States)

    Perez-Millan, María Inés; Berner, Silvia Inés; Luque, Guillermina María; De Bonis, Cristian; Sevlever, Gustavo; Becu-Villalobos, Damasia; Cristina, Carolina

    2013-09-01

    The role of angiogenesis in human pituitary tumor progression is questioned. Our aim was to characterize the morphologic changes that occur in the vasculature of pituitary adenomas, in correlation with the expression of nestin, a protein found in endothelial cells of newly formed vessels of developing organs. We also evaluated the relation of angiogenic markers and nestin with Ki-67 index. Immunohistochemical studies were performed on paraffin embedded samples of 47 pituitary adenomas and six normal pituitaries. We determined microvessel density (number of CD31+ or CD34+ vessels per square millimetre), vascular area (cumulative area occupied by vessels), average vessel size, and further classified vessels as small ( 100 μm2). We correlated the above parameters with nestin expression and Ki-67 index. Lower vascular area compared to normal tissue was found in adenomas (p vessels than control pituitaries (p controls, so that nestin positive area was significantly higher in tumors. Furthermore, nestin area correlated positively with the % of small vessels. Ki-67 correlated neither with vascular area nor with nestin expression. In human pituitary tumors there was a predominance of small capillaries in correlation with increased expression of the progenitor marker nestin. We suggest that angiogenesis is an active process in these tumors, in spite of their low total vascular area when compared to normal pituitaries.

  2. Peristaltic Pumping of Blood in micro-vessels of Non-uniform Cross-section

    CERN Document Server

    Misra, J C

    2010-01-01

    The paper is devoted to a study of the peristaltic motion of blood in the micro-circulatory system. The vessel is considered of non-uniform cross-section. The progressive peristaltic waves are taken to be of sinusoidal nature. The Reynolds number is considered to be small. Blood is considered to be a Herschel-Bulkley fluid. Of particular concern here is to investigate the effects of amplitude ratio, mean pressure gradient, yield stress and the power law index on the velocity distribution, streamline pattern and wall shear stress. Basing upon the study, extensive numerical calculations has been made. The study reveals that peristaltic pumping as well as velocity and wall shear stress are appreciably affected due to the non-uniform geometry of blood vessels. They are also highly sensitive to the magnitude of the amplitude of the amplitude ratio and the value of the fluid index.

  3. Optics based signal processing methods for intraoperative blood vessel detection and quantification in real time (Conference Presentation)

    Science.gov (United States)

    Chaturvedi, Amal; Shukair, Shetha A.; Le Rolland, Paul; Vijayvergia, Mayank; Subramanian, Hariharan; Gunn, Jonathan W.

    2016-03-01

    Minimally invasive operations require surgeons to make difficult cuts to blood vessels and other tissues with impaired tactile and visual feedback. This leads to inadvertent cuts to blood vessels hidden beneath tissue, causing serious health risks to patients and a non-reimbursable financial burden to hospitals. Intraoperative imaging technologies have been developed, but these expensive systems can be cumbersome and provide only a high-level view of blood vessel networks. In this research, we propose a lean reflectance-based system, comprised of a dual wavelength LED, photodiode, and novel signal processing algorithms for rapid vessel characterization. Since this system takes advantage of the inherent pulsatile light absorption characteristics of blood vessels, no contrast agent is required for its ability to detect the presence of a blood vessel buried deep inside any tissue type (up to a cm) in real time. Once a vessel is detected, the system is able to estimate the distance of the vessel from the probe and the diameter size of the vessel (with a resolution of ~2mm), as well as delineate the type of tissue surrounding the vessel. The system is low-cost, functions in real-time, and could be mounted on already existing surgical tools, such as Kittner dissectors or laparoscopic suction irrigation cannulae. Having been successfully validated ex vivo, this technology will next be tested in a live porcine study and eventually in clinical trials.

  4. On ultrasound-induced microbubble oscillation in a capillary blood vessel and its implications for the blood-brain barrier

    Science.gov (United States)

    Wiedemair, W.; Tuković, Ž.; Jasak, H.; Poulikakos, D.; Kurtcuoglu, V.

    2012-02-01

    The complex interaction between an ultrasound-driven microbubble and an enclosing capillary microvessel is investigated by means of a coupled, multi-domain numerical model using the finite volume formulation. This system is of interest in the study of transient blood-brain barrier disruption (BBBD) for drug delivery applications. The compliant vessel structure is incorporated explicitly as a distinct domain described by a dedicated physical model. Red blood cells (RBCs) are taken into account as elastic solids in the blood plasma. We report the temporal and spatial development of transmural pressure (Ptm) and wall shear stress (WSS) at the luminal endothelial interface, both of which are candidates for the yet unknown mediator of BBBD. The explicit introduction of RBCs shapes the Ptm and WSS distributions and their derivatives markedly. While the peak values of these mechanical wall parameters are not affected considerably by the presence of RBCs, a pronounced increase in their spatial gradients is observed compared to a configuration with blood plasma alone. The novelty of our work lies in the explicit treatment of the vessel wall, and in the modelling of blood as a composite fluid, which we show to be relevant for the mechanical processes at the endothelium.

  5. Material-mediated proangiogenic factor release pattern modulates quality of regenerated blood vessels.

    Science.gov (United States)

    Rich, Max H; Lee, Min Kyung; Baek, Kwanghyun; Jeong, Jae Hyun; Kim, Dong Hyun; Millet, Larry J; Bashir, Rashid; Kong, Hyunjoon

    2014-12-28

    Hydrogels designed to sustainably release bioactive molecules are extensively used to enhance tissue repair and regenerative therapies. Along this line, numerous efforts are made to control the molecular release rate and amount. In contrast, few efforts are made to control the molecular release pattern, and, subsequently, modulate the spatial organization of newly forming tissues, including blood vessels. Therefore, using a hydrogel printed to release vascular endothelial growth factor (VEGF) into a pre-defined pattern, this study demonstrates that spatial distribution of VEGF is important in guiding growth direction of new blood vessels, and also in retaining the structural integrity of pre-existing vasculature. Guided by a computational model, we fabricated a patch composed of micro-sized VEGF-releasing poly(ethylene glycol) diacrylate (PEGDA) hydrogel cylinders using an ink-jet printer. Interestingly, hydrogel printed with computationally optimized spacing created anisotropically aligned vasculature exclusively when the printed gel pattern was placed parallel to pre-existing blood vessels. In contrast, vascular sprouting from placing the printed gel pattern perpendicular to pre-existing vessels resulted in deformation and structural disintegration of the original vasculature. We envision that this study will be useful to better understand angiogenesis-modulated neovascularization and further improve the treatment quality for various wounds and tissue defects.

  6. Simulation of Blood Flow at Vessel Bifurcation by Lattice Boltzmann Method

    Institute of Scientific and Technical Information of China (English)

    KANG Xiu-Ying; LIU Da-He; ZHOU Jing; JIN Yong-Juan

    2005-01-01

    @@ The application of the lattice Boltzmann method to the large vessel bifurcation blood flow is investigated in awide range of Reynolds numbers. The velocity, shear stress and pressure distributions at the bifurcation arepresented in detail. The flow separation zones revealed with increase of Reynolds number are located in theareas of the daughter branches distal to the outer corners of the bifurcation where some deposition of particularblood components might occur to form arteriosclerosis. The results also demonstrate that the lattice Boltzmannmethod is adaptive to simulating the flow in larger vessels under a high Reynolds number.

  7. Adaptive ultrasonic measurement of blood vessel diameter and wall thickness: theory and experimental results.

    Science.gov (United States)

    Rafii, K; Jaffe, J S

    1998-01-01

    An adaptive ultrasonic technique for measuring blood vessel diameter and wall thickness is presented. This technique allows one to use a target-specific transmitted waveform/receiver filter to obtain a larger signal-to-noise ratio (SNR) in the received signal than conventional techniques. Generally, SNR of a received wave increases as the intensity of the transmit wave increases; however, because of the FDA limitations placed on the amount of transmit energy, it is important to be able to make the most efficient use of the energy that is available to obtain the best possible SNR in the received signal. Adaptive ultrasonic measurement makes the most efficient use of the energy that is available by placing the maximum amount of energy in the largest target scattering mode. This results in more energy backscatter from a given target, which leads to a higher SNR in the received waveform. Computer simulations of adaptive ultrasonic measurement of blood vessel diameter show that for a SNR of 0 dB in the transmitted waveform, the standard deviation of the diameter measurements for a custom-designed transmitted waveform is about two orders of magnitude less than the standard deviation of the diameter measurements using more conventional waveforms. Diameter and wall thickness measurement experiments were performed on a latex tube and a bovine blood vessel using both custom-made and conventionally used transmitted waveforms. Results show that the adaptively designed waveform gives a smaller uncertainty in the measurements. The adaptive ultrasonic blood vessel diameter and wall thickness measuring technique has potential applications in examining vessels which are either too deep inside the body or too small for conventional techniques to be used, because of the low SNR in the received signal. PMID:18244211

  8. Screening of specific binding peptide targeting blood vessel of human esophageal cancer in vivo in mice

    Institute of Scientific and Technical Information of China (English)

    ZHI Min; WU Kai-chun; HAO Zhi-ming; GUO Chang-cun; YAO Jia-yin

    2011-01-01

    Background Cancer of the esophagus and gastroesophageal junction remains a virulent malignancy with poor prognosis. Rapid progresses were made in chemotherapeutic agents and the development of molecular markers allowed better identification of candidates for targeted therapy. This study aimed to identify the candidate peptides used for anti-angiogenic therapy of esophageal cancer by in vivo screening C7C peptide library for peptides binding specifically to blood vessels of human esophageal cancer.Methods The phage displayed C7C peptide library was injected intravenously into mice bearing human esophageal tumor xenografts under renal capsule. After 5 rounds of screening, 13 clones were picked up individually and sequenced.During each round of screening, titers of phage recovery were calculated from tumor xenograft and control tissues.Homing of these 9 peptides to tumor vessel was detected by calculating phage titers in the tumor xenograft and control tissues (lung and spleen) after each phage was injected into mice model, and compared with the distribution of phage M13 and Ⅷ-related antigen in tumor xenograft by immunohistochemical staining. Comparisons among groups of data were made using one-way analysis of variance (ANOVA), followed by the Bonferroni multiple comparisons test.Results The number of phage recovered from tumor tissue of each round increased gradually in tumor group while decreased in control groups (P <0.01 in tumor and spleen, P <0.05 in lung). Immunohistochemical staining showed similar staining pattern with M13 antibody or Ⅷ-related antigen antibody, suggesting that phages displaying the selected peptides could home to blood vessel of human esophageal cancer. According to their DNA, 9 corresponding peptide sequences were deduced. And the homing ability to blood vessel of phages displaying the selected peptides was confirmed by comparing with their recovery in tumor and control tissues. Two motifs, YSXNXW and PXNXXN, were also obtained by

  9. Threadlike bundle of tubules running inside blood vessels New anatomical structure

    CERN Document Server

    Jiang, X; Shin, H; Lee, B; Choi, C; Soh, K; Cheun, B; Baik, K; Soh, K; Jiang, Xiaowen; Kim, Hee-kyeong; Shin, Hak-soo; Lee, Byong-chon; Choi, Chunho; Soh, Kyung-soon; Cheun, Byeung-soo; Baik, Ku-youn; Soh, Kwang-sup

    2002-01-01

    According to current anatomy, the arteries and veins do not have threadlike structures running inside the vessels. Despite such prevailing knowledge here we report on observation of a novel structure inside the blood vessels of rats and rabbits, which is a semi-transparent elastic bundle of tubules whose diameters are of 10$\\mu$m order. This is a rediscovery of the Bong Han ducts1,2 which have not been confirmed because the observing method was not known. We found a new procedure of observing the intra blood vessel ducts (IBVD) which are too thin, fragile, and semi-transparent to be detected in ordinary surgical operation. The method we contrived is to let blood be coagulated around the IBVD so that they become thick and strong by intravenous injection of 10 per cent dextrose solution at the vena femoralis. A piece of thickened IBVD sample is treated with urokinase to remove blood clots and the thin thread of IBVD is embedded inside of a string of fibrin

  10. Effects of X-irradiation on artificial blood vessel wall degradation by invasive tumor cells

    International Nuclear Information System (INIS)

    Artificial vessel wall cultures, constructed by growing arterial endothelial cells on preformed layers of rat smooth muscle cells, were used to evaluate the effects of X-irradiation on tumor cell-induced tissue degradation. Bovine endothelial cells had radiation sensitivities similar to those of rat smooth muscle cells. Preirradiation of smooth muscle cells, before the addition of human fibrosarcoma (HT 1080) cells, did not increase the rate of degradation and destruction by the invasive cells. However, the degradation rate was decreased if the cultures were irradiated after the addition of HT 1080 cells. The presence of bovine endothelial cells markedly inhibited the destructive abilities of fibrosarcoma cells, but preirradiation of artificial vessel walls substantially decreased their capabilities to resist HT 1080-induced lysis. These findings suggest that the abilities of blood vessels to limit extravasation may be compromised by ionizing radiation

  11. Retinal hemodynamic oxygen reactivity assessed by perfusion velocity, blood oximetry and vessel diameter measurements

    DEFF Research Database (Denmark)

    Klefter, Oliver Niels; Lauritsen, Anne Øberg; Larsen, Michael

    2015-01-01

    PURPOSE: To test the oxygen reactivity of a fundus photographic method of measuring macular perfusion velocity and to integrate macular perfusion velocities with measurements of retinal vessel diameters and blood oxygen saturation. METHODS: Sixteen eyes in 16 healthy volunteers were studied at two...... examination sessions using motion-contrast velocimetry and retinal oximetry with vessel diameter corrections. To test oxygen reactivity, participants were examined during normoxia, after 15 min of hyperoxia and finally after 45 min of normoxia. Repeatability was assessed by intraclass correlation coefficients...... retinal arterial oxygen saturation from 95.1 ± 5.0% to 96.6 ± 6.4% (p = 0.038) and increased retinal venous oxygen saturation from 62.9 ± 6.7% to 70.3 ± 7.8% (p = 0.0010). Parameters returned to baseline levels after subsequent normoxia. Saturation and vessel diameter ICCs were 0.88-0.98 (range...

  12. Blood vessel crosstalk during organogenesis-focus on pancreas and endothelial cells.

    Science.gov (United States)

    Azizoglu, D Berfin; Cleaver, Ondine

    2016-09-01

    Blood vessels form a highly branched, interconnected, and largely stereotyped network of tubes that sustains every organ and tissue in vertebrates. How vessels come to take on their particular architecture, or how they are 'patterned,' and in turn, how they influence surrounding tissues are fundamental questions of organogenesis. Decades of work have begun to elucidate how endothelial progenitors arise and home to precise locations within tissues, integrating attractive and repulsive cues to build vessels where they are needed. Conversely, more recent findings have revealed an exciting facet of blood vessel interaction with tissues, where vascular cells provide signals to developing organs and progenitors therein. Here, we discuss the exchange of reciprocal signals between endothelial cells and neighboring tissues during embryogenesis, with a special focus on the developing pancreas. Understanding the mechanisms driving both sides of these interactions will be crucial to the development of therapies, from improving organ regeneration to efficient production of cell based therapies. Specifically, elucidating the interface of the vasculature with pancreatic lineages, including endocrine cells, will instruct approaches such as generation of replacement beta cells for Type I diabetes. WIREs Dev Biol 2016, 5:598-617. doi: 10.1002/wdev.240 For further resources related to this article, please visit the WIREs website. PMID:27328421

  13. Angiopoietin-4 increases permeability of blood vessels and promotes lymphatic dilation.

    Science.gov (United States)

    Kesler, Cristina T; Pereira, Ethel R; Cui, Cheryl H; Nelson, Gregory M; Masuck, David J; Baish, James W; Padera, Timothy P

    2015-09-01

    The angiopoietin (Ang) ligands are potential therapeutic targets for lymphatic related diseases, which include lymphedema and cancer. Ang-1 and Ang-2 functions are established, but those of Ang-4 are poorly understood. We used intravital fluorescence microscopy to characterize Ang-4 actions on T241 murine fibrosarcoma-associated vessels in mice. The diameters of lymphatic vessels draining Ang-4- or VEGF-C (positive control)-expressing tumors increased to 123 and 135 μm, respectively, and parental, mock-transduced (negative controls) and tumors expressing Ang-1 or Ang-2 remained at baseline (∼60 μm). Ang-4 decreased human dermal lymphatic endothelial cell (LEC) monolayer permeability by 27% while increasing human dermal blood endothelial cell (BEC) monolayer permeability by 200%. In vivo, Ang-4 stimulated a 4.5-fold increase in tumor-associated blood vessel permeability compared with control when measured using intravital quantitative multiphoton microscopy. Ang-4 activated receptor signaling in both LECs and BECs, evidenced by tyrosine kinase with Ig and endothelial growth factor homology domains-2 (TIE2) receptor, protein kinase B, and Erk1,2 phosphorylation detectable by immunoblotting. These data suggest that Ang-4 actions are mediated through cell-type-specific networks and that lymphatic vessel dilation occurs secondarily to increased vascular leakage. Ang-4 also promoted survival of LECs. Thus, blocking Ang-4 may prune the draining lymphatic vasculature and decrease interstitial fluid pressure (IFP) by reducing vascular permeability. PMID:25977256

  14. The Emergence of Blood and Blood Vessels in the Embryo and Its Relevance to Postnatal Biology and Disease

    Science.gov (United States)

    Sills, Tiffany M.; Hirschi, Karen K.

    Blood and blood vessels develop in parallel within mammalian systems, and this temporal and spatial association has led to the confirmation of an endothelial origin of hematopoiesis. The extraembryonic yolk sac and aorto-gonado-mesonephros (AGM) region both contain a specialized population of endothelial cells ("hemogenic endothelium") that function to produce hematopoietic stem and progenitor cells, which then differentiate to provide the full complement of blood cells within the developing embryo and furthermore in the adult system. Therefore, this population has great therapeutic potential in the fields of regenerative medicine and tissue engineering. This chapter reviews the development of the vascular and hematopoietic systems, characterization and function of the hemogenic endothelium within embryonic and embryonic stem cell (ES cell) models, and speculate on the presence of such a population within the adult system. In order to harness this endothelial subtype for clinical application, we must understand both the normal functions of these cells and the potential for misregulation in disease states.

  15. Tight junction between endothelial cells: the interaction between nanoparticles and blood vessels.

    Science.gov (United States)

    Zhang, Yue; Yang, Wan-Xi

    2016-01-01

    Since nanoparticles are now widely applied as food additives, in cosmetics and other industries, especially in medical therapy and diagnosis, we ask here whether nanoparticles can cause several adverse effects to human health. In this review, based on research on nanotoxicity, we mainly discuss the negative influence of nanoparticles on blood vessels in several aspects and the potential mechanism for nanoparticles to penetrate endothelial layers of blood vessels, which are the sites of phosphorylation of tight junction proteins (claudins, occludins, and ZO (Zonula occludens)) proteins, oxidative stress and shear stress. We propose a connection between the presence of nanoparticles and the regulation of the tight junction, which might be the key approach for nanoparticles to penetrate endothelial layers and then have an impact on other tissues and organs. PMID:27335757

  16. Tight junction between endothelial cells: the interaction between nanoparticles and blood vessels

    Science.gov (United States)

    Zhang, Yue

    2016-01-01

    Summary Since nanoparticles are now widely applied as food additives, in cosmetics and other industries, especially in medical therapy and diagnosis, we ask here whether nanoparticles can cause several adverse effects to human health. In this review, based on research on nanotoxicity, we mainly discuss the negative influence of nanoparticles on blood vessels in several aspects and the potential mechanism for nanoparticles to penetrate endothelial layers of blood vessels, which are the sites of phosphorylation of tight junction proteins (claudins, occludins, and ZO (Zonula occludens)) proteins, oxidative stress and shear stress. We propose a connection between the presence of nanoparticles and the regulation of the tight junction, which might be the key approach for nanoparticles to penetrate endothelial layers and then have an impact on other tissues and organs. PMID:27335757

  17. Regulation of monocyte cell fate by blood vessels mediated by Notch signalling.

    Science.gov (United States)

    Gamrekelashvili, Jaba; Giagnorio, Roberto; Jussofie, Jasmin; Soehnlein, Oliver; Duchene, Johan; Briseño, Carlos G; Ramasamy, Saravana K; Krishnasamy, Kashyap; Limbourg, Anne; Kapanadze, Tamar; Ishifune, Chieko; Hinkel, Rabea; Radtke, Freddy; Strobl, Lothar J; Zimber-Strobl, Ursula; Napp, L Christian; Bauersachs, Johann; Haller, Hermann; Yasutomo, Koji; Kupatt, Christian; Murphy, Kenneth M; Adams, Ralf H; Weber, Christian; Limbourg, Florian P

    2016-08-31

    A population of monocytes, known as Ly6C(lo) monocytes, patrol blood vessels by crawling along the vascular endothelium. Here we show that endothelial cells control their origin through Notch signalling. Using combinations of conditional genetic deletion strategies and cell-fate tracking experiments we show that Notch2 regulates conversion of Ly6C(hi) monocytes into Ly6C(lo) monocytes in vivo and in vitro, thereby regulating monocyte cell fate under steady-state conditions. This process is controlled by Notch ligand delta-like 1 (Dll1) expressed by a population of endothelial cells that constitute distinct vascular niches in the bone marrow and spleen in vivo, while culture on recombinant DLL1 induces monocyte conversion in vitro. Thus, blood vessels regulate monocyte conversion, a form of committed myeloid cell fate regulation.

  18. In Vivo μPIV Measurements of Blood Flow in Small Vessels of a Rat Model.

    Science.gov (United States)

    Wei, Timothy; Conner, Nadine; Russell, John; Legac, Paul

    2007-11-01

    Ongoing research at the University of Wisconsin Medical School is addressing the effects of perfusion of glottal tissue on voice production. Building on the approach developed by Gharib's group at CalTech for embryonic zebra fish, we have modified μPIV to measure flow in capillaries and small blood vessels in a live rat model. In lieu of seeding particles, the DPIV correlation algorithm tracks the motion of red blood cells moving through these vessels. The methodology will be presented along with a video sequence showing measurements made from muscle tissue laid nominally flat on a microscope stage. Challenges of measurements in three-dimensional geometries, i.e. the throat, will be discussed.

  19. Blood vessel staining in the myocardium for 3D visualization down to the smallest capillaries

    International Nuclear Information System (INIS)

    Blood vessels formed after medical interventions such as radiofrequency treatment have to be visualized down to the capillary level with diameters of about 5 μm to validate neo-vascularization. Synchrotron radiation-based micro-computed tomography (SRμCT) provides the necessary spatial resolution. Since both the vessels and the surrounding tissue mainly consist of water the difference in absorption is extremely weak. Therefore, it is necessary to search for appropriate contrast agents and to develop suitable staining protocols, which finally allow segmenting the vessel tree. Among the contrast agents used in medicine lyophilic salts with a mean particle diameter of 1.5 μm such as CaSO4, SrSO4 and BaSO4 are most appropriate to stain the vessels. The combination of these salts with a commercially available embedding kit (JB-4, Polysciences Inc.) allows tissue fixation and long-term storage in solid state. Intensity-based segmentation algorithms enable the vessel tree extraction in selected parts of the stained myocardium using the SRμCT data

  20. An Automatic Cognitive Graph-Based Segmentation for Detection of Blood Vessels in Retinal Images

    Directory of Open Access Journals (Sweden)

    Rasha Al Shehhi

    2016-01-01

    Full Text Available This paper presents a hierarchical graph-based segmentation for blood vessel detection in digital retinal images. This segmentation employs some of perceptual Gestalt principles: similarity, closure, continuity, and proximity to merge segments into coherent connected vessel-like patterns. The integration of Gestalt principles is based on object-based features (e.g., color and black top-hat (BTH morphology and context and graph-analysis algorithms (e.g., Dijkstra path. The segmentation framework consists of two main steps: preprocessing and multiscale graph-based segmentation. Preprocessing is to enhance lighting condition, due to low illumination contrast, and to construct necessary features to enhance vessel structure due to sensitivity of vessel patterns to multiscale/multiorientation structure. Graph-based segmentation is to decrease computational processing required for region of interest into most semantic objects. The segmentation was evaluated on three publicly available datasets. Experimental results show that preprocessing stage achieves better results compared to state-of-the-art enhancement methods. The performance of the proposed graph-based segmentation is found to be consistent and comparable to other existing methods, with improved capability of detecting small/thin vessels.

  1. Surface modification of cellulose materials : from wood pulps to artificial blood vessels

    OpenAIRE

    Ahrenstedt, Lage

    2007-01-01

    This thesis describes the improvement of two radically different cellulose materials, paper and artificial blood vessels, constructed from two diverse cellulose sources, wood pulp and Acetobacter xylinum. The improvement of both materials was possible due to the natural affinity of the hemicellulose xyloglucan for cellulose. Chemical and mechanical pulps were treated with xyloglucan in the wet-end prior to hand sheet formation or by spray application of dry hand sheets, loading a comparable a...

  2. Segmentation of retinal blood vessels using normalized Gabor filters and automatic thresholding

    OpenAIRE

    Mandlenkosi Victor Gwetu; Jules Raymond Tapamo; Serestina Viriri

    2014-01-01

    Although computerized retinal image blood vessel segmentation has been extensively researched, there is still room for improvement in the quality of the segmented images. Since retinal image analysis is still widely used in the diagnosis of diabetic retinopathy, efficient and accurate image characterization techniques are required. Previous work has mainly focused on improving segmentation accuracy rates with little regard to the false positives that are produced by illumination variation. T...

  3. Blood vessels and desmin control the positioning of nuclei in skeletal muscle fibers

    DEFF Research Database (Denmark)

    Ralston, E; Lu, Z; Biscocho, N;

    2006-01-01

    . Here we show that the nuclei are preferentially localized near blood vessels (BV), particularly in slow-twitch, oxidative fibers. Thus, in rat soleus muscle fibers, 81% of the nuclei appear next to BV. Lack of desmin markedly perturbs the distribution of nuclei along the fibers but does not prevent....... We conclude that the positioning of nuclei along muscle fibers is plastic and that BV and desmin intermediate filaments each play a distinct role in the control of this positioning....

  4. Simulation of Molecular Signaling in Blood Vessels: Software Design and Application to Atherogenesis

    OpenAIRE

    Felicetti, Luca; Femminella, Mauro; Reali, Gianluca

    2013-01-01

    This paper presents a software platform, named BiNS2, able to simulate diffusion-based molecular communications with drift inside blood vessels. The contribution of the paper is twofold. First a detailed description of the simulator is given, under the software engineering point of view, by highlighting the innovations and optimizations introduced. Their introduction into the previous version of the BiNS simulator was needed to provide to functions for simulating molecular signaling and commu...

  5. Ectopic fat storage in heart, blood vessels and kidneys in the pathogenesis of cardiovascular diseases

    OpenAIRE

    Montani, Jean-Pierre; Carroll, Joan F; Dwyer, Terry M.; Antic, Vladan; Yang, Zhihong; Abdul G Dulloo

    2005-01-01

    In humans and most animal models, the development of obesity leads not only to increased fat depots in classical adipose tissue locations but also to significant lipid deposits within and around other tissues and organs, a phenomenon known as ectopic fat storage. The purpose of this review is to explore the possible locations of ectopic fat in key target-organs of cardiovascular control (heart, blood vessels and kidneys) and to propose how ectopic fat storage can play a role in the pathogenes...

  6. Automatic segmentation of blood vessels from MR angiography volume data by using fuzzy logic technique

    Science.gov (United States)

    Kobashi, Syoji; Hata, Yutaka; Tokimoto, Yasuhiro; Ishikawa, Makato

    1999-05-01

    This paper shows a novel medical image segmentation method applied to blood vessel segmentation from magnetic resonance angiography volume data. The principle idea of the method is fuzzy information granulation concept. The method consists of 2 parts: (1) quantization and feature extraction, (2) iterative fuzzy synthesis. In the first part, volume quantization is performed with watershed segmentation technique. Each quantum is represented by three features, vascularity, narrowness and histogram consistency. Using these features, we estimate the fuzzy degrees of each quantum for knowledge models about MRA volume data. In the second part, the method increases the fuzzy degrees by selectively synthesizing neighboring quantums. As a result, we obtain some synthesized quantums. We regard them as fuzzy granules and classify them into blood vessel or fat by evaluating the fuzzy degrees. In the experimental result, three dimensional images are generated using target maximum intensity projection (MIP) and surface shaded display. The comparison with conventional MIP images shows that the unclarity region in conventional images are clearly depict in our images. The qualitative evaluation done by a physician shows that our method can extract blood vessel region and that the results are useful to diagnose the cerebral diseases.

  7. Measuring properties of nanoparticles in embryonic blood vessels: Towards a physicochemical basis for nanotoxicity

    Science.gov (United States)

    Clancy, Aisling A.; Gregoriou, Yiota; Yaehne, Kristin; Cramb, David T.

    2010-03-01

    The developing field of nanotoxicology aims to relate the physical properties of nanomaterials to potential risk when organisms are exposed to those materials. Regulators are interested in whether a nanoformulation would alter the risk of the native material. It may be that due to the physical nature of embryonic blood vessels (i.e. they are angiogenic and therefore leaky), embryos are at greater risk for bioaccumulation of nanoparticles (NPs) than mature organisms. To study the physicochemical nature of nanoparticle accumulation from embryonic blood vessels, one needs to measure the NP properties in situ, because these properties could be significantly dependent on environment. We have undertaken a study of the dynamics of CdSe/ZnS quantum dots and polystyrene nanospheres in the blood vessels of the chicken embryo chorioallantoic membrane (CAM). We show proof of principle that fluorescence correlation spectroscopy can be used in this system to determine the concentrations and hydrodynamic radii of NP solutions micro-injected into the CAM.

  8. Sensitivity analysis aimed at blood vessels detection using interstitial optical tomography during brain needle biopsy procedures.

    Science.gov (United States)

    Pichette, Julien; Goyette, Andréanne; Picot, Fabien; Tremblay, Marie-Andrée; Soulez, Gilles; Wilson, Brian C; Leblond, Frédéric

    2015-11-01

    A brain needle biopsy procedure is performed for suspected brain lesions in order to sample tissue that is subsequently analysed using standard histopathology techniques. A common complication resulting from this procedure is brain hemorrhaging from blood vessels clipped off during tissue extraction. Interstitial optical tomography (iOT) has recently been introduced by our group as a mean to assess the presence of blood vessels in the vicinity of the needle. The clinical need to improve safety requires the detection of blood vessels within 2 mm from the outer surface of the needle, since this distance is representative of the volume of tissue that is aspirated durirng tissue extraction. Here, a sensitivity analysis is presented to establish the intrinsic detection limits of iOT based on simulations and experiments using brain tissue phantoms. It is demonstrated that absorbers can be detected with diameters >300 μm located up to >2 mm from the biopsy needle core for bulk optical properties consistent with brain tissue. PMID:26600990

  9. Endovascular Electrodes for Electrical Stimulation of Blood Vessels for Vasoconstriction - a Finite Element Simulation Study.

    Science.gov (United States)

    Kezurer, Noa; Farah, Nairouz; Mandel, Yossi

    2016-01-01

    Hemorrhagic shock accounts for 30-40 percent of trauma mortality, as bleeding may sometimes be hard to control. Application of short electrical pulses on blood vessels was recently shown to elicit robust vasoconstriction and reduction of blood loss following vascular injury. In this study we present a novel approach for vasoconstriction based on endovascular application of electrical pulses for situations where access to the vessel is limited. In addition to ease of access, we hypothesize that this novel approach will result in a localized and efficient vasoconstriction. Using computer modeling (COMSOL Multiphysics, Electric Currents Module), we studied the effect of endovascular pulsed electrical treatment on abdominal aorta of pigs, and compared the efficiency of different electrodes configurations on the electric field amplitude, homogeneity and locality when applied on a blood vessel wall. Results reveal that the optimal configuration is the endovascular approach where four electrodes are used, spaced 13 mm apart. Furthermore, computer based temperature investigations (bio-heat model, COMSOL Multiphysics) show that the maximum expected temperature rise is of 1.2 degrees; highlighting the safety of the four endovascular electrodes configuration. These results can aid in planning the application of endovascular pulsed electrical treatment as an efficient and safe vasoconstriction approach. PMID:27534438

  10. Endovascular Electrodes for Electrical Stimulation of Blood Vessels for Vasoconstriction – a Finite Element Simulation Study

    Science.gov (United States)

    Kezurer, Noa; Farah, Nairouz; Mandel, Yossi

    2016-01-01

    Hemorrhagic shock accounts for 30–40 percent of trauma mortality, as bleeding may sometimes be hard to control. Application of short electrical pulses on blood vessels was recently shown to elicit robust vasoconstriction and reduction of blood loss following vascular injury. In this study we present a novel approach for vasoconstriction based on endovascular application of electrical pulses for situations where access to the vessel is limited. In addition to ease of access, we hypothesize that this novel approach will result in a localized and efficient vasoconstriction. Using computer modeling (COMSOL Multiphysics, Electric Currents Module), we studied the effect of endovascular pulsed electrical treatment on abdominal aorta of pigs, and compared the efficiency of different electrodes configurations on the electric field amplitude, homogeneity and locality when applied on a blood vessel wall. Results reveal that the optimal configuration is the endovascular approach where four electrodes are used, spaced 13 mm apart. Furthermore, computer based temperature investigations (bio-heat model, COMSOL Multiphysics) show that the maximum expected temperature rise is of 1.2 degrees; highlighting the safety of the four endovascular electrodes configuration. These results can aid in planning the application of endovascular pulsed electrical treatment as an efficient and safe vasoconstriction approach. PMID:27534438

  11. Nitric oxide control of lower vertebrate blood vessels by vasomotor nerves.

    Science.gov (United States)

    Donald, John A; Broughton, Brad R S

    2005-10-01

    In mammals, much is understood about the endothelial and neural NO control mechanisms in the vasculature. In contrast, NO control of blood vessels in lower vertebrates is poorly understood, with the majority of research focusing on the presence of an endothelial NO system; however, its presence remains controversial. This study examined the mechanisms by which NO regulates the large blood vessels of non-mammalian vertebrates. In all species examined, the arteries and veins contained a plexus of NOS-positive perivascular nerves that included nerve bundles and fine, varicose nerve terminals. However, in the large arteries and veins of various species of fishes and amphibians, no anatomical evidence was found for endothelial NOS using both NADPH-diaphorase and eNOS immunohistochemistry. In contrast, perinuclear NOS staining was readily apparent in blue-tongue lizard, pigeon and rat, which suggested that eNOS first appeared in reptiles. Physiological analysis of NO signalling in the vascular smooth muscle of short-finned eel and cane toad could not find any evidence for endothelial NO signalling. In contrast, it appears that activation of the nitrergic vasomotor nerves is responsible for NO control of the blood vessels.

  12. Endovascular Electrodes for Electrical Stimulation of Blood Vessels for Vasoconstriction - a Finite Element Simulation Study.

    Science.gov (United States)

    Kezurer, Noa; Farah, Nairouz; Mandel, Yossi

    2016-08-18

    Hemorrhagic shock accounts for 30-40 percent of trauma mortality, as bleeding may sometimes be hard to control. Application of short electrical pulses on blood vessels was recently shown to elicit robust vasoconstriction and reduction of blood loss following vascular injury. In this study we present a novel approach for vasoconstriction based on endovascular application of electrical pulses for situations where access to the vessel is limited. In addition to ease of access, we hypothesize that this novel approach will result in a localized and efficient vasoconstriction. Using computer modeling (COMSOL Multiphysics, Electric Currents Module), we studied the effect of endovascular pulsed electrical treatment on abdominal aorta of pigs, and compared the efficiency of different electrodes configurations on the electric field amplitude, homogeneity and locality when applied on a blood vessel wall. Results reveal that the optimal configuration is the endovascular approach where four electrodes are used, spaced 13 mm apart. Furthermore, computer based temperature investigations (bio-heat model, COMSOL Multiphysics) show that the maximum expected temperature rise is of 1.2 degrees; highlighting the safety of the four endovascular electrodes configuration. These results can aid in planning the application of endovascular pulsed electrical treatment as an efficient and safe vasoconstriction approach.

  13. Do double gloves protect against contamination during cannulation of blood vessels? A prospective randomized study

    Directory of Open Access Journals (Sweden)

    Łukasz Szarpak

    2014-04-01

    Full Text Available Background: Undamaged medical gloves protect medical personnel from contact with physiological fluids of the patient. Thus they protect the assistance provider from hand skin contamination with potentially infectious biological material. The aim of the study was to evaluate the occurrence of pierce, perforations or damage of medical gloves during cannulation of blood vessels. Materials and Methods: In the prospective randomized study 303 pairs of gloves, used during cannulation of blood vessels under simulated resuscitation, were analyzed. Gloves were tested by the water leak test. Results: The water test revealed 44 cases of damage to the gloves used during cannulation of blood vessels. Significant differences were noted in the frequency of damage to both the outer and single pairs of gloves and the inner pair of gloves. Conclusions: The study showed that the use of double gloves provides a higher level of security for a paramedic than the use of a single pair of gloves, however, double gloves reduce the manual dexterity of a paramedic. A large number of damages to gloves are not noticed by medical personnel during surgery. Med Pr 2014;65(2:271–278

  14. Microcirculation-on-a-Chip: A Microfluidic Platform for Assaying Blood- and Lymphatic-Vessel Permeability.

    Directory of Open Access Journals (Sweden)

    Miwa Sato

    Full Text Available We developed a microfluidic model of microcirculation containing both blood and lymphatic vessels for examining vascular permeability. The designed microfluidic device harbors upper and lower channels that are partly aligned and are separated by a porous membrane, and on this membrane, blood vascular endothelial cells (BECs and lymphatic endothelial cells (LECs were cocultured back-to-back. At cell-cell junctions of both BECs and LECs, claudin-5 and VE-cadherin were detected. The permeability coefficient measured here was lower than the value reported for isolated mammalian venules. Moreover, our results showed that the flow culture established in the device promoted the formation of endothelial cell-cell junctions, and that treatment with histamine, an inflammation-promoting substance, induced changes in the localization of tight and adherens junction-associated proteins and an increase in vascular permeability in the microdevice. These findings indicated that both BECs and LECs appeared to retain their functions in the microfluidic coculture platform. Using this microcirculation device, the vascular damage induced by habu snake venom was successfully assayed, and the assay time was reduced from 24 h to 30 min. This is the first report of a microcirculation model in which BECs and LECs were cocultured. Because the micromodel includes lymphatic vessels in addition to blood vessels, the model can be used to evaluate both vascular permeability and lymphatic return rate.

  15. Modeling the Role of the Glymphatic Pathway and Cerebral Blood Vessel Properties in Alzheimer's Disease Pathogenesis.

    Directory of Open Access Journals (Sweden)

    Christina Rose Kyrtsos

    Full Text Available Alzheimer's disease (AD is the most common cause of dementia in the elderly, affecting over 10% population over the age of 65 years. Clinically, AD is described by the symptom set of short term memory loss and cognitive decline, changes in mentation and behavior, and eventually long-term memory deficit as the disease progresses. On imaging studies, significant atrophy with subsequent increase in ventricular volume have been observed. Pathology on post-mortem brain specimens demonstrates the classic findings of increased beta amyloid (Aβ deposition and the presence of neurofibrillary tangles (NFTs within affected neurons. Neuroinflammation, dysregulation of blood-brain barrier transport and clearance, deposition of Aβ in cerebral blood vessels, vascular risk factors such as atherosclerosis and diabetes, and the presence of the apolipoprotein E4 allele have all been identified as playing possible roles in AD pathogenesis. Recent research has demonstrated the importance of the glymphatic system in the clearance of Aβ from the brain via the perivascular space surrounding cerebral blood vessels. Given the variety of hypotheses that have been proposed for AD pathogenesis, an interconnected, multilayer model offers a unique opportunity to combine these ideas into a single unifying model. Results of this model demonstrate the importance of vessel stiffness and heart rate in maintaining adequate clearance of Aβ from the brain.

  16. Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds

    International Nuclear Information System (INIS)

    The Pacific Northwest National Laboratory is developing a generalized fabrication flaw distribution for the population of nuclear reactor pressure vessels and for piping welds in U.S. operating reactors. The purpose of the generalized flaw distribution is to predict component-specific flaw densities. The estimates of fabrication flaws are intended for use in fracture mechanics structural integrity assessments. Structural integrity assessments, such as estimating the frequency of loss-of-coolant accidents, are performed by computer codes that require, as input, accurate estimates of flaw densities. Welds from four different reactor pressure vessels and a collection of archived pipes have been studied to develop empirical estimates of fabrication flaw densities. This report describes the fabrication flaw distribution and characterization in the repair weld metal of vessels and piping. This work indicates that large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the ends of the repair cavities. Parametric analysis using an exponential fit is performed on the data. The relevance of construction records is established for describing fabrication processes and product forms. An analysis of these records shows there was a significant change in repair frequency over the years when these components were fabricated. A description of repair flaw morphology is provided with a discussion of fracture mechanics significance. Fabrication flaws in repairs are characterized using optimized-access, high-sensitivity nondestructive ultrasonic testing. Flaw characterizations are then validated by other nondestructive evaluation techniques and complemented by destructive testing

  17. Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds

    Energy Technology Data Exchange (ETDEWEB)

    GJ Schuster, FA Simonen, SR Doctor

    2008-04-01

    The Pacific Northwest National Laboratory is developing a generalized fabrication flaw distribution for the population of nuclear reactor pressure vessels and for piping welds in U.S. operating reactors. The purpose of the generalized flaw distribution is to predict component-specific flaw densities. The estimates of fabrication flaws are intended for use in fracture mechanics structural integrity assessments. Structural integrity assessments, such as estimating the frequency of loss-of-coolant accidents, are performed by computer codes that require, as input, accurate estimates of flaw densities. Welds from four different reactor pressure vessels and a collection of archived pipes have been studied to develop empirical estimates of fabrication flaw densities. This report describes the fabrication flaw distribution and characterization in the repair weld metal of vessels and piping. This work indicates that large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the ends of the repair cavities. Parametric analysis using an exponential fit is performed on the data. The relevance of construction records is established for describing fabrication processes and product forms. An analysis of these records shows there was a significant change in repair frequency over the years when these components were fabricated. A description of repair flaw morphology is provided with a discussion of fracture mechanics significance. Fabrication flaws in repairs are characterized using optimized-access, high-sensitivity nondestructive ultrasonic testing. Flaw characterizations are then validated by other nondestructive evaluation techniques and complemented by destructive testing.

  18. An Experimental Study to Replace the Thoracic Descending Aorta for Pigs with a Self-Made Sutureless Blood Vessel

    Directory of Open Access Journals (Sweden)

    Fenglin Song

    2014-01-01

    Full Text Available To simplify the procedure of blood vessel replacement operation and shorten the vascular anastomosis time, we developed a special artificial blood vessel which can be connected to native blood vessels without suture. The self-made sutureless blood vessel (SMSBV was made from two titanium connectors and a Gore-Tex graft. To investigate blood compatibility and histocompatibility of the SMSBV, we carried thoracic descending aorta replacement using either SMSBV or Gore-Tex, respectively, in pigs. The aortic clamp time and the operative blood loss in the experimental group (using SMSBV were less than those in the control group (using Gore-Tex. The whole blood hematocrit, platelet count, plasma soluble P-selectin, plasma free hemoglobin, and interleukins 2, 6 at each time point were not different significantly between the two groups. Light microscopy and transmission electron microscopy examination showed there were layers of vascular smooth muscle cells and endothelial cells adhered in the inner wall of artificial blood vessel without any signs of thrombosis. Based on the result, we have drawn the conclusion that the application of SMSBV can significantly shorten the vascular anastomosis time, reduce operative blood loss, and show good blood and tissue compatibility.

  19. Biological impact of vascular endothelial growth factor on vessel density and survival in multiple myeloma and plasmacytoma.

    Science.gov (United States)

    Swelam, Wael M; Al Tamimi, Dalal M

    2010-11-15

    We compared the differences in a number of angiogenesis-related immunohistochemical parameters, including microvascular density (MVD) and tumor cell activity, between multiple myeloma (MM) and solitary plasmacytoma (SP). Tissue sections from tumors of MM and SP were immunohistochemically stained and analyzed using ImageJ image analysis software for the expression of vascular endothelial growth factor (VEGF), VEGF receptors (Flt-1 and Flk-1), inducible nitric oxide (iNOS), and anti-apoptotic (Bcl-2) protein. Tumor tissues were cytologically graded as high-, intermediate-, or low-grade. Two pathologists determined the MVD of each section independently by recording the average number of CD34+ blood vessels in 500 unit fields. The arithmetic means for MVD were statistically analyzed using the Student's t-test and the significance level was calculated at P-value bimodal role that is mainly angiogenic in MM and tumorigenic, promoting tumor cell survival in SP. PMID:20709463

  20. Earlywood vessel features in Quercus faginea: relationship between ring width and wood density at two sites in Portugal

    Directory of Open Access Journals (Sweden)

    Sousa VB

    2015-12-01

    Full Text Available Wood anatomy holds relevant information for tree development and timber quality (e.g., wood density, which is important for the sustainability of the species. Quercus faginea Lam. (Portuguese or Lusitanian oak is an autoch­thonous Mediterranean oak species characterized by a shrinking natural distribution area and use abandonment. We studied the variation of several wood properties and their relationships with the aim of determining and possibly increasing the wood economic value of this species. The anatomical features of earlywood vessels (area, number, frequency and proportion were investigated in twenty Q. faginea trees sampled at two locations within the natural distribution of the species in Portugal. Moreover, we analyzed the variation of vessel features from pith to bark, the radial growth and the wood density to search for patterns and relationships among the analyzed parameters. Mean earlywood vessel area increased with cambial age up to 60-70 years and then leveled off. An inverse pattern was found for the number of vessels per ring beyond that age. Similar radial patterns of all vessel features were found at both sites, and no significant differences in earlywood vessel area were found between sites. The within-tree development of earlywood vessels was age-related, though not influenced by growth. Earlywood vessel features explained the variation of wood density, i.e., wood density of Q. faginea was strongly negatively correlated with both mean vessel area and proportion.

  1. "Sausage-string" appearance of arteries and arterioles can be caused by an instability of the blood vessel wall

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian Brings; Beierholm, Ulrik; Mikkelsen, Rene;

    2002-01-01

    Vascular damage induced by acute hypertension is preceded by a peculiar pattern where blood vessels show alternating regions of constrictions and dilations ("sausages on a string"). The pattern occurs in the smaller blood vessels, and it plays a central role in causing the vascular damage...... in vascular wall tension. Despite much research, the mechanisms underlying the sausage pattern have remained unknown. Here we present an anisotropic model of the vessel wall and show that the sausage pattern can arise because of an instability of the vessel wall. The model reproduces many of the key features...... observed experimentally. Most importantly, it suggests that the "sausaging" phenomenon is neither caused by a mechanical failure of the vessel wall due to a high blood pressure nor is it due to standing pressure waves caused by the beating of the heart. Rather, it is the expression of a general instability...

  2. Aldehyde dehydrogenase-independent bioactivation of nitroglycerin in porcine and bovine blood vessels.

    Science.gov (United States)

    Neubauer, Regina; Wölkart, Gerald; Opelt, Marissa; Schwarzenegger, Christine; Hofinger, Marielies; Neubauer, Andrea; Kollau, Alexander; Schmidt, Kurt; Schrammel, Astrid; Mayer, Bernd

    2015-02-15

    The vascular bioactivation of the antianginal drug nitroglycerin (GTN), yielding 1,2-glycerol dinitrate and nitric oxide or a related activator of soluble guanylate cyclase, is catalyzed by aldehyde dehydrogenase-2 (ALDH2) in rodent and human blood vessels. The essential role of ALDH2 has been confirmed in many studies and is considered as general principle of GTN-induced vasodilation in mammals. However, this view is challenged by an early report showing that diphenyleneiodonium, which we recently characterized as potent ALDH2 inhibitor, has no effect on GTN-induced relaxation of bovine coronary arteries (De La Lande et al., 1996). We investigated this issue and found that inhibition of ALDH2 attenuates GTN-induced coronary vasodilation in isolated perfused rat hearts but has no effect on relaxation to GTN of bovine and porcine coronary arteries. This observation is explained by low levels of ALDH2 protein expression in bovine coronary arteries and several types of porcine blood vessels. ALDH2 mRNA expression and the rates of GTN denitration were similarly low, excluding a significant contribution of ALDH2 to the bioactivation of GTN in these vessels. Attempts to identify the responsible pathway with enzyme inhibitors did not provide conclusive evidence for the involvement of ALDH3A1, cytochrome P450, or GSH-S-transferase. Thus, the present manuscript describes a hitherto unrecognized pathway of GTN bioactivation in bovine and porcine blood vessels. If present in the human vasculature, this pathway might contribute to the therapeutic effects of organic nitrates that are not metabolized by ALDH2.

  3. Automatic segmentation of blood vessels from retinal fundus images through image processing and data mining techniques

    Indian Academy of Sciences (India)

    R Geetharamani; Lakshmi Balasubramanian

    2015-09-01

    Machine Learning techniques have been useful in almost every field of concern. Data Mining, a branch of Machine Learning is one of the most extensively used techniques. The ever-increasing demands in the field of medicine are being addressed by computational approaches in which Big Data analysis, image processing and data mining are on top priority. These techniques have been exploited in the domain of ophthalmology for better retinal fundus image analysis. Blood vessels, one of the most significant retinal anatomical structures are analysed for diagnosis of many diseases like retinopathy, occlusion and many other vision threatening diseases. Vessel segmentation can also be a pre-processing step for segmentation of other retinal structures like optic disc, fovea, microneurysms, etc. In this paper, blood vessel segmentation is attempted through image processing and data mining techniques. The retinal blood vessels were segmented through color space conversion and color channel extraction, image pre-processing, Gabor filtering, image postprocessing, feature construction through application of principal component analysis, k-means clustering and first level classification using Naïve–Bayes classification algorithm and second level classification using C4.5 enhanced with bagging techniques. Association of every pixel against the feature vector necessitates Big Data analysis. The proposed methodology was evaluated on a publicly available database, STARE. The results reported 95.05% accuracy on entire dataset; however the accuracy was 95.20% on normal images and 94.89% on pathological images. A comparison of these results with the existing methodologies is also reported. This methodology can help ophthalmologists in better and faster analysis and hence early treatment to the patients.

  4. Cooperative phenomena in two-pulse, two-color laser photocoagulation of cutaneous blood vessels.

    Science.gov (United States)

    Barton, J K; Frangineas, G; Pummer, H; Black, J F

    2001-06-01

    A novel laser system has been developed to study the effects of multiple laser pulses of differing wavelengths on cutaneous blood vessels in vivo, using the hamster dorsal skin flap preparation and in vitro, using cuvettes of whole or diluted blood. The system permits sequenced irradiation with well-defined intrapulse spacing at 532 nm, using a long-pulse frequency-doubled Nd:YAG laser, and at 1064 nm, using a long-pulse Nd:YAG laser. Using this system, we have identified a parameter space where two pulses of different wavelengths act in a synergistic manner to effect permanent vessel damage at radiant exposures where the two pulses individually have little or no effect. Using a two-color pump-probe technique in vitro, we have identified a phenomenon we call greenlight-induced infrared absorption, where a pulse of green light causes photochemical and photothermal modifications to the chemical constituents of blood and results in enhanced infrared absorption. We identify a new chemical species, met-hemoglobin, not normally present in healthy human blood but formed during laser photocoagulation which we believe is implicated in the enhanced near-infrared absorption. PMID:11421070

  5. Accuracy and Precision of MR Blood Oximetry Based On the Long Paramagnetic Cylinder Approximation of Large Vessels

    OpenAIRE

    Langham, Michael C; Magland, Jeremy F; Epstein, Charles L.; Floyd, Thomas F; Wehrli, Felix W.

    2009-01-01

    An accurate non-invasive method to measure hemoglobin oxygen saturation (%HbO2) of deep-lying vessels without catheterization would have many clinical applications. Quantitative MRI may be the only imaging modality that can address this difficult and important problem. MR susceptometry-based oximetry for measuring blood oxygen saturation in large vessels models the vessel as a long paramagnetic cylinder immersed in an external field. The intravascular magnetic susceptibility relative to surro...

  6. In vivo bioimaging as a novel strategy to detect doxorubicin-induced damage to gonadal blood vessels.

    Directory of Open Access Journals (Sweden)

    Hadas Bar-Joseph

    Full Text Available INTRODUCTION: Chemotherapy may induce deleterious effects in normal tissues, leading to organ damage. Direct vascular injury is the least characterized side effect. Our aim was to establish a real-time, in vivo molecular imaging platform for evaluating the potential vascular toxicity of doxorubicin in mice. METHODS: Mice gonads served as reference organs. Mouse ovarian or testicular blood volume and femoral arterial blood flow were measured in real-time during and after doxorubicin (8 mg/kg intravenously or paclitaxel (1.2 mg/kg administration. Ovarian blood volume was imaged by ultrasound biomicroscopy (Vevo2100 with microbubbles as a contrast agent whereas testicular blood volume and blood flow as well as femoral arterial blood flow was imaged by pulse wave Doppler ultrasound. Visualization of ovarian and femoral microvasculature was obtained by fluorescence optical imaging system, equipped with a confocal fiber microscope (Cell-viZio. RESULTS: Using microbubbles as a contrast agent revealed a 33% (P<0.01 decrease in ovarian blood volume already 3 minutes after doxorubicin injection. Doppler ultrasound depicted the same phenomenon in testicular blood volume and blood flow. The femoral arterial blood flow was impaired in the same fashion. Cell-viZio imaging depicted a pattern of vessels' injury at around the same time after doxorubicin injection: the wall of the blood vessels became irregular and the fluorescence signal displayed in the small vessels was gradually diminished. Paclitaxel had no vascular effect. CONCLUSION: We have established a platform of innovative high-resolution molecular imaging, suitable for in vivo imaging of vessels' characteristics, arterial blood flow and organs blood volume that enable prolonged real-time detection of chemotherapy-induced effects in the same individuals. The acute reduction in gonadal and femoral blood flow and the impairment of the blood vessels wall may represent an acute universal doxorubicin

  7. Surgical anatomy of the retroperitoneal spaces, Part III: Retroperitoneal blood vessels and lymphatics.

    Science.gov (United States)

    Mirilas, Petros; Skandalakis, John E

    2010-02-01

    In this article, we discuss the surgical anatomy of the blood vessels and the lymphatic vessels and lymph nodes found in the retroperitoneum. Retroperitoneal blood vessels include the aorta and all its branches--parietal and visceral--from the diaphragm to the pelvis, and the inferior vena cava and its tributaries. The retroperitoneal lymphatics form a very rich and extensive chain. As a general rule, lymphatics follow the arteries and named lymph nodes are found at the root of the arteries. Retroperitoneal nodes of the abdomen comprise the inferior diaphragmatic nodes and the lumbar nodes. The latter are classified as left lumbar (aortic), intermediate (interaorticovenous), and right lumbar (caval). These nodes surround the aorta and the inferior vena cava. Around the aorta lie the paraortic nodes, preaortic nodes (include celiac, superior mesenteric, inferior mesenteric nodes collecting lymph from the splanchna supplied by the homonymous arteries), and retroaortic nodes. Similarly, around the vena cava lie the paracaval, precaval, and retrocaval nodes. Pelvic nodes include the common iliac, external and internal iliac, obturator, and sacral nodes.

  8. Apparatus and method for examining a blood vessel of interest using radiation detected outside the body

    International Nuclear Information System (INIS)

    Stenotic atherosclerotic lesions of the coronary arteries are detected by injecting a number of particulate signal sources such as positron-emitting particles (e.g. gallium 68) into the blood of a subject to determine the velocity of blood flow through the coronary vessels. The particles are tracked in three dimensions whenever they appear in the region of the heart by means of high-resolution high-speed gamma detectors that surround the chest. These recordings of particle position as a function of time are analyzed, and the velocity of blood as it flows through the coronary artery is measured by timing the transit of the particle. From the accumulated data of multiple particle transits through the coronary circulation, a three-dimensional representation of the lumen of the coronary arterial system is constructed

  9. Selective irradiation of the blood vessels by using boron neutron capture reaction - development and its utilization

    International Nuclear Information System (INIS)

    Full text: The purposes are development of the method to irradiate blood vessels selectively by using B-10(n, alpha) Li-7 reaction and examination of its effect on tumor and normal tissues. We made BSH-enclosed large size liposome (=300 nm) conjugated with PEG ; BSH-PEG-liposome. This type liposome is thought to escapes from macrophage in the liver, and can stay in the blood at high concentration level for long time. They are also considered not to be able to leak from the vessels into the surrounding tissues. If they receive neutron, B-10 emits extreme short-range (<9 micron) alpha-particle and recoil Li-7 nucleus. C3H/He mice and tumor model SCCVII were used to examine the character and effect of this type liposome. Thermal neutron irradiation was performed by KUR heavy water facility and B-10 concentrations in the blood or tissues were measured by prompt gamma-ray spectrometry. The B-10 concentration ratio between blood and tumor 30 minutes after BSH-PEG-liposome administration was 35- 40, and this ratio was stable for several hours. The effect on the tumors that received neutrons was examined by colony formation assay. The tumor cell survival rate of the BSH-PEG-liposome neutron group was very slightly suppressed in comparison with that of neutron alone group, however, the growth of the tumors was remarkably suppressed in BSH-PEG-liposome neutron group. In the mice that received whole body neutron irradiation after BSH-PEF-liposome injection, the mouse group of 50 Gy to the endothelium of the vessel did exhibit no death, and in the groups of 127 and 183 Gy, all individuals died. But diarrhea and bloody anal discharge that suggested radiation intestinal death were not observed at all. Cause of the death seemed to be bone marrow death

  10. An Automated Graphical User Interface based System for the Extraction of Retinal Blood Vessels using Kirsch’s Template

    OpenAIRE

    Joshita Majumdar; Souvik Tewary; Shreyosi Chakraborty; Debasish Kundu; Sudipta Ghosh; Sauvik Das Gupta

    2015-01-01

    The assessment of Blood Vessel networks plays an important role in a variety of medical disorders. The diagnosis of Diabetic Retinopathy (DR) and its repercussions including micro aneurysms, haemorrhages, hard exudates and cotton wool spots is one such field. This study aims to develop an automated system for the extraction of blood vessels from retinal images by employing Kirsch’s Templates in a MATLAB based Graphical User Interface (GUI). Here, a RGB or Grey image of the retina (Fundus Phot...

  11. Understanding How Space Travel Affects Blood Vessels: Arterial Remodeling and Functional Adaptations Induced by Microgravity

    Science.gov (United States)

    Delp, Michael; Vasques, Marilyn; Aquilina, Rudy (Technical Monitor)

    2002-01-01

    Ever rise quickly from the couch to get something from the kitchen and suddenly feel dizzy? With a low heart rate and relaxed muscles, the cardiovascular system does not immediately provide the resistance necessary to keep enough blood going to your head. Gravity wins, at least for a short time, before your heart and blood vessels can respond to the sudden change in position and correct the situation. Actually, the human cardiovascular system is quite well adapted to the constant gravitational force of the Earth. When standing, vessels in the legs constrict to prevent blood from collecting in the lower extremities. In the space environment, the usual head-to-foot blood pressure and tissue fluid gradients that exist during the upright posture on Earth are removed. The subsequent shift in fluids from the lower to the upper portions of the body triggers adaptations within the cardiovascular system to accommodate the new pressure and fluid gradients. In animal models that simulate microgravity, the vessels in the head become more robust while those in the lower limbs become thin and lax. Similar changes may also occur in humans during spaceflight and while these adaptations are appropriate for a microgravity environment, they can cause problems when the astronauts return to Earth or perhaps another planet. Astronauts often develop orthostatic intolerance which means they become dizzy or faint when standing upright. This dizziness can persist for a number of days making routine activities difficult. In an effort to understand the physiological details of these cardiovascular adaptations, Dr. Michael Delp at Texas A&M University, uses the rat as a model for his studies. For the experiment flown on STS-107, he will test the hypothesis that blood vessels in the rats' hindlimbs become thinner, weaker, and constrict less in response to pressure changes and to chemical signals when exposed to microgravity. In addition, he will test the hypothesis that arteries in the brain

  12. The Influence of Dome Size, Parent Vessel Angle, and Coil Packing Density on Coil Embolization Treatment in Cerebral Aneurysms

    Science.gov (United States)

    Frakes, David H.; Indahlastari, Aprinda; Ryan, Justin; Babiker, M. Haithem; Nair, Priya; Parthas, Varsha

    2013-11-01

    Intracranial aneurysms (ICAs) are dilated cerebral blood vessels. Treating ICAs effectively prior rupture is crucial since their association with 45% mortality rate. Embolic coiling is the most effective ICA treatment. Series of embolic coils are deployed into the aneurysm with the intent of reaching a sufficient packing density (PD) to help seal off the ICA from circulation. While coiling is effective, treatment failures have been associated with basilar tip aneurysms (BTAs), perhaps because of their geometry. The aim of this study was to examine the effect of dome size, parent vessel (PV) angle, and PD on intraaneurysmal (IA) velocity, crossneck (CN) flow and low wall shear stress (WSS) area using simulations and experiments in idealized BTA models. IA velocity and CN flow decreased after coiling, while low WSS area increased. With increasing PD, IA velocity and CN flow were further reduced, but low WSS area had a minimal change. Coil PD had the greatest impact on post-treatment flow while dome size had a greater impact than PV angle. Overall, the role of aneurysmal geometries may vary depending on treatment goal and timing e.g., high coil PD may reduce IA velocity more effectively during early aneurysmal growth when the dome size is small. Funded by the American Heart Association.

  13. Beta-adrenoceptor-mediated vasodilation of retinal blood vessels is reduced in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Nakazawa, Taisuke; Sato, Ayumi; Mori, Asami; Saito, Maki; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2008-01-01

    We investigated the effects of epinephrine and dopamine on retinal blood vessels in streptozotocin (STZ, 80 mg/kg, i.p.)-treated rats and age-matched control rats to determine whether diabetes mellitus alters the retinal vascular responses to circulating catecholamines. Experiments were performed 6-8 weeks after treatment with STZ or the vehicle. The fundus images were captured with the digital fundus camera system for small animals we developed and diameters of retinal blood vessels contained in the digital images were measured. Epinephrine increased the diameters of retinal blood vessels, but the vasodilator responses were reduced in diabetic rats. Dopamine produced a biphasic retinal vascular response with an initial vasoconstriction followed by a vasodilation. The vasoconstrictor effects of dopamine on retinal arterioles were enhanced in diabetic rats, whereas the difference between the two groups was abolished by treatment with propranolol. The vasodilator effect of isoproterenol, but not of the activator of adenylyl cyclase colforsin, on retinal blood vessels was reduced in diabetic rats. No difference in vasoconstriction of retinal blood vessels to phenylephrine between non-diabetic and diabetic rats was observed. The vasodilator responses of retinal blood vessels to 1,1-dimethyl-4-phenylpiperazinium, a ganglionic nicotinic receptor agonist, were also attenuated in diabetic rats. These results suggest that diabetes mellitus alters the retinal vascular responses to circulating catecholamines and the impairment of vasodilator responses mediated by beta-adrenoceptors contributes to the alteration.

  14. In Silico Magnetic Nanocontainers Navigation in Blood Vessels: A Feedback Control Approach.

    Science.gov (United States)

    Do, Ton Duc; Noh, Yeongil; Kim, Myeong Ok; Yoon, Jungwon

    2016-06-01

    Magnetic nanoparticles (MNPs) are recently used in a drug delivery system to pass the blood brain barrier. However, because the magnetic force acting on particles is proportional to their volumes, as the size of particles is small, the large magnetic field is required to produce enough magnetic force for overcoming the hydrodynamic drag force as well as other forces in blood vessels. Other difficulties for controlling MNPs are the complicated behavior of hydrodynamic drag force and uncertain factors in their dynamics. Therefore, open-loop control methods cannot guarantee guiding every MNP to the correct location. Considering these challenges, this paper introduces a feedback control approach for magnetic nanoparticles (MNPs) in blood vessels. To the best of our knowledge, this is the first time feedback controller that is designed for MNPs without aggregation. Simulation studies in MATLAB and real-time verifications on a physical model in COMSOL-MATLAB interface are performed to prove the feasibility of the proposed approach. It is shown that the proposed control scheme can accurately and effectively navigate the MNP to the correct path with feasible hardware supports. PMID:27427720

  15. In Silico Magnetic Nanocontainers Navigation in Blood Vessels: A Feedback Control Approach.

    Science.gov (United States)

    Do, Ton Duc; Noh, Yeongil; Kim, Myeong Ok; Yoon, Jungwon

    2016-06-01

    Magnetic nanoparticles (MNPs) are recently used in a drug delivery system to pass the blood brain barrier. However, because the magnetic force acting on particles is proportional to their volumes, as the size of particles is small, the large magnetic field is required to produce enough magnetic force for overcoming the hydrodynamic drag force as well as other forces in blood vessels. Other difficulties for controlling MNPs are the complicated behavior of hydrodynamic drag force and uncertain factors in their dynamics. Therefore, open-loop control methods cannot guarantee guiding every MNP to the correct location. Considering these challenges, this paper introduces a feedback control approach for magnetic nanoparticles (MNPs) in blood vessels. To the best of our knowledge, this is the first time feedback controller that is designed for MNPs without aggregation. Simulation studies in MATLAB and real-time verifications on a physical model in COMSOL-MATLAB interface are performed to prove the feasibility of the proposed approach. It is shown that the proposed control scheme can accurately and effectively navigate the MNP to the correct path with feasible hardware supports.

  16. Effects of Scopolamine on Blood Vessels in Rabbit Ear after Sympathetic and Sensory Denervation

    Institute of Scientific and Technical Information of China (English)

    刘书勤; 臧伟进; 成亮; 李增利; 于晓江; 李宝平

    2004-01-01

    Objectives To investigate the effects and involved mechanisms of scopolamine (Scop) on rabbit ear blood vessels. Methods Rabbit ear blood vessels were desympathetic and desensory innervation with surgical operation. Diameters of dorsal auricular arterial trunks in vivo were measured with a pair of compasses and the ruler in a dissecting microscope, and effluents from isolated ear under constant perfusion pressure were recorded with a digital drop-recorder. Results Intramuscular injection of Scop 0.1 mg/kg made the diameter of denerved dorsal auricular arterial trunks, as well as that of innerved ones, significantly increased. Scop by itself, at the maximal concentration (Cmax) of 3 μM, 30 μM and 300 μM, did not alter the effluent flow from the isolated denervated rabbit ear, but chlorpromazine (CPZ), at Cmax of 1 μM, acetylcholine (ACh), 0.25μM, all significantly increased the effluent flow, and norepinephrine (NE), 0.1μM, significantly decreased the effluent. Scop, 3 μM, did not affect ACh (0.25μM)-induced the increase of effluent flow, but Scop,30μM, alleviated the increase. Scop, 3μM, did not affect NE (0.1 μM)-induced the decrease of effluent flow, but Scop, 10, 30 and 100 μM, significantly alleviated the decrease. Conclusions The study suggests that Scop has no direct vasodilator effect. The vasodilator effect of Scop is not due to the blockade of muscarinic receptor. However, Scop can dilate blood vessels contracted by α1-adrenoceptor activation.

  17. A numerical analysis on the curved bileaflet Mechanical Heart Valve (MHV) : leaflet motion and blood flow in an elastic blood vessel

    International Nuclear Information System (INIS)

    In blood flow passing through the Mechanical Heart Valve (MHV) and elastic blood vessel, hemolysis and platelet activation causing thrombus formation can be seen owing to the shear stress in the blood. Also, fracture and deformation of leaflets can be observed depending on the shape and material properties of the leaflets which is opened and closed in a cycle. Hence, comprehensive study is needed on the hemodynamics which is associated with the motion of leaflet and elastic blood vessel in terms of fluid-structure interaction. In this paper, a numerical analysis has been performed for a three-dimensional pulsatile blood flow associated with the elastic blood vessel and curved bileaflet for multiple cycles in light of fluid-structure interaction. From this analysis fluttering phenomenon and rebound of the leaflet have been observed and recirculation and regurgitation have been found in the flow fields of the blood. Also, the pressure distribution and the radial displacement of the elastic blood vessel have been obtained. The motion of the leaflet and flow fields of the blood have shown similar tendency compared with the previous experiments carried out in other studies. The present study can contribute to the design methodology for the curved bileaflet mechanical heart valve. Furthermore, the proposed fluid-structure interaction method will be effectively used in various fields where the interaction between fluid flow and structure are involved

  18. A Pulsatile Flow Phantom for Image-Guided HIFU Hemostasis of Blood Vessels

    Science.gov (United States)

    Greaby, Robyn; Vaezy, Shahram

    2005-03-01

    A pulsatile flow phantom for studying ultrasound image-guided acoustic hemostasis in a controlled environment has been developed. An ex vivo porcine carotid artery was attached to the phantom and embedded in a visually and ultrasonically transparent gel. Heparinized porcine blood was pumped through the phantom. Power-Doppler and B-mode ultrasound were used to remotely target the HIFU focus to the site of a needle puncture. In nine trials, complete hemostasis was achieved after an average HIFU application of 55 +/- 34 seconds. The vessels remained patent after treatment. With this phantom, it will be possible to do controlled studies of ultrasound image-guided acoustic hemostasis.

  19. THE STEADY/PULSATILE FLOW AND MACROMOLECULAR TRANSPORT IN T-BIFURCATION BLOOD VESSELS

    Institute of Scientific and Technical Information of China (English)

    李丁; 温功碧

    2003-01-01

    A numerical analysis of the steady and pulsatile, macromolecular( such as lowdensity lipopotein ( LDL ), Albumin ) transport in T-bifurcation was proposed. Theinfluence of Reynolds number and mass flow ratio etc. parameters on the velocity field andmass transport were calculated. The computational results predict that the blood flow factorsaffect the macromolecular distribution and the transport across the wall, it shows thathemodynamic play an important role in the process of atherosclerosis . The LDL and Albuminconcentration on the wall varies most greatly in flow bifurcation area where the wall shearstress varies greatly at the branching vessel and the atherosclerosis often appears there.

  20. Effects of a protein glycocalyx in the hemodynamics of small blood vessels

    Science.gov (United States)

    Dimakopoulos, Yiannis; Delidakis, George; Tsamopoulos, John

    2015-11-01

    Glycocalyx is a protein layer of approximate thickness 0.5 μm that lines vessel walls. We study the effects this layer has on the blood flow inside arterioles and venules, where the relative size of the glycocalyx is significant. To properly describe phenomena that naturally occur in blood flow, such as the inhomogeneous distribution of red blood cells and their aggregation, we use an improved viscoelastic constitutive model. The glycocalyx layer is modeled as fixed porous media. Cells cannot penetrate inside it, since its hydraulic permeability is very low, and the flow inside this layer is described by the equations for a viscous fluid with an extra Brinkman term to account for the effects the porous medium has on the flow. The closed set of equations is solved using the Finite Element method, assuming steady-state with dependence only in the r-direction. Our results are favorably compared with the in vivo velocity profiles in venules of mice produced by Damiano et al. (2004) and the formation of cell-free layer near glycocalyx. Flow inside the glycocalyx layer is found to be severely attenuated due to the low hydraulic permeability, which can have interesting implications in the transport of various substances form the blood to the tissues or in the use of shear stresses as signals for the endothelial surface cells. Finally, we simulate the transient blood flow under pulsatile conditions.

  1. 3-D segmentation of retinal blood vessels in spectral-domain OCT volumes of the optic nerve head

    Science.gov (United States)

    Lee, Kyungmoo; Abràmoff, Michael D.; Niemeijer, Meindert; Garvin, Mona K.; Sonka, Milan

    2010-03-01

    Segmentation of retinal blood vessels can provide important information for detecting and tracking retinal vascular diseases including diabetic retinopathy, arterial hypertension, arteriosclerosis and retinopathy of prematurity (ROP). Many studies on 2-D segmentation of retinal blood vessels from a variety of medical images have been performed. However, 3-D segmentation of retinal blood vessels from spectral-domain optical coherence tomography (OCT) volumes, which is capable of providing geometrically accurate vessel models, to the best of our knowledge, has not been previously studied. The purpose of this study is to develop and evaluate a method that can automatically detect 3-D retinal blood vessels from spectral-domain OCT scans centered on the optic nerve head (ONH). The proposed method utilized a fast multiscale 3-D graph search to segment retinal surfaces as well as a triangular mesh-based 3-D graph search to detect retinal blood vessels. An experiment on 30 ONH-centered OCT scans (15 right eye scans and 15 left eye scans) from 15 subjects was performed, and the mean unsigned error in 3-D of the computer segmentations compared with the independent standard obtained from a retinal specialist was 3.4 +/- 2.5 voxels (0.10 +/- 0.07 mm).

  2. ADAMTS1 alters blood vessel morphology and TSP1 levels in LNCaP and LNCaP-19 prostate tumors

    International Nuclear Information System (INIS)

    Decreased expression of the angiogenesis inhibitor ADAMTS1 (ADAM metallopeptidase with thrombospondin type 1 motif, 1) has previously been reported during prostate cancer progression. The aim of this study was to investigate the function of ADAMTS1 in prostate tumors. ADAMTS1 was downregulated by shRNA technology in the human prostate cancer cell line LNCaP (androgen-dependent), originally expressing ADAMTS1, and was upregulated by transfection in its subline LNCaP-19 (androgen-independent), expressing low levels of ADAMTS1. Cells were implanted subcutaneously in nude mice and tumor growth, microvessel density (MVD), blood vessel morphology, pericyte coverage and thrombospondin 1 (TSP1) were studied in the tumor xenografts. Modified expression of ADAMTS1 resulted in altered blood vessel morphology in the tumors. Low expression levels of ADAMTS1 were associated with small diameter blood vessels both in LNCaP and LNCaP-19 tumors, while high levels of ADAMTS1 were associated with larger vessels. In addition, TSP1 levels in the tumor xenografts were inversely related to ADAMTS1 expression. MVD and pericyte coverage were not affected. Moreover, upregulation of ADAMTS1 inhibited tumor growth of LNCaP-19, as evidenced by delayed tumor establishment. In contrast, downregulation of ADAMTS1 in LNCaP resulted in reduced tumor growth rate. The present study demonstrates that ADAMTS1 is an important regulatory factor of angiogenesis and tumor growth in prostate tumors, where modified ADAMTS1 expression resulted in markedly changed blood vessel morphology, possibly related to altered TSP1 levels

  3. Apparatus and method for examining a blood vessel of interest using radiation detected outside the body

    International Nuclear Information System (INIS)

    A gamma camera is described in detail for use in examining the blood circulation in vessels adjacent to the heart. The radiation source (e.g. 68Ga) emits positrons whose annihilation is localised and produces two 0.115 MeV gamma rays in exactly opposite directions. By detecting both gamma rays in coincidence in position sensitive multi-wire proportional chambers, lines may be drawn between detected pairs and the intersection of of all such pairs will define the position of the positron emitting source. The radiation source may be tracked in three dimensions by suitably arranging the detectors around the patient's chest. The position of the radiation source can be recorded as a function of time and hence provide information about the velocity of blood flow through each coronary artery. This information may help determine the extent, severity and location of stenotic lesions of the coronary arteries. (U.K.)

  4. A kinematic study of pulsation in the dorsal blood vessel of the blackworm, Lumbriculus variegatus

    Directory of Open Access Journals (Sweden)

    Kameko Halfmann

    2011-01-01

    Full Text Available The aquatic oligochaete Lumbriculus variegatus has a segmented, dorsal blood vessel (DBV that acts as a peristaltic pump to move blood through the animal's closed circulatory system. We conducted a kinematic study using videography and computational modeling as a first step toward understanding the control of DBV pulsation. Results suggested that pulse rates were highest in the posterior segments, while interpulse intervals and intersegmental delays were longest in the midbody segments. Differences in the interpulse interval distributions across regions suggest that some peristaltic waves initiated in the posterior segments do not propagate all the way to the anterior segments. A simple model consisting of a chain of excitable neuromuscular units replicated these kinetics. This model may be useful in future research aimed at understanding the modulatory effect of biogenic amines on peristalsis of the DBV. Moreover, research into the mechanisms of peristalsis of the DBV may lead to insights into disorders of peristalsis in human and veterinary medicine

  5. Blood compatibility of artificial blood vessels probed by infrared spectroscopic imaging

    Science.gov (United States)

    Steiner, Gerald; Maitz, Manfred; Tunc, Sibel; Salzer, Reiner

    2006-02-01

    The determination of protein structure and function plays an important role in biomedical and biochemical research. Common techniques that give full structural information do not permit in-vivo measurements. Infrared spectroscopy has a sufficient sensitivity to examine the structure of proteins solution under in-situ conditions and even on surfaces. However, measurements at few spots on the surface are not suitable to find out the blood compatibility of the protein layer, because the changes in conformation occur often in small domains. Here we report on the investigations of adsorbed fibrinogen with FTIR imaging. FTIR imaging permits an identification of coagulation spots in the micrometer range and the identification of coagulation spots on the implant material.

  6. An Ultrasound Simulation Model for the Pulsatile Blood Flow Modulated by the Motion of Stenosed Vessel Wall.

    Science.gov (United States)

    Zhang, Qinghui; Zhang, Yufeng; Zhou, Yi; Zhang, Kun; Zhang, Kexin; Gao, Lian

    2016-01-01

    This paper presents an ultrasound simulation model for pulsatile blood flow, modulated by the motion of a stenosed vessel wall. It aims at generating more realistic ultrasonic signals to provide an environment for evaluating ultrasound signal processing and imaging and a framework for investigating the behaviors of blood flow field modulated by wall motion. This model takes into account fluid-structure interaction, blood pulsatility, stenosis of the vessel, and arterial wall movement caused by surrounding tissue's motion. The axial and radial velocity distributions of blood and the displacement of vessel wall are calculated by solving coupled Navier-Stokes and wall equations. With these obtained values, we made several different phantoms by treating blood and the vessel wall as a group of point scatterers. Then, ultrasound echoed signals from oscillating wall and blood in the axisymmetric stenotic-carotid arteries were computed by ultrasound simulation software, Field II. The results show better consistency with corresponding theoretical values and clinical data and reflect the influence of wall movement on the flow field. It can serve as an effective tool not only for investigating the behavior of blood flow field modulated by wall motion but also for quantitative or qualitative evaluation of new ultrasound imaging technology and estimation method of blood velocity. PMID:27478840

  7. Electrospun Polycaprolactone Scaffolds for Small-Diameter Tissue Engineered Blood Vessels

    Science.gov (United States)

    Lee, Carol Hsiu-Yueh

    Cardiovascular disease is the leading cause of death in the United States with many patients requiring coronary artery bypass grafting. The current standard is using autografts such as the saphenous vein or intimal mammary artery, however creating a synthetic graft could eliminate this painful and inconvenient procedure. Large diameter grafts have long been established with materials such as DacronRTM and TeflonRTM, however these materials have not proved successful in small-diameter (blood vessel containing microchannels. The benefits of creating a tri-layer is to mimic native arteries that contain an endothelium to prevent thrombosis in the inner layer, aligned smooth muscle cells in the middle to control vasodilation and constriction, and a mechanically robust outer layer. The following work evaluates the mechanical properties of such a graft (tensile, fatigue, burst pressure, and suture retention strength), the ability to rapidly align cells in laser ablated microchannels in PCL scaffolds, and the biological integration (co-culture of endothelial and smooth muscle cells) with electrospun PCL scaffolds. The conclusions from this work establish that the electrospun tri-layers provide adequate mechanical strength as a tissue engineered blood vessel, that laser ablated microchannels are able to contain the smooth muscle cells, and that cells are able to adhere to PCL fibers. However, future work includes adjusting microchannel dimensions to properly align smooth muscle cells along with perfect co-cultures of endothelial and smooth muscle cells on the electrospun tri-layer.

  8. DSA Image Blood Vessel Skeleton Extraction Based on Anti-concentration Diffusion and Level Set Method

    Science.gov (United States)

    Xu, Jing; Wu, Jian; Feng, Daming; Cui, Zhiming

    Serious types of vascular diseases such as carotid stenosis, aneurysm and vascular malformation may lead to brain stroke, which are the third leading cause of death and the number one cause of disability. In the clinical practice of diagnosis and treatment of cerebral vascular diseases, how to do effective detection and description of the vascular structure of two-dimensional angiography sequence image that is blood vessel skeleton extraction has been a difficult study for a long time. This paper mainly discussed two-dimensional image of blood vessel skeleton extraction based on the level set method, first do the preprocessing to the DSA image, namely uses anti-concentration diffusion model for the effective enhancement and uses improved Otsu local threshold segmentation technology based on regional division for the image binarization, then vascular skeleton extraction based on GMM (Group marching method) with fast sweeping theory was actualized. Experiments show that our approach not only improved the time complexity, but also make a good extraction results.

  9. Mycobacterium tuberculosis exploits the formation of new blood vessels for its dissemination

    Science.gov (United States)

    Polena, Helena; Boudou, Frédéric; Tilleul, Sylvain; Dubois-Colas, Nicolas; Lecointe, Cécile; Rakotosamimanana, Niaina; Pelizzola, Mattia; Andriamandimby, Soa Fy; Raharimanga, Vaomalala; Charles, Patricia; Herrmann, Jean-Louis; Ricciardi-Castagnoli, Paola; Rasolofo, Voahangy; Gicquel, Brigitte; Tailleux, Ludovic

    2016-01-01

    The mechanisms by which the airborne pathogen Mycobacterium tuberculosis spreads within the lung and leaves its primary niche to colonize other organs, thus inducing extrapulmonary forms of tuberculosis (TB) in humans, remains poorly understood. Herein, we used a transcriptomic approach to investigate the host cell gene expression profile in M. tuberculosis–infected human macrophages (ΜΦ). We identified 33 genes, encoding proteins involved in angiogenesis, for which the expression was significantly modified during infection, and we show that the potent angiogenic factor VEGF is secreted by M. tuberculosis-infected ΜΦ, in an RD1-dependent manner. In vivo these factors promote the formation of blood vessels in murine models of the disease. Inhibiting angiogenesis, via VEGF inactivation, abolished mycobacterial spread from the infection site. In accordance with our in vitro and in vivo results, we show that the level of VEGF in TB patients is elevated and that endothelial progenitor cells are mobilized from the bone marrow. These results strongly strengthen the most recent data suggesting that mycobacteria take advantage of the formation of new blood vessels to disseminate. PMID:27616470

  10. Segmentation of retinal blood vessels using normalized Gabor filters and automatic thresholding

    Directory of Open Access Journals (Sweden)

    Mandlenkosi Victor Gwetu

    2014-12-01

    Full Text Available Although computerized retinal image blood vessel segmentation has been extensively researched, there is still room for improvement in the quality of the segmented images. Since retinal image analysis is still widely used in the diagnosis of diabetic retinopathy, efficient and accurate image characterization techniques are required. Previous work has mainly focused on improving segmentation accuracy rates with little regard to the false positives that are produced by illumination variation. This research work presents a hybrid approach towards the segmentation of retinal blood vessels. New approaches towards the reduction of background illumination variation are proposed using normalized Gabor filtering. These are the base-offset encoding and a modified version of an existing zero-integral kernel technique. The valley emphasis automatic thresholding scheme is used to segment the Gabor response images. Experiments are conducted on the DRIVE and STARE retinal image data sets. Accuracy rates of up to 94% are achieved through the zero-integral and base offset methods. This is comparable with results from literature, where the same data sets are segmented using other classification techniques. The median-offset method is found to most effectively reduce background illumination variation.

  11. Protective role of a novel human erythrocyte-derived depressing factor on blood vessels in rats

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The protective role of a human erythrocyte-derived depressing factor (EDDF) on blood vessels was evaluated. The experiments were carried out on 25male Wistar rats aged 6-8 weeks, which were divided into control (n = 8), calcium overload (n = 8) and NG-L-nitro-arginine hypertensive model groups (L-NNA,n = 9), respectively. The isolated vascular ring perfusion assay, two-photon laser scanning fluorescence microscopy (TPM) and transmitted electron microscope were used to examine the effect of EDDF on vascular function and ultrastructure. Results showed that the contractile response of calcium overload rats and L-NNA rats to phenylephrine (PE) was significantly enhanced compared with that of the control (P < 0.05), and EDDF (10-3 g @mL-1) remarkably decreased the vascular contractile response of control's and calcium overload rats (P < 0.05),while EDDF had no effect on that of L-NNA rats. EDDF also alleviated the ultrastructural lesion of aorta VSMC in calcium overload rats by easing the abnormal in the nucleus, mitochondrion and other organell. It is concluded that EDDF could efficiently protect blood vessels against injury by influencing Ca2+ transport and ameliorating the lesion of VSMC, and further supported the hypothesis that the NO-cGMP pathway might contribute to the vasodilation and partially antihypertensive mechanism of EDDF.``

  12. Imaging transient blood vessel fusion events in zebrafish by correlative volume electron microscopy.

    Directory of Open Access Journals (Sweden)

    Hannah E J Armer

    Full Text Available The study of biological processes has become increasingly reliant on obtaining high-resolution spatial and temporal data through imaging techniques. As researchers demand molecular resolution of cellular events in the context of whole organisms, correlation of non-invasive live-organism imaging with electron microscopy in complex three-dimensional samples becomes critical. The developing blood vessels of vertebrates form a highly complex network which cannot be imaged at high resolution using traditional methods. Here we show that the point of fusion between growing blood vessels of transgenic zebrafish, identified in live confocal microscopy, can subsequently be traced through the structure of the organism using Focused Ion Beam/Scanning Electron Microscopy (FIB/SEM and Serial Block Face/Scanning Electron Microscopy (SBF/SEM. The resulting data give unprecedented microanatomical detail of the zebrafish and, for the first time, allow visualization of the ultrastructure of a time-limited biological event within the context of a whole organism.

  13. Differential lectin binding on walls of thoraco-cervical blood vessels and lymphatics in rats.

    Science.gov (United States)

    Kagami, H; Uryu, K; Okamoto, K; Sakai, H; Kaneda, T; Sakanaka, M

    1991-08-01

    Lectin binding in the walls of large to medium-sized blood vessels and lymphatics in the rat thoraco-cervical region was examined histochemically. The tunica intima of the aorta and superficial cervical artery showed positive reactions with wheat germ agglutinin (WGA) and Concanavalin A (ConA) but not with Dolichus biflorus agglutinin (DBA). The tunica media of the aorta exhibited intense WGA binding, especially on the smooth muscle cells, but the tunica media of the superficial cervical artery did not react with the lectin. Neither ConA nor DBA bound to the tunica media of the aorta and superficial cervical artery. The tunica adventitia of both arteries contained sites binding the three lectins, although DBA reactivity declined as the vascular diameter decreased. The tunica intima of the superior vena cava and azygos vein exhibited positive WGA and ConA binding, whereas DBA binding was noted on only part of the tunica intima of the superior vena cava and not on that of the azygos vein. The tunica media and tunica adventitia were reactive for all three lectins. The WGA and ConA binding sites in the tunica adventitia showed loose networks, suggesting lectin binding on connective tissue elements interlacing among smooth muscle bundles. Lectin binding sites in the walls of lymphatics exhibited an arrangement similar to those in the walls of the veins. Moreover valves protruding into the lumen showed intense WGA and ConA binding and scattered DBA binding. Three other lectins (Ulex europaeus agglutinin, peanut agglutinin, Maclura pomifera) were examined, but they showed no reactions with the vessels. Thus, the differential binding of lectins on the walls of blood vessels and lymphatics of various sizes suggests the functional complexity of monosaccharide residues in the vascular walls. PMID:1758681

  14. Low cost labeling with highlighter ink efficiently visualizes developing blood vessels in avian and mouse embryos.

    Science.gov (United States)

    Takase, Yuta; Tadokoro, Ryosuke; Takahashi, Yoshiko

    2013-12-01

    To understand how blood vessels form to establish the intricate network during vertebrate development, it is helpful if one can visualize the vasculature in embryos. We here describe a novel labeling method using highlighter ink, easily obtained in stationery stores with a low cost, to visualize embryo-wide vasculatures in avian and mice. We tested 50 different highlighters for fluorescent microscopy with filter sets equipped in a standard fluorescent microscope. The yellow and violet inks yielded fluorescent signals specifically detected by the filters used for green fluorescent protein (GFP) and red fluorescent protein (RFP) detections, respectively. When the ink solution was infused into chicken/quail and mouse embryos, vasculatures including large vessels and capillaries were labeled both in living and fixed embryos. Ink-infused embryos were further subjected to histological sections, and double stained with antibodies including QH-1 (quail), α smooth muscle actin (αSMA), and PECAM-1 (mouse), revealing that the endothelial cells were specifically labeled by the infused highlighter ink. Highlighter-labeled signals were detected with a resolution comparable to or higher than signals of fluorescein isothiocyanate (FITC)-lectin and Rhodamine-dextran, conventionally used for angiography. Furthermore, macroconfocal microscopic analyses with ink-infused embryos visualized fine vascular structures of both embryo proper and extra-embryonic plexus in a Z-stack image of 2400 μm thick with a markedly high resolution. Together, the low cost highlighter ink serves as an alternative reagent useful for visualization of blood vessels in developing avian and mouse embryos and possibly in other animals.

  15. Fractals and fractal dimension of systems of blood vessels: An analogy between artery trees, river networks, and urban hierarchies

    CERN Document Server

    Chen, Yanguang

    2015-01-01

    An analogy between the fractal nature of networks of arteries and that of systems of rivers has been drawn in the previous works. However, the deep structure of the hierarchy of blood vessels has not yet been revealed. This paper is devoted to researching the fractals, allometric scaling, and hierarchy of blood vessels. By analogy with Horton-Strahler's laws of river composition, three exponential laws have been put forward. These exponential laws can be reconstructed and transformed into three linear scaling laws, which can be named composition laws of blood vessels network. From these linear scaling laws it follows a set of power laws, including the three-parameter Zipf's law on the rank-size distribution of blood vessel length and the allometric scaling law on the length-diameter relationship of blood vessels in different orders. The models are applied to the observed data on human beings and animals early given by other researchers, and an interesting finding is that human bodies more conform to natural r...

  16. Neutrophil-Mediated Delivery of Therapeutic Nanoparticles across Blood Vessel Barrier for Treatment of Inflammation and Infection.

    Science.gov (United States)

    Chu, Dafeng; Gao, Jin; Wang, Zhenjia

    2015-12-22

    Endothelial cells form a monolayer in lumen of blood vessels presenting a great barrier for delivery of therapeutic nanoparticles (NPs) into extravascular tissues where most diseases occur, such as inflammation disorders and infection. Here, we report a strategy for delivering therapeutic NPs across this blood vessel barrier by nanoparticle in situ hitchhiking activated neutrophils. Using intravital microscopy of TNF-α-induced inflammation of mouse cremaster venules and a mouse model of acute lung inflammation, we demonstrated that intravenously (iv) infused NPs made from denatured bovine serum albumin (BSA) were specifically internalized by activated neutrophils, and subsequently, the neutrophils containing NPs migrated across blood vessels into inflammatory tissues. When neutrophils were depleted using anti-Gr-1 in a mouse, the transport of albumin NPs across blood vessel walls was robustly abolished. Furthermore, it was found that albumin nanoparticle internalization did not affect neutrophil mobility and functions. Administration of drug-loaded albumin NPs markedly mitigated the lung inflammation induced by LPS (lipopolysaccharide) or infection by Pseudomonas aeruginosa. These results demonstrate the use of an albumin nanoparticle platform for in situ targeting of activated neutrophils for delivery of therapeutics across the blood vessel barriers into diseased sites. This study demonstrates our ability to hijack neutrophils to deliver nanoparticles to targeted diseased sites.

  17. Patency of heart blood vessels under photosensitization reaction shortly after intravenous injection of talaporfin sodium in canine model

    Science.gov (United States)

    Hamada, Risa; Matsuzaki, Ryota; Ogawa, Emiyu; Arai, Tsunenori

    2016-03-01

    In order to investigate patency of heart blood vessels by photosensitization reaction shortly after intravenous injection of talaporfin sodium, we performed in vitro endothelial cell lethality study and in vivo study of heart blood vessel patency in canine one week after photosensitization reaction. Cell lethality of human umbilical vein endothelial cells under different albumin concentrations corresponding with blood and interstice concentrations were employed and their lethality 2 hours after the reaction was measured by WST assay in vitro. Almost all cells survived by 40 J/cm2 photosensitization reaction with blood albumin concentration. Laser diffuser made of plastic optical fiber with 70 mm in length was used in vivo. Red diode laser of 664nm wavelength was emitted from this diffuser with 17.1-42.9 mW/cm in 10 minutes. We estimated the fluence rate distribution by a ray-trace simulator using pre-measured optical coefficients of myocardium tissue, μa 0.12 mm-1 and μs' 0.36 mm-1. Almost all blood vessels were patent in every irradiation conditions in canine heart. Coronary artery and vein up to 1 mm diameter were patent in typical myocardium sample with 25.7 mW/cm. We estimated fluence rate distribution of this sample and found that blood vessels were patent even fluence rate over 40 J/cm2. This in vivo study could be explained by the result of in vitro study. We suggest that this blood vessel patency after our particular photosensitization reaction might be because of few photosensitizer uptake in the blood endothelial cells and/or reduced oxidation damage by thick albumin concentration in blood.

  18. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization

    OpenAIRE

    Birgit Huber; Sascha Engelhardt; Wolfdietrich Meyer; Hartmut Krüger; Annika Wenz; Veronika Schönhaar; Tovar, Günter E. M.; Kluger, Petra J.; Kirsten Borchers

    2016-01-01

    Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of appr...

  19. Distinct mechanisms of relaxation to bioactive components from chamomile species in porcine isolated blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, R.E., E-mail: Richard.roberts@nottingham.ac.uk; Allen, S.; Chang, A.P.Y.; Henderson, H.; Hobson, G.C.; Karania, B.; Morgan, K.N.; Pek, A.S.Y.; Raghvani, K.; Shee, C.Y.; Shikotra, J.; Street, E.; Abbas, Z.; Ellis, K.; Heer, J.K.; Alexander, S.P.H., E-mail: steve.alexander@nottingham.ac.uk

    2013-11-01

    German chamomile (Matricaria recutita L.), a widely-used herbal medicine, has been reported to have a wide range of biological effects, including smooth muscle relaxation. The aim of this study was to compare the effects of representative compounds from chamomile (apigenin, luteolin, (−)-α-bisabolol, farnesene, umbelliferone; 3–30 μM) on vascular tone using porcine coronary and splenic arteries mounted for isometric tension recording in isolated tissue baths and precontracted with the thromboxane-mimetic U46619. Apigenin, luteolin, and (−)-α-bisabolol produced slow, concentration-dependent relaxations in both the coronary and splenic arteries that were not blocked by inhibition of nitric oxide synthase or potassium channels. Removal of extracellular calcium inhibited the relaxations to all three compounds, and these compounds also inhibited calcium re-addition-evoked contractions, indicating that the relaxation response may be mediated through inhibition of calcium influx. Apigenin and luteolin, but not (−)-α-bisabolol, enhanced the relaxation to the nitric oxide donor sodium nitroprusside, indicating that apigenin and luteolin may act to regulate cyclic GMP levels. Umbelliferone produced a rapid, transient relaxation in the splenic artery, but not the coronary artery, that was inhibited by L-NAME and removal of the endothelium, suggesting an influence on nitric oxide production. Farnesene, at concentrations up to 30 μM, was without effect in either blood vessel. In conclusion, hydroxylated compounds (apigenin, luteolin and (−)-α-bisabolol) found in chamomile all caused a slow relaxation of isolated blood vessels through an effect on calcium influx. Umbelliferone, on the other hand, produced a rapid, transient relaxation dependent upon release of nitric oxide from the endothelium. - Highlights: • Apigenin, luteolin, and (-)-α-bisabolol are present in chamomile. • They produced slow, concentration-dependent relaxations in arteries. • These

  20. The Effect of Silver Nanofibers on the Deformation Properties of Blood Vessels: Towards the Development of New Nanotechnologies to Prevent Rupture of Aneurysms

    Directory of Open Access Journals (Sweden)

    Miguel Gonzalez

    2014-01-01

    Full Text Available An aneurysm is the result of a widening or ballooning of a portion of a blood vessel. The rupture of an aneurysm occurs when the mechanical stress acting on the inner wall exceeds the failure strength of the blood vessel. We propose an innovative approach to prevent the rupture of an aneurysm based on the use of nanotechnology to improve the strength of the blood vessel. We present results on the effect of silver nanofibers on the resistance toward deformation of blood vessels. The silver nanofibers are grown on the surface of the blood vessels. The nanofibers are 120±30 nm in diameter and 2.7±0.8 μm in length. The deformation per applied force of blood vessels was found to decrease from 0.15 m/N in control blood vessels to 0.003 m/N in blood vessels treated with the nanofibers. This represents an increase in the resistance towards deformation of a factor of 50. The increase in the resistance towards deformation is clinically significant since blood pressure increases by factors slightly larger than one in the human body. Treatment of blood vessels with silver nanofibers is a potential translational clinical tool for preventing rupture of aneurysms in a clinical setting.

  1. 3-D trajectory model for MDT using micro-spheres implanted within large blood vessels

    Science.gov (United States)

    Choomphon-anomakhun, Natthaphon; Natenapit, Mayuree

    2016-09-01

    Implant assisted magnetic drug targeting (IA-MDT) using ferromagnetic spherical targets implanted within large blood vessels and subjected to a uniform externally applied magnetic field (H0) has been investigated and reported for the first time. The capture areas (As) of magnetic drug carrier particles (MDCPs) were determined from the analysis of particle trajectories simulated from equations of motion. Then, the effects of various parameters, such as types of ferromagnetic materials in the targets and MDCPs, blood flow rates, mass fraction of the ferromagnetic material in the MDCPs, average radii of MDCPs (Rp) and the strength of H0 on the As were obtained. Furthermore, the effects of saturation magnetization of the ferromagnetic materials in the MDCPs and within the targets on the As were analyzed. After this, the suitable strengths of H0 and Rp for IA-MDT designs were reported. Dimensionless As, ranging from 2 to 7, was obtained with Rp ranging from 500 to 2500 nm, μ0H0 less than 0.8 T and a blood flow rate of 0.1 m s-1. The target-MDCP materials considered are iron-iron, iron-magnetite and SS409-magnetite, respectively.

  2. Maturation of blood vessels by haematopoietic stem cells and progenitor cells: involvement of apelin/APJ and angiopoietin/Tie2 interactions in vessel caliber size regulation.

    Science.gov (United States)

    Takakura, Nobuyuki; Kidoya, Hiroyasu

    2009-06-01

    Apelin is a recently-isolated bioactive peptide from bovine gastric extract. The gene encodes a protein of 77 amino acids, which can generate two active polypeptides, long (42-77) and short (65-77). Both peptides ligate and activate APJ, a G protein-coupled receptor expressed in the cardiovascular and central nervous systems. Although an essential role for the apelin/APJ system in blood vessel formation has been reported in Xenopus, its precise function in mammals is unclear. Blood vessel tube formation is accomplished by two main mechanisms: 1) single cell hollowing, in which a lumen forms within the cytoplasm of a single endothelial cell (EC), and 2) cord hollowing in which a luminal cavity is created de novo between ECs in a thin cylindrical cord. Molecular control of either single cell or cord hollowing has not been precisely determined. Angiopoietin-1 (Ang1) has been reported to induce enlargement of blood vessels. Apelin is produced from ECs upon activation of Tie2, a cognate receptor of Ang1, expressed on ECs. It has been suggested that apelin induces cord hollowing by promoting proliferation and aggregation/assembly of ECs. During angiogenesis, haematopoietic stem cells (HSCs) and progenitor cells (HPCs) are frequently observed in the perivascular region. They produce Ang1 and induce migration of ECs, resulting in a fine vascular network. Moreover, HSCs/HPCs can induce apelin production from ECs. Therefore, this review article posits that HSCs/HPCs regulate caliber size of blood vessels via apelin/APJ and Angiopoietin/Tie2 interactions.

  3. The Influence for Heart and Blood Vessel of Resperdone%利培酮对心血管的影响

    Institute of Scientific and Technical Information of China (English)

    丁智平; 戴兴海; 廖慧珍

    2002-01-01

    Objective To research the influence of the Risperidone for heart and blood vessel and to contral for Clozapine. Method Schizophrenic patients who were in hospital and conform to diagnostic criteria of CCMD- 2- R were been divided Risperidone group and Clozapine group. Two group patients were been examined EKG before and after treatment one、two、three months. Results The influence for heart and blood vessel of Risperidone group were mainly Sinus bradycardia and T wave change but lower for Clozapine group. The influence was associated with the time of taking the drugs Conclusion There was influence on heart and blood vessel of Risperidone but the extend of influencc was lower for Clozapine and must give rise to pay attention.

  4. Accuracy and precision of MR blood oximetry based on the long paramagnetic cylinder approximation of large vessels.

    Science.gov (United States)

    Langham, Michael C; Magland, Jeremy F; Epstein, Charles L; Floyd, Thomas F; Wehrli, Felix W

    2009-08-01

    An accurate noninvasive method to measure the hemoglobin oxygen saturation (%HbO(2)) of deep-lying vessels without catheterization would have many clinical applications. Quantitative MRI may be the only imaging modality that can address this difficult and important problem. MR susceptometry-based oximetry for measuring blood oxygen saturation in large vessels models the vessel as a long paramagnetic cylinder immersed in an external field. The intravascular magnetic susceptibility relative to surrounding muscle tissue is a function of oxygenated hemoglobin (HbO(2)) and can be quantified with a field-mapping pulse sequence. In this work, the method's accuracy and precision was investigated theoretically on the basis of an analytical expression for the arbitrarily oriented cylinder, as well as experimentally in phantoms and in vivo in the femoral artery and vein at 3T field strength. Errors resulting from vessel tilt, noncircularity of vessel cross-section, and induced magnetic field gradients were evaluated and methods for correction were designed and implemented. Hemoglobin saturation was measured at successive vessel segments, differing in geometry, such as eccentricity and vessel tilt, but constant blood oxygen saturation levels, as a means to evaluate measurement consistency. The average standard error and coefficient of variation of measurements in phantoms were cylinder approximation of the incremental field. PMID:19526517

  5. Multi-detector spiral CT study of the relationships between pulmonary ground-glass nodules and blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Feng; Li, Ming; Ge, Xiaojun; Ren, Qingguo; Hua, Yanqing [Huadong Hospital Fudan University, Department of Radiology, Shanghai (China); Zheng, Xiangpeng [Huadong Hospital Fudan University, Department of Radiation Oncology, Shanghai (China); Chen, Yan [Huadong Hospital Fudan University, Department of Pathology, Shanghai (China); Lv, Fangzhen [Huadong Hospital Fudan University, Department of Thoracic Surgery, Shanghai (China)

    2013-12-15

    To investigate the relationships between pulmonary ground-glass nodules (GGN) and blood vessels and their diagnostic values in differentiating GGNs. Multi-detector spiral CT imaging of 108 GGNs was retrospectively reviewed. The spatial relationships between GGNs and supplying blood vessels were categorized into four types: I, vessels passing by GGNs; II, intact vessels passing through GGNs; III, distorted, dilated or tortuous vessels seen within GGNs; IV, more complicated vasculature other than described above. Relationship types were correlated to pathologic and/or clinical findings of GGNs. Of 108 GGNs, 10 were benign, 24 preinvasive nodules and 74 adenocarcinomas that were pathologically proven. Types I, II, III and IV vascular relationships were observed in 9, 58, 21 and 20 GGNs, respectively. Type II relationship was the dominating relationship for each GGN group, but significant differences were shown among them. Correlation analysis showed strong correlation between invasive adenocarcinoma and type III and IV relationships. Subgroup analysis indicated that type III was more commonly seen in IAC with comparison to type IV more likely seen in MIA. Different GGNs have different relationships with vessels. Understanding and recognising characteristic GGN-vessel relationships may help identify which GGNs are more likely to be malignant. (orig.)

  6. High-resolution time series of vessel density in Kenyan mangrove trees reveal a link with climate.

    Science.gov (United States)

    Verheyden, Anouk; De Ridder, Fjo; Schmitz, Nele; Beeckman, Hans; Koedam, Nico

    2005-08-01

    Tropical trees are often excluded from dendrochronological investigations because of a lack of distinct growth ring boundaries, causing a gap in paleoclimate reconstructions from tropical regions. The potential use of time series of vessel features (density, diameter, surface area and hydraulic conductivity) combined with spectral analysis as a proxy for environmental conditions in the mangrove Rhizophora mucronata was investigated. Intra-annual differences in the vessel features revealed a trade-off between hydraulic efficiency (large vessels) during the rainy season and hydraulic safety (small, more numerous vessels) during the dry season. In addition to the earlywood-latewood variations, a semiannual signal was discovered in the vessel density and diameters after Fourier transformation. The similarity in the Fourier spectra of the vessel features and the climate data, in particular mean relative humidity and precipitation, provides strong evidence for a climatic driving force for the intra-annual variability of the vessel features. The high-resolution approach used in this study, in combination with spectral analysis, may have great potential for the study of climate variability in tropical regions. PMID:15998396

  7. Comparison of the number of gingival blood vessels between type 2 diabetes mellitus and chronic periodontitis patients: An immunohistological study

    Science.gov (United States)

    Penmetsa, Gautami Subhadra; Baddam, Satyanarayana; Manyam, Ravikanth; Dwarakanath, Chinni Doraswamy

    2015-01-01

    Background: The relationship between diabetes and periodontitis has been studied for more than 50 years and is generally agreed that the periodontal disease is more prevalent in diabetic patients compared to nondiabetics. Vascular changes like increased thickness of basement membrane in small vessels has been reported in diabetic patients, but the quantity of blood vessels in gingiva of diabetic patients has not been discussed much. The aim of this study was to compare the number of blood vessels in gingiva between chronic periodontitis (CP) patients, CP with diabetes (type 2), and normal healthy gingiva. Materials and Methods: The study included 75 patients, divided into three groups of 25 patients each-Group I with healthy periodontium (HP), Group II with CP, and Group III with CP with diabetes mellitus (CPDM). Gingival biopsies were obtained from the subjects undergoing crown lengthening procedure for Group I, and in patients with CP and in CPDM biopsies were collected from teeth undergoing extraction. Sections were prepared for immune histochemical staining with CD34. Results: Difference was observed in the average number of blood vessels when compared between HP, CP, and CPDM groups. Statistical significant difference was observed when the HP and CP groups and HP and CPDM groups were compared. Conclusion: The results of the study indicated that the number of blood vessels in gingival connective tissue is significantly higher in CP and CPDM patients. PMID:26015666

  8. Comparison of the number of gingival blood vessels between type 2 diabetes mellitus and chronic periodontitis patients: An immunohistological study

    Directory of Open Access Journals (Sweden)

    Gautami Subhadra Penmetsa

    2015-01-01

    Full Text Available Background: The relationship between diabetes and periodontitis has been studied for more than 50 years and is generally agreed that the periodontal disease is more prevalent in diabetic patients compared to nondiabetics. Vascular changes like increased thickness of basement membrane in small vessels has been reported in diabetic patients, but the quantity of blood vessels in gingiva of diabetic patients has not been discussed much. The aim of this study was to compare the number of blood vessels in gingiva between chronic periodontitis (CP patients, CP with diabetes (type 2, and normal healthy gingiva. Materials and Methods: The study included 75 patients, divided into three groups of 25 patients each-Group I with healthy periodontium (HP, Group II with CP, and Group III with CP with diabetes mellitus (CPDM.Gingival biopsies were obtained from the subjects undergoing crown lengthening procedure for Group I, and in patients with CP and in CPDM biopsies were collected from teeth undergoing extraction. Sections were prepared for immune histochemical staining with CD34. Results: Difference was observed in the average number of blood vessels when compared between HP, CP, and CPDM groups. Statistical significant difference was observed when the HP and CP groups and HP and CPDM groups were compared. Conclusion: The results of the study indicated that the number of blood vessels in gingival connective tissue is significantly higher in CP and CPDM patients.

  9. Large blood vessel stretch in lumbar spine through anterior surgical approach: An experimental study in adult goat

    Directory of Open Access Journals (Sweden)

    Liehua Liu

    2014-01-01

    Full Text Available Background: Various anterior lumbar surgical approaches, including the minimally invasive approach, have greatly improved in recent years. Vascular complications resulting from ALIF are frequently reported. Little information is available about the safety of large blood vessel stretch. We evaluated the right side stretch limit (RSSL of the abdominal aorta (AAA and the inferior vena cava (IVC without blood flow occlusion and investigated stretch-induced histological injury and thrombosis in the iliac and femoral arteries and veins and the stretched vessels. Materials and Methods: The RSSL of blood vessels in five adult goats was measured by counting the number of 0.5-cm-thick wood slabs that were inserted between the right lumbar edge and the stretch hook. Twenty seven adult goats were divided into three groups to investigate histological injury and thrombosis under a stretch to 0.5 cm (group I 1.5 cm (group II for 2 h, or no stretch (group III. Blood vessel samples from groups I and II were analyzed on postsurgical days 1, 3, and 7. Thrombogenesis was examined in the iliac and femoral arteries and veins. Results: The RSSL of large blood vessels in front of L4/5 was 1.5 cm from the right lumbar edge. All goats survived surgery without complications. No injury or thrombosis in the large blood vessels in front of the lumbar vertebrae and in the iliac or femoral arteries and veins was observed. Under light microscopy, group I showed slight swelling of endothelial cells in the AAA and no histological injury of the IVC. The AAA of group II showed endothelial cell damage, unclear organelles, and incomplete cell connections by electron microscopy. Conclusions: The AAA and IVC in a goat model can be stretched by ≤0.5 cm, with no thrombosis in the AAA, IVC, iliac or femoral arteries and veins.

  10. Streaming flow from ultrasound contrast agents by acoustic waves in a blood vessel model.

    Science.gov (United States)

    Cho, Eunjin; Chung, Sang Kug; Rhee, Kyehan

    2015-09-01

    To elucidate the effects of streaming flow on ultrasound contrast agent (UCA)-assisted drug delivery, streaming velocity fields from sonicated UCA microbubbles were measured using particle image velocimetry (PIV) in a blood vessel model. At the beginning of ultrasound sonication, the UCA bubbles formed clusters and translated in the direction of the ultrasound field. Bubble cluster formation and translation were faster with 2.25MHz sonication, a frequency close to the resonance frequency of the UCA. Translation of bubble clusters induced streaming jet flow that impinged on the vessel wall, forming symmetric vortices. The maximum streaming velocity was about 60mm/s at 2.25MHz and decreased to 15mm/s at 1.0MHz for the same acoustic pressure amplitude. The effect of the ultrasound frequency on wall shear stress was more noticeable. Maximum wall shear stress decreased from 0.84 to 0.1Pa as the ultrasound frequency decreased from 2.25 to 1.0MHz. The maximum spatial gradient of the wall shear stress also decreased from 1.0 to 0.1Pa/mm. This study showed that streaming flow was induced by bubble cluster formation and translation and was stronger upon sonication by an acoustic wave with a frequency near the UCA resonance frequency. Therefore, the secondary radiant force, which is much stronger at the resonance frequency, should play an important role in UCA-assisted drug delivery.

  11. Distinct cellular mechanisms of blood vessel fusion in the zebrafish embryo.

    Science.gov (United States)

    Herwig, Lukas; Blum, Yannick; Krudewig, Alice; Ellertsdottir, Elin; Lenard, Anna; Belting, Heinz-Georg; Affolter, Markus

    2011-11-22

    Although many of the cellular and molecular mechanisms of angiogenesis have been intensely studied [1], little is known about the processes that underlie vascular anastomosis. We have generated transgenic fish lines expressing an EGFP-tagged version of the junctional protein zona occludens 1 (ZO1) to visualize individual cell behaviors that occur during vessel fusion and lumen formation in vivo. These life observations show that endothelial cells (ECs) use two distinct morphogenetic mechanisms, cell membrane invagination and cord hollowing to generate different types of vascular tubes. During initial steps of anastomosis, cell junctions that have formed at the initial site of cell contacts expand into rings, generating a cellular interface of apical membrane compartments, as defined by the localization of the apical marker podocalyxin-2 (Pdxl2). During the cord hollowing process, these apical membrane compartments are brought together via cell rearrangements and extensive junctional remodeling, resulting in lumen coalescence and formation of a multicellular tube. Vessel fusion by membrane invagination occurs adjacent to a preexisting lumen in a proximal to distal direction and is blood-flow dependent. Here, the invaginating inner cell membrane undergoes concomitant apicobasal polarization and the vascular lumen is formed by the extension of a transcellular lumen through the EC, which forms a unicellular or seamless tube. PMID:22079115

  12. Ultrastructural changes in blood vessels in epidermal growth factor treated experimental cutaneous wound model.

    Science.gov (United States)

    Kılıçaslan, Seda M Sarı; Cevher, Sule Coşkun; Peker, Emine G Güleç

    2013-11-01

    This study investigates the impact of epidermal growth factor (EGF) on blood vessels, specifically on the development of intussusceptive angiogenesis in cutaneous wound healing. Excisional wounds were formed on both sides of the medulla spinalis in dorsal location of the rats. The control and EGF-treated groups were divided into two groups with respect to sacrifice day: 5 d and 7 d. EGF was topically applied to the EGF-treated group once a day. The wound tissue was removed from rats, embedded in araldite and paraffin, and then examined under transmission electron and light microscopes. The ultrastructural signs of intussusceptive angiogenesis, such as intraluminal protrusion of endothelial cells and formation of the contact zone of opposite endothelial cells, were observed in the wound. Our statistical analyses, based on light microscopy observations, also confirm that EGF treatment induces intussusceptive angiogenesis. Moreover, we found that induction of EGF impact on intussusceptive angiogenesis is higher on the 7th day of treatment than on the 5th day. This implies that the duration of EGF treatment is important. This research clarifies the effects of EGF on the vessels and proves that EGF induces intussusceptive angiogenesis, being a newer model with respect to sprouting type.

  13. Ultrastructural analysis of small blood vessels in skin biopsies in CADASIL

    Directory of Open Access Journals (Sweden)

    Lačković Vesna

    2008-01-01

    Full Text Available Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL is an inherited small- and medium-artery disease of the brain caused by mutation of the Notch3 gene. Very often, this disease is misdiagnosed. We examined skin biopsies in two members of the first discovered Serbian family affected by CADASIL. Electron microscopy showed that skin blood vessels of both patients contain numerous deposits of granular osmiophilic material (GOM around vascular smooth muscle cells (VSMCs. We observed degeneration of VSMCs, reorganization of their cytoskeleton and dense bodies, disruption of myoendothelial contacts, and apoptosis. Our results suggest that the presence of GOM in small skin arteries represents a specific marker in diagnosis of CADASIL.

  14. Weakly swirling flow in a model of blood vessel with stenosis: Numerical and experimental study

    Directory of Open Access Journals (Sweden)

    Yakov A. Gataulin

    2015-12-01

    Full Text Available Investigation of weakly swirling flow in a model of a blood vessel with asymmetrical stenosis has been performed using both experimental flow measurement techniques (ultrasound Doppler and computational fluid dynamics methods. A special attention is paid to getting data for the length of the reverse-flow zone occurring past the stenosis. It has been established that the laminar steady-state flow model is acceptable for numerical analysis of flow past the given-geometry stenosis at Reynolds number values less than 300. At higher values of this parameter, application of the semi-empirical k-ω SST turbulence model is preferable. It has been shown that flow swirl can lead to an increase of the reverse-flow zone.

  15. Lattice Boltzmann simulation of behaviour of particles moving in blood vessels under the rolling massage

    Institute of Scientific and Technical Information of China (English)

    Yi Hou-Hui; Yang Xiao-Feng; Wang Cai-Feng; Li Hua-Bing

    2009-01-01

    The rolling massage is one of the most important manipulations in Chinese massage, which is expected to eliminate many diseases. Here, the effect of the rolling massage on a pair of particles moving in blood vessels under rolling massage manipulation is studied by the lattice Boltzmann simulation. The simulated results show that the motion of each particle is considerably modified by the rolling massage, and it depends on the relative rolling velocity, the rolling depth, and the distance between particle position and rolling position. Both particles' translational average velocities increase almost linearly as the rolling velocity increases, and obey the same law. The increment of the average relative angular velocity for the leading particle is smaller than that of the trailing one. The result is helpful for understanding the mechanism of the massage and to further develop the rolling techniques.

  16. Wrong theories on the origin of blood vessels: Polybus and De Natura Hominis.

    Science.gov (United States)

    Shoja, Mohammadali M; Tubbs, R Shane; Loukas, Marios; Ardalan, Mohammad R

    2008-06-01

    Polybus of Cos (approximately 400 B.C.) was the son-in-law and the successor of Hippocrates. He is credited with founding the school of Dogmatism, and writing "The Nature of Man" which was important in advancing the theory of the four body humors (humoralism). Some earlier scholars negated Polybus' role as an independent medical figure. However, Corpus Aristotelicum quoted him as having a unique theory regarding the body vasculature which stated that this system was composed of four pairs of blood vessels originating from the head and that these supplied the whole body. In an interpretation of this theory, we opined that numerological mysticism might have been the common motive for both Hippocrates' humoralism and Polybus' theory of the vasculature. A discussion on this issue is presented. PMID:18164081

  17. Cathodic-controlled and near-infrared organic upconverter for local blood vessels mapping

    Science.gov (United States)

    Yuan, Chih-Hsien; Lee, Chih-Chien; Liu, Chun-Fu; Lin, Yun-Hsuan; Su, Wei-Cheng; Lin, Shao-Yu; Chen, Kuan-Ting; Li, Yan-De; Chang, Wen-Chang; Li, Ya-Ze; Su, Tsung-Hao; Liu, Yu-Hsuan; Liu, Shun-Wei

    2016-08-01

    Organic materials are used in novel optoelectronic devices because of the ease and high compatibility of their fabrication processes. Here, we demonstrate a low-driving-voltage cathodic-controlled organic upconverter with a mapping application that converts near-infrared images to produce images of visible blood vessels. The proposed upconverter has a multilayer structure consisting of a photosensitive charge-generation layer (CGL) and a phosphorescent organic light-emitting diode (OLED) for producing clear images with a high resolution of 600 dots per inch. In this study, temperature-dependent electrical characterization was performed to analyze the interfacial modification of the cathodic-controlled upconverter. The result shows that the upconverter demonstrated a high conversion efficiency of 3.46% because of reduction in the injection barrier height at the interface between the CGL and the OLED.

  18. Nanostructural haemocompatible coatings for the internal side of artificial blood vessels

    Science.gov (United States)

    Trembecka-Wojciga, K.; Major, R.; Lackner, J. M.; Butruk-Raszeja, B.; Sanak, M.; Major, B.

    2016-03-01

    The main goal of the work was to elaborate low thrombogenicity of surface inside tube-like elements for cardiovascular system support by combination of low-temperature glow discharge and hydrogel coatings to inhibit blood-clotting cascade activation. A large share of amorphous phase silicon was observed in the microstructure analysis. The crystalline elements were uniformly distributed in the amorphous structure. Combination of low thickness, the proper microstructure and density of the coatings provided a highly flexible nature of the whole system. The blood-material interaction was analyzed in vitro in dynamic conditions by using a designed and fabricated novel blood flow simulator. Coatings deposited by the glow discharge expressed good hemocopatibile properties. The use of hydrogel coatings did not reduce coagulation parameter. Hydrogel coatings did not improve the hemocompatibility of the surface modified with carbon based coatings. Modification of surface with hydrogel resulted in further increased risk of hemolysis.

  19. Factor V Leiden Is Associated with Higher Risk of Deep Venous Thrombosis of Large Blood Vessels

    Science.gov (United States)

    Arsov, Todor; Miladinova, Daniela; Spiroski, Mirko

    2006-01-01

    Aim To determine the prevalence of factor V Leiden mutation in patients with different presentation of venous thromboembolic disease and healthy individuals in the Republic of Macedonia. Methods The retrospective case-control study involved 190 patients with venous thromboembolic disease and 200 healthy individuals, who were screened for the presence of factor V Leiden mutation, using a polymerase chain reaction-restriction fragment length polymorphism method. The prevalence of factor V Leiden was analyzed according to the localization of thrombosis, presence of risk factors, and family history of thrombosis. The odds of deep venous thrombosis were calculated with respect to the presence of factor V Leiden mutation. Results The prevalence of factor V Leiden mutation among patients with venous thromboembolic disease was 21.1%, compared with 5.5% in the healthy individuals. Factor V Leiden positive patients had the first episode of deep venous thrombosis at a younger age, and the prevalence of the mutation was the highest among patients with a positive family history of thrombosis (33.9%, P = 0.003) and in patients with deep venous thrombosis affecting a large blood vessel (37.7%, P = 0.001). The prevalence of factor V Leiden mutation was lower in patients with calf deep venous thrombosis and primary thromboembolism (13.3% and 13.1%, respectively; P>0.05). The odds ratio for iliofemoral or femoral deep venous thrombosis in factor V Leiden carriers was 10.4 (95% confidence interval, 4.7-23.1). Conclusion The prevalence of factor V Leiden mutation was high in patients with venous thromboembolic disease and healthy individuals in the Republic of Macedonia. Factor V Leiden carriers have the highest odds of developing deep venous thrombosis affecting a large venous blood vessel. PMID:16758522

  20. First two cases of living related liver transplantation with complicated anatomy of blood vessels in Beijing

    Institute of Scientific and Technical Information of China (English)

    Wen-Han Wu; Yuan-Lian Wan; Long Lee; Yin-Mo Yang; Yan-Ting Huang; Chao-Long Chen; Sheung-Tat Fan

    2004-01-01

    AIM: Living related liver transplantation (LRLT) has been developed in response to the paediatric organ donor shortage.Though it has been succeeded in many centers worldwide,the safety of the donor is still a major concern, especially in donors with anatomy variation. We succeeded in performing the first two cases of living related liver transplantation with complicated anatomy of blood vessels as a way to overcome cadaveric organ shortage in Beijing.METHODS: Two patients, with congenital liver fibrosis and congenital biliary atresia were performed with living donor liver transplantation in our hospital and then followed up from November 12 to December 13, 2001. The two living donors, mother and father, were healthy aged 34 and 35years. One right lobe (segment Ⅴ, Ⅵ, Ⅶ, Ⅷ) and one left lateral lobe (segment Ⅱ and Ⅲ) were used. The grafts weighed 394 g and 300 g. The ratio of graft weight to the standard liver volume (SLV) of donors was 68% and 27%.The graft weight to recipient body weight ratio was 3.2%and 4.4%. The graft weight to recipient estimated standard liver mass (ESLM) ratio was 63% and 85%. The two donors had complicated blood vessel variation.RESULTS: Two patients undergone living donor liver transplantation had good results. Abnormal liver function with high bilirubin level appeared in a few days after operation, but liver function returned to normal one month after operation with bilirubin level almost decreased to near normal. No bleeding, thrombosis, infection and bile leakage occurred. One had an acute rejection and recovered.The two donors recovered in two weeks. One had slight fever because of a little collection in abdomen and recovered after paracentesis and drainage.CONCLUSION: Living donor liver transplantation has been proved to be a good way that offers a unique opportunity of getting a timely liver graft as a response to shortage of pediatric donors, though it could be a technically difficult operation if there is anatomical

  1. Distinct mechanisms of relaxation to bioactive components from chamomile species in porcine isolated blood vessels.

    Science.gov (United States)

    Roberts, R E; Allen, S; Chang, A P Y; Henderson, H; Hobson, G C; Karania, B; Morgan, K N; Pek, A S Y; Raghvani, K; Shee, C Y; Shikotra, J; Street, E; Abbas, Z; Ellis, K; Heer, J K; Alexander, S P H

    2013-11-01

    German chamomile (Matricaria recutita L.), a widely-used herbal medicine, has been reported to have a wide range of biological effects, including smooth muscle relaxation. The aim of this study was to compare the effects of representative compounds from chamomile (apigenin, luteolin, (-)-α-bisabolol, farnesene, umbelliferone; 3-30 μM) on vascular tone using porcine coronary and splenic arteries mounted for isometric tension recording in isolated tissue baths and precontracted with the thromboxane-mimetic U46619. Apigenin, luteolin, and (-)-α-bisabolol produced slow, concentration-dependent relaxations in both the coronary and splenic arteries that were not blocked by inhibition of nitric oxide synthase or potassium channels. Removal of extracellular calcium inhibited the relaxations to all three compounds, and these compounds also inhibited calcium re-addition-evoked contractions, indicating that the relaxation response may be mediated through inhibition of calcium influx. Apigenin and luteolin, but not (-)-α-bisabolol, enhanced the relaxation to the nitric oxide donor sodium nitroprusside, indicating that apigenin and luteolin may act to regulate cyclic GMP levels. Umbelliferone produced a rapid, transient relaxation in the splenic artery, but not the coronary artery, that was inhibited by L-NAME and removal of the endothelium, suggesting an influence on nitric oxide production. Farnesene, at concentrations up to 30 μM, was without effect in either blood vessel. In conclusion, hydroxylated compounds (apigenin, luteolin and (-)-α-bisabolol) found in chamomile all caused a slow relaxation of isolated blood vessels through an effect on calcium influx. Umbelliferone, on the other hand, produced a rapid, transient relaxation dependent upon release of nitric oxide from the endothelium. PMID:23845591

  2. Tumor Microenvironment and Angiogenic Blood Vessels Dual-Targeting for Enhanced Anti-Glioma Therapy.

    Science.gov (United States)

    Hu, Quanyin; Kang, Ting; Feng, Jingxian; Zhu, Qianqian; Jiang, Tianze; Yao, Jianhui; Jiang, Xinguo; Chen, Jun

    2016-09-14

    Advances in active targeting drug delivery system (DDS) have revolutionized glioma diagnosis and therapy. However, the lack of the sufficient targets on glioma cells and limited penetration capability of DDS have significantly compromised the treatment efficacy. In this study, by taking advantages of the abundant extracellular matrix-derived heparan sulfate proteoglycan (HSPG) and enhanced tumor penetration ability mediated by neuropilin-1 (NRP-1) protein, we reported the ATWLPPR and CGKRK peptide dual-decorated nanoparticulate DDS (designated AC-NP) to achieve angiogenic blood vessels and tumor microenvironment dual-targeting effect. The resulted AC-NP displayed the particle size of 123 ± 19.47 nm. Enhanced cellular association of AC-NP was achieved on HUVEC cells and U87MG cells. AC-NP was internalized via caveolin- and lipid raft-mediated mechanism with the involvement of energy and lysosome in HUVEC cells and via caveolin- and lipid raft-mediated pathway with the participation of energy, microtubulin, and lysosome in U87MG cells. After loading with anticancer drug, paclitaxel (PTX), the enhanced apoptosis induction and antiproliferative activity were achieved by AC-NP. Furthermore, in vitro U87MG tumor spheroids assays showed a deeper penetration and an enhanced inhibitory effect against the U87MG tumor spheroids achieved by AC-NP. In vivo animal experiment showed that decoration of AC peptide on the nanoparticulate DDS resulted in extensive accumulation at glioma site and improved anti-glioma efficacy. Collectively, the results suggested that AC-NP holds great promise to serve as an effective tumor blood vessel and tumor microenvironment dual-targeting DDS with enhanced penetration capability, holding great potential in improving anti-glioma efficacy. PMID:27580101

  3. Use of the Structure of Blood Vessel for Detection of Brain Aneurysm and Route Search to Brain Aneurysm

    Directory of Open Access Journals (Sweden)

    Toshihide Miyagi

    2013-08-01

    Full Text Available In this research, we constructed functions that are necessary for the operation simulation system which assists medical students to inhibit brain aneurysm from exploding. The system reported in this paper is "detection of blood vessels", "detection of brain aneurysm" and "route planning to brain aneurysm". Not only the detection method but also the method to reduce the miss detection is realized for the detection of blood vessel. Finally, the future work will be shown including construction of head model consisting of artery, vein, brain and cranium.

  4. Aging in blood vessels. Medicinal agents FOR systemic arterial hypertension in the elderly.

    Science.gov (United States)

    Rubio-Ruiz, María Esther; Pérez-Torres, Israel; Soto, María Elena; Pastelín, Gustavo; Guarner-Lans, Verónica

    2014-11-01

    Aging impairs blood vessel function and leads to cardiovascular disease. The mechanisms underlying the age-related endothelial, smooth muscle and extracellular matrix vascular dysfunction are discussed. Vascular dysfunction is caused by: (1) Oxidative stress enhancement. (2) Reduction of nitric oxide (NO) bioavailability, by diminished NO synthesis and/or augmented NO scavenging. (3) Production of vasoconstrictor/vasodilator factor imbalances. (4) Low-grade pro-inflammatory environment. (5) Impaired angiogenesis. (6) Endothelial cell senescence. The aging process in vascular smooth muscle is characterized by: (1) Altered replicating potential. (2) Change in cellular phenotype. (3) Changes in responsiveness to contracting and relaxing mediators. (4) Changes in intracellular signaling functions. Systemic arterial hypertension is an age-dependent disorder, and almost half of the elderly human population is hypertensive. The influence of hypertension on the aging cardiovascular system has been studied in models of hypertensive rats. Treatment for hypertension is recommended in the elderly. Lifestyle modifications, natural compounds and hormone therapies are useful for initial stages and as supporting treatment with medication but evidence from clinical trials in this population is needed. Since all antihypertensive agents can lower blood pressure in the elderly, therapy should be based on its potential side effects and drug interactions.

  5. Ultrasound sonication with microbubbles disrupts blood vessels and enhances tumor treatments of anticancer nanodrug

    Directory of Open Access Journals (Sweden)

    Lin CY

    2012-04-01

    Full Text Available Chung-Yin Lin1*, Hsiao-Ching Tseng1*, Heng-Ruei Shiu1, Ming-Fang Wu2, Cheng-Ying Chou3, Win-Li Lin1,41Institute of Biomedical Engineering, 2Laboratory Animal Center, 3Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, Taipei, Taiwan; 4Division of Medical Engineering Research, National Health Research Institutes, Miaoli, Taiwan*These authors contributed equally to this workAbstract: Ultrasound (US sonication with microbubbles (MBs has the potential to disrupt blood vessels and enhance the delivery of drugs into the sonicated tissues. In this study, mouse ear tumors were employed to investigate the therapeutic effects of US, MBs, and pegylated liposomal doxorubicin (PLD on tumors. Tumors started to receive treatments when they grew up to about 15 mm3 (early stage with injection of PLD 10 mg/kg, or up to 50 mm3 (medium stage with PLD 6 (or 4 mg/kg. Experiments included the control, PLD alone, PLD + MBs + US, US alone, and MBs + US groups. The procedure for the PLD + MBs + US group was that PLD was injected first, MB (SonoVue injection followed, and then US was immediately sonicated on the tumor. The results showed that: (1 US sonication with MBs was always able to produce a further hindrance to tumor growth for both early and medium-stage tumors; (2 for the medium-stage tumors, 6 mg/kg PLD alone was able to inhibit their growth, while it did not work for 4 mg/kg PLD alone; (3 with the application of MBs + US, 4 mg/kg PLD was able to inhibit the growth of medium-stage tumors; (4 for early stage tumors after the first treatment with a high dose of PLD alone (10 mg/kg, the tumor size still increased for several days and then decreased (a biphasic pattern; (5 MBs + US alone was able to hinder the growth of early stage tumors, but unable to hinder that of medium stage tumors. The results of histological examinations and blood perfusion measurements indicated that the application of MBs + US disrupts the tumor blood

  6. About a mechanism of the influence of shear stress for viscosity of the blood in vessels of small diameter

    OpenAIRE

    Катюхин, Лев Николаевич

    2014-01-01

    It is proposed a physiological and experimentally confirmed explanation of Fåhraeus-Lindqvist-effect in capillaries using the profile analyses of osmotic deformability of red blood cells. It was shown the dose-dependent change of the erythrocytes deformability in the stage of isotropic spheres after forming artificial water pores (nystatin) and occlusion (PbCl2) of available pores. The Sigma-effect reducing of hematocrit and viscosity in a shear flow of blood through the vessels of a small di...

  7. Single image correlation for blood flow mapping in complex vessel networks

    Science.gov (United States)

    Chirico, Giuseppe; Sironi, Laura; Bouzin, Margaux; D'Alfonso, Laura; Collini, Maddalena; Ceffa, Nicolo'G.; Marquezin, Cassia

    2015-05-01

    Microcirculation plays a key role in the maintenance and hemodynamics of tissues and organs also due to its extensive interaction with the immune system. A critical limitation of state-of-the-art clinical techniques to characterize the blood flow is their lack of the spatial resolution required to scale down to individual capillaries. On the other hand the study of the blood flow through auto- or cross-correlation methods fail to correlate the flow speed values with the morphological details required to describe an intricate network of capillaries. Here we propose to use a newly developed technique (FLICS, FLow Image Correlation Spectroscopy) that, by employing a single raster-scanned xy-image acquired in vivo by confocal or multi-photon excitation fluorescence microscopy, allows the quantitative measurement of the blood flow velocity in the whole vessel pattern within the field of view, while simultaneously maintaining the morphological information on the immobile structures of the explored circulatory system. Fluorescent flowing objects produce diagonal lines in the raster-scanned image superimposed to static morphological details. The flow velocity is obtained by computing the Cross Correlation Function (CCF) of the intensity fluctuations detected in pairs of columns of the image. The whole analytical dependence of the CCFs on the flow speed amplitude and the flow direction has been reported recently. We report here the derivation of approximated analytical relations that allows to use the CCF peak lag time and the corresponding CCF value, to directly estimate the flow speed amplitude and the flow direction. The validation has been performed on Zebrafish embryos for which the flow direction was changed systematically by rotating the embryos on the microscope stage. The results indicate that also from the CCF peak lag time it is possible to recover the flow speed amplitude within 13% of uncertainty (overestimation) in a wide range of angles between the flow and

  8. Three-dimensional multi-scale model of deformable platelets adhesion to vessel wall in blood flow.

    Science.gov (United States)

    Wu, Ziheng; Xu, Zhiliang; Kim, Oleg; Alber, Mark

    2014-08-01

    When a blood vessel ruptures or gets inflamed, the human body responds by rapidly forming a clot to restrict the loss of blood. Platelets aggregation at the injury site of the blood vessel occurring via platelet-platelet adhesion, tethering and rolling on the injured endothelium is a critical initial step in blood clot formation. A novel three-dimensional multi-scale model is introduced and used in this paper to simulate receptor-mediated adhesion of deformable platelets at the site of vascular injury under different shear rates of blood flow. The novelty of the model is based on a new approach of coupling submodels at three biological scales crucial for the early clot formation: novel hybrid cell membrane submodel to represent physiological elastic properties of a platelet, stochastic receptor-ligand binding submodel to describe cell adhesion kinetics and lattice Boltzmann submodel for simulating blood flow. The model implementation on the GPU cluster significantly improved simulation performance. Predictive model simulations revealed that platelet deformation, interactions between platelets in the vicinity of the vessel wall as well as the number of functional GPIbα platelet receptors played significant roles in platelet adhesion to the injury site. Variation of the number of functional GPIbα platelet receptors as well as changes of platelet stiffness can represent effects of specific drugs reducing or enhancing platelet activity. Therefore, predictive simulations can improve the search for new drug targets and help to make treatment of thrombosis patient-specific. PMID:24982253

  9. [Coronary artery blood flow velocity non-invasively measured using a vessel-tracking pulsed Doppler system].

    Science.gov (United States)

    Tateishi, O; Aizawa, O; Okamura, T; Yoshida, T; Furuhata, H; Seo, Y; Iinuma, K; Shiki, E

    1988-09-01

    A newly-developed noninvasive method was used to measure left coronary blood flow during phantom experiments. Two techniques were used in which: (1) the sample position can always be set in a fluctuating vessel using a wall echo-tracking method with a phase-locked-loop, and (2) the Doppler reference signal was generated separately synchronous with the wall echo signal. These techniques were combined, using a commercially available pulsed Doppler apparatus (SSH-40B: Toshiba). Basic experiments were performed using a blood vessel phantom to verify the validity of these systems. Blood flow velocity in the fluctuating tube could be measured clearly using a vessel-tracking method. The blood flow velocity of the left anterior descending artery was measured in three normal subjects and in seven patients from the third intercostal space along the left sternal border. The velocity pattern was characterized by a crescendo-decrescendo shape in diastole. The peak velocity which appeared in diastole ranged from 19 to 69 cm/sec, with no difference by disease entity. However, in all cases, the blood flow velocity signals were marred by extraneous signals, making it impossible to measure blood flow velocity during systole. Further improvement of the system is mandatory in order to use this flowmeter clinically.

  10. Blood vessels in subcaruncular and intercaruncular bovine endometriun possess oxytocin receptors (ORT) and express otr mRNA during pregnancy

    DEFF Research Database (Denmark)

    Fuchs, Anna-Ritta; Balvers, Marga; Ivell, Richard;

    2002-01-01

    is taking place; marked changes were observed with advancing pregnancy. The epithelial cells of the trophoblast were strongly stained for ir OTR and OTR mRNA, as reported last year, but the fetal connective tissue and blood vessels within the trophoblast did not show any stain for ir OTR or OTR m...... placentation because episodic secretion of OT occurs throughout bovine pregnancy...

  11. MRA Images Identification of the Artery Blood Vessel of the Knee with SOM LVQ Neural Networks as Auxiliary.

    Science.gov (United States)

    Huang, Hung-Chun; Chien, Chia-Hung; Shih, Ting-Fang; Chong, Fok-Ching

    2005-01-01

    The ways of angiography are divided into two kinds at present: the invasive type and the non invasive type. Because the magnetic resonance angiography (MRA) has advantages of the non invasive type, thus people can accept MRA more easily. Presently, to diagnoses for the initial stage triage of the blood vessel on clinic by MRA mostly. We to be allowed to see clearly that the shape of lower limb artery which like the dendrite and the blood vessel is thick from the trunk to the thin branch, also we can see the narrow embolism and the blocked place through MRA. This study is aiming at the image of artery of blood vessel by MRA assay, and is attempting to use two-dimensional structure of SOM and LVQ to make out topologies for the shape of artery of blood vessel. We expect that MRA could be useful tools for earlier on the quick triage and auxiliary diagnosis of doctors. By actual examples truly prove that patients after peripheral arterial occlusive disease (PAOD) treatment can diagnose effectively, shorten the time of patients waiting for reports and improve the whole efficiency of the medical treatment system.

  12. NOK/STYK1 promotes the genesis and remodeling of blood and lymphatic vessels during tumor progression.

    Science.gov (United States)

    Liu, Yue; Li, Tianqi; Hu, Dan; Zhang, Shuping

    2016-09-01

    Previous studies have indicated that the overexpression of NOK, also named STYK1, led to tumorigenesis and metastasis. Here, we provide evidence that increased expression of NOK/STYK1 caused marked alterations in the overall and inner structures of tumors and substantially facilitates the genesis and remodeling of the blood and lymphatic vessels during tumor progression. In particular, NOK-expressed HeLa stable cells (HeLa-K) significantly enhanced tumor growth and metastasis in xenografted nude mice. Hematoxylin and eosin (HE) staining demonstrated that the tumor tissues generated by HeLa-K cells were much more ichorous and had more interspaces than those generated by control HeLa cells (HeLa-C). The fluorescent areas stained with cluster of differentiation 31 (CD31), a marker protein for blood vessels, appeared to be in different patterns. The total blood vessels, especially the ring patterns, within the tumors of the HeLa-K group were highly enriched compared with those in the HeLa-C group. NOK-HA was demonstrated to be well colocalized with CD31 in the wall of the tubular structures within tumor tissues. Interestingly, antibody staining of the lymphatic vessel endothelial hyaluronan receptor (LYVE-1) further revealed the increase in ring (oratretic strip-like) lymphatic vessels in either the peritumoral or intratumoral areas in the HeLa-K group compared with the HeLa-C group. Consistently, the analysis of human cancerous tissue also showed that NOK was highly expressed in the walls of tubular structures. Thus, our results reveal a novel tumorigenic function of NOK to mediate the genesis and remodeling of blood and lymphatic vessels during tumor progression.

  13. NOK/STYK1 promotes the genesis and remodeling of blood and lymphatic vessels during tumor progression.

    Science.gov (United States)

    Liu, Yue; Li, Tianqi; Hu, Dan; Zhang, Shuping

    2016-09-01

    Previous studies have indicated that the overexpression of NOK, also named STYK1, led to tumorigenesis and metastasis. Here, we provide evidence that increased expression of NOK/STYK1 caused marked alterations in the overall and inner structures of tumors and substantially facilitates the genesis and remodeling of the blood and lymphatic vessels during tumor progression. In particular, NOK-expressed HeLa stable cells (HeLa-K) significantly enhanced tumor growth and metastasis in xenografted nude mice. Hematoxylin and eosin (HE) staining demonstrated that the tumor tissues generated by HeLa-K cells were much more ichorous and had more interspaces than those generated by control HeLa cells (HeLa-C). The fluorescent areas stained with cluster of differentiation 31 (CD31), a marker protein for blood vessels, appeared to be in different patterns. The total blood vessels, especially the ring patterns, within the tumors of the HeLa-K group were highly enriched compared with those in the HeLa-C group. NOK-HA was demonstrated to be well colocalized with CD31 in the wall of the tubular structures within tumor tissues. Interestingly, antibody staining of the lymphatic vessel endothelial hyaluronan receptor (LYVE-1) further revealed the increase in ring (oratretic strip-like) lymphatic vessels in either the peritumoral or intratumoral areas in the HeLa-K group compared with the HeLa-C group. Consistently, the analysis of human cancerous tissue also showed that NOK was highly expressed in the walls of tubular structures. Thus, our results reveal a novel tumorigenic function of NOK to mediate the genesis and remodeling of blood and lymphatic vessels during tumor progression. PMID:27444381

  14. A new resorbable device for ligation of blood vessels - A pilot study

    Directory of Open Access Journals (Sweden)

    Borg Niklas

    2011-07-01

    Full Text Available Abstract Background During surgery, controlled haemostasis to prevent blood loss is vital for a successful outcome. It can be difficult to ligate vessels located deep in the abdomen. A device that is easy to use and enables secure ligatures could be beneficial. Cable ties made of nylon have been used for ligation but the non-resorbable material caused tissue reactions. The objective of this study was to use a resorbable material to construct a device with a self-locking mechanism and to test its mechanical strength and ligation efficiency. Methods The device was manufactured by injection moulding of polydioxanone, a resorbable polymer used for suture materials. Polydioxanone with inherent viscosities of 1.9 dL/g and 1.3 dL/g were tested. The device consisted of a perforated flexible band which could be pulled through a case with a locking mechanism. After a first version of the device had been tested, some improvements were made. The locking case was downsized, corners were rounded off, the band was made thicker and the mould was redesigned to produce longer devices. Tensile tests were performed with the second version. The first version of the device was used to ligate the ovarian pedicle in a euthanized dog and to test echogenicity of the device with ultrasound. Compression of vessels of the ovarian pedicle was examined by histology. Both versions of the device were tested for haemostasis of and tissue grip on renal arteries in six anaesthetised pigs. Results The tensile strength of the flexible band of the devices with inherent viscosity of 1.9 dL/g was 50.1 ± 5.5 N (range 35.2-62.9 N, n = 11 and the devices with inherent viscosity of 1.3 dL/g had a tensile strength of 39.8 ± 8.1 N (range 18.6-54.2 N, n = 11. Injection moulding of the polymer with lower inherent viscosity resulted in a longer flow distance. Both versions of the device had an effective tissue grip and complete haemostasis of renal arteries was verified. The device attached

  15. [A new objective clinical method in the evaluation of the status of blood flow in conjunctival vessels].

    Science.gov (United States)

    Polunin, G S; Pirogova, E P; Iarovaia, L D

    1989-01-01

    The suggested method for assessment of the blood aggregation characteristics in the conjunctival vessels is based on microdensitometry of the blood stream microphotographs. The method permits a graphic recording of the blood stream. The potentialities of the developed technique have been studied in comparison of the blood aggregation in patients with diabetic retinopathy and in normal subjects. The data evidence an increased coagulation activity of the blood in patients with diabetes mellitus vs. normal subjects, this correlating with the biochemical findings in examinations of these patients' hemostasis. The clinical method for assessment of the blood aggregation characteristics may be useful for the prognosis of the course of various diseases and for monitoring the treatment efficacy.

  16. An Automated Graphical User Interface based System for the Extraction of Retinal Blood Vessels using Kirsch’s Template

    Directory of Open Access Journals (Sweden)

    Joshita Majumdar

    2015-06-01

    Full Text Available The assessment of Blood Vessel networks plays an important role in a variety of medical disorders. The diagnosis of Diabetic Retinopathy (DR and its repercussions including micro aneurysms, haemorrhages, hard exudates and cotton wool spots is one such field. This study aims to develop an automated system for the extraction of blood vessels from retinal images by employing Kirsch’s Templates in a MATLAB based Graphical User Interface (GUI. Here, a RGB or Grey image of the retina (Fundus Photography is used to obtain the traces of blood vessels. We have incorporated a range of Threshold values for the blood vessel extraction which would provide the user with greater flexibility and ease. This paper also deals with the more generalized implementation of various MATLAB functions present in the image processing toolbox of MATLAB to create a basic image processing editor with different features like noise addition and removal, image cropping, resizing & rotation, histogram adjust, separately viewing the red, green and blue components of a colour image along with brightness control, that are used in a basic image editor. We have combined both Kirsch’s Template and various MATLAB Algorithms to obtain enhanced images which would allow the ophthalmologist to edit and intensify the images as per his/her requirement for diagnosis. Even a non technical person can manage to identify severe discrepancies because of its user friendly appearance. The GUI contains very commonly used English Language viz. Load, Colour Contrast Panel, Image Clarity etc that can be very easily understood. It is an attempt to incorporate maximum number of image processing techniques under one GUI to obtain higher performance. Also it would provide a cost effective solution towards obtaining high definition and resolution images of blood vessel extracted Retina in economically backward regions where costly machine like OCT (Optical Coherence Tomography, MRI (Magnetic Resonance

  17. Evidence of Flicker-Induced Functional Hyperaemia in the Smallest Vessels of the Human Retinal Blood Supply

    Science.gov (United States)

    Bui, Bang V.

    2016-01-01

    Regional changes in blood flow are initiated within neural tissue to help fuel local differences in neural activity. Classically, this response was thought to arise only in larger arterioles and venules. However, recently, it has been proposed that a) the smallest vessels of the circulation make a comparable contribution, and b) the response should be localised intermittently along such vessels, due to the known distribution of contractile mural cells. To assess these hypotheses in human neural tissue in vivo, we imaged the retinal microvasculature (diameters 3–28 μm) non-invasively, using adaptive optics, before and after delivery of focal (360 μm) patches of flickering visible light. Our results demonstrated a definite average response in 35% of all vessel segments analysed. In these responding vessels, the magnitude of proportional dilation (mean ± SEM for pre-capillary arterioles 13 ± 5%, capillaries 31 ± 8%, and post-capillary venules 10 ± 3%) is generally far greater than the magnitudes we and others have measured in the larger retinal vessels, supporting proposition a) above. The dilations observed in venules were unexpected based on previous animal work, and may be attributed either to differences in stimulus or species. Response heterogeneity across the network was high; responses were also heterogeneous along individual vessels (45% of vessel segments showed demonstrable locality in their response). These observations support proposition b) above. We also observed a definite average constriction across 7% of vessel segments (mean ± SEM constriction for capillaries -16 ± 3.2%, and post-capillary venules -18 ± 12%), which paints a picture of dynamic redistribution of flow throughout the smallest vessel networks in the retina in response to local, stimulus-driven metabolic demand. PMID:27617960

  18. Rapid sealing and cutting of porcine blood vessels, ex vivo, using a high-power, 1470-nm diode laser.

    Science.gov (United States)

    Giglio, Nicholas C; Hutchens, Thomas C; Perkins, William C; Latimer, Cassandra; Ward, Arlen; Nau, William H; Fried, Nathaniel M

    2014-03-01

    Suture ligation with subsequent cutting of blood vessels to maintain hemostasis during surgery is time consuming and skill intensive. Energy-based electrosurgical and ultrasonic devices are often used to replace sutures and mechanical clips to provide rapid hemostasis and decrease surgery time. Some of these devices may create undesirably large collateral zones of thermal damage and tissue necrosis, or require separate mechanical blades for cutting. Infrared lasers are currently being explored as alternative energy sources for vessel sealing applications. In a previous study, a 1470-nm laser was used to seal vessels 1 to 6 mm in diameter in 5 s, yielding burst pressures of ∼500  mmHg. The purpose of this study was to provide vessel sealing times comparable with current energy-based devices, incorporate transection of sealed vessels, and demonstrate high vessel burst pressures to provide a safety margin for future clinical use. A 110-W, 1470-nm laser beam was transmitted through a fiber and beam shaping optics, producing a 90-W linear beam 3.0 by 9.5 mm for sealing (400  W/cm2), and 1.1 by 9.6 mm for cutting (1080  W/cm2). A two-step process sealed and then transected ex vivo porcine renal vessels (1.5 to 8.5 mm diameter) in a bench top setup. Seal and cut times were 1.0 s each. A burst pressure system measured seal strength, and histologic measurements of lateral thermal spread were also recorded. All blood vessels tested (n=55 seal samples) were sealed and cut, with total irradiation times of 2.0 s and mean burst pressures of 1305±783  mmHg. Additional unburst vessels were processed for histological analysis, showing a lateral thermal spread of 0.94±0.48  mm (n=14 seal samples). This study demonstrated that an optical-based system is capable of precisely sealing and cutting a wide range of porcine renal vessel sizes and, with further development, may provide an alternative to radiofrequency- and ultrasonic-based vessel sealing devices.

  19. Molecular Dynamics Simulation of Soft Grains: Malaria-Infected Red Blood Cells Motion within Obstructed 2-D Capillary Vessel

    CERN Document Server

    Haris, Luman; Haryanto, Freddy; Viridi, Sparisoma

    2013-01-01

    Molecular dynamics has been widely used to numerically solve equation of motion of classical many-particle system. It can be used to simulate many systems including biophysics, whose complexity level is determined by the involved elements. Based on this method, a numerical model had been constructed to mimic the behaviour of malaria-infected red blood cells within capillary vessel. The model was governed by three forces namely Coulomb force, normal force, and Stokes force. By utilizing two dimensional four-cells scheme, theoretical observation was carried out to test its capability. Although the parameters were chosen deliberately, all of the quantities were given arbitrary value. Despite this fact, the results were quite satisfactory. Combined with the previous results, it can be said that the proposed model were sufficient enough to mimic the malaria-infected red blood cells motion within obstructed capillary vessel. Keywords: molecular dynamics, two-dimensional model, red-blood cell motion, malaria

  20. A study of the influence scan timing and depiction of blood vessel diameter in CE-3DMRA. Simulation by pulsatile flow

    International Nuclear Information System (INIS)

    In imaging using contrast-enhanced three-dimensional magnetic resonance angiography (CE-3DMRA), optimizing the delay time from the start of intravenous injection of contrast medium to the start of scanning has generally been an important concern when obtaining blood vessel images of good contrast. Recent methods of mechanically assessing the attainment of contrast medium injection include Smart-Prep and others. Another method is the Test Bolus, in which a small amount of contrast medium determines the timing of scan start, in quest of the time intensity curve. Because these methods are not necessarily satisfactory, the corrected method is used in clinical cases. In terms of how scan timing affects blood vessel depiction, no study has examined pulsatile flow, which is carried out by simulation. On the other hand, there are reports on data filling of k-space using imitation blood vessels on a computer and simple experimental equipment. This research examined experimentally blood vessel depiction according to scan timing and the diameter of blood vessels by using a systemic circulation simulator that incorporated hemodynamic circulation in which pulsatile flow is the same as that of a human body, using an artificial heart developed especially for MRI. It is thought that scan timing in CE-3DMRA affects the depiction of blood vessels for which the diameter of the blood vessel differs from the experimental result. Phase-encoding k-space data filling is the contrast-to-noise ratio (CNR) of each blood vessel irrespective of sequential and centric k-space ordering. The timing shift phenomenon, in which a blood vessel is so thin that the scan timing is overdue and shows a relatively high value, can occur. Moreover, that scan timing affects not only the diameter of a blood vessel but also depiction of the narrowing of a stenotic blood vessel or a branch blood vessel was demonstrated clinically and experimentally. Therefore, blood vessel depiction changes with scan timing, and

  1. Possible bi-directional link between ETA receptors and protein kinase C in rat blood vessels

    Directory of Open Access Journals (Sweden)

    A. M. Northover

    1995-01-01

    Full Text Available Possible links have been investigated between activation of protein kinase C (PKC and endothelin (ET production by small blood vessels. Perfusion pressures were recorded from rat isolated mesenteric artery, with or without the small intestine attached, before and after addition to the perfusate of either ET-1, ET-3 or the PKC activator 12-deoxyphorbol 13-phenylacetate (DOPPA. Rises in perfusion pressure in response to ET-1 (10−8 Mor DOPPA (10−6 M were reduced significantly by pre-treatment with either the ETA receptor antagonist PD151242 (10−6 M or the PKC inhibitor Ro 31-8220 (10−6 M. ET-3 (10−8 M had a significant, albeit small, effect only when the gut was still attached to the mesentery. Inthis latter preparation ET-1 and DOPPA increased the permeability of villi microvessels to colloidal carbon in the perfusate. This effect of DOPPA was reduced by pre-treatment with either PD151242 or Ro 31-8220, but the effects of ET-1 were reduced significantly only by Ro 31-8220. ET-3 (10−8 M was without effect. The results suggest a possible bi-directional link between ETA receptors and PKC in the intestinal vasculature.

  2. Infrared tomography for diagnostic imaging of port wine stain blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, D. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The objective of this work is the development of Infrared Tomography (IRT) for detecting and characterizing subsurface chromophores in human skin. Characterization of cutaneous chromophores is crucial for advances in the laser treatment of pigmented lesions (e.g., port wine stain birthmarks and tatoos). Infrared tomography (IRT) uses a fast infrared focal plane array (IR-FPA) to detect temperature rises in a substrate induced by pulsed radiation. A pulsed laser is used to produce transient heating of an object. The temperature rise, due to the optical absorption of the pulsed laser light, creates an increase in infrared emission which is measured by the IR-FPA. Although the application of IRT to image subsurface cracks due to metal fatigue is a topic of great interest in the aircraft industry, the application to image subsurface chromophores in biological materials is novel. We present an image recovery method based on a constrained conjugate gradient algorithm that has obtained the first ever high quality images of port wine blood vessels.

  3. Implantable tissue-engineered blood vessels from human induced pluripotent stem cells.

    Science.gov (United States)

    Gui, Liqiong; Dash, Biraja C; Luo, Jiesi; Qin, Lingfeng; Zhao, Liping; Yamamoto, Kota; Hashimoto, Takuya; Wu, Hongwei; Dardik, Alan; Tellides, George; Niklason, Laura E; Qyang, Yibing

    2016-09-01

    Derivation of functional vascular smooth muscle cells (VSMCs) from human induced pluripotent stem cells (hiPSCs) to generate tissue-engineered blood vessels (TEBVs) holds great potential in treating patients with vascular diseases. Herein, hiPSCs were differentiated into alpha-smooth muscle actin (α-SMA) and calponin-positive VSMCs, which were seeded onto polymer scaffolds in bioreactors for vascular tissue growth. A functional TEBV with abundant collagenous matrix and sound mechanics resulted, which contained cells largely positive for α-SMA and smooth muscle myosin heavy chain (SM-MHC). Moreover, when hiPSC-derived TEBV segments were implanted into nude rats as abdominal aorta interposition grafts, they remained unruptured and patent with active vascular remodeling, and showed no evidence of teratoma formation during a 2-week proof-of-principle study. Our studies represent the development of the first implantable TEBVs based on hiPSCs, and pave the way for developing autologous or allogeneic grafts for clinical use in patients with vascular disease. PMID:27336184

  4. Profile of cortisol, glycaemia, and blood parameters of American Bullfrog tadpoles Lithobates catesbeianus exposed to density and hypoxia stressors

    Directory of Open Access Journals (Sweden)

    Patricia C. Teixeira

    2012-12-01

    Full Text Available The aim of this study was to evaluate alterations to the physiological profile (cortisol, glycaemia, and blood parameters of Lithobates catesbeianus caused by the stressors density and hypoxia. The organisms were in the prometamorphosis stage and exposed to different tadpole densities: 1 tadpole/L (T1, 5 tadpoles/L (T2, and 10 tadpoles/L (T3 for 12 days. The blood was collected through the rupture of the caudal blood vessel and collected under normoxia (immediate collection and hypoxia (after 15 minutes of air exposure conditions. Cortisol levels rose on the fourth and eighth days of treatment and returned to basal levels by the end of the experiment. The stressor mechanisms tested did not affect glycaemia. White blood cells (total number of lymphocytes, neutrophils, and eosinophils showed a significant difference at the twelfth day of the experiment when compared with the start of the experiment. We concluded that, under controlled conditions, a density of up to 10 tadpoles/L and air exposure for 15 minutes did not cause harmful physiological alterations during the experimental period. The answer to these stressors maybe was in another hormonal level (corticosterone.

  5. Investigation of source-detector separation optimization for an implantable perfusion and oxygenation sensor for liver blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Justin S [ORNL; Akl, Tony [Texas A& M University; Cote, Gerard L. [Texas A& M University; Wilson, Mark A. [University of Pittsburgh School of Medicine, Pittsburgh PA; Ericson, Milton Nance [ORNL

    2011-01-01

    An implanted system is being developed to monitor transplanted liver health during the critical 7-10 day period posttransplantation. The unit will monitor organ perfusion and oxygen consumption using optically-based probes placed on both the inflow and outflow blood vessels, and on the liver parenchymal surface. Sensing probes are based on a 3- wavelength LED source and a photodiode detector. Sample diffuse reflectance is measured at 735, 805, and 940 nm. To ascertain optimal source-to-photodetector spacing for perfusion measurement in blood vessels, an ex vivo study was conducted. In this work, a dye mixture simulating 80% blood oxygen saturation was developed and perfused through excised porcine arteries while collecting data for various preset probe source-to-photodetector spacings. The results from this study demonstrate a decrease in the optical signal with decreasing LED drive current and a reduction in perfusion index signal with increasing probe spacing. They also reveal a 2- to 4-mm optimal range for blood vessel perfusion probe source-to-photodetector spacing that allows for sufficient perfusion signal modulation depth with maximized signal to noise ratio (SNR). These findings are currently being applied to guide electronic configuration and probe placement for in vivo liver perfusion porcine model studies.

  6. Malformation of certain brain blood vessels caused by TCDD activation of Ahr2/Arnt1 signaling in developing zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Teraoka, Hiroki, E-mail: hteraoka@rakuno.ac.jp [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan); Ogawa, Akira [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan); Kubota, Akira [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan); Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA (United States); Stegeman, John J. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA (United States); Peterson, Richard E. [School of Pharmacy, University of Wisconsin, Madison, WI (United States); Hiraga, Takeo [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan)

    2010-08-15

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes various signs of toxicity in early life stages of vertebrates through activation of the aryl hydrocarbon receptor (AHR). The AHR also plays important roles in normal development in mice, and AHR{sup -/-} mice show abnormal development of vascular structures in various blood vessels. Our previous studies revealed that Ahr type 2 (Ahr2) activation by TCDD and {beta}-naphthoflavone (BNF) caused a significant decrease in blood flow in the dorsal midbrain of zebrafish embryos. Here we report effects of TCDD exposure on the morphology of some blood vessels in the head of developing zebrafish. TCDD caused concentration-dependent anatomical rearrangements in the shape of the prosencephalic artery in zebrafish larvae. In contrast, no major vascular defects were recognized in the trunk and tail regions following exposure to TCDD at least at the concentrations used. Essentially, the same observations were also confirmed in BNF-exposed larvae. Knock-down of either Ahr2 or Ahr nuclear translocator type 1 (Arnt1) by morpholino oligonucleotides (MOs) protected larvae against abnormal shape of the prosencephalic artery caused by TCDD and BNF. On the other hand, knock-down of Ahr2 or Arnt1 in vehicle-exposed zebrafish larvae had no clear effect on morphology of the prosencephalic artery or trunk vessels. Ascorbic acid, an antioxidant, protected against the TCDD-induced decrease in blood flow through the prosencephalic artery, but not the abnormal morphological changes in the shape of this artery. These results indicate that activation of Ahr2/Arnt1 pathway by TCDD and BNF affects the shape of certain blood vessels in the brain of developing zebrafish.

  7. Analysis by NASA's VESGEN Software of Retinal Blood Vessels Before and After 70-Day Bed Rest: A Retrospective Study

    Science.gov (United States)

    Raghunandan, Sneha; Vyas, Ruchi J.; Vizzeri, Gianmarco; Taibbi, Giovanni; Zanello, Susana B.; Ploutz-Snyder, Robert; Parsons-Wingerter, Patricia A.

    2016-01-01

    Significant risks for visual impairment associated with increased intracranial pressure (VIIP) are incurred by microgravity spaceflight, especially long-duration missions. Impairments include decreased near visual acuity, posterior globe flattening, choroidal folds, optic disc edema and cotton wool spots. We hypothesize that microgravity-induced fluid shifts result in pathological changes within the retinal blood vessels that precede development of visual and other ocular impairments. Potential contributions of retinal vascular remodeling to VIIP etiology are therefore being investigated by NASAs innovative VESsel GENeration Analysis (VESGEN) software for two studies: (1) head-down tilt in human subjects before and after 70 days of bed rest, and (2) U.S. crew members before and after ISS missions. VESGEN analysis in previous research supported by the US National Institutes of Health identified surprising new opportunities to regenerate retinal vessels during early-stage, potentially reversible progression of the visually impairing and blinding disease, diabetic retinopathy.

  8. Integrin-α5β1 is not required for mural cell functions during development of blood vessels but is required for lymphatic-blood vessel separation and lymphovenous valve formation.

    Science.gov (United States)

    Turner, Christopher J; Badu-Nkansah, Kwabena; Crowley, Denise; van der Flier, Arjan; Hynes, Richard O

    2014-08-15

    Integrin α5β1 is essential for vascular development but it remains unclear precisely where and how it functions. Here, we report that deletion of the gene encoding the integrin-α5 subunit (Itga5) using the Pdgfrb-Cre transgenic mouse line, leads to oedema, haemorrhage and increased levels of embryonic lethality. Unexpectedly, these defects were not caused by loss of α5 from Pdgfrb-Cre expressing mural cells (pericytes and vascular smooth muscle cells), which wrap around the endothelium and stabilise blood vessels, nor by defects in the heart or great vessels, but were due to abnormal development of the lymphatic vasculature. Reminiscent of the pathologies seen in the human lymphatic malformation, fetal cystic hygroma, α5 mutants display defects both in the separation of their blood and lymphatic vasculature and in the formation of the lymphovenous valves. As a consequence, α5-deficient mice develop dilated, blood-filled lymphatic vessels and lymphatic capillaries that are ectopically covered with smooth muscle cells. Analysis of the expression of Pdgfrb during lymphatic development suggests that these defects probably arise from loss of α5β1 integrin in subsets of specialised Prox1(+)Pdgfrb(+) venous endothelial cells that are essential for the separation of the jugular lymph sac from the cardinal vein and formation of the lymphovenous valve leaflets.

  9. NUMERICAL SIMULATION OF HEMODYNAMICS IN THE HOST BLOOD VESSEL AND MICROVASCULAR NETWORK GENERATED FROM TUMOR-INDUCED ANGIOGENESIS

    Institute of Scientific and Technical Information of China (English)

    ZHAO Gai-ping; WU Jie; XU Shi-xiong; COLLINS M.W.; JIANG Yu-ping; WANG Jian

    2006-01-01

    Numerical simulation of hemodynamics under the combined effects of both the host blood vessel and the microvascular network,which is based on a 2-D tumor inside and outside vascular network generated from a discrete mathematical model of tumor-induced angiogenesis, is performed systemically. And a "microvascular network-transport across microvascular network-flow in interstitium" model is developed to study the flow in solid tumor. Simulations are carried out to examine the effects of the variations of the inlet Reynolds number in the host blood vessel, the hydraulic conductivity of the microvascular wall, and interstitial hydraulic conductivity coefficient on the fluid flow in tumor microcirculation. The results are consistent with data obtained in terms of physiology. These results may provide some theoretical references and the bases for further clinical experimental research.

  10. Imaging functional blood vessels by the laser speckle imaging (LSI) technique using Q-statistics of the generalized differences algorithm.

    Science.gov (United States)

    Ansari, Mohammad Zaheer; Cabrera, Humberto; Ramírez-Miquet, Evelio E

    2016-09-01

    In this work, we report about q statistics concept to improve the performance of generalized differences algorithm based on intensity histogram for imaging functional blood vessel structures in a rodent window chamber of a mice. The method uses the dynamic speckle signals obtained by transilluminating the rodent window chamber to create activity maps of vasculatures. The proposed method of generalized differences with q statistics (GDq) is very sensitive to the values of defined parameters such as: camera exposure time, the q value and the camera frame number. Appropriate choice of q values enhances the visibility (contrast) of functional blood vessels but at the same time without sacrificing the spatial resolution, which is of utmost importance for in-vivo vascular imaging. PMID:27154269

  11. Relation of Blood Pressure to Retinal Vessel Diameter in Type 1 Diabetes Mellitus

    Science.gov (United States)

    Klein, Ronald; Myers, Chelsea E.; Klein, Barbara E. K.; Zinman, Bernard; Gardiner, Robert; Suissa, Samy; Sinaiko, Alan R.; Donnelly, Sandra M.; Goodyer, Paul; Strand, Trudy; Mauer, Michael

    2009-01-01

    Objective To examine the relationship of blood pressure (BP) and use of angiotensin receptor blocker (ARB) or angiotensin converting enzyme inhibitor (ACEI) to retinal vessel diameter in normotensive, normoalbuminuric persons with type 1 diabetes mellitus (T1DM). Design Randomized controlled clinical trial. Participants Persons with T1DM and gradable fundus photographs both at baseline (n=147) and 5-year follow-up (n=124). Methods Clinic and 24-hour ambulatory BPs (ABP) were measured. Retinal arteriolar and venular diameters were measured using a computer-assisted technique. Individual arteriolar and venular measurements were combined into summary indices that reflect the average retinal arteriolar (central retinal arteriolar equivalent [CRAE]) and venular (central retinal venular equivalent [CRVE]) diameter of an eye, respectively. Main Outcome Measures CRAE and CRVE. Results While controlling for age, study site, glycosylated hemoglobin and ambulatory pulse rate, daytime ambulatory systolic (-0.29 μm effect per 1mmHg, P=.02) and daytime ambulatory diastolic (-0.44 μm effect per 1mmHg, P=.04), nighttime ambulatory systolic (-0.27 μm effect per 1mmHg, P=.03), and 24-hour ambulatory systolic BP (-0.31 μm effect per 1mmHg, P=.03) were cross-sectionally associated with a smaller CRAE. While controlling for age, study site, glycosylated hemoglobin, ambulatory pulse rate and baseline CRAE, no BP measure was associated with a change in CRAE or CRVE over 5 years of follow-up. Treatment with losartan or enalapril was not associated with a statistically significant change in CRAE or CRVE. Conclusions ACEI or ARB therapy does not affect retinal arteriolar or venular diameter in normotensive persons with T1DM. PMID:20142543

  12. Biomimetic control of vascular smooth muscle cell morphology and phenotype for functional tissue-engineered small-diameter blood vessels.

    Science.gov (United States)

    Chan-Park, Mary B; Shen, Jin Ye; Cao, Ye; Xiong, Yun; Liu, Yunxiao; Rayatpisheh, Shahrzad; Kang, Gavin Chun-Wei; Greisler, Howard P

    2009-03-15

    Small-diameter blood vessel substitutes are urgently needed for patients requiring replacements of their coronary and below-the-knee vessels and for better arteriovenous dialysis shunts. Circulatory diseases, especially those arising from atherosclerosis, are the predominant cause of mortality and morbidity in the developed world. Current therapies include the use of autologous vessels or synthetic materials as vessel replacements. The limited availability of healthy vessels for use as bypass grafts and the failure of purely synthetic materials in small-diameter sites necessitate the development of a biological substitute. Tissue engineering is such an approach and has achieved promising results, but reconstruction of a functional vascular tunica media, with circumferentially oriented contractile smooth muscle cells (SMCs) and extracellular matrix, appropriate mechanical properties, and vasoactivity has yet to be demonstrated. This review focuses on strategies to effect the switch of SMC phenotype from synthetic to contractile, which is regarded as crucial for the engineering of a functional vascular media. The synthetic SMC phenotype is desired initially for cell proliferation and tissue remodeling, but the contractile phenotype is then necessary for sufficient vasoactivity and inhibition of neointima formation. The factors governing the switch to a more contractile phenotype with in vitro culture are reviewed.

  13. Long-term streptozotocin-induced diabetes in rats leads to severe damage of brain blood vessels and neurons via enhanced oxidative stress.

    Science.gov (United States)

    Yang, Hongying; Fan, Shourui; Song, Dianping; Wang, Zhuo; Ma, Shungao; Li, Shuqing; Li, Xiaohong; Xu, Mian; Xu, Min; Wang, Xianmo

    2013-02-01

    The aim of this study was to investigate pathophysiological alterations and oxidative stress in various stages of streptozotocin (STZ)‑induced diabetes mellitus (DM) in rats. Male Sprague-Dawley rats (120) were randomized into DM and control groups. Body mass, plasma glucose, glycated hemoglobin (HbA1c), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) levels, as well as aldose reductase (AR) activities, in brain tissue and serum were determined. Electron microscopy was used to observe neuron and vessel changes in the brain. In STZ‑treated rats, blood glucose, low density lipoproteins, triglycerides and total cholesterol levels increased 1.43‑3.0‑fold and high density lipoprotein, HbA1c and insulin sensitivity index increased 1.1‑1.23‑fold compared with control. At week 16 following treatment, DM rat serum H2O2 concentration was increased, indicating oxidative stress and mRNA levels of GPx and SOD were 2‑fold higher than the control. Protein GPx and SOD levels were reduced (Pblood vessels in the DM rat brains became increasingly abnormal over time with altered Golgi bodies, mitochondria and endoplasmic reticulum cisterns, concurrent with SOD inactivation and AR protein accumulation. Disease progression in rats with STZ‑induced DM included brain pathologies with vascular and neuron cell abnormalities, associated with the reduction of SOD, CAT and GPx activities and also AR accumulation.

  14. High-density automotive hydrogen storage with cryogenic capable pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Aceves, Salvador M.; Espinosa-Loza, Francisco; Ledesma-Orozco, Elias; Ross, Timothy O.; Weisberg, Andrew H. [Lawrence Livermore National Laboratory, P.O. Box 808, L-792, Livermore, CA 94551 (United States); Brunner, Tobias C.; Kircher, Oliver [BMW Group, Knorrstr. 147, 80788 Munich (Germany)

    2010-02-15

    LLNL is developing cryogenic capable pressure vessels with thermal endurance 5-10 times greater than conventional liquid hydrogen (LH{sub 2}) tanks that can eliminate evaporative losses in routine usage of (L)H{sub 2} automobiles. In a joint effort BMW is working on a proof of concept for a first automotive cryo-compressed hydrogen storage system that can fulfill automotive requirements on system performance, life cycle, safety and cost. Cryogenic pressure vessels can be fueled with ambient temperature compressed gaseous hydrogen (CGH{sub 2}), LH{sub 2} or cryogenic hydrogen at elevated supercritical pressure (cryo-compressed hydrogen, CcH{sub 2}). When filled with LH{sub 2} or CcH{sub 2}, these vessels contain 2-3 times more fuel than conventional ambient temperature compressed H{sub 2} vessels. LLNL has demonstrated fueling with LH{sub 2} onboard two vehicles. The generation 2 vessel, installed onboard an H{sub 2}-powered Toyota Prius and fueled with LH{sub 2} demonstrated the longest unrefueled driving distance and the longest cryogenic H{sub 2} hold time without evaporative losses. A third generation vessel will be installed, reducing weight and volume by minimizing insulation thickness while still providing acceptable thermal endurance. Based on its long experience with cryogenic hydrogen storage, BMW has developed its cryo-compressed hydrogen storage concept, which is now undergoing a thorough system and component validation to prove compliance with automotive requirements before it can be demonstrated in a BMW test vehicle. (author)

  15. Development and application of a volume penalization immersed boundary method for the computation of blood flow and shear stresses in cerebral vessels and aneurysms

    NARCIS (Netherlands)

    Mikhal, Julia; Geurts, Bernard J.

    2013-01-01

    A volume-penalizing immersed boundary method is presented for the simulation of laminar incompressible flow inside geometrically complex blood vessels in the human brain. We concentrate on cerebral aneurysms and compute flow in curved brain vessels with and without spherical aneurysm cavities attach

  16. Angiogenesis and vasculogenesis: inducing the growth of new blood vessels and wound healing by stimulation of bone marrow-derived progenitor cell mobilization and homing.

    Science.gov (United States)

    Velazquez, Omaida C

    2007-06-01

    During embryonic development, the vasculature is among the first organs to form and is in charge of maintaining metabolic homeostasis by supplying oxygen and nutrients and removing waste products. As one would expect, blood vessels are critical not only for organ growth in the embryo but also for repair of wounded tissue in the adult. An imbalance in angiogenesis (a time-honored term that globally refers to the growth of new blood vessels) contributes to the pathogenesis of numerous malignant, inflammatory, ischemic, infectious, immune, and wound-healing disorders. This review focuses on the central role of the growth of new blood vessels in ischemic and diabetic wound healing and defines the most current nomenclature that describes the neovascularization process in wounds. There are now two well-defined, distinct, yet interrelated processes for the formation of postnatal new blood vessels, angiogenesis, and vasculogenesis. Reviewed are recent new data on vasculogenesis that promise to advance the field of wound healing.

  17. [The effect of prostatilen on the contractile activity of the smooth-muscle cells of the blood vessels and bladder in cats].

    Science.gov (United States)

    al-Shchukri, S Kh; Barabanov, S V; Barabanova, V V; Bobkov, Iu A; Gorbachev, A G; Parastaeva, M M

    1996-07-01

    Prostatilene enhanced the functional activity of the bladder and blood vessels' smooth muscle cells. A possibility of activation of the smooth muscle cells contractility with prostatilene by a pharmaco-mechanical association, is discussed.

  18. In-vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography

    Science.gov (United States)

    Yazdanfar, Siavash; Rollins, Andrew M.; Izatt, Joseph A.

    1999-04-01

    Quantification of retinal blood flow may lead to a better understanding of the progression and treatment of several ocular disorders, including diabetic retinopathy, age- related macular degeneration, and glaucoma. Current techniques, such as fluorescein angiography and laser Doppler velocimetry are limited, failing to provide sufficient information to the clinician. Color Doppler optical coherence tomography (CDOCT) is a novel technique using coherent heterodyne detection for simultaneous cross- sectional imaging of tissue microstructure and blood flow. This technique is capable of high spatial and velocity resolution imaging in highly scattering media. We implemented CDOCT for retinal blood flow mapping in human subjects. No dilation of the pupil was necessary. CDOCT is demonstrated for determining bidirectional flow in sub- 100micrometers diameter vessels in the retina. Additionally, we calculated Doppler broadening using the variance of depth- resolved spectra to identify regions with large velocity gradients within the Xenopus heart. This technique may be useful in quantifying local tissue perfusion in highly vascular retinal tissue.

  19. Blood oxygenation level-dependent magnetic resonance imaging during carbogen breathing: differentiation between prostate cancer and benign prostate hyperplasia and correlation with vessel maturity

    Science.gov (United States)

    Di, Ningning; Mao, Ning; Cheng, Wenna; Pang, Haopeng; Ren, Yan; Wang, Ning; Liu, Xinjiang; Wang, Bin

    2016-01-01

    Objective The aim of this study was to investigate whether the blood oxygenation level-dependent (BOLD) contrast magnetic resonance imaging (MRI) can evaluate tumor maturity and preoperatively differentiate prostate cancer (PCa) from benign prostate hyperplasia (BPH). Patients and methods BOLD MRI based on transverse relaxation time*-weighted echo planar imaging was performed to assess PCa (19) and BPH (22) responses to carbogen (95% O2 and 5% CO2). The average signal values of PCa and BPH before and after carbogen breathing and the relative increased signal values were computed, respectively. The endothelial-cell marker, CD31, and the pericyte marker, α-smooth muscle actin (mature vessels), were detected with immunofluorescence, and were assessed by microvessel density (MVD) and microvessel pericyte density (MPD). The microvessel pericyte coverage index (MPI) was used to evaluate the degree of vascular maturity. The changed signal from BOLD MRI was correlated with MVD, MPD, and MPI. Results After inhaling carbogen, both PCa and BPH showed an increased signal, but a lower slope was found in PCa than that in BPH (PMPI than BPH. The increased signal intensity was positively correlated with MPI in PCa and that in BPH (r=0.616, P=0.011; r=0.658, P=0.002); however, there was no correlation between the increased signal intensity and MPD or MVD in PCa than that in BPH (P>0.05). Conclusion Our results confirmed that the increased signal values induced by BOLD MRI well differentiated PCa from BPH and had a positive correlation with vessel maturity in both of them. BOLD MRI can be utilized as a surrogate marker for the noninvasive assessment of the degree of vessel maturity. PMID:27462169

  20. High-Yield Method for Isolation and Culture of Endothelial Cells from Rat Coronary Blood Vessels Suitable for Analysis of Intracellular Calcium and Nitric Oxide Biosynthetic Pathways

    Science.gov (United States)

    Nistri, Silvia; Mazzetti, Luca; Failli, Paola

    2002-01-01

    We describe here a method for isolating endothelial cells from rat heart blood vessels by means of coronary microperfusion with collagenase. This methods makes it possible to obtain high amounts of endothelial cells in culture which retain the functional properties of their in vivo counterparts, including the ability to uptake fluorescently-labeled acetylated low-density lipoproteins and to respond to vasoactive agents by modulating intracellular calcium and by upregulating intrinsic nitric oxide generation. The main advantages of our technique are: (i) good reproducibility, (ii) accurate sterility that can be maintained throughout the isolation procedure and (iii) high yield of pure endothelial cells, mainly due to microperfusion and temperature-controlled incubation with collagenase which allow an optimal distribution of this enzyme within the coronary vascular bed. PMID:12734571

  1. High-Yield Method for Isolation and Culture of Endothelial Cells from Rat Coronary Blood Vessels Suitable for Analysis of Intracellular Calcium and Nitric Oxide Biosynthetic Pathways

    Directory of Open Access Journals (Sweden)

    Nistri Silvia

    2002-01-01

    Full Text Available We describe here a method for isolating endothelial cells from rat heart blood vessels by means of coronary microperfusion with collagenase. This methods makes it possible to obtain high amounts of endothelial cells in culture which retain the functional properties of their in vivo counterparts, including the ability to uptake fluorescently-labeled acetylated low-density lipoproteins and to respond to vasoactive agents by modulating intracellular calcium and by upregulating intrinsic nitric oxide generation. The main advantages of our technique are: (i good reproducibility, (ii accurate sterility that can be maintained throughout the isolation procedure and (iii high yield of pure endothelial cells, mainly due to microperfusion and temperature-controlled incubation with collagenase which allow an optimal distribution of this enzyme within the coronary vascular bed.

  2. The blood-tendon barrier: identification and characterisation of a novel tissue barrier in tendon blood vessels.

    Science.gov (United States)

    Lehner, C; Gehwolf, R; Ek, J C; Korntner, S; Bauer, H; Bauer, H C; Traweger, A; Tempfer, H

    2016-01-01

    Tissue barriers function as "gate keepers" between different compartments (usually blood and tissue) and are formed by specialised membrane-associated proteins, localising to the apicolateral plasma membrane domain of epithelial and endothelial cells. By sealing the paracellular space, the free diffusion of solutes and molecules across epithelia and endothelia is impeded. Thereby, tissue barriers contribute to the establishment and maintenance of a distinct internal and external environment, which is crucial during organ development and allows maintenance of an organ-specific homeostatic milieu. So far, various epithelial and endothelial tissue barriers have been described, including the blood-brain barrier, the blood-retina barrier, the blood-testis barrier, the blood-placenta barrier, and the cerebrospinal fluid (CSF)-brain barrier, which are vital for physiological function and any disturbance of these barriers can result in severe organ damage or even death. Here, we describe the identification of a novel barrier, located in the vascular bed of tendons, which we term the blood-tendon barrier (BTB). By using immunohistochemistry, transmission electron microscopy, and tracer studies we demonstrate the presence of a functional endothelial barrier within tendons restricting the passage of large blood-borne molecules into the surrounding tendon tissue. We further provide in vitro evidence that the BTB potentially contributes to the creation of a distinct internal tissue environment impacting upon the proliferation and differentiation of tendon-resident cells, effects which might be fundamental for the onset of tendon pathologies. PMID:27227787

  3. The use of BDNF to enhance the patency rate of small-diameter tissue-engineered blood vessels through stem cell homing mechanisms.

    Science.gov (United States)

    Zeng, Wen; Wen, Can; Wu, Yangxiao; Li, Li; Zhou, Zhenhua; Mi, Jianhong; Chen, Wen; Yang, Mingcan; Hou, Chunli; Sun, Jiansen; Zhu, Chuhong

    2012-01-01

    The patency rate of small-diameter tissue-engineered blood vessels is the determinant for their application in coronary artery bypass grafting. The coronary artery is innervated by vagus nerves. The origin of vagus nerves is rich in brain-derived neurotrophic factors (BDNF). We have investigated whether BDNF could improve the patency rate of small-diameter tissue-engineered blood vessels through promoting stem cell homing and paracrine activity. In vitro, we isolated early and late endothelial progenitor cells (EPCs) and found BDNF could promote single clone formation and paracrine function of EPCs, and could also induce the proliferation, migration and differentiation of late EPCs. BDNF could enhance the capturing of EPCs in parallel-plate flow chamber. Flow cytometric analysis and laser-scanning confocal microscope showed BDNF could enhance the mobilization and homing of C57BL/6 mouse EPCs after wire injury. Based on it, BDNF was coupled to the lumen surface of the blood vessel matrix material incubated with collagen through SPDP to construct BDNF-modified small-diameter tissue-engineered blood vessel. The blood vessel patency rate was significantly higher than that of control group 8 weeks after implantation in rats and the endothelialization level was superior to control. These results demonstrate that BDNF can effectively improve patency of small-diameter tissue-engineered blood vessels through stem cell homing and paracrine, and it is expected to play an important role in the construction of substitutes for coronary artery bypass grafting.

  4. Effect of blood vessel segmentation on the outcome of electroporation-based treatments of liver tumors.

    Directory of Open Access Journals (Sweden)

    Marija Marčan

    Full Text Available Electroporation-based treatments rely on increasing the permeability of the cell membrane by high voltage electric pulses applied to tissue via electrodes. To ensure that the whole tumor is covered with sufficiently high electric field, accurate numerical models are built based on individual patient anatomy. Extraction of patient's anatomy through segmentation of medical images inevitably produces some errors. In order to ensure the robustness of treatment planning, it is necessary to evaluate the potential effect of such errors on the electric field distribution. In this work we focus on determining the effect of errors in automatic segmentation of hepatic vessels on the electric field distribution in electroporation-based treatments in the liver. First, a numerical analysis was performed on a simple 'sphere and cylinder' model for tumors and vessels of different sizes and relative positions. Second, an analysis of two models extracted from medical images of real patients in which we introduced variations of an error of the automatic vessel segmentation method was performed. The results obtained from a simple model indicate that ignoring the vessels when calculating the electric field distribution can cause insufficient coverage of the tumor with electric fields. Results of this study indicate that this effect happens for small (10 mm and medium-sized (30 mm tumors, especially in the absence of a central electrode inserted in the tumor. The results obtained from the real-case models also show higher negative impact of automatic vessel segmentation errors on the electric field distribution when the central electrode is absent. However, the average error of the automatic vessel segmentation did not have an impact on the electric field distribution if the central electrode was present. This suggests the algorithm is robust enough to be used in creating a model for treatment parameter optimization, but with a central electrode.

  5. A micro-scale simulation of red blood cell passage through symmetric and asymmetric bifurcated vessels

    CERN Document Server

    Wang, Tong; Xing, Zhongwen

    2016-01-01

    Blood exhibits a heterogeneous nature of hematocrit, velocity, and effective viscosity in microcapillaries. Microvascular bifurcations have a significant influence on the distribution of the blood cells and blood flow behavior. This paper presents a simulation study performed on the two-dimensionalmotions and deformation of multiple red blood cells in microvessels with diverging and converging bifurcations. Fluid dynamics and membrane mechanics were incorporated. Effects of cell shape, hematocrit, and deformability of the cell membrane on rheological behavior of the red blood cells and the hemodynamics have been investigated. It was shown that the blood entering the daughter branch with a higher flow rate tended to receive disproportionally more cells. The results also demonstrate that red blood cells in microvessels experienced lateral migration in the parent channel and blunted velocity profiles in both straight section and daughter branches, and this effect was influenced by the shape and the initial posit...

  6. Proliferating cell nuclear antigen, p53 and micro vessel density: Grade II vs. Grade III astrocytoma

    Directory of Open Access Journals (Sweden)

    Malhan Priya

    2010-01-01

    Full Text Available Histological classification and grading are prime procedures in the management of patients with astrocytoma, providing vital data for therapeutic decision making and prognostication. However, it has limitations in assessing biological tumor behavior. This can be overcome by using newer immunohistochemical techniques. This study was carried out to compare proliferative indices using proliferating cell nuclear antigen (PCNA, extent of p53 expression and micro vessel morphometric parameters in patients with low grade and anaplastic astrocytoma. Twenty-five patients, each of grade II and grade III astrocytoma were evaluated using monoclonal antibodies to PCNA, p53 protein and factor VIII related antigen. PCNA, p53-labeling indices were calculated along with micro vessel morphometric analysis using Biovis Image plus Software. Patients with grade III astrocytoma had higher PCNA and p53 labeling indices as compared with grade II astrocytoma (29.14 plus/minus 9.87% vs. 16.84 plus/minus 6.57%, p 0.001; 18.18 plus/minus 6.14% vs. 6.14 plus/minus 7.23%, p 0.001, respectively. Micro vessel percentage area of patients with grade III astrocytoma was also (4.26 plus/minus 3.70 vs. 1.05 plus/minus 0.56, p 0.001, higher along with other micro vessel morphometric parameters. Discordance between histology and one or more IHC parameters was seen in 5/25 (20% of patients with grade III astrocytoma and 9/25 (36% of patients with grade II disease. PCNA and p53 labeling indices were positively correlated with Pearson′s correlation, p less than 0.001 for both. Increased proliferative fraction, genetic alterations and neovascularization mark biological aggressiveness in astrocytoma. Immunohistochemical evaluation scores over meet the challenge of accurate prognostication of this potentially fatal malignancy.

  7. Elliptical local vessel density: a fast and robust quality metric for retinal images

    OpenAIRE

    Giancardo, L.; Abramoff, M.D.; Chaum, E.; Karnowski, T.P.; Meriaudeau, F.; Tobin, K.W.

    2008-01-01

    A great effort of the research community is geared towards the creation of an automatic screening system able to promptly detect diabetic retinopathy with the use of fundus cameras. In addition, there are some documented approaches for automatically judging the image quality. We propose a new set of features independent of field of view or resolution to describe the morphology of the patient's vessels. Our initial results suggest that these features can be used to estimate the image quality i...

  8. Effect of antiprogesterone RU486 on VEGF expression and blood vessel remodeling on ovarian follicles before ovulation.

    Directory of Open Access Journals (Sweden)

    Annunziata Mauro

    Full Text Available BACKGROUND: The success of ovarian follicle growth and ovulation is strictly related to the development of an adequate blood vessel network required to sustain the proliferative and endocrine functions of the follicular cells. Even if the Vascular Endothelial Growth Factor (VEGF drives angiogenesis before ovulation, the local role exerted by Progesterone (P₄ remains to be clarified, in particular when its concentration rapidly increases before ovulation. AIM: This in vivo study was designed to clarify the effect promoted by a P₄ receptor antagonist, RU486, on VEGF expression and follicular angiogenesis before ovulation, in particular, during the transition from pre to periovulatory follicles induced by human Chorionic Gonadotropins (hCG administration. MATERIAL AND METHODS: Preovulatory follicle growth and ovulation were pharmacologically induced in prepubertal gilts by combining equine Chorionic Gonadotropins (eCG and hCG used in the presence or absence of RU486. The effects on VEGF expression were analyzed using biochemical and immunohistochemical studies, either on granulosa or on theca layers of follicles isolated few hours before ovulation. This angiogenic factor was also correlated to follicular morphology and to blood vessels architecture. RESULTS AND CONCLUSIONS: VEGF production, blood vessel network and follicle remodeling were impaired by RU486 treatment, even if the cause-effect correlation remains to be clarified. The P₄ antagonist strongly down-regulated theca VEGF expression, thus, preventing most of the angiogenic follicle response induced by hCG. RU486-treated follicles displayed a reduced vascular area, a lower rate of endothelial cell proliferation and a reduced recruitment of perivascular mural cells. These data provide important insights on the biological role of RU486 and, indirectly, on steroid hormones during periovulatory follicular phase. In addition, an in vivo model is proposed to evaluate how periovulatory

  9. FUCOIDIN INHIBITS OXIDIZED LOW DENSITY LIPOPROTEIN FROM INDUCING HUMAN PERIPHERAL BLOOD MONOCYTE EXPRESSION OF PROINFLAMMATORY CYTOKINES mRNA

    Institute of Scientific and Technical Information of China (English)

    雷新军; 马爱群; 任冰稳; 耿涛; 张葳; 白玲

    2003-01-01

    Objective To study the significance of scavenger receptor class A(SR-A)in mediating human peripheral blood monocyte to uptake oxidized low density lipoprotein(OxLDL) and promoting the atherosclerotic immuno-pathological lesion in the local blood vessel. Methods With the Digoxenin-labeled Oligonucleotide-probes In situ Hybridization, this research investigated the effects of OxLDL on the mRNA expression of proinflammatory cytokines including MCP-1, bFGF, PDGF and IL-10 in the human peripheral blood monocyte and whether fucoidin, a peculiarly inhibitory ligand for SR-A, would influence this process. Results Monocyte was significantly increased the mRNA expression of MCP-1, bFGF, PDGF and IL-10 in a dose-dependent manner after incubating with OxLDL (10,15,20,25,30·mg·L-1, respectively)for 24 hours(P<0.001). Fucoidin(50,100,150,200,250·mg·mL-1, respectively)completely inhibited OxLDL(20·mg·L-1)from inducing monocyte the mRNA expression of above proinflammatory cytokines(P<0.001). Conclusion OxLDL can stimulate human peripheral blood monocyte to give expression to proinflammatory cytokines mRNA in a dose-dependent manner, while a peculiarly inhibitory ligand for SR-A-fucoidin has an obviously opposed role.

  10. Hypoxia-inducible factor and vascular endothelial growth factor in the neuroretina and retinal blood vessels after retinal ischemia

    DEFF Research Database (Denmark)

    Håkansson, Gisela; Gesslein, Bodil; Gustafsson, Lotta;

    2010-01-01

    Retinal ischemia arises from circulatory failure. As the retinal blood vessels are key organs in circulatory failure, our aim was to study the retinal vasculature separately from the neuroretina to elucidate the role of hypoxia-inducible factor (HIF) 1α and 1β and vascular endothelial growth factor...... (VEGF) in retinal ischemia. Retinal ischemia was induced in porcine eyes by applying an intraocular pressure, followed by 12 h of reperfusion. HIF-1α mRNA expression was not affected by ischemia, while immunofluorescence staining was higher after ischemia in the neuroretina. HIF-1β immunoreactivity...

  11. Oxidative injury to blood vessels and glia of the pre-laminar optic nerve head in human glaucoma.

    Science.gov (United States)

    Feilchenfeld, Zac; Yücel, Yeni H; Gupta, Neeru

    2008-11-01

    Glaucoma is a leading cause of irreversible world blindness. Oxidative damage and vascular injury have been implicated in the pathogenesis of this disease. The purpose of this study was to determine in human primary open angle glaucoma whether oxidative injury occurs in pre-laminar optic nerve blood vessels and glial cells. Following IRB approval, sections from post-mortem primary open angle glaucoma eyes (n=5) with mean age of 77 +/- 9 yrs (+/-SD) were compared to normal control eyes (n=4) with mean age 70 +/- 9 yrs (Eye Bank of Canada). Immunostaining with nitrotyrosine, a footprint for peroxynitrite-mediated injury, was performed and sections were double-labeled with markers for vascular endothelial cells, perivascular smooth muscle cells, and astrocytes with CD34, smooth muscle actin (SMA), and glial fibrillary acidic protein (GFAP), respectively. Immunostaining was captured in a masked fashion using confocal microscopy, and defined regions of interest for blood vessels and glial tissue. Intensity measurements of supra-threshold area in pixels as percent of the total number of pixels were calculated using ImageJ (NIH) and compared using two-tailed Mann-Whitney nonparametric tests between glaucoma and control groups. Colocalization coefficients with cell-specific markers were determined and compared with random coefficients of correlation. Increased nitrotyrosine immunoreactivity was observed in pre-laminar optic nerve head blood vessels of primary open angle glaucoma eyes compared to controls and this difference was statistically significant (1.35 +/- 1.11% [+/-SD] vs. 0.01 +/- 0.01%, P=0.016). NT-immunoreactivity was also increased in the glial tissue surrounding the pre-laminar optic nerve head in the glaucoma group and compared to controls, and this difference was statistically significant (18.37 +/-12.80% vs. 0.08 +/- 0.04%, P=0.016). Colocalization studies demonstrated nitrotyrosine staining in vascular endothelial and smooth muscle cells, in addition to

  12. Effectiveness of Visualisations for Detection of Errors in Segmentation of Blood Vessels

    NARCIS (Netherlands)

    Schooten, van B.W.; Dijk, van E.M.A.G.; Suinesiaputra, A.; Reiber, J.H.C.

    2010-01-01

    Vascular disease diagnosis often requires a precise segmentation of the vessel lumen. When 3D (Magnetic Resonance Angiography, MRA, or Computed Tomography Angiography, CTA) imaging is available, this can be done automatically, but occasional errors are inevitable. So, the segmentation has to be chec

  13. Biophysical Properties of Scaffolds Modulate Human Blood Vessel Formation from Circulating Endothelial Colony-Forming Cells

    Science.gov (United States)

    Critser, Paul J.; Yoder, Mervin C.

    A functional vascular system forms early in development and is continually remodeled throughout the life of the organism. Impairment to the regeneration or repair of this system leads to tissue ischemia, dysfunction, and disease. The process of vascular formation and remodeling is complex, relying on local microenvironmental cues, cytokine signaling, and multiple cell types to function properly. Tissue engineering strategies have attempted to exploit these mechanisms to develop functional vascular networks for the generation of artificial tissues and therapeutic strategies to restore tissue homeostasis. The success of these strategies requires the isolation of appropriate progenitor cell sources which are straightforward to obtain, display high proliferative potential, and demonstrate an ability to form functional vessels. Several populations are of interest including endothelial colony-forming cells, a subpopulation of endothelial progenitor cells. Additionally, the development of scaffolds to deliver and support progenitor cell survival and function is crucial for the formation of functional vascular networks. The composition and biophysical properties of these scaffolds have been shown to modulate endothelial cell behavior and vessel formation. However, further investigation is needed to better understand how these mechanical properties and biophysical properties impact vessel formation. Additionally, several other cell populations are involved in neoangiogenesis and formation of tissue parenchyma and an understanding of the potential impact of these cell populations on the biophysical properties of scaffolds will also be needed to advance these strategies. This chapter examines how the biophysical properties of matrix scaffolds can influence vessel formation and remodeling and, in particular, the impact on in vivo human endothelial progenitor cell vessel formation.

  14. 基于DLA模型的人体血管生长模拟方法%Simulation Method of Human Blood Vessel Growth Based on DLA Model

    Institute of Scientific and Technical Information of China (English)

    王素; 吴梦天; 张珣; 夏斌; 徐亮

    2016-01-01

    Currently the generating methods of blood vessel structure are from the trunk to the branch, which is incompatible with the blood vessels growth in natural state and leads to some differences in the construction of human blood vessel model. This paper proposes a fractal algorithm for simulation of human blood vessel growth, namely diffusion-limited aggregation model (DLA) based simulation of human blood vessel growth. Firstly, combining fractal algorithm with constrained optimization, the paper establishes a natural growth method of blood vessel curves with directed motion and Brownian motion; and then generates blood vessel curve structure by using the deterministic zero-sided L system (D0L), simulates, in the manner from branch to trunk, the fractal graphics condensed mostly in the natural state, which makes the generated blood vessel model more realistic in structure compared with the blood vessel in natural growth. The experiment and analysis with simulated blood vessel growth show that the algorithm is feasible and the precision is guaranteed.%针对现有研究血管曲线结构生成方法均是从主干到支干的形式,与血管自然生长不符,导致构建的人体血管模型与实际生长结构存在一定差异的局限性的问题,提出一种模拟人体血管生长的分形算法,即基于受限扩散凝聚(DLA)模型的人体血管生长模拟算法.首先结合分形算法与约束构建优化方法的特点,建立兼具布朗运动与定向运动的血管曲线自然生长方法;然后运用分形算法中的确定型林氏无关系统(D0L)生成血管曲线结构,以支干生成主干的方式模拟大量自然状态下凝聚而成的分形图形,使构建的血管模型逼真自然血管的生长结构特性.对模拟血管的生长实验与分析结果表明,该算法具有可行性且精度得到保证.

  15. Elliptical Local Vessel Density: a Fast and Robust Quality Metric for Fundus Images

    Energy Technology Data Exchange (ETDEWEB)

    Giancardo, Luca [ORNL; Chaum, Edward [ORNL; Karnowski, Thomas Paul [ORNL; Meriaudeau, Fabrice [ORNL; Tobin Jr, Kenneth William [ORNL; Abramoff, M.D. [University of Iowa

    2008-01-01

    A great effort of the research community is geared towards the creation of an automatic screening system able to promptly detect diabetic retinopathy with the use of fundus cameras. In addition, there are some documented approaches to the problem of automatically judging the image quality. We propose a new set of features independent of Field of View or resolution to describe the morphology of the patient's vessels. Our initial results suggest that they can be used to estimate the image quality in a time one order of magnitude shorter respect to previous techniques.

  16. Simulation of one-dimensional blood flow in networks of human vessels using a novel TVD scheme.

    Science.gov (United States)

    Huang, P G; Muller, L O

    2015-05-01

    An extension of a total variation diminishing (TVD) scheme to solve one-dimensional (1D) blood flow for human circulation is proposed. This method is simple as it involves only a few modifications to existing shock-capturing TVD schemes. We have applied the method to a wide range of test cases including a complete simulation of the human vascular network. Excellent solutions have been demonstrated for problems involving varying and discontinuous mechanical properties of blood vessels. For 1D network simulations, the method has been shown to agree well with the reported computational results. Finally, the method has been demonstrated to compare favorably with in vivo experiments set up to study the impact of circle of Willis anomalies on flow patterns in the cerebral arterial system. PMID:25529823

  17. At-vessel mortality and blood biochemical status of elasmobranchs caught in an Australian commercial longline fishery

    Directory of Open Access Journals (Sweden)

    Paul A. Butcher

    2015-01-01

    Full Text Available This study investigates mortality of sharks in a commercial longline fishery in Australia. To examine the rate and biological, environmental and technological factors contributing to at-vessel mortality, four setlines with 120 gangions possessing ‘hook timers’ were deployed daily (for 7h and 14h using conventional gears from two commercial fishing vessels during 2013. A total of 689 animals across 22 species and including 18 elasmobranchs were landed. For the five species (Carcharhinus spp., and one genus (Sphyrna spp where there were sufficient numbers for analysis, generalised linear mixed models showed that species and the elapsed time spent on the line after hooking were the strongest predictors of at-vessel mortality, with spinner (Carcharhinus brevipinna, blacktip (C. limbatus and hammerhead (Sphyrna spp sharks exhibiting the highest death rates. The variables which best explained mortality, included: (i sex of the caught sharks, and the interaction between species with (ii capture depth, and (iii the elapsed time spent on the line after hooking. For the subset of dusky (C. obscurus and sandbar (C. plumbeus sharks examined for physiological status at the point of capture, very few of the 13 chosen blood analytes varied significantly. Given the observed high mortality rates and stress associated with the time spent on the line after capture, operational changes to reduce these adverse impacts should be considered. Even simple changes such as shorter soak times could considerably mitigate these impacts.

  18. Pulsatile magneto-hydrodynamic blood flows through porous blood vessels using a third grade non-Newtonian fluids model.

    Science.gov (United States)

    Akbarzadeh, Pooria

    2016-04-01

    In this paper, the unsteady pulsatile magneto-hydrodynamic blood flows through porous arteries concerning the influence of externally imposed periodic body acceleration and a periodic pressure gradient are numerically simulated. Blood is taken into account as the third-grade non-Newtonian fluid. Besides the numerical solution, for small Womersley parameter (such as blood flow through arterioles and capillaries), the analytical perturbation method is used to solve the nonlinear governing equations. Consequently, analytical expressions for the velocity profile, wall shear stress, and blood flow rate are obtained. Excellent agreement between the analytical and numerical predictions is evident. Also, the effects of body acceleration, magnetic field, third-grade non-Newtonian parameter, pressure gradient, and porosity on the flow behaviors are examined. Some important conclusions are that, when the Womersley parameter is low, viscous forces tend to dominate the flow, velocity profiles are parabolic in shape, and the center-line velocity oscillates in phase with the driving pressure gradient. In addition, by increasing the pressure gradient, the mean value of the velocity profile increases and the amplitude of the velocity remains constant. Also, when non-Newtonian effect increases, the amplitude of the velocity profile. PMID:26792174

  19. Measuring density and compressibility of white blood cells and prostate cancer cells by microchannel acoustophoresis

    DEFF Research Database (Denmark)

    Barnkob, Rune; Augustsson, Per; Magnusson, Cecilia;

    2011-01-01

    to determine the density and compressibility of individual cells enables the prediction and alteration of the separation outcome for a given cell mixture. We apply the method on white blood cells (WBCs) and DU145 prostate cancer cells (DUCs) aiming to improve isolation of circulating tumor cells from blood......, an emerging tool in the monitoring and characterizing of metastatic cancer....

  20. Effect of gravitation stress and hypokinesia on blood vessels of the testicle

    Science.gov (United States)

    Palazhchenko, E. F.

    1979-01-01

    Rabbits were exposed to single maximum endurable stresses of cranio-caudal direction, hypokinesia for periods of one to eight weeks, and hypokinesia followed by gravitation stresses. The stresses caused dilatation of vessels, greater sinuosity, and occasional ruptures of the walls and extravasation. The greater part of the capillaries were dilated; the greatest part constricted. In hypokinesia there was an increasing atrophy of the testes. Significant results are reported.

  1. The effect of maternal malnutrition during lactation on the endometrial ERalpha expression, collagen type, and blood vessels in the rats offspring at puberty.

    Science.gov (United States)

    Bittencourt Brasil, Flávia; Silva Faria, Tatiane; Barcellos Sampaio, Francisco José; da Fonte Ramos, Cristiane

    2010-01-01

    The aim of this manuscript was to evaluate the effects of maternal protein-energy-restriction and energy restriction during lactation on endometrial collagen and blood vessels, uterus Eralpha expression, and estradiol serum levels in the rats offspring at puberty. At parturition, dams were grouped as: control group (C), with free access to standard rat chow containing 23% protein and 17,038.7 KJ/Kg; protein-energy restricted group (PER), with free access to formulated chow containing 8% protein but made isoenergetic to the C diet (17,038.7 KJ/Kg); and energy-restricted group (ER), which received standard rat chow containing 23% protein based on the mean ingestion of the PER group corresponding to 60% of that consumed by the control group. After weaning, all female pups had free access to standard laboratory chow until puberty, when they were killed at the diestrum stage. The uterine ERalpha expression was determined by Western-Blot and estradiol serum levels by radioimmunoassay. Endometrial collagen and blood vessels were quantified by stereology. The volumetric density of blood vessels (C = 70.7 +/- 2.2; PER = 29.2 +/- 2.4; ER = 32.3 +/- 3.6; P < 0.001) and endometrial collagen (C = 31.1 +/- 1; PER = 26.9 +/- 1.0; ER = 26.5 +/- 0.7; P < 0.05) were significantly reduced in both malnourished groups. The ER group presented higher estradiol serum levels (C = 69.2 +/- 6.4; PER = 73.4 +/- 5.5; ER = 101.0 +/- 5.4; P < 0.01) in relation to C and PER groups. ERalpha expression was greater in both malnourished groups (C = 0.11 +/- 0.02; PER = 0.41 +/- 0.12; ER = 0.35 +/- 0.03; P < 0.05). In conclusion, maternal malnutrition during lactation caused changes in endometrial angiogenesis, collagen deposition, and Eralpha expression in female offspring that will appear in puberty and could affect the reproductive biology of the female offspring.

  2. Automated detection of kinks from blood vessels for optic cup segmentation in retinal images

    Science.gov (United States)

    Wong, D. W. K.; Liu, J.; Lim, J. H.; Li, H.; Wong, T. Y.

    2009-02-01

    The accurate localization of the optic cup in retinal images is important to assess the cup to disc ratio (CDR) for glaucoma screening and management. Glaucoma is physiologically assessed by the increased excavation of the optic cup within the optic nerve head, also known as the optic disc. The CDR is thus an important indicator of risk and severity of glaucoma. In this paper, we propose a method of determining the cup boundary using non-stereographic retinal images by the automatic detection of a morphological feature within the optic disc known as kinks. Kinks are defined as the bendings of small vessels as they traverse from the disc to the cup, providing physiological validation for the cup boundary. To detect kinks, localized patches are first generated from a preliminary cup boundary obtained via level set. Features obtained using edge detection and wavelet transform are combined using a statistical approach rule to identify likely vessel edges. The kinks are then obtained automatically by analyzing the detected vessel edges for angular changes, and these kinks are subsequently used to obtain the cup boundary. A set of retinal images from the Singapore Eye Research Institute was obtained to assess the performance of the method, with each image being clinically graded for the CDR. From experiments, when kinks were used, the error on the CDR was reduced to less than 0.1 CDR units relative to the clinical CDR, which is within the intra-observer variability of 0.2 CDR units.

  3. Treatment of radiation exposure and regeneration medicine. Regeneration treatment of blood vessels by transplantation of autologous marrow monocytes

    International Nuclear Information System (INIS)

    Described are usefulness and future view of regenerative medicine in the treatment of radiation exposure as exemplified by the vascular regeneration by autologous marrow cell transplantation. Vascular endothelial cells (VEC), possessing a high ability to divide, are known sensitive to radiation, which gives damage of blood vessel to alter its permeability leading to apoptosis of VEC, organ/tissue injuries and final damages in the cerebral blood vessels, central nervous system and skin, the acute radiation syndrome (ARS). Authors present successful cases of patients with chronic limb ischemia in the Therapeutic Angiogenesis using Cell Transplantation Trial (TACT), to whom the treatment is conducted with transplantation of autologous marrow monocyte fraction containing endothelial progenitor cells that differentiate to VEC. As well, they touch on a case of the patient encountered in a nuclear accident, mentioning that VEC are found partly derived from the donor after heamatopoietic stem cell transplantation (HSCT). Efficacy of HSCT in a literature is reviewed and commented to be an only limited one in 31 patients of various radiation accidents. However, treatment of ARS where stem cells are target, with regenerative medicine will become more useful in future, as basic and clinical researches will provide requisite findings. (T.I.)

  4. VEGF signalling controls GnRH neuron survival via NRP1 independently of KDR and blood vessels.

    Science.gov (United States)

    Cariboni, Anna; Davidson, Kathryn; Dozio, Elena; Memi, Fani; Schwarz, Quenten; Stossi, Fabio; Parnavelas, John G; Ruhrberg, Christiana

    2011-09-01

    Gonadotropin-releasing hormone (GnRH) neurons are neuroendocrine cells that are born in the nasal placode during embryonic development and migrate through the nose and forebrain to the hypothalamus, where they regulate reproduction. Many molecular pathways that guide their migration have been identified, but little is known about the factors that control the survival of the migrating GnRH neurons as they negotiate different environments. We previously reported that the class 3 semaphorin SEMA3A signals through its neuropilin receptors, NRP1 and NRP2, to organise the axons that guide migrating GnRH neurons from their birthplace into the brain. By combining analysis of genetically altered mice with in vitro models, we show here that the alternative neuropilin ligand VEGF164 promotes the survival of migrating GnRH neurons by co-activating the ERK and AKT signalling pathways through NRP1. We also demonstrate that survival signalling relies on neuronal, but not endothelial, NRP1 expression and that it occurs independently of KDR, the main VEGF receptor in blood vessels. Therefore, VEGF164 provides survival signals directly to developing GnRH neurons, independently of its role in blood vessels. Finally, we show that the VEGF164-mediated neuronal survival and SEMA3A-mediated axon guidance cooperate to ensure that migrating GnRH neurons reach the brain. Thus, the loss of both neuropilin ligands leads to an almost complete failure to establish the GnRH neuron system.

  5. Correlation of caveolin-1 expression with microlymphatic vessel density in colorectal adenocarcinoma tissues and its correlation with prognosis

    Institute of Scientific and Technical Information of China (English)

    Jun; Xue; Xue-Liang; Wu; Xian-Tao; Huang; Fei; Guo; Hong-Feng; Yu; Peng-Cheng; Zhang; Li-Kun; Wang; Ming; Qu; Li-Ming; Pan

    2015-01-01

    Objective: To study the expression of caveolin-1 in colorectal adenocarcinoma tissues and its correlation with microlymphatic vessel density(LMVD), and to investigate the clinical pathological prognostic significance of caveolin-1 and LMVD in patients with colorectal cancer. Methods: The expression of caveolin-1 and LMVD in 45 specimens of normal colorectal tissues, and 90 specimens of colorectal adenocarcinoma tissues were detected by immunohistochemistry technique. The correlation between their expression and the clinicopathologic features was analyzed. Muhivariable Cox regression was used to analyze the association between the laboratory indices and overall survival time. Results: The positive rates of caveolin-1 in colorectal adenocarcinoma tissues were significantly higher than those in normal colorectal tissues(P<0.01). LMVD in colorectal adenocarcinoma tissues were significantly higher than those in normal colorectal tissues(P<0.01). Mean LMVD in group with caveolin-1 positive was significantly higher than in that with caveolin-1 negative. The median survival time was 26.7 months. Cox regression analysis showed that the caveolin-1 expression, invation depth, lymph nodemetastasis, TNM stage, liver metastasis and LMVD were independent risk factors of overall survival time of patients with colorectal carcinoma. Conclusions: Caveolin-1 may contribute to the lymphangiogenesis in the tumor. During the occurrence and development of colorectal adenocarcinoma, there is a close relationship between the expression of caveolin-1 and lymphatic microvessel of tumor. Caveolin-1 expression and microlymphatic vessel density are significant prognostic value of colorectal carcinoma.

  6. Computational blood flow and vessel wall modeling in a CT-based thoracic aorta after stent-graft implantation

    Science.gov (United States)

    Hazer, Dilana; Stoll, Markus; Schmidt, Eduard; Richter, Goetz-M.; Dillmann, Rüdiger

    2010-03-01

    Abnormal blood flow conditions and structural fatigue within stented vessels may lead to undesired failure causing death to the patient. Image-based computational modeling provides a physical and realistic insight into the patientspecific biomechanics and enables accurate predictive simulations of development, growth and failure of cardiovascular diseases as well as associated risks. Controlling the efficiency of an endovascular treatment is necessary for the evaluation of potential complications and predictions on the assessment of the pathological state. In this paper we investigate the effects of stent-graft implantation on the biomechanics in a patient-specific thoracic aortic model. The patient geometry and the implanted stent-graft are obtained from morphological data based on a CT scan performed during a controlling routine. Computational fluid dynamics (CFD) and computational structure mechanics (CSM) simulations are conducted based on the finite volume method (FVM) and on the finite element method (FEM) to compute the hemodynamics and the elastomechanics within the aortic model, respectively. Physiological data based on transient pressure and velocity profiles are used to set the necessary boundary conditions. Further, the effects of various boundary conditions and definition of contact interactions on the numerical stability of the blood flow and the vessel wall simulation results are also investigated. The quantification of the hemodynamics and the elastomechanics post endovascular intervention provides a realistic controlling of the state of the stented vessel and of the efficiency of the therapy. Consequently, computational modeling would help in evaluating individual therapies and optimal treatment strategies in the field of minimally invasive endovascular surgery.

  7. Usefulness of dilated blood vessels in the tumor periphery for assessing the invasion depth of small-sized depressed colorectal cancer.

    Science.gov (United States)

    Hashimoto, Rintaro; Matsuda, Tomoki; Hamamoto, Hidetaka; Yamaoka, Hajime; Nakahori, Masato; Chonan, Akimichi

    2016-06-01

    The relationship between dilated blood vessels in the tumor periphery and the tumor invasion depth is unclear. Therefore, the present study aimed to clarify the relationship between dilated blood vessels and the invasion depth of small-sized (<30 mm) colorectal cancer (CRC), and its implications on endoscopic treatment.We performed a single-arm observational study of the diagnostic accuracy of the existence of dilated vessels in the tumor periphery of CRC lesions as an indicator of submucosal deep (SM-d, ≥1000 μm) carcinomas. Lesions were classified into two groups based on the existence of dilated vessels by two experienced endoscopists. The clinicopathological features, invasion depth, and lymphovascular invasion/poorly differentiated clusters were analyzed in all resected specimens.Four hundred and two consecutive small-sized CRC lesions were included. The dilated vessels were observed in 96/402 (24%) lesions, and most of them (93/96) were found in depressed lesions. In depressed lesions, the histopathological diagnosis of the dilated vessels group showed SM-d or deeper invasion in 84/93 (90%) cases, whereas 3/20 (15%) had SM-d invasion in the nondilated vessels group (P < 0.001). When the dilated vessels were used as an indicator of SM-d or deeper invasion in depressed lesions, the sensitivity was 95.6%, specificity was 66.7%, and accuracy was 90.2%. No correlation was observed between the existence of dilated vessels and the lesion site, lesion diameter, and lymphovascular invasion/poorly differentiated cluster.The existence of dilated blood vessels in the tumor periphery suggests SM-d or deeper invasion in depressed lesions.

  8. Synthetic reconstruction of dynamic blood flow in cortical arteries using optical coherence tomography for the evaluation of vessel compliance

    Science.gov (United States)

    Baraghis, Edward; Bolduc, Virginie; Gillis, Marc-Antoine; Srinivasan, Vivek J.; Thorin, Éric; Boudoux, Caroline; Lesage, Frédéric

    2011-03-01

    Optical Coherence Tomography (OCT) has recently been used to produce 3D angiography of microvasculature in the rodent brain in-vivo and blood flow maps of large vessels. Key enabling developments were novel algorithms for detecting Doppler shifts produced by moving scatterers and new scanning protocols tailored to increase sensitivity to small flow speeds. These progresses were pushed by the need for a non invasive imaging modality to monitor quantitative blood flow at a higher resolution and a greater depth than could be achieved by other means. The rationale for this work originates from new hypotheses regarding the role of blood regulation in neurodegenerative diseases and from current investigations of animal models of vascular degeneration. In this work we demonstrate the synthetic reconstruction of dynamic blood flow in mice over the course of a single cardiac cycle in an 800μm wide by ~ 3mm deep B-Frame slice with a lateral resolution of 10μm and a depth resolution of 7μm. Images were taken using a cranial window over the exposed parietal bone of mice skull. Electrocardiography (ECG) recordings were co registered with the OCT A lines at high temporal resolution. QRS peak detection was then used to locate the time value of each A-line in the cardiac cycle and to reconstruct a synthetic temporal frame over one cardiac cycle. Doppler speed in this cardiac cycle was used to measure temporal variations of flow inside arteries and of their area. Three dimensional volume scans yielded measurements of quantitative blood flow on the same arteries. Using these informations a measure of compliance could be established. Comparing measures between atherosclerotic (ATX) and wild type (WT) mice revealed higher blood flow in WT mice, suggested lower systemic compliance in the ATX group but higher compliance of cerebral vasculature on these mice. These results are consistent with expectations showing that OCT is a potential tool for in-vivo arterial compliance evaluation.

  9. C-reactive protein and chitinase 3-like protein 1 as biomarkers of spatial redistribution of retinal blood vessels on digital retinal photography in patients with diabetic retinopathy.

    Science.gov (United States)

    Cekić, Sonja; Cvetković, Tatjana; Jovanović, Ivan; Jovanović, Predrag; Pesić, Milica; Stanković Babić, Gordana; Milenković, Svetislav; Risimić, Dijana

    2014-08-20

    The aim of the study was to investigate the correlation between the levels of C-reactive protein (CRP) and chitinase 3-like protein 1 (YKL-40) in blood samples with morpohometric parameters of retinal blood vessels in patients with diabetic retinopathy. Blood laboratory examination of 90 patients included the measurement of glycemia, HbA1C, total cholesterol, LDL-C, HDL-C, triglycerides and CRP. Levels of YKL-40 were detected and measured in serum by ELISA (Micro VueYKL-40 EIA Kit, Quidel Corporation, San Diego, USA). YKL-40 correlated positively with diameter and negatively with number of retinal blood vessels. The average number of the blood vessels per retinal zone was significantly higher in the group of patients with mild non-proliferative diabetic retinopathy than in the group with severe form in the optic disc and all five retinal zones. The average outer diameter of the evaluated retinal zones and optic disc vessels was significantly higher in the group with severe compared to the group with mild diabetic retinopathy. Morphological analysis of the retinal vessels on digital fundus photography and correlation with YKL-40 may be valuable for the follow-up of diabetic retinopathy.

  10. Graphical User Interface (GUI In MatLab for Solving The Pulsatile Flow in Blood Vessel

    Directory of Open Access Journals (Sweden)

    badreddin giuma elghariani

    2009-08-01

    Full Text Available

    Abstract

     

    Blood flow analysis is a study of measuring the blood pressure and finding its equivalent flow rate, velocity profile and wall shear stress. In this article, we determined the relationship between blood pressure gradient, velocity profile, centerline velocity, volumetric flow rate and wall shear stress analytically  through a Graphical User Interface (GUI. If one of these time-dependent blood flow properties is known, i.e. pressure gradient, velocity profile, volumetric flow rate or wall shear stress, then the remaining properties can be calculated. We developed a code to solve these blood flow properties. Any time-dependent blood properties can be used as  input data. These data are then digitized and saved in our code. Subsequently, these data are curve-fitted using the Fourier series. The corresponding coefficients of Fourier series are then used to calculate the blood property. Once this is obtained, the remaining three other flow properties can be subsequently calculated. This GUI serves as a learning tool for  students who wish to pursue his/her knowledge in understanding the relationship of various blood flow properties of pulsatile blood flow as well as the mathematics governing pulsatile flows.

  11. C - reactive protein and chitinase 3-like protein 1 as biomarkers of spatial redistribution of retinal blood vessels on digital retinal photography in patients with diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Sonja Predrag Cekic

    2014-08-01

    Full Text Available The aim of the study was to investegate the correlation between the levels of CRP and YKL-40 in blood samples with morphometric parameters of retinal blood vessels in patients with diabetic retinopathy.Blood laboratory examination of 90 patients included the measurement of glycemia, HbA1C, total cholesterol, LDL-C, HDL-C, triglycerides and CRP. Levels of YKL-40 were detected and measured in serum by ELISA (Micro VueYKL-40 EIA Kit, Quidel Corporation, San Diego, USA.Morphmetric analysis was performed with ImageJ software (http://rsbweb.nih.gov/ij/ for digital retinal photography. We measured the number, diameter of retinal blood vessels in five different parts concentric to the optic disc. Differences between the morphometric parameters and the blood test analysis results were evaluated using the Student’s t – test. One Way ANOVA was used to establish the significance of differences.CRP and YKL-40 levels were moderately higher in the group of patients with severe diabetic retinopathy. Levels of YKL-40 correlated positively with diameter and negatively with number of retinal blood vessels. The average number of the blood vessels per retinal zone was significantly higher in the group of patients with mild non-proliferative diabetic retinopathy than in the group with severe form in the optic disc and all five retinal zones. The average outer diameter of the evaluated retinal zones and optic disc vessels was significantly higher in the group with severe compared to the group with mild diabetic retinopathy.Morphological analysis of the retinal vessels on digital fundus photography and correlation with YKL-40 may be valuable for the follow-up of diabetic retinopathy.

  12. Detergent-enzymatic decellularization of swine blood vessels: insight on mechanical properties for vascular tissue engineering.

    Science.gov (United States)

    Pellegata, Alessandro F; Asnaghi, M Adelaide; Stefani, Ilaria; Maestroni, Anna; Maestroni, Silvia; Dominioni, Tommaso; Zonta, Sandro; Zerbini, Gianpaolo; Mantero, Sara

    2013-01-01

    Small caliber vessels substitutes still remain an unmet clinical need; few autologous substitutes are available, while synthetic grafts show insufficient patency in the long term. Decellularization is the complete removal of all cellular and nuclear matters from a tissue while leaving a preserved extracellular matrix representing a promising tool for the generation of acellular scaffolds for tissue engineering, already used for various tissues with positive outcomes. The aim of this work is to investigate the effect of a detergent-enzymatic decellularization protocol on swine arteries in terms of cell removal, extracellular matrix preservation, and mechanical properties. Furthermore, the effect of storage at -80°C on the mechanical properties of the tissue is evaluated. Swine arteries were harvested, frozen, and decellularized; histological analysis revealed complete cell removal and preserved extracellular matrix. Furthermore, the residual DNA content in decellularized tissues was far low compared to native one. Mechanical testings were performed on native, defrozen, and decellularized tissues; no statistically significant differences were reported for Young's modulus, ultimate stress, compliance, burst pressure, and suture retention strength, while ultimate strain and stress relaxation of decellularized vessels were significantly different from the native ones. Considering the overall results, the process was confirmed to be suitable for the generation of acellular scaffolds for vascular tissue engineering.

  13. Msx genes define a population of mural cell precursors required for head blood vessel maturation.

    Science.gov (United States)

    Lopes, Miguel; Goupille, Olivier; Saint Cloment, Cécile; Lallemand, Yvan; Cumano, Ana; Robert, Benoît

    2011-07-01

    Vessels are primarily formed from an inner endothelial layer that is secondarily covered by mural cells, namely vascular smooth muscle cells (VSMCs) in arteries and veins and pericytes in capillaries and veinules. We previously showed that, in the mouse embryo, Msx1(lacZ) and Msx2(lacZ) are expressed in mural cells and in a few endothelial cells. To unravel the role of Msx genes in vascular development, we have inactivated the two Msx genes specifically in mural cells by combining the Msx1(lacZ), Msx2(lox) and Sm22α-Cre alleles. Optical projection tomography demonstrated abnormal branching of the cephalic vessels in E11.5 mutant embryos. The carotid and vertebral arteries showed an increase in caliber that was related to reduced vascular smooth muscle coverage. Taking advantage of a newly constructed Msx1(CreERT2) allele, we demonstrated by lineage tracing that the primary defect lies in a population of VSMC precursors. The abnormal phenotype that ensues is a consequence of impaired BMP signaling in the VSMC precursors that leads to downregulation of the metalloprotease 2 (Mmp2) and Mmp9 genes, which are essential for cell migration and integration into the mural layer. Improper coverage by VSMCs secondarily leads to incomplete maturation of the endothelial layer. Our results demonstrate that both Msx1 and Msx2 are required for the recruitment of a population of neural crest-derived VSMCs.

  14. Intratumoral hemorrhage, vessel density, and the inflammatory reaction contribute to volume increase of sporadic vestibular schwannomas

    OpenAIRE

    de Vries, Maurits; Hogendoorn, Pancras C W; Briaire-de Bruyn, Inge; Malessy, Martijn J. A.; van der Mey, Andel G L

    2012-01-01

    Vestibular schwannomas show a large variation in growth rate, making prediction and anticipation of tumor growth difficult. More accurate prediction of clinical behavior requires better understanding of tumor biological factors influencing tumor progression. Biological processes like intratumoral hemorrhage, cell proliferation, microvessel density, and inflammation were analyzed in order to determine their role in vestibular schwannoma development. Tumor specimens of 67 patients surgically tr...

  15. Assessing blood vessel abnormality via extracting scattering coefficients from OCT images

    Science.gov (United States)

    Levitz, David; Andersen, Claus B.; Frosz, Michael H.; Thrane, Lars; Hansen, Peter R.; Jorgensen, Thomas M.; Andersen, Peter E.

    2003-10-01

    Background: Coronary artery disease (CAD) is the leading cause of mortality and morbidity in the industrialized world. Optical coherence tomography (OCT) is a high-resolution intravascular imaging technology with a potential for in vivo plaque characterization. Although structural remodeling of the arterial vessel wall during plaque development can change tissue optical scattering properties, very limited evidence is available on the exact optical scattering properties of plaques. The scattering coefficient, μs, and the anisotropy factor, g, can be derived from OCT images by fitting a theoretical model to individual depth-scans. The aim of the current study was to use this method to examine by OCT the scattering properties of human arteries with different stages of atherosclerotic lesion development. Methods: Normal (n=4), lipid-rich (n=4), and fibrous (n=3) aortic blocks as classified by parallel histopathologic examination were obtained within 24 hours of death and imaged by OCT. The intima was located in the OCT images, and then further split into 115 blocks (41 normal, 40 lipid-rich, and 34 fibrous) of adjacent OCT depth-scans transversely spanning ~200-300 μm. Scattering signals from each block were averaged and fit to the theoretical model. From these fittings, μs and g were extracted. Results and Discussion: The optical scattering properties of normal aortic intima were quite different from lipid-rich and fibrous lesions, respectively. We discovered that the normal intima was generally highly forward scattering, i.e., with 0.917diseased vessels were much less so. Furthermore, normal vessels usually had 15collagen, lipids, and elastin. Based on our findings, we defined a criteria of μs and g for normal intimas, using the above values of μs and g as cutoffs. Our "normal" criteria demonstrated high sensitivity (92.4%) and specificity (82.4%). We conclude, that a detailed analysis of the tissue optical scattering properties can enhance the capacity of OCT

  16. P/Q-type and T-type voltage-gated calcium channels are involved in the contraction of mammary and brain blood vessels from hypertensive patients

    DEFF Research Database (Denmark)

    Thuesen, A D; Lyngsø, K S; Rasmussen, L;

    2016-01-01

    AIM: Calcium channel blockers are widely used in cardiovascular diseases. Besides L-type channels, T- and P/Q-type calcium channels are involved in the contraction of human renal blood vessels. It was hypothesized that T- and P/Q-type channels are involved in the contraction of human brain...... and mammary blood vessels. METHODS: Internal mammary arteries from bypass surgery patients and cerebral arterioles from patients with brain tumours with and without hypertension were tested in a myograph and perfusion set-up. PCR and immunohistochemistry were performed on isolated blood vessels. RESULTS...... labelling of mammary and cerebral arteries revealed the presence of Cav 2.1 in endothelial and smooth muscle cells. Cav 3.1 was also detected in mammary arteries. CONCLUSION: P/Q- and T-type Cav are present in human internal mammary arteries and in cerebral penetrating arterioles. P/Q- and T-type calcium...

  17. Computer Simulations of Pulsatile Human Blood Flow Through 3D-Models of the Human Aortic Arch, Vessels of Simple Geometry and a Bifurcated Artery: Investigation of Blood Viscosity and Turbulent Effects

    CERN Document Server

    Sultanov, Renat A

    2008-01-01

    We report computational results of blood flow through a model of the human aortic arch and a vessel of actual diameter and length. On the top of the aortic arch the branching of the %%three arteries are included: the subclavian and jugular. A realistic pulsatile flow is used in all simulations. Calculations for bifurcation type vessels are also carried out and presented. Different mathematical methods for numerical solution of the fluid dynamics equations have been considered. The non-Newtonian behaviour of the human blood is investigated together with turbulence effects. A detailed time-dependent mathematical convergence test has been carried out. The results of computer simulations of the blood flow in vessels of three different geometries are presented: for pressure, strain rate and velocity component distributions we found significant disagreements between our results obtained with realistic non-Newtonian treatment of human blood and the widely used method in the literature: a simple Newtonian approximati...

  18. BLOOD VESSELS SEGMENTATION BY RADIAL GRADIENT SYMMETRY METHOD VIA DIFFERENT THRESHOLD VALUES

    Directory of Open Access Journals (Sweden)

    Kumar Parasuraman

    2015-02-01

    Full Text Available A Key identifier for some diseases such as arteriosclerosis, hypertension, macular edema, diabetes mellitus, and the recognition qualities of geometrical changes in retinal veins and supply routes are recognized by Retinal Vein morphology and might be connected to a mixed carrier of clinical studies. Extraction of the retinal veins is a help to see all the more about its morphology and will give a superior wellspring of data for contemplating the different related diseases. Two of the significant issues in the extraction of retinal veins are the vicinity of a wide assortment of vessel widths and inhomogeneous foundation of the retina. Machine based dissection for computerized extraction of veins in retinal images will help eye mind pro's screen bigger populaces for vessel variations from the norm. In this extend a technique for robotized extraction of fundus pictures of the retinal vein is introduced. This paper displays another strategy for vein recognition in computerized retinal pictures. In this system first separating is carried out utilizing reciprocal channel to uproot the commotions in the picture and second, differentiates the fundus picture into red, green and blue channels. Third, Kirsch's format with spatial separating is utilized to discover the beginning and bearing of the veins and for smoothing the limits. Fourth, the veins are fragmented by applying threshold values and by utilizing outspread radial symmetry strategy. These segmentations are looked at against manual estimations and between imaging strategies. Its adequacy and strength with distinctive picture conditions, together with its smoothness and quick usage, make this vein division proposal suitable for retinal picture workstation examination, for example, computerized screening for right on time diabetic retinopathy discovery.

  19. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization

    Science.gov (United States)

    Huber, Birgit; Engelhardt, Sascha; Meyer, Wolfdietrich; Krüger, Hartmut; Wenz, Annika; Schönhaar, Veronika; Tovar, Günter E. M.; Kluger, Petra J.; Borchers, Kirsten

    2016-01-01

    Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM), biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap® technology by the authors. PMID:27104576

  20. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization

    Directory of Open Access Journals (Sweden)

    Birgit Huber

    2016-04-01

    Full Text Available Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM, biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap® technology by the authors.

  1. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization.

    Science.gov (United States)

    Huber, Birgit; Engelhardt, Sascha; Meyer, Wolfdietrich; Krüger, Hartmut; Wenz, Annika; Schönhaar, Veronika; Tovar, Günter E M; Kluger, Petra J; Borchers, Kirsten

    2016-01-01

    Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM), biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap(®) technology by the authors. PMID:27104576

  2. Time-dependent effects of castration on the bladder function and histological changes in the bladder and blood vessels.

    Science.gov (United States)

    Magari, Tomohiro; Shibata, Yasuhiro; Arai, Seiji; Kashiwagi, Bunzo; Suzuki, Keiji; Suzuki, Kazuhiro

    2014-01-01

    We examined the effect of androgens on bladder blood flow (BBF), bladder function and histological changes in castrated male rats. Male Wistar rats were classified into unoperated group (control group), groups castrated at the age of 8 weeks (group 8wPC) and groups castrated at the age of 4 weeks (group 4wPC). Each rat was used at the age of 20 weeks. BBF was measured using fluorescent microspheres. Bladder cystometry was performed without anesthesia or restraint; the bladder was first irrigated with saline and then with 0.25% acetic acid (AA) solution. Maximum voiding pressure and voiding interval were measured. The bladder and iliac artery were histologically examined for differences in smooth muscle and quantity of collagen fiber to analyze the effect of castration on the smooth muscle content. No differences were noted in BBF following castration. The voiding intervals for all groups were shortened (P control group (Pcontrol group (Pblood vessels.

  3. Reflection-mode photoacoustic microscopy using a hollow focused ultrasound transducer for in vivo imaging of blood vessels

    Institute of Scientific and Technical Information of China (English)

    Yuan Yi; Yang Si-Hua

    2012-01-01

    A reflection-mode photoacoustic microscope using a hollow focused ultrasound transducer is developed for highresolution in vivo imaging.A confocal structure of the laser and the ultrasound is used to improve the system resolution.The axial and lateral resolutions of the system are measured to be~32 μm and~58 μm,respectively.Ex vivo and in vivo modes are tested to validate the imaging capability of the photoacoustic microscope.The adjacent vein and artery can be seen clearly from the reconstructed photoacoustic images.The results demonstrate that the reflectionmode photoacoustic microscope can be used for high-resolution imaging of micro-blood vessels,which would be of great benefit for monitoring the neovascularization in tumor angiogenesis.

  4. Careful treatment planning enables safe ablation of liver tumors adjacent to major blood vessels by percutaneous irreversible electroporation (IRE)

    International Nuclear Information System (INIS)

    Irreversible electroporation (IRE) is a tissue ablation method, which relies on the phenomenon of electroporation. When cells are exposed to a sufficiently electric field, the plasma membrane is disrupted and cells undergo an apoptotic or necrotic cell death. Although heating effects are known IRE is considered as non-thermal ablation technique and is currently applied to treat tumors in locations where thermal ablation techniques are contraindicated. The manufacturer of the only commercially available pulse generator for IRE recommends a voltage-to-distance ratio of 1500 to 1700 V/cm for treating tumors in the liver. However, major blood vessels can influence the electric field distribution. We present a method for treatment planning of IRE which takes the influence of blood vessels on the electric field into account; this is illustrated on a treatment of 48-year-old patient with a metastasis near the remaining hepatic vein after a right side hemi-hepatectomy. Output of the numerical treatment planning method shows that a 19.9 cm3 irreversible electroporation lesion was generated and the whole tumor was covered with at least 900 V/cm. This compares well with the volume of the hypodense lesion seen in contrast enhanced CT images taken after the IRE treatment. A significant temperature raise occurs near the electrodes. However, the hepatic vein remains open after the treatment without evidence of tumor recurrence after 6 months. Treatment planning using accurate computer models was recognized as important for electrochemotherapy and irreversible electroporation. An important finding of this study was, that the surface of the electrodes heat up significantly. Therefore the clinical user should generally avoid placing the electrodes less than 4 mm away from risk structures when following recommendations of the manufacturer

  5. The structural and functional effects of fine particulate matter from cooking oil fumes on rat umbilical cord blood vessels.

    Science.gov (United States)

    Zhu, Xiaoxia; Hou, Lijuan; Zhang, Jian; Yao, Cijiang; Liu, Ying; Zhang, Chao; Xu, Yachun; Cao, Jiyu

    2016-08-01

    A growing body of epidemiological evidence has supported the association between maternal exposure to airborne fine particulate matter (PM2.5) during pregnancy and adverse pregnancy outcomes. However, the specific biological mechanisms implicated in the causes of adverse pregnancy outcomes are not well defined. In this study, a pregnant rat model of exposure to different doses of cooking oil fumes (COFs)-derived PM2.5 by tail intravenous injection in different pregnant stages was established. The results indicated that exposure to COFs-derived PM2.5 was associated with adverse pregnancy outcomes, changed the structure of umbilical cord blood vessels, decreased the diameter and lumen area, and increased wall thickness. What's more, a significant increase of maximum contraction tension was observed in the early pregnancy high-dose exposure group and pregnant low-dose exposure group compared to the control group. Based on the maximum contraction tension, acetylcholine (ACh) did not induce vasodilation but caused a dose-dependent constriction, and there were significant differences in the two groups compared to the control group. Exposure to COFs-derived PM2.5 impaired the vasomotor function of umbilical veins by affecting the expression of NO and ET-1. This is the first study that evaluated the association of risk of adverse pregnancy outcomes and pregnant rats exposed to COFs-derived PM2.5 and primarily explored the potential mechanisms of umbilical cord blood vessels injury on a rat model. More detailed vitro and vivo studies are needed to further explore the mechanism in the future.

  6. Vessel Segmentation and Blood Flow Simulation Using Level-Sets and Embedded Boundary Methods

    Energy Technology Data Exchange (ETDEWEB)

    Deschamps, T; Schwartz, P; Trebotich, D; Colella, P; Saloner, D; Malladi, R

    2004-12-09

    In this article we address the problem of blood flow simulation in realistic vascular objects. The anatomical surfaces are extracted by means of Level-Sets methods that accurately model the complex and varying surfaces of pathological objects such as aneurysms and stenoses. The surfaces obtained are defined at the sub-pixel level where they intersect the Cartesian grid of the image domain. It is therefore straightforward to construct embedded boundary representations of these objects on the same grid, for which recent work has enabled discretization of the Navier-Stokes equations for incompressible fluids. While most classical techniques require construction of a structured mesh that approximates the surface in order to extrapolate a 3D finite-element gridding of the whole volume, our method directly simulates the blood-flow inside the extracted surface without losing any complicated details and without building additional grids.

  7. MAPK and pro-inflammatory mediators in the walls of brain blood vessels following cerebral ischemia

    OpenAIRE

    Maddahi, Aida

    2012-01-01

    INTRODUCTION Stroke is a serious neurological disease which may lead to death and severe disability [1, 2]. There are two major types of stroke: ischemic and hemorrhagic stroke. Both are associated with disruption of blood flow to a part of the brain with rapid depletion of cellular energy and oxygen, resulting in ionic disturbances and eventually neuronal cell death [3]. The pathologic process that develops after stroke is divided into acute (within hours), sub-acute (hours to days), ...

  8. Prediction of melanoma metastasis by the Shields index based on lymphatic vessel density

    Directory of Open Access Journals (Sweden)

    Metcalfe Chris

    2010-05-01

    Full Text Available Abstract Background Melanoma usually presents as an initial skin lesion without evidence of metastasis. A significant proportion of patients develop subsequent local, regional or distant metastasis, sometimes many years after the initial lesion was removed. The current most effective staging method to identify early regional metastasis is sentinel lymph node biopsy (SLNB, which is invasive, not without morbidity and, while improving staging, may not improve overall survival. Lymphatic density, Breslow's thickness and the presence or absence of lymphatic invasion combined has been proposed to be a prognostic index of metastasis, by Shields et al in a patient group. Methods Here we undertook a retrospective analysis of 102 malignant melanomas from patients with more than five years follow-up to evaluate the Shields' index and compare with existing indicators. Results The Shields' index accurately predicted outcome in 90% of patients with metastases and 84% without metastases. For these, the Shields index was more predictive than thickness or lymphatic density. Alternate lymphatic measurement (hot spot analysis was also effective when combined into the Shields index in a cohort of 24 patients. Conclusions These results show the Shields index, a non-invasive analysis based on immunohistochemistry of lymphatics surrounding primary lesions that can accurately predict outcome, is a simple, useful prognostic tool in malignant melanoma.

  9. Surgical manipulation of major blood vessels invaded by retroperitoneal tumors%腹膜后肿瘤累及腹部大血管的处理

    Institute of Scientific and Technical Information of China (English)

    田文

    2009-01-01

    腹膜后肿瘤出现症状就诊时,肿瘤通常发展的比较大且多已累及重要血管.腹膜后肿瘤所累及重要血管外科处理的关键是提高肿瘤切除率.首先应用CT、MRI及数字减影血管造影等影像学方法 判断腹膜后肿瘤所累及重要血管的情况.良好显露为控制和处理血管出血创造了必要条件,增加了手术安全性.血管阻断前应行局部或全身肝素化,有些重要的血管需行修复和重建.自体血管的使用已日渐成熟,人工血管和补片的使用为手术提供了便利.重建时要注意恢复血管功能及防止血管损伤和术后血栓形成.%When the retroperitoneal tumor patients with clinic symptoms seek medical treatment, the tumors are usually large and involve major blood vessels. The correct surgical manipulation of major blood vessels invaded by retroperitoneal tumors is important to raise the resection rate. The examination of CT, MRI and DSA (digital subtration angiography) can help preoperative evaluation and preparation for major blood vessels resection and reconstruction. Good vessel exposing plays a necessary part in vessel resection and reconstruction. Before controling bleeding and vessel reconstruction, local or systemic heparinization should be necessary. Some important vessels need to repair and reconstruction. Now using autologous blood vessels for vessel reconstruction has been more common, artificial blood vessels and mesh greatly facilitate reconstruction. It should be paid attention to vascular function reconstruction, preventing postoperative vascular injury and thrombosis.

  10. Processing of MRI images weighted in TOF for blood vessels analysis: 3-D reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez D, J.; Cordova F, T. [Universidad de Guanajuato, Campus Leon, Departamento de Ingenieria Fisica, Loma del Bosque No. 103, Lomas del Campestre, 37150 Leon, Guanajuato (Mexico); Cruz A, I., E-mail: hernandezdj.gto@gmail.com [CONACYT, Centro de Investigacion en Matematicas, A. C., Jalisco s/n, Col. Valenciana, 36000 Guanajuato, Gto. (Mexico)

    2015-10-15

    This paper presents a novel presents an approach based on differences of intensities for the identification of vascular structures in medical images from MRI studies of type time of flight method (TOF). The plating method hypothesis gave high intensities belonging to the vascular system image type TOF can be segmented by thresholding of the histogram. The enhanced vascular structures is performed using the filter Vesselness, upon completion of a decision based on fuzzy thresholding minimizes error in the selection of vascular structures. It will give a brief introduction to the vascular system problems and how the images have helped diagnosis, is summarized the physical history of the different imaging modalities and the evolution of digital images with computers. Segmentation and 3-D reconstruction became image type time of flight; these images are typically used in medical diagnosis of cerebrovascular diseases. The proposed method has less error in segmentation and reconstruction of volumes related to the vascular system, clear images and less noise compared with edge detection methods. (Author)

  11. Computer-assisted spatial reconstruction of cerebral blood vessels and intracranial aneurysms

    Directory of Open Access Journals (Sweden)

    Nikolić Igor M.

    2006-01-01

    Full Text Available Introduction. Today, many medical procedures are based on image analysis with the aim of providing accurate diagnosis and optimal treatment. The goal of this report was to present clinical implications of computer-assisted geometric design of carotid aneurysms. Material and methods. In this study, the three-dimensional reconstruction was based on the approximation power of the parametric spline function, which achieves interpolation and surface fitting of the arterial information obtained by conventional angiography. Two views of conventional angiograms (anterioposterior and lateral views were used with a personal computer and commercial software. Results. This method of three-dimensional generated images was applied in 45 cases of cerebral aneurysms in carotid bifurcation. 3D reconstructions were made in approximately 20 minutes. They contributed to assessing vascular structures, and it was possible to rotate the three-dimensional image in different angles. Conclusion. Three-dimensional reconstruction of cerebral vessels is very useful for discussing surgical strategies preoperatively. Furthermore, it could also be used in endovascular procedures. .

  12. Microwave Ablation Using Four-Tine Antenna: Effects of Blood Flow Velocity, Vessel Location, and Total Displacement on Porous Hepatic Cancer Tissue

    Science.gov (United States)

    Chaichanyut, Montree

    2016-01-01

    This research is concerned with microwave ablation analyses using a 2.45 GHz four-tine (4T) antenna for hepatic cancer tissue. In the study, three-dimensional finite-element models were utilized to examine the tissue temperature distributions during and after MW ablation. A preliminary study was first carried out with regard to the specific absorption rates along the 4T antenna insertion depths and the temperature distributions inside the solid and porous liver models with either 3 cm-in-diameter tumor or 5 cm-in-diameter tumor. Based on the preliminary results, the porous models were further examined for the effect of varying blood flow velocities (0–200 cm/s) with a 1 cm-in-diameter blood vessel next to the antenna and also for the effect of vessel-antenna locations (0, 0.8, and 1.3 cm) with a constant blood flow velocity of 16.7 cm/s. All scenarios were simulated under temperature-controlled mode (90°C). The findings revealed that the blood flow velocity and vessel location influence the ablation effectiveness and that increased blood flow inhibits heat transfer to the vessel wall. At the nearest and farthest vessel-antenna locations (0 and 1.3 cm), approximately 90.3% and 99.55% of the cancer cells were eradicated except for the areas adjacent to the vessel. In addition, total tissue thermal displacement is 5.9 mm which is 6.59% of the total length of the overall model. PMID:27642364

  13. Microwave Ablation Using Four-Tine Antenna: Effects of Blood Flow Velocity, Vessel Location, and Total Displacement on Porous Hepatic Cancer Tissue.

    Science.gov (United States)

    Chaichanyut, Montree; Tungjitkusolmun, Supan

    2016-01-01

    This research is concerned with microwave ablation analyses using a 2.45 GHz four-tine (4T) antenna for hepatic cancer tissue. In the study, three-dimensional finite-element models were utilized to examine the tissue temperature distributions during and after MW ablation. A preliminary study was first carried out with regard to the specific absorption rates along the 4T antenna insertion depths and the temperature distributions inside the solid and porous liver models with either 3 cm-in-diameter tumor or 5 cm-in-diameter tumor. Based on the preliminary results, the porous models were further examined for the effect of varying blood flow velocities (0-200 cm/s) with a 1 cm-in-diameter blood vessel next to the antenna and also for the effect of vessel-antenna locations (0, 0.8, and 1.3 cm) with a constant blood flow velocity of 16.7 cm/s. All scenarios were simulated under temperature-controlled mode (90°C). The findings revealed that the blood flow velocity and vessel location influence the ablation effectiveness and that increased blood flow inhibits heat transfer to the vessel wall. At the nearest and farthest vessel-antenna locations (0 and 1.3 cm), approximately 90.3% and 99.55% of the cancer cells were eradicated except for the areas adjacent to the vessel. In addition, total tissue thermal displacement is 5.9 mm which is 6.59% of the total length of the overall model. PMID:27642364

  14. Arginase reciprocally regulates nitric oxide synthase activity and contributes to endothelial dysfunction in aging blood vessels

    Science.gov (United States)

    Berkowitz, Dan E.; White, Ron; Li, Dechun; Minhas, Khalid M.; Cernetich, Amy; Kim, Soonyul; Burke, Sean; Shoukas, Artin A.; Nyhan, Daniel; Champion, Hunter C.; Hare, Joshua M.

    2003-01-01

    BACKGROUND: Although abnormal L-arginine NO signaling contributes to endothelial dysfunction in the aging cardiovascular system, the biochemical mechanisms remain controversial. L-arginine, the NO synthase (NOS) precursor, is also a substrate for arginase. We tested the hypotheses that arginase reciprocally regulates NOS by modulating L-arginine bioavailability and that arginase is upregulated in aging vasculature, contributing to depressed endothelial function. METHODS AND RESULTS: Inhibition of arginase with (S)-(2-boronoethyl)-L-cysteine, HCl (BEC) produced vasodilation in aortic rings from young (Y) adult rats (maximum effect, 46.4+/-9.4% at 10(-5) mol/L, P<0.01). Similar vasorelaxation was elicited with the additional arginase inhibitors N-hydroxy-nor-L-arginine (nor-NOHA) and difluoromethylornithine (DFMO). This effect required intact endothelium and was prevented by 1H-oxadiazole quinoxalin-1-one (P<0.05 and P<0.001, respectively), a soluble guanylyl cyclase inhibitor. DFMO-elicited vasodilation was greater in old (O) compared with Y rat aortic rings (60+/-6% versus 39+/-6%, P<0.05). In addition, BEC restored depressed L-arginine (10(-4) mol/L)-dependent vasorelaxant responses in O rings to those of Y. Arginase activity and expression were increased in O rings, whereas NOS activity and cyclic GMP levels were decreased. BEC and DFMO suppressed arginase activity and restored NOS activity and cyclic GMP levels in O vessels to those of Y. CONCLUSIONS: These findings demonstrate that arginase modulates NOS activity, likely by regulating intracellular L-arginine availability. Arginase upregulation contributes to endothelial dysfunction of aging and may therefore be a therapeutic target.

  15. Hard X-ray in-line outline imaging for blood vessels: first generation synchrotron radiation without contrast agents in vitro

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: Phase-contrast X-ray imaging which reduces radiation exposure, is a promising technique for observing the inner structures of biological soft tissues without the aid of contrast agents.The present study intends to depict blood vessels of rabbits and human livers with hard X-ray in-line out line imaging without contrast agents using synchrotron radiation. Methods: All samples were fixed with formalin and sliced into 6 mm sections. The imaging experiments were performed with Fuji-IX80 films on the 4W1A light beam of the first generation synchrotron radiation in Beijing, China. The device of the ex periment, which supplies a maximum light spot size of 20× 10 mm was similar to that of in-line holography. The photon energy was set at 8 KeV and high quality imagines were obtained by altering the distance between the sample and the film. Results: The trees of rabbit-liver blood vessels and the curved vessels of the cirrhotic human liver were revealed on the images, where vessels < 20 μm in diameter were differentiated. Conclusion: These results show that the blood vessels of liver samples can be revealed by using hard X-ray in-line outline imaging with the first generation synchrotron radiation without contrast agents.

  16. Three-dimensional Gd-DTPA MR angiography of cerebral blood vessels

    International Nuclear Information System (INIS)

    Subtraction angiography based on three-dimensional fast MR imaging techniques using rephasing and dephasing gradient pulses is widely used. Similar angiograms can be obtained with three-dimensional gradient techniques before and after the administration of Gd-DTPA followed by imaging subtraction. As Gd-DTPA does not penetrate the blood-brain barrier, it does not alter brain images. Measurements were carried out in 14 patients with a 1.0-T whole-body imager (Siemens, Magnetom). Gd-DTPA angiography was superior to rephased-dephased angiography because of the higher signal intensity, lower noise due to short echo times, and high contrast for moving spins caused by Gd-DTPA

  17. Functional photoacoustic micro-imaging of cerebral hemodynamic changes in single blood vessels after photo-induced brain stroke

    Science.gov (United States)

    Liao, Lun-De; Chen, You-Yin; Lin, Chin-Teng; Li, Meng-Lin

    2013-03-01

    Studying the functional hemodynamic roles of individual cerebral cortical arterioles in maintaining both the structure and function of cortical regions during and after brain stroke in small animals is an important issue. Recently, functional photoacoustic microscopy (fPAM) has been proved as a reliable imaging technique to probe the total hemoglobin concentration (HbT), cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) in single cerebral blood vessels of rats. Here, we report the application of fPAM associated with electrophysiology recordings to investigating functional hemodynamic changes in single cortical arterioles of rats with electrical forepaw stimulation after photo-induced ischemic stroke. Because of the weak optical focusing nature of our fPAM system, photo-induced ischemic stroke targeting single cortical arterioles can be easily conducted with simple adaptation. Functional HbT, CBV and SO2 changes associated with the induced stroke in selected arterioles from the anterior cerebral artery system were imaged with 36 x 65-μm spatial resolution. Experimental results showed that after photo-occlusion of a single arteriole, the functional changes of nearby arterioles in cerebral cortex only can be observed immediately after the stroke. After a few minutes of stroke onset, there are no significant functional changes under the forepaw stimulation, suggesting that alternate blood flow routes are not actively recruited. The fPAM with electrophysiology recordings complements existing imaging techniques and has the potential to offer a favorable tool for explicitly studying cerebral hemodynamics in small animal models of photo-indcued ischemic stroke.

  18. Real-time intraoperative full-range complex FD-OCT guided cerebral blood vessel identification and brain tumor resection in neurosurgery

    Science.gov (United States)

    Zhang, Kang; Huang, Yong; Pradilla, Gustavo; Tyler, Betty; Kang, Jin U.

    2011-03-01

    This work utilized an ultra-high-speed full-range complex-conjugate-free optical coherence tomography (FD-OCT) system to perform real-time intraoperative imaging to guide two common neurosurgical procedures: the cerebral blood vessel identification and the brain tumor resection. The cerebral blood vessel identification experiment is conducted ex vivo on human cadaver specimen. Specific cerebral arteries and veins in different positions of the specimen are visualized and the spatial relations between adjacent vessels are indentified through real-time 3D visualization. The brain tumor resection experiment is conducted in vivo on 9L gliomas established in rat brains. The normal brain-tumor margin can be clearly identified in depth of the tissue from sagittal, coronal and axial slices of the intraoperatively acquired 3D data set. The real-time full-range FD-OCT guided in vivo rat flank tumor resection is also conducted.

  19. N-epsilon-(carboxymethyl)lysine depositions in intramyocardial blood vessels in human and rat acute myocardial infarction - A predictor or reflection of infarction?

    NARCIS (Netherlands)

    A. Baidoshvili; P.A.J. Krijnen; K. Kupreishvili; C. Ciurana; W. Bleeker; R. Nijmeijer; C.A. Visser; F.C. Visser; C.J.L.M. Meijer; W. Stooker; L. Eijsman; V.W.M. van Hinsbergh; C.E. Hack; H.W.M. Niessen; C.G. Schalkwijk

    2006-01-01

    Objective - Advanced glycation end products ( AGEs), such as N-epsilon-( carboxymethyl) lysine ( CML), are implicated in vascular disease. We previously reported increased CML accumulation in small intramyocardial blood vessels in diabetes patients. Diabetes patients have an increased risk for acute

  20. Remote non-invasive stereoscopic imaging of blood vessels: first in-vivo results of a new multispectral contrast enhancement technology

    NARCIS (Netherlands)

    Wieringa, F.P.; Mastik, F.; Cate, F.J. ten; Neumann, H.A.M.; Steen, A.F.W. van der

    2006-01-01

    We describe a contactless optical technique selectively enhancing superficial blood vessels below variously pigmented intact human skin by combining images in different spectral bands. Two CMOS-cameras, with apochromatic lenses and dual-band LED-arrays, simultaneously streamed Left (L) and Right (R)

  1. Detection and quantification of subtle changes in red blood cell density using a cell phone.

    Science.gov (United States)

    Felton, Edward J; Velasquez, Anthony; Lu, Shulin; Murphy, Ryann O; ElKhal, Abdala; Mazor, Ofer; Gorelik, Pavel; Sharda, Anish; Ghiran, Ionita C

    2016-08-16

    Magnetic levitation has emerged as a technique that offers the ability to differentiate between cells with different densities. We have developed a magnetic levitation system for this purpose that distinguishes not only different cell types but also density differences in cells of the same type. This small-scale system suspends cells in a paramagnetic medium in a capillary placed between two rare earth magnets, and cells levitate to an equilibrium position determined solely by their density. Uniform reference beads of known density are used in conjunction with the cells as a means to quantify their levitation positions. In one implementation images of the levitating cells are acquired with a microscope, but here we also introduce a cell phone-based device that integrates the magnets, capillary, and a lens into a compact and portable unit that acquires images with the phone's camera. To demonstrate the effectiveness of magnetic levitation in cell density analysis we carried out levitation experiments using red blood cells with artificially altered densities, and also levitated those from donors. We observed that we can distinguish red blood cells of an anemic donor from those that are healthy. Since a plethora of disease states are characterized by changes in cell density magnetic cell levitation promises to be an effective tool in identifying and analyzing pathologic states. Furthermore, the low cost, portability, and ease of use of the cell phone-based system may potentially lead to its deployment in low-resource environments. PMID:27431921

  2. 改良小口径人工血管的血液相容性研究*%The Study of the Modified Small-caliber Artificial Blood Vessel

    Institute of Scientific and Technical Information of China (English)

    李辉; 陈群清; 李少彬; 闫玉生

    2013-01-01

    Objective:To research the hemocompatibility of the modified small-caliber artificial blood vessel(the combined blood vessel). Method:To produce a combined blood vessel with a small-caliber expanded polytetrafluoroethylene vessel coated by silk fibroin film,which sulfonated by low temperature plasma treatment,to evaluated the hemocompatibility and safety of the combined blood vessel including dynamic cruor time test, recalcification time,and the hemolysis test.Result:Hemolytic test indicated that the vascular hemolysis was 4.5%,in line with the requirements of materials hemolytic.The average value of absorbance-clotting time of the combined blood vessel was higher than that of the control blood vessel,and declined more slowly.The recalcification time of the combined blood vessel was significantly longer than that of control blood vessel(610.06±37.65 vs 450.00±32.18 seconds,P<0.01).Conclusion:Form this experiment,we demonstrate the combined blood vessel has a good hemocompatibility.%  目的:研究改良小口径人工血管的血液相容性。方法:将丝素蛋白膜涂覆于聚四氟乙烯小口径人工血管内侧壁,采用等离子体技术对涂覆后的小口径人工血管磺酸化,制成改良小口径人工血管;改良小口径人工血管的溶血相关安全性以体外溶血实验检测,同时行动态凝血、复钙实验评价复合血管血液相容性。结果:溶血试验提示复合血管的溶血率为4.5%,符合材料溶血要求;动态凝血中根据各时间点吸光度平均值可见复合血管组吸光度整体位于普通血管之上,且下降趋势较缓,经历时间较长,与普通血管相比,其抗凝血性能较好;复钙实验中复合血管组平均时间为(450.00±32.18)s,小于对照组平均时间(610.06±37.65)s,两样本t检验提示P=0.000,提示两者差异有统计学意义。结论:改良小口径人工血管具有良好的血液相容性。

  3. Evaluation of sildenafil pressurized metered dose inhalers as a vasodilator in umbilical blood vessels of chicken egg embryos.

    Science.gov (United States)

    Sawatdee, Somchai; Hiranphan, Phetai; Laphanayos, Kampanart; Srichana, Teerapol

    2014-01-01

    Sildenafil citrate is a selective phosphodiesterase-5 inhibitor used for the treatment for erectile dysfunction and pulmonary hypertension. The delivery of sildenafil directly to the lung could have several advantages over conventional treatments for pulmonary hypertension because of the local delivery, a more rapid onset of response, and reduced side effects. The major problem of sildenafil citrate is its limited solubility in water. Sildenafil citrate was complexed with cyclodextrins (CDs) to enhance its water solubility prior to development as an inhaled preparation. Four sildenafil citrate inhaled formulations were prepared with the aid of HP-β-CD (#1), α-CD (#2) and γ-CD (#3) and their effects were compared with the formulations without CDs (#4). The sildenafil citrate pressurized metered dose inhalers (pMDI) used ethanol as a solvent, PEG400 as a stabilizing agent, sorbitan monooleate as a surfactant and HFA-134a as a propellant. All formulations consisted of sildenafil citrate equivalent to a sildenafil content of 20μg/puff. These products were evaluated according to a standard guideline of inhalation products. Vasodilation testing was performed to investigate the efficacy of sildenafil pMDIs in relieving a vasoconstricted umbilical blood vessel of the chicken egg embryo. The sildenafil contents of the pMDI formulations #1-#3 were within the acceptance criteria (80-120%). The emitted doses (ED) were 102.3±11.5%, the fine particle fractions (FPF) were 60.5±5.6% and the mass median aerodynamic diameters (MMAD) were 2.3±0.3μm. The vasodilatory activity of those formulations reduced umbilical blood pressure by 67.1-73.7% after treatment by intravenous injection whereas only a 50.1-58.0% reduced blood pressure was obtained after direct spraying of the sildenafil pMDI containing CDs. With sildenafil formulations of a pMDI without CD the blood pressure was reduced by only 39.0% (P-valuevessels of chicken egg embryos after spraying sildenafil-CDs pMDIs was

  4. Time-dependent effects of castration on the bladder function and histological changes in the bladder and blood vessels

    Institute of Scientific and Technical Information of China (English)

    Tomohiro Magari; Yasuhiro Shibata; Seiji Arai; Bunzo Kashiwagi; Keiji Suzuki; Kazuhiro Suzuki

    2014-01-01

    We examined the effect of androgens on bladder blood lfow (BBF), bladder function and histological changes in castrated male rats. Male Wistar rats were classiifed into unoperated group (control group), groups castrated at the age of 8 weeks (group 8wPC) and groups castrated at the age of 4 weeks (group 4wPC). Each rat was used at the age of 20 weeks. BBF was measured using lfuorescent microspheres. Bladder cystometry was performed without anesthesia or restraint;the bladder was ifrst irrigated with saline and then with 0.25%acetic acid (AA) solution. Maximum voiding pressure and voiding interval were measured. The bladder and iliac artery were histologically examined for differences in smooth muscle and quantity of collagen ifber to analyze the effect of castration on the smooth muscle content. No differences were noted in BBF following castration. The voiding intervals for all groups were shortened (P<0.001) following AA irrigation. No signiifcant difference was noted in the maximum voiding pressure. Histological changes were observed in bladder and iliac artery. Smooth muscle/collagen ratio at the bladder was lower in groups 8wPC and 4wPC compared to the control group (P<0.01), while that at the iliac artery was decreased in group 4wPC compared to the control group (P<0.001). In conclusion, our ifndings indicate that castration does not alter BBF, but leads to histological changes in the bladder as well as its associated blood vessels.

  5. Time-dependent effects of castration on the bladder function and histological changes in the bladder and blood vessels

    Directory of Open Access Journals (Sweden)

    Tomohiro Magari

    2014-06-01

    Full Text Available We examined the effect of androgens on bladder blood flow (BBF, bladder function and histological changes in castrated male rats. Male Wistar rats were classified into unoperated group (control group, groups castrated at the age of 8 weeks (group 8wPC and groups castrated at the age of 4 weeks (group 4wPC. Each rat was used at the age of 20 weeks. BBF was measured using fluorescent microspheres. Bladder cystometry was performed without anesthesia or restraint; the bladder was first irrigated with saline and then with 0.25% acetic acid (AA solution. Maximum voiding pressure and voiding interval were measured. The bladder and iliac artery were histologically examined for differences in smooth muscle and quantity of collagen fiber to analyze the effect of castration on the smooth muscle content. No differences were noted in BBF following castration. The voiding intervals for all groups were shortened (P < 0.001 following AA irrigation. No significant difference was noted in the maximum voiding pressure. Histological changes were observed in bladder and iliac artery. Smooth muscle/collagen ratio at the bladder was lower in groups 8wPC and 4wPC compared to the control group (P< 0.01, while that at the iliac artery was decreased in group 4wPC compared to the control group (P< 0.001. In conclusion, our findings indicate that castration does not alter BBF, but leads to histological changes in the bladder as well as its associated blood vessels.

  6. Adaptive increases in expression and vasodilator activity of estrogen receptor subtypes in a blood vessel-specific pattern during pregnancy.

    Science.gov (United States)

    Mata, Karina M; Li, Wei; Reslan, Ossama M; Siddiqui, Waleed T; Opsasnick, Lauren A; Khalil, Raouf A

    2015-11-15

    Normal pregnancy is associated with adaptive hemodynamic, hormonal, and vascular changes, and estrogen (E2) may promote vasodilation during pregnancy; however, the specific E2 receptor (ER) subtype, post-ER signaling mechanism, and vascular bed involved are unclear. We tested whether pregnancy-associated vascular adaptations involve changes in the expression/distribution/activity of distinct ER subtypes in a blood vessel-specific manner. Blood pressure (BP) and plasma E2 were measured in virgin and pregnant (day 19) rats, and the thoracic aorta, carotid artery, mesenteric artery, and renal artery were isolated for measurements of ERα, ERβ, and G protein-coupled receptor 30 [G protein-coupled ER (GPER)] expression and tissue distribution in parallel with relaxation responses to E2 (all ERs) and the specific ER agonist 4,4',4″-(4-propyl-[1H]-pyrazole-1,3,5-triyl)-tris-phenol (PPT; ERα), diarylpropionitrile (DPN; ERβ), and G1 (GPER). BP was slightly lower and plasma E2 was higher in pregnant versus virgin rats. Western blots revealed increased ERα and ERβ in the aorta and mesenteric artery and GPER in the aorta of pregnant versus virgin rats. Immunohistochemistry revealed that the increases in ERs were mainly in the intima and media. In phenylephrine-precontracted vessels, E2 and PPT caused relaxation that was greater in the aorta and mesenteric artery but similar in the carotid and renal artery of pregnant versus virgin rats. DPN- and G1-induced relaxation was greater in the mesenteric and renal artery than in the aorta and carotid artery, and aortic relaxation to G1 was greater in pregnant versus virgin rats. The nitric oxide synthase inhibitor N(ω)-nitro-l-arginine methyl ester with or without the cyclooxygenase inhibitor indomethacin with or without the EDHF blocker tetraethylammonium or endothelium removal reduced E2, PPT, and G1-induced relaxation in the aorta of pregnant rats, suggesting an endothelium-dependent mechanism, but did not affect E2-, PPT

  7. Smooth Muscle Cell Alignment and Phenotype Control by Melt Spun Polycaprolactone Fibers for Seeding of Tissue Engineered Blood Vessels

    Directory of Open Access Journals (Sweden)

    Animesh Agrawal

    2015-01-01

    Full Text Available A method has been developed to induce and retain a contractile phenotype for vascular smooth muscle cells, as the first step towards the development of a biomimetic blood vessel construct with minimal compliance mismatch. Melt spun PCL fibers were deposited on a mandrel to form aligned fibers of 10 μm in diameter. The fibers were bonded into aligned arrangement through dip coating in chitosan solution. This formed a surface of parallel grooves, 10 μm deep by 10 μm across, presenting a surface layer of chitosan to promote cell surface interactions. The aligned fiber surface was used to culture cells present in the vascular wall, in particular fibroblasts and smooth muscle cells. This topography induced “surface guidance” over the orientation of the cells, which adopted an elongated spindle-like morphology, whereas cells on the unpatterned control surface did not show such orientation, assuming more rhomboid shapes. The preservation of VSMC contractile phenotype on the aligned scaffold was demonstrated by the retention of α-SMA expression after several days of culture. The effect was assessed on a prototype vascular graft prosthesis fabricated from polylactide caprolactone; VSMCs aligned longitudinally along a fiberless tube, whereas, for the aligned fiber coated tubes, the VSMCs aligned in the required circumferential orientation.

  8. Smooth Muscle Cell Alignment and Phenotype Control by Melt Spun Polycaprolactone Fibers for Seeding of Tissue Engineered Blood Vessels.

    Science.gov (United States)

    Agrawal, Animesh; Lee, Bae Hoon; Irvine, Scott A; An, Jia; Bhuthalingam, Ramya; Singh, Vaishali; Low, Kok Yao; Chua, Chee Kai; Venkatraman, Subbu S

    2015-01-01

    A method has been developed to induce and retain a contractile phenotype for vascular smooth muscle cells, as the first step towards the development of a biomimetic blood vessel construct with minimal compliance mismatch. Melt spun PCL fibers were deposited on a mandrel to form aligned fibers of 10 μm in diameter. The fibers were bonded into aligned arrangement through dip coating in chitosan solution. This formed a surface of parallel grooves, 10 μm deep by 10 μm across, presenting a surface layer of chitosan to promote cell surface interactions. The aligned fiber surface was used to culture cells present in the vascular wall, in particular fibroblasts and smooth muscle cells. This topography induced "surface guidance" over the orientation of the cells, which adopted an elongated spindle-like morphology, whereas cells on the unpatterned control surface did not show such orientation, assuming more rhomboid shapes. The preservation of VSMC contractile phenotype on the aligned scaffold was demonstrated by the retention of α-SMA expression after several days of culture. The effect was assessed on a prototype vascular graft prosthesis fabricated from polylactide caprolactone; VSMCs aligned longitudinally along a fiberless tube, whereas, for the aligned fiber coated tubes, the VSMCs aligned in the required circumferential orientation. PMID:26413093

  9. A complex immune response in halo nevi correlates with immune reactivity on infiltrated melanocytes, adjacent hair follicles and blood vessels

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2014-10-01

    Full Text Available Introduction: A clinical “halo nevus” is a benign melanocytic-neoplasm, often exhibiting spontaneous involution. A characteristic clinical feature is depigmentation of the surrounding skin, and a centripetal progression of the tumor regression phenomenon. Case Report: An 18 year old male consulted the dermatologist for changes in color of an asymptomatic mole. Materials and Methods: A clinical evaluation was performed, and skin biopsies were obtained for hematoxylin and eosin (H&E review, and for immunohistochemical (IHC studies including CD3, CD4, CD8, CD20, CD68, CD99, myeloid/histiocyte antigen, S-100, PNL2 and SOX-10. Results: A neoplastic process was identified on H&E examination, located along the dermal/epidermal junction and within the dermis. The neoplasm was composed of nests, cords and strands of benign melanocytes, with infiltrating lymphocytes. IHC staining demonstrated a strong pattern of positivity with all of the IHC antibodies within, infiltrating and surrounding the primary neoplastic process. In addition, evidence of the primary tumor immune response was noted around surrounding blood vessels and hair follicles, and on adjacent epidermal melanocytes. Conclusions: In the present study, we demonstrate by histopathologic and immunologic evidence that lymphocytes are primarily responsible for halo nevus tumor regression. Moreover, the immune response involves not only CD8 positive T lymphocytes, but a larger spectrum of B and T lineage lymphocytes. Thus, the immunologic foundations of halo nevus regression are likely of greater complexity than previously determined..

  10. Continuous monitoring of absolute cerebral blood flow by near-infrared spectroscopy during global and focal temporary vessel occlusion.

    Science.gov (United States)

    Cooper, Joel A; Tichauer, Kenneth M; Boulton, Melfort; Elliott, Jonathan; Diop, Mamadou; Arango, Miguel; Lee, Ting-Yim; St Lawrence, Keith

    2011-06-01

    Treatment of intracranial aneurysms by surgical clipping carries a risk of intraoperative ischemia, caused mainly by prolonged temporary occlusion of cerebral arteries. The objective of this study was to develop a near-infrared spectroscopy (NIRS) technique for continuous monitoring of cerebral blood flow (CBF) during surgery. With this approach, cerebral hemodynamics prior to clipping are measured by a bolus-tracking method that uses indocyanine green as an intravascular contrast agent. The baseline hemodynamic measurements are then used to convert the continuous Hb difference (HbD) signal (HbD = oxyhemoglobin - deoxyhemoglobin) acquired during vessel occlusion to units of CBF. To validate the approach, HbD signal changes, along with the corresponding CBF changes, were measured in pigs following occlusion of the common carotid arteries or a middle cerebral artery. For both occlusion models, the predicted CBF change derived from the HbD signal strongly correlated with the measured change in CBF. Linear regression of the predicted and measured CBF changes resulted in a slope of 0.962 (R(2) = 0.909) following carotid occlusion and 0.939 (R(2) = 0.907) following middle cerebral artery occlusion. These results suggest that calibrating the HbD signal by baseline hemodynamic measurements provides a clinically feasible method of monitoring CBF changes during neurosurgery. PMID:21454747

  11. Mathematical Modelling of a Brain Tumour Initiation and Early Development: A Coupled Model of Glioblastoma Growth, Pre-Existing Vessel Co-Option, Angiogenesis and Blood Perfusion.

    Directory of Open Access Journals (Sweden)

    Yan Cai

    Full Text Available We propose a coupled mathematical modelling system to investigate glioblastoma growth in response to dynamic changes in chemical and haemodynamic microenvironments caused by pre-existing vessel co-option, remodelling, collapse and angiogenesis. A typical tree-like architecture network with different orders for vessel diameter is designed to model pre-existing vasculature in host tissue. The chemical substances including oxygen, vascular endothelial growth factor, extra-cellular matrix and matrix degradation enzymes are calculated based on the haemodynamic environment which is obtained by coupled modelling of intravascular blood flow with interstitial fluid flow. The haemodynamic changes, including vessel diameter and permeability, are introduced to reflect a series of pathological characteristics of abnormal tumour vessels including vessel dilation, leakage, angiogenesis, regression and collapse. Migrating cells are included as a new phenotype to describe the migration behaviour of malignant tumour cells. The simulation focuses on the avascular phase of tumour development and stops at an early phase of angiogenesis. The model is able to demonstrate the main features of glioblastoma growth in this phase such as the formation of pseudopalisades, cell migration along the host vessels, the pre-existing vasculature co-option, angiogenesis and remodelling. The model also enables us to examine the influence of initial conditions and local environment on the early phase of glioblastoma growth.

  12. Mathematical Modelling of a Brain Tumour Initiation and Early Development: A Coupled Model of Glioblastoma Growth, Pre-Existing Vessel Co-Option, Angiogenesis and Blood Perfusion.

    Science.gov (United States)

    Cai, Yan; Wu, Jie; Li, Zhiyong; Long, Quan

    2016-01-01

    We propose a coupled mathematical modelling system to investigate glioblastoma growth in response to dynamic changes in chemical and haemodynamic microenvironments caused by pre-existing vessel co-option, remodelling, collapse and angiogenesis. A typical tree-like architecture network with different orders for vessel diameter is designed to model pre-existing vasculature in host tissue. The chemical substances including oxygen, vascular endothelial growth factor, extra-cellular matrix and matrix degradation enzymes are calculated based on the haemodynamic environment which is obtained by coupled modelling of intravascular blood flow with interstitial fluid flow. The haemodynamic changes, including vessel diameter and permeability, are introduced to reflect a series of pathological characteristics of abnormal tumour vessels including vessel dilation, leakage, angiogenesis, regression and collapse. Migrating cells are included as a new phenotype to describe the migration behaviour of malignant tumour cells. The simulation focuses on the avascular phase of tumour development and stops at an early phase of angiogenesis. The model is able to demonstrate the main features of glioblastoma growth in this phase such as the formation of pseudopalisades, cell migration along the host vessels, the pre-existing vasculature co-option, angiogenesis and remodelling. The model also enables us to examine the influence of initial conditions and local environment on the early phase of glioblastoma growth.

  13. Proton density differences in signal characteristics of multiple sclerosis plaques versus white matter lesions of small vessel disease and vasculitis on high-field strength MR images

    International Nuclear Information System (INIS)

    This paper determines if variations in signal intensity characteristics on multi-spin-echo images obtained with a high-field-strength magnet can be useful in differentiating demyelinating plaques of multiple sclerosis from other pathologic white matter processes due to small vessel disease and vasculities. Using the first of two multi-spin-echo images obtained with a General Electric 1.5-T magnet, the investigators compared signal intensity characteristics in 30 patients with a firm clinical diagnosis of multiple sclerosis versus a control group of 30 patients with a known clinical history of small-vessel disease and vasculitis are isodense to gray matter on proton-density images

  14. [The comparative role of computed tomography and magnetic resonance imaging in the diagnosis of extracapsular spread of malignant lymphomatous masses invading blood vessels].

    Science.gov (United States)

    Dobrovolskiene, Laima; Griniûtë, Rasa

    2003-01-01

    Aim of the study was to search for an optimal method an of investigation in diagnosis of extracapsular spread of the malignant lymphomas and invading the blood vessels. In the period of 1998 to 2002, 81 patients with malignant lymphomas with coverage of neck and body areas were examined in the Department of Tomography of Kaunas University of Medicine Hospital. It was performed by computed tomography (CT) and magnetic resonance imaging (MRI), with or without iv. application of contrast media. The data were processed with SPSS 10.1 (Statistical package for Social Sciences 10.1 for Windows), including application of chi(2), t-test. Specificity, sensitivity and diagnostic accuracy of CT and MRI methods were calculated and compared according to recommendations by Gefland D. W. and Ott D. J., 1985. Diagnosis of extracapsular spread of the lymphomatous tissue and invading the blood vessels was best performed by MR method (specificity, sensitivity, accuracy in this case 91-95%). Bolus CT angiography because of low resolution in the range of soft tissues, insufficient opacification of blood vessels with contrast medium and differences in blood flow was not informative enough (specificity, sensitivity, accuracy in this case 80-85%).

  15. A study on improvement of RANS analysis for erosion of density stratified layer of multicomponent gas by buoyant jet in a containment vessel

    International Nuclear Information System (INIS)

    The analysis on a density stratification layer consisting of multiple gases in the reactor containment vessel is important for the safety assessment of sever accidents. The Japan Atomic Energy Agency (JAEA) has started the project on the containment thermal hydraulics. We carried out Computational Fluid Dynamics (CFD) analyses in order to investigate the erosion of the density stratification layer by a vertical buoyant jet under this project. We used the Reynolds averaged numerical simulation (RANS) and Large eddy simulation (LES) models to analyze the erosion of a density stratification layer by a vertical buoyant jet in a small vessel which represents a containment vessel. This numerical study calculates the turbulent mixing of a two-component (air and helium) gas mixture. The turbulence models used for the RANS analyses are two types of k-ε models. The first model is the low Reynolds number k-ε model developed by Launder and Sharma. The second model is revised from the first model in order to accurately consider the turbulent production and damping in a stratification layer. The results have indicated that both the RANS and LES models simulate almost the same behavior of the erosion of the density stratification layer. While the erosion rate calculated by the low-Re k-ε model was faster than that of the LES model, the modified k-ε model could calculate the erosion rate similar to the LES result. (author)

  16. Blood Thinners

    Science.gov (United States)

    If you have some kinds of heart or blood vessel disease, or if you have poor blood flow to your brain, your doctor may recommend that you take a blood thinner. Blood thinners reduce the risk of heart ...

  17. Short-Term Blood Pressure Variability Relates to the Presence of Subclinical Brain Small Vessel Disease in Primary Hypertension.

    Science.gov (United States)

    Filomena, Josefina; Riba-Llena, Iolanda; Vinyoles, Ernest; Tovar, José L; Mundet, Xavier; Castañé, Xavier; Vilar, Andrea; López-Rueda, Antonio; Jiménez-Baladó, Joan; Cartanyà, Anna; Montaner, Joan; Delgado, Pilar

    2015-09-01

    Blood pressure (BP) variability is associated with stroke risk, but less is known about subclinical cerebral small vessel disease (CSVD). We aimed to determine whether CSVD relates to short-term BP variability independently of BP levels and also, whether they improve CSVD discrimination beyond clinical variables and office BP levels. This was a cohort study on asymptomatic hypertensives who underwent brain magnetic resonance imaging and 24-hour ambulatory BP monitoring. Office and average 24-hour, daytime and nighttime BP levels, and several metrics of BP variability (SD, weighted SD, coefficient of variation, and average real variability [ARV]) were calculated. Definition of CSVD was based on the presence of lacunar infarcts and white matter hyperintensity grades. Multivariate analysis and integrated discrimination improvement were performed to assess whether BP variability and levels were independently associated with CSVD and improved its discrimination. Four hundred eighty-seven individuals participated (median age, 64; 47% women). CSVD was identified in 18.9%, related to age, male sex, diabetes mellitus, use of treatment, ambulatory BP monitoring-defined BP levels, and ARV of systolic BP at any period. The highest prevalence (33.7%) was found in subjects with both 24-hour BP levels and ARV elevated. BP levels at any period and ARV (24 hours and nocturnal) emerged as independent predictors of CSVD, and discrimination was incrementally improved although not to a clinically significant extent (integrated discrimination improvement, 5.31%, 5.17% to 5.4%). Ambulatory BP monitoring-defined BP levels and ARV of systolic BP relate to subclinical CSVD in hypertensive individuals.

  18. New Strain Energy Functions of Blood Vessel (Ⅰ)%血管的新应变能函数(Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    王寿梅; 李宁; 徐明

    2001-01-01

    首先提出并且验证了可被应用于大变形计算的描述血管非线性应力-应变关系的新的本构理论.其推导的数学基础是假设应力-应变关系可以用张量多项式来表示.通过对比可以发现,拟合结果与试验数据完全吻合,并且优于已有的指数形式的表达式.为降低Taylor展开式的次数,对级数进行了修正,并且针对不同的拟合过程和方法进行了讨论.%Investigation of the consequence of large deformation of blood vessel due to change in transmural pressure is crucial to the understanding of vein graft or other surgical operations involving blood vessel. The paper proposes and verifies new constitutive laws describing nonlinear stress-strain relation of orthogonal anisotropic materials. It can be used for large deformation calculation of blood vessels in the bio-mechanics regime. The derivation of the constitutive law is pure mathematical reasoning based on only one assumption that the stress-strain relation takes a polynomial form. Application is made in a blood vessel test. The correlation between the proposed formula and experimental data is excellent and better than that of the existing exponential expressions

  19. Lack of correlation of glucose levels in filtered blood plasma to density and conductivity measurements.

    Science.gov (United States)

    Gordon, David M; Ash, Stephen R

    2009-01-01

    The purpose of this research project was to determine whether the glucose level of a blood plasma sample from a diabetic patient could be predicted by measuring the density and conductivity of ultrafiltrate of plasma created by a 30,000 m.w. cutoff membrane. Conductivity of the plasma filtrate measures electrolyte concentration and should correct density measurements for changes in electrolytes and water concentration. In vitro studies were performed measuring conductivity and density of solutions of varying glucose and sodium chloride concentrations. Plasma from seven hospitalized patients with diabetes was filtered across a 30,000 m.w. cutoff membrane. The filtrate density and conductivity were measured and correlated to glucose levels. In vitro studies confirmed the ability to predict glucose from density and conductivity measurements, in varying concentrations of glucose and saline. In plasma filtrate, the conductivity and density measurements of ultrafiltrate allowed estimation of glucose in some patients with diabetes but not others. The correlation coefficient for the combined patient data was 0.45 which was significant but only explained 20% of the variability in the glucose levels. Individually, the correlation was significant in only two of the seven patients with correlation coefficients of 0.79 and 0.88. The reasons for lack of correlation are not clear, and cannot be explained by generation of idiogenic osmoles, effects of alcohol dehydrogenase, water intake, etc. This combination of physical methods for glucose measurement is not a feasible approach to measuring glucose in plasma filtrate.

  20. 人工血管材料血液相容性及表面改性%Hemocompatibility and surface modification of artificial blood vessel materials

    Institute of Scientific and Technical Information of China (English)

    何艳平; 马德春; 李磊; 张丽; 郑爽; 董可欣

    2015-01-01

    BACKGROUND:Artificial blood vessels made from synthetic materials are the most commonly used blood vessel substitutes. How to improve the patency of the blood vessels and the compatibility of artificial blood vessel materials is in the focus of research in recent years. OBJECTIVE:To review the biocompatibility and hemocompatiblity of artificial blood vessel materials, and to summarize a number of new methods and viewpoints appearing in international biomaterial and blood interaction research in recent years. METHODS: Wanfang database, Chinese Journal Ful-text Database and PubMed database were retrieved by the first author for relevant articles published from 2001 to 2014, using the key words of “artificial blood vessels, biomaterials” in Chinese and English, respectively. RESULTS AND CONCLUSION: Research on the hemocompatibility of materials, although after many years, is stil in the exploratory stage. There are many factors influencing material hemocompatibility, and in addition to the inherent blood components, surface and interface characteristics of the materials play a decisive role. Currently, surface and interface features optimization and modification has become an important way to improve the blood compatibility, but the existing evaluation system appears to have some problems, such as the selection and quantitative evaluation of sensitive indicators and positive control materials. Therefore, to develop artificial materials with good hemocompatibility and to establish rational and high-efficient blood compatibility evaluation system stil need further studies.%背景:人工血管取于合成材料,是最常用的血管代用品,如何提高血管的通畅性和人工血管材料的相容性是在近年来人工血管研究的重点。目的:综述人工血管材料的生物相容性和血液相容性,归纳近年来国际在生物材料和血液相互作用研究方面出现的一些新方法和视点。方法:由第一作者用计算机检

  1. IgG BULLOUS PEMPHIGOID WITH ANTIBODIES TO IgD, DERMAL BLOOD VESSELS, ECCRINE GLANDS AND THE ENDOMYSIUM OF MONKEY ESOPHAGUS

    Directory of Open Access Journals (Sweden)

    Abreu Velez Ana Maria

    2011-04-01

    Full Text Available Context: Bullous pemphigoid is mediated by autoantibodies primarily targeting two structural proteins of basement membrane hemidesmosomes, BP180 (BPAG2; collagen XVII and BP230 (BPAG1. Case Report: A 70-year-old Caucasian male patient was evaluated for a seven day history of multiple itching, erythematous blisters on his extremities. Biopsies for hematoxylin and eosin examination, direct immunofluorescence and indirect immunofluorescence (including salt split skin analysis were performed. Results: Hematoxylin and eosin examination demonstrated a subepidermal blister. Within the blister lumen, numerous eosinophils and lymphocytes were noted. Direct and indirect immunofluorescence revealed linear deposits of IgG, Complement/C3 and fibrinogen at the basement membrane zone of the skin and surrounding selected dermal blood vessels and sweat glands. Positive intracytoplasmic staining for anti-human IgD was noted in most of the epidermis, as well as surrounding some dermal blood vessels. Indirect immunofluorescence utilizing monkey esophagus substrate demonstrated strong positivity within the endomysium for IgG antibodies. Conclusion: We report a unique case of bullous pemphigoid with reactivity to eccrine sweat glands, and selected dermal blood vessels. In addition, the observed reactivity of anti-human IgD, and of IgG to monkey esophagus endomysium warrant further investigation.

  2. Effect of monounsaturated fatty acids on high-density and low-density lipoprotein cholesterol levels and blood pressure in healthy men and women.

    NARCIS (Netherlands)

    Mensink, R.P.

    1990-01-01

    The purpose of the studies described in this thesis was to examine the effect of monounsaturated fatty acids on the distribution of serum cholesterol over high-density and low-density lipoproteins (HDL and LDL) and on blood pressure in healthy men and women. High levels of LDL cholesterol and bl

  3. PDGF-C induces maturation of blood vessels in a model of glioblastoma and attenuates the response to anti-VEGF treatment.

    Directory of Open Access Journals (Sweden)

    Emmanuelle di Tomaso

    Full Text Available Recent clinical trials of VEGF inhibitors have shown promise in the treatment of recurrent glioblastomas (GBM. However, the survival benefit is usually short-lived as tumors escape anti-VEGF therapies. Here we tested the hypothesis that Platelet Derived Growth Factor-C (PDGF-C, an isoform of the PDGF family, affects GBM progression independent of VEGF pathway and hinders anti-VEGF therapy.We first showed that PDGF-C is present in human GBMs. Then, we overexpressed or downregulated PDGF-C in a human GBM cell line, U87MG, and grew them in cranial windows in nude mice to assess vessel structure and function using intravital microscopy. PDGF-C overexpressing tumors had smaller vessel diameters and lower vascular permeability compared to the parental or siRNA-transfected tumors. Furthermore, vessels in PDGF-C overexpressing tumors had more extensive coverage with NG2 positive perivascular cells and a thicker collagen IV basement membrane than the controls. Treatment with DC101, an anti-VEGFR-2 antibody, induced decreases in vessel density in the parental tumors, but had no effect on the PDGF-C overexpressing tumors.These results suggest that PDGF-C plays an important role in glioma vessel maturation and stabilization, and that it can attenuate the response to anti-VEGF therapy, potentially contributing to escape from vascular normalization.

  4. Blood vessel hyperpermeability and pathophysiology in human tumour xenograft models of breast cancer: a comparison of ectopic and orthotopic tumours

    International Nuclear Information System (INIS)

    Human tumour xenografts in immune compromised mice are widely used as cancer models because they are easy to reproduce and simple to use in a variety of pre-clinical assessments. Developments in nanomedicine have led to the use of tumour xenografts in testing nanoscale delivery devices, such as nanoparticles and polymer-drug conjugates, for targeting and efficacy via the enhanced permeability and retention (EPR) effect. For these results to be meaningful, the hyperpermeable vasculature and reduced lymphatic drainage associated with tumour pathophysiology must be replicated in the model. In pre-clinical breast cancer xenograft models, cells are commonly introduced via injection either orthotopically (mammary fat pad, MFP) or ectopically (subcutaneous, SC), and the organ environment experienced by the tumour cells has been shown to influence their behaviour. To evaluate xenograft models of breast cancer in the context of EPR, both orthotopic MFP and ectopic SC injections of MDA-MB-231-H2N cells were given to NOD scid gamma (NSG) mice. Animals with matched tumours in two size categories were tested by injection of a high molecular weight dextran as a model nanocarrier. Tumours were collected and sectioned to assess dextran accumulation compared to liver tissue as a positive control. To understand the cellular basis of these observations, tumour sections were also immunostained for endothelial cells, basement membranes, pericytes, and lymphatic vessels. SC tumours required longer development times to become size matched to MFP tumours, and also presented wide size variability and ulcerated skin lesions 6 weeks after cell injection. The 3 week MFP tumour model demonstrated greater dextran accumulation than the size matched 5 week SC tumour model (for P < 0.10). Immunostaining revealed greater vascular density and thinner basement membranes in the MFP tumour model 3 weeks after cell injection. Both the MFP and SC tumours showed evidence of insufficient lymphatic drainage

  5. 钙通道阻滞剂对神经损伤后瘢痕处血管分布的影响%Effects of calcium channel blockers on the distribution of blood vessels around the scar after nerve injury

    Institute of Scientific and Technical Information of China (English)

    刘冲; 刘晓峰; 陈涛平; 王云飞; 任宝; 郭召; 薛金伟; 刘双立

    2015-01-01

    目的:探讨钙通道阻滞剂对大鼠坐骨神经损伤后瘢痕处血管分布的实验研究。方法选用SD大鼠96只,随机4组,每组24只,制作大鼠坐骨神经损伤模型,实验组及对照组每天分别给予腹腔注射维拉帕米和生理盐水(4 mg/kg),分别于术后第4、8周进行免疫组化染色及血管灌注,观察损伤后瘢痕处血管分布情况。结果术后4、8周实验组瘢痕处血管数量多、密度高,血管分布较均匀,血管走形较规律。对照组血管数量少,密度低,血管分布不均,血管走形紊乱。结论钙通道阻滞剂能够改变损伤处血管分布状况,改善损伤处神经组织的血液供应。%Objective To investigate the correlation between the calcium channel blockers on the distribution of blood vessels scar after sciatic nerve injury in rats.Methods 96 SD rats were divided into 4 group at random, 24 rats in each group. The experimental rats were made sciatic nerve injury model, the experimental group and control group were given respectively a intraperitoneal injection of verapamil and physiological saline(4 mg/kg), in 4, 8 weeks after surgery immunohistochemical staining and vascular perfusion were conducted to observe the scar after injury of vascular distribution.Results In 4, 8 weeks after surgery, the blood vessel numbers were increased and the density of the nerve lesions became higher, the vascular distributions were more uniform in the rats of the experimental group. However, the results of the controls indicated that the blood vessels numbers were decreased, the density of the nerve lesions became lower, the vascular distributions were in the state of disorder.Conclusion Calcium channel blockers can be used to reduce the formation of collagen ifbers to soften the scars, and thus improve the distribution of the lesions of blood vessels and promote the blood supply of nerve tissue damage, and make the damaged nerve bundle membrane and blood

  6. Low-density lipoprotein mimics blood plasma-derived exosomes and microvesicles during isolation and detection.

    Science.gov (United States)

    Sódar, Barbara W; Kittel, Ágnes; Pálóczi, Krisztina; Vukman, Krisztina V; Osteikoetxea, Xabier; Szabó-Taylor, Katalin; Németh, Andrea; Sperlágh, Beáta; Baranyai, Tamás; Giricz, Zoltán; Wiener, Zoltán; Turiák, Lilla; Drahos, László; Pállinger, Éva; Vékey, Károly; Ferdinandy, Péter; Falus, András; Buzás, Edit Irén

    2016-01-01

    Circulating extracellular vesicles have emerged as potential new biomarkers in a wide variety of diseases. Despite the increasing interest, their isolation and purification from body fluids remains challenging. Here we studied human pre-prandial and 4 hours postprandial platelet-free blood plasma samples as well as human platelet concentrates. Using flow cytometry, we found that the majority of circulating particles within the size range of extracellular vesicles lacked common vesicular markers. We identified most of these particles as lipoproteins (predominantly low-density lipoprotein, LDL) which mimicked the characteristics of extracellular vesicles and also co-purified with them. Based on biophysical properties of LDL this finding was highly unexpected. Current state-of-the-art extracellular vesicle isolation and purification methods did not result in lipoprotein-free vesicle preparations from blood plasma or from platelet concentrates. Furthermore, transmission electron microscopy showed an association of LDL with isolated vesicles upon in vitro mixing. This is the first study to show co-purification and in vitro association of LDL with extracellular vesicles and its interference with vesicle analysis. Our data point to the importance of careful study design and data interpretation in studies using blood-derived extracellular vesicles with special focus on potentially co-purified LDL. PMID:27087061

  7. Low-density lipoprotein mimics blood plasma-derived exosomes and microvesicles during isolation and detection.

    Science.gov (United States)

    Sódar, Barbara W; Kittel, Ágnes; Pálóczi, Krisztina; Vukman, Krisztina V; Osteikoetxea, Xabier; Szabó-Taylor, Katalin; Németh, Andrea; Sperlágh, Beáta; Baranyai, Tamás; Giricz, Zoltán; Wiener, Zoltán; Turiák, Lilla; Drahos, László; Pállinger, Éva; Vékey, Károly; Ferdinandy, Péter; Falus, András; Buzás, Edit Irén

    2016-04-18

    Circulating extracellular vesicles have emerged as potential new biomarkers in a wide variety of diseases. Despite the increasing interest, their isolation and purification from body fluids remains challenging. Here we studied human pre-prandial and 4 hours postprandial platelet-free blood plasma samples as well as human platelet concentrates. Using flow cytometry, we found that the majority of circulating particles within the size range of extracellular vesicles lacked common vesicular markers. We identified most of these particles as lipoproteins (predominantly low-density lipoprotein, LDL) which mimicked the characteristics of extracellular vesicles and also co-purified with them. Based on biophysical properties of LDL this finding was highly unexpected. Current state-of-the-art extracellular vesicle isolation and purification methods did not result in lipoprotein-free vesicle preparations from blood plasma or from platelet concentrates. Furthermore, transmission electron microscopy showed an association of LDL with isolated vesicles upon in vitro mixing. This is the first study to show co-purification and in vitro association of LDL with extracellular vesicles and its interference with vesicle analysis. Our data point to the importance of careful study design and data interpretation in studies using blood-derived extracellular vesicles with special focus on potentially co-purified LDL.

  8. 小口径人工血管支架材料:问题与前景%Small-caliber artificial blood vessels:problems and prospects

    Institute of Scientific and Technical Information of China (English)

    徐志伟; 谭燕; 吴昊; 李温斌

    2014-01-01

    BACKGROUND:Long-term patency rate of smal-caliber artificial blood vessels is stil the most important issue to be solved. OBJECTIVE:To review the materials and fabrication technologies of smal-caliber artificial blood vessels as wel as endothelialization of smal-caliber artificial blood vessels. METHODS:A computer-based search of PubMed (2000-2013) and Wanfang database (2003-2013) was done for relevant articles using the key words of“smal-caliber, vascular graft, electrospun, layer-by-layer assembly, endothelialization”in English and Chinese, respectively. A total of 125 articles were retrieved, and final y, 41 were included for further analysis. RESULTS AND CONCLUSION:At present, smal-caliber vascular graft materials include natural biological materials, biodegradable polymers, composite materials and xenogeneic biomaterials. Preparation technologies of smal-caliber artificial blood vessels mainly include electrospinning, self-assembly, rapid prototyping, and gel spinning. Numerous methods can elicit endothelialization of smal-caliber artificial blood vessels, but each method has its flaws and cannot ensure long-term patency radical y. With the development and diversification of preparation technologies and in-depth study of endothelialization of vascular prostheses, the long-term patency of smal-caliber artificial blood vessels wil gradual y be resolved.%背景:小口径人工血管移植后远期通畅率的问题仍然是目前亟待解决的首要问题。  目的:综述小口径人工血管支架材料及制备工艺、小口径人工血管的内皮化研究进展。  方法:应用计算机检索Pubmed数据库(2000至2013年)和万方数据库(2003至2013年)相关文献,中文检索词为“人工血管,小口径,制备,静电纺丝,自组装,内皮化”;英文检索词为“smal-caliber,vascular graft,electrospun,layer-by-layer assembly,endothelialization”。共检索到文献125篇,保留其中41篇进行总

  9. Microsurgical treatment of infected extremities after blood vessel prosthesis%人工血管移植感染的显微外科治疗

    Institute of Scientific and Technical Information of China (English)

    左中男; 于绍斌; 左熙; 靳高峰; 杜永军; 杜学亮; 黎德规

    2009-01-01

    目的 报道人工血管移植感染显微外科治疗的临床疗效. 方法 从1998年1月至2008年12月,应用健侧肢体血管桥式交叉供血营养患肢治疗人工血管移植感染8例,其中股动、静脉4例.腘动、静脉2例,腋动、静脉2例. 结果 术后随访3年,所有肢体血液供应良好,肢体外形及功能恢复. 结论 应用健侧肢体血管桥式交叉供血营养患肢可有效恢复人工血管移植后感染肢体的血液供应,降低截肢率.%Objective To report the clinical effects of microsurgery in treatment of infected extremities after blood vessel prosthesis were transplanted.Methods From Jan.1998 to Dec.2008,8 cases of major vascular injuries in extremities were blood-supplied by cross bridge vascular anastomosis from uninjured extremities,including 4 cases of femoral artery and vein,2 cases of popliteal artery and vein,and 2 cases of brachial artery and vein. Results After 3 years of follow-up,blood circulation of infected extremities were reestablished in each of 8 cases,as well as function and appearance recovered.Conclusion The procedure of cross bridge vascular anastomosis from uninjured extremities may efficiently restitute the blood supply of the infected extremities after blood vessel prosthesis were transplanted,and decrease the rate of amputation.

  10. IgG/IgE bullous pemphigoid with CD45 lymphocytic reactivity to dermal blood vessels, nerves and eccrine sweat glands

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu-Velez

    2010-01-01

    Full Text Available Context: Bullous pemphigoid (BP, the most common autoimmune blistering disease, is mediated by autoantibodies. BP primarily affects the elderly and is characterized by the development of urticarial plaques surmounted by subepidermal blisters, and the deposition of immunoglobulins and complement at the basement membrane zone (BMZ of the skin. BP is immunologically characterized by the development of autoantibodies targeting two structural proteins of the hemidesmosomes, BP180 (collagen XVII and BP230 (BPAG1. Case Report: A 63 -year-old Caucasian female patient was evaluated for a 4 day history of several itching, erythematous blisters on her extremities. Biopsies for hematoxylin and eosin (H&E examination, as well as Periodic acid-Schiff (PAS, immunohistochemistry (IHC and direct immunofluorescence (DIF analysis were performed. Results: H&E demonstrated a subepidermal blister, with partial re-epithelialization of the blister floor. Within the blister lumen, numerous neutrophils were present, with occasional eosinophils and lymphocytes also noted. Within the dermis, a mild, superficial, perivascular and periadnexal infiltrate of lymphocytes, histiocytes and occasional eosinophils was identified, with mild perivascular leukocytoclastic debris. The PAS stain was positive at the BMZ, and around selected blood vessels, nerves and sweat glands. DIF revealed linear deposits of IgG and Complement/C3 and fibrinogen at the BMZ, and around selected dermal nerves, blood vessels and sweat glands. Strong granular deposits of IgE were also observed, colocalizing with monoclonal antibodies to Collagen IV (CIV. By IHC, positive CD45 staining of lymphocytes was seen surrounding selected dermal blood vessels, eccrine sweat glands, and nerves. Conclusion : The patient displayed IgG, IgE, and fibrinogen autoantibodies against the BMZ, as well as around some dermal nerves and sweat glands; their binding in the skin could trigger complement activation. In addition, the

  11. Data for the inhibition effects of recombinant lamprey CRBGP on the tube formation of HUVECs and new blood vessel generation in CAM models.

    Science.gov (United States)

    Jiang, Qi; Liu, Yu; Gou, Meng; Han, Jianmei; Wang, Jihong; Li, Qingwei; Xiao, Rong

    2016-03-01

    In the present data article, lamprey cysteine-rich buccal gland protein (CRBGP) which belongs to cysteine-rich secretory proteins (CRISPs) family was recombinant and expressed in Rosetta blue cells. After identification, the recombinant protein was purified through affinity chromatograph. The inhibition effects of recombinant lamprey CRBGP (rL-CRBGP) on tube formation of human umbilical vein endothelial cells (HUVECs) and new blood vessel generation in chick chorioallantoic membrane (CAM) models were analyzed. This paper contains data related to research concurrently published in "Anti-angiogenic activities of CRBGP from buccal glands of lampreys (Lampetra japonica)" [1]. PMID:26909383

  12. Data for the inhibition effects of recombinant lamprey CRBGP on the tube formation of HUVECs and new blood vessel generation in CAM models

    Directory of Open Access Journals (Sweden)

    Qi Jiang

    2016-03-01

    Full Text Available In the present data article, lamprey cysteine-rich buccal gland protein (CRBGP which belongs to cysteine-rich secretory proteins (CRISPs family was recombinant and expressed in Rosetta blue cells. After identification, the recombinant protein was purified through affinity chromatograph. The inhibition effects of recombinant lamprey CRBGP (rL-CRBGP on tube formation of human umbilical vein endothelial cells (HUVECs and new blood vessel generation in chick chorioallantoic membrane (CAM models were analyzed. This paper contains data related to research concurrently published in “Anti-angiogenic activities of CRBGP from buccal glands of lampreys (Lampetra japonica” [1].

  13. Development of a fast ultrasonic three-dimensional imaging system for diagnosing blood vessels of artificial-kidney-dialyzed patients

    Science.gov (United States)

    Akahane, Mutsuhiro; Mochizuki, Takashi; Yamashita, Yuko; Kasai, Chihiro; Kobayashi, Masayuki; Kishino, Osamu; Ogawa, Tomoya

    2001-05-01

    It is very important to observe the vessels of the patient who are dialyzed artificially. An X-ray examination using contrast medium injected to the patient has been used for this purpose up to the present, but sometimes the examination has a risk of radiation damage. Therefore, we developed a safe and easy-to-use system in which 3D images of the vessels in the patients are reconstructed very quick from ultrasonic echoes. In this system, a view point for 3D rendering is set on the above position of the ultrasonic transducer, and a ray for the rendering is coincided with an ultrasonic beam. These features enable 3D images to be gradually reconstructed in real time while the echoes are being received. A magnetic position sensor system and a special 3D scanner which was developed were adopted for acquiring 3D echo data. In signal processing, intensity inversion technology is carried out before the 3D rendering process in order to detect and emphasize the vessels. With this system, we have acquired echo signals from the vessels in the arm of kidney dialyzed patients and made similar 3D images of X-ray angiography with the echoes in a short time such as 4 to 8 seconds.

  14. Blood (For Parents)

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy Blood KidsHealth > For Parents > Blood Print A A A ... about the mysterious, life-sustaining fluid called blood. Blood Basics Two types of blood vessels carry blood ...

  15. Role of macrophages and lymphocytes in morphogenesis of features of blood vessel in patients with metabolic syndrome complicated by stroke

    OpenAIRE

    Chuiko N.Ya.

    2013-01-01

    Background. The main morphological substrate of arterial disease in the metabolic syndrome is atherosclerosis, which morphogenesis is studied insufficiently. Objective. To estimate the role of macrophages and lymphocytes in the morphogenesis of changes of cerebral arteries in patients with metabolic syndrome complicated by ischemic and hemorrhagic stroke. Methods. We investigated brain vessels of 30 deaths from ischemic stroke, 30 - with hemorrhagic stroke on the background of metabolic syndr...

  16. Thiazine Red(+) platelet inclusions in Cerebral Blood Vessels are first signs in an Alzheimer's Disease mouse model.

    Science.gov (United States)

    Kniewallner, Kathrin M; Wenzel, Daniela; Humpel, Christian

    2016-01-01

    Strong evidence shows an association between cerebral vascular diseases and Alzheimer´s disease (AD). In order to study the interaction of beta-amyloid (Aβ) plaques with brain vessels, we crossbred an AD mouse model (overexpressing amyloid precursor protein with the Swedish-Dutch-Iowa mutations, APP_SweDI) with mice expressing green fluorescent protein (GFP) under the flt-1/VEGFR1 promoter in vessels (GFP_FLT1). Our data show, that only very few Aβ plaques were seen in 4-months old mice, focused in the mammillary body and in the lateral septal nucleus. The number of plaques markedly increased with age being most prominent in 12-months old mice. Thiazine Red was used to verify the plaques. Several Thiazine Red(+) inclusions were found in GFP(+) vessels, but only in non-perfused 4-months old mice. These inclusions were verified by Resorufin stainings possibly representing cerebral amyloid angiopathy. The inclusions were also seen in non-crossbred APP_SweDI but not in wildtype and GFP_FLT1 mice. In order to characterize these inclusions Flow Cytometry (FACS) analysis demonstrated that platelets were specifically stained by Thiazine Red(+), more pronounced when aggregated. In conclusion, our data show that Thiazine Red(+) inclusions representing aggregated platelets are a first pathological sign in AD before plaque development and may become important therapeutic targets in early AD. PMID:27345467

  17. The use of fractal dimension analysis in estimation of blood vessels shape in transplantable mammary adenocarcinoma in Wistar rats after photodynamic therapy combined with cysteine protease inhibitors.

    Science.gov (United States)

    Jurczyszyn, Kamil; Osiecka, Beata J; Ziółkowski, Piotr

    2012-01-01

    Fractal dimension analysis (FDA) is modern mathematical method widely used to describing of complex and chaotic shapes when classic methods fail. The main aim of this study was evaluating the influence of photodynamic therapy (PDT) with cystein proteases inhibitors (CPI) on the number and morphology of blood vessels inside tumor and on increase of effectiveness of combined therapy in contrast to PDT and CPI used separately. Animals were divided into four groups: control, treated using only PDT, treated using only CPI and treated using combined therapy, PDT and CPI. Results showed that time of animal survival and depth of necrosis inside tumor were significantly higher in CPI+PDT group in contrast to other groups. The higher value of fractal dimension (FD) was observed in control group, while the lowest value was found in the group which was treated by cystein protease inhibitors. The differences between FD were observed in CPI group and PDT+CPI group in comparison to control group. Our results revealed that fractal dimension analysis is a very useful tool in estimating differences between irregular shapes like blood vessels in PDT treated tumors. Thus, the implementation of FDA algorithms could be useful method in evaluating the efficacy of PDT.

  18. 组织工程人工血管的临床应用研究进展%Clinical testing for tissue engineering blood vessel

    Institute of Scientific and Technical Information of China (English)

    孙本义; 陈学明

    2008-01-01

    To seek the ideal replacing grafts of blood vessel,many different methods of tissue engineering blood vessel(TEBV)have been created,such as collagen gel-based,biodegradable scaffold-based,self-assembled vascular grafts,and peritoneal and pleural cavities as bioreactors to grow autologous vascular grafts,etc.Some TEBVs have partially or completely met the requirements for clinic,even have applied in clinic.In this article reviewed,the models with better characters in big animals and clinical tests,and discussed the current problems of TEBV and looked forward to future clinical application.%为了寻找理想的血管替代物,涌现很多组织工程血管构建方法 ,如动物蛋白凝胶支架细胞种植,可降解支架细胞种植,组织片层组装,胸、腹腔生物反应器管芯诱导等.有的已部分或完全满足临床应用条件或已应用于临床,本文对大动物试验和临床应用中表现性能较好的构建模型加以综述,并探讨目前研究中的问题及对未来的展望.

  19. Validation of a method to differentiate arterial and venous vessels in CT perfusion data using linear combinations of quantitative time-density curve characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Havla, Lukas; Schneider, Moritz; Dietrich, Olaf [Ludwig-Maximilians-University Hospital Munich, Josef Lissner Laboratory for Biomedical Imaging, Institute for Clinical Radiology, Munich (Germany); Thierfelder, Kolja M.; Beyer, Sebastian E.; Ertl-Wagner, Birgit; Sommer, Wieland H. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany)

    2015-10-15

    We aimed to develop and evaluate a new method that reliably differentiates between cerebral arteries and veins using voxel-wise CT-perfusion-derived parameters. Fourteen consecutive patients with suspected stroke but without pathological findings were examined on a multi-detector CT system: 32 dynamic phases (∇t = 1.5 s) during application of 35 mL iomeprol-350 were acquired at 80 kV/200mAs. Three hemodynamic parameters were calculated for 18 arterial and venous vessel segments: A (maximum of the time-density-curve), T (time-to-peak), and W (full-width-at-half-maximum). Using receiver operator characteristic (ROC) curve analysis and Fisher's linear discriminant analysis (FLDA), the performance of every classifier (A, T, W) and of all linear combinations for the differentiation of arterial and venous vessels was determined. A maximum area under the ROC-curve (AUC) of 0.945 (accuracy = 86.8 %) was obtained using the FLDA combination of A and T or the triplet FLDA of A and T and W for the classification of venous and arterial vessels. The best single parameter was T with an AUC of 0.871 (accuracy = 79.0 %), which performed significantly worse than the combination A and T (p < 0.001). Arteries and veins can be accurately differentiated based on dynamic CT perfusion data using the maximum of the time-density curve, its time-to-peak, its width, and FLDA combinations of these parameters, which yield accuracies up to 87 %. (orig.)

  20. Grading vascularity from histopathological images based on traveling salesman distance and vessel size

    Science.gov (United States)

    Niazi, M. Khalid Khan; Hemminger, Jessica; Kurt, Habibe; Lozanski, Gerard; Gurcan, Metin

    2014-03-01

    Vascularity represents an important element of tissue/tumor microenvironment and is implicated in tumor growth, metastatic potential and resistence to therapy. Small blood vessels can be visualized using immunohistochemical stains specific to vascular cells. However, currently used manual methods to assess vascular density are poorly reproducible and are at best semi quantitative. Computer based quantitative and objective methods to measure microvessel density are urgently needed to better understand and clinically utilize microvascular density information. We propose a new method to quantify vascularity from images of bone marrow biopsies stained for CD34 vascular lining cells protein as a model. The method starts by automatically segmenting the blood vessels by methods of maxlink thresholding and minimum graph cuts. The segmentation is followed by morphological post-processing to reduce blast and small spurious objects from the bone marrow images. To classify the images into one of the four grades, we extracted 20 features from the segmented blood vessel images. These features include first four moments of the distribution of the area of blood vessels, first four moments of the distribution of 1) the edge weights in the minimum spanning tree of the blood vessels, 2) the shortest distance between blood vessels, 3) the homogeneity of the shortest distance (absolute difference in distance between consecutive blood vessels along the shortest path) between blood vessels and 5) blood vessel orientation. The method was tested on 26 bone marrow biopsy images stained with CD34 IHC stain, which were evaluated by three pathologists. The pathologists took part in this study by quantifying blood vessel density using gestalt assessment in hematopoietic bone marrow portions of bone marrow core biopsies images. To determine the intra-reader variability, each image was graded twice by each pathologist with two-week interval in between their readings. For each image, the ground

  1. Vessel Operating Units (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data for vessels that are greater than five net tons and have a current US Coast Guard documentation number. Beginning in1979, the NMFS...

  2. Extracellular-purine metabolism in blood vessels (part I). Extracellular-purine level in blood of patients with abdominal aortic aneurysm.

    Science.gov (United States)

    Lecka, Joanna; Molski, Stanislaw; Komoszynski, Michal

    2010-09-01

    Adenosine and adenosine derivatives are the main regulators of purinoceptors (P1 and P2) mediated hemostasis and blood pressure. Since impaired hemostasis and high blood pressure lead to atherosclerosis and to the development of aneurysm, in this study we tested and compared the concentration of extracellular purines (e-purines) in the blood in of patients having abdominal aortic aneurysm with that from healthy volunteers. Whereas adenine nucleosides and nucleotides level in human blood plasma was analysed using reverse phase high performance liquid chromatography (HPLC), cholesterol concentration was estimated by an enzymatic assay. We did not find any correlation between e-purines concentration and the age of healthy volunteers. Furthermore, the sum level of e-purines (ATP, ADP, AMP, adenosine, and inosine) in the control group did not exceed 70 microM, while it was nearly two-fold higher in the blood of patients having abdominal aortic aneurysm, (123 microM). In a special case of people with Leriche Syndrome, a disease characterized by deep atherosclerotic changes, the e-purines level had further increased. Additionally, we also report typical atherosclerotic changes in the aorta using histological assays as well as total cholesterol rise. The significant rise in cholesterol concentration in the blood of the patients with abdominal aortas aneurysm, compared with the control groups, was not unique since 23% of the healthy people also exceeded the normal level of cholesterol. Therefore, our results strongly indicate that the estimation of e-purines concentration in the blood may serve as another indicator of atherosclerosis and warrant further consideration as a futuristic diagnostic tool.

  3. Corneal vascularization in the Florida manatee (Trichechus manatus latirostris) and three-dimensional reconstruction of vessels.

    Science.gov (United States)

    Harper, Jennifer Y; Samuelson, Don A; Reep, Roger L

    2005-01-01

    The cornea of the Florida manatee is unique and unusual in its anatomy in that blood vessels have been found throughout. In all other animal species, this is considered a pathological condition impeding vision, and is usually caused by injury or trauma. The purpose of this study was to more clearly describe corneal vascularization by examining the architecture through three-dimensional reconstruction in order to find possible patterns in size, distribution, and location of blood vessels relative to gender, age, location, and season. Twenty-six eyes from 22 individuals were prepared for histologic examination and subsequent three-dimensional reconstruction. Every specimen examined had blood vessels in the cornea, comprising an average of 0.3% of total surface density (volume) of the cornea. No differences were found between individuals based on gender, age, and season. Environmental influences were not a significant factor either, which was not originally anticipated. The presence of vessels at the level of the anterior epithelium was surprising and it appeared that the vascularization was directed more anteriorly than was originally thought. The presence of blood vessels in a prenatal eye was also found. In all the eyes examined, no signs of injury or trauma could be observed. The presence of blood vessels appears to minimally impair vision based on their low density, size, and location. The association of vessels with the anterior epithelium and development of vessels within the fetus point to an evolutionary adaptation possibly due to the manatee's unique ability to move between water bodies. PMID:15762922

  4. MR vascular fingerprinting: A new approach to compute cerebral blood volume, mean vessel radius, and oxygenation maps in the human brain.

    Science.gov (United States)

    Christen, T; Pannetier, N A; Ni, W W; Qiu, D; Moseley, M E; Schuff, N; Zaharchuk, G

    2014-04-01

    In the present study, we describe a fingerprinting approach to analyze the time evolution of the MR signal and retrieve quantitative information about the microvascular network. We used a Gradient Echo Sampling of the Free Induction Decay and Spin Echo (GESFIDE) sequence and defined a fingerprint as the ratio of signals acquired pre- and post-injection of an iron-based contrast agent. We then simulated the same experiment with an advanced numerical tool that takes a virtual voxel containing blood vessels as input, then computes microscopic magnetic fields and water diffusion effects, and eventually derives the expected MR signal evolution. The parameter inputs of the simulations (cerebral blood volume [CBV], mean vessel radius [R], and blood oxygen saturation [SO2]) were varied to obtain a dictionary of all possible signal evolutions. The best fit between the observed fingerprint and the dictionary was then determined by using least square minimization. This approach was evaluated in 5 normal subjects and the results were compared to those obtained by using more conventional MR methods, steady-state contrast imaging for CBV and R and a global measure of oxygenation obtained from the superior sagittal sinus for SO2. The fingerprinting method enabled the creation of high-resolution parametric maps of the microvascular network showing expected contrast and fine details. Numerical values in gray matter (CBV=3.1±0.7%, R=12.6±2.4μm, SO2=59.5±4.7%) are consistent with literature reports and correlated with conventional MR approaches. SO2 values in white matter (53.0±4.0%) were slightly lower than expected. Numerous improvements can easily be made and the method should be useful to study brain pathologies. PMID:24321559

  5. Unusual origin and potentially hazardous course of the major blood vessels in neck – A clinically relevant rare case

    Directory of Open Access Journals (Sweden)

    Rastogi R

    2010-04-01

    Full Text Available We present a rare case of aberrant left brachiocephalic vein and brachiocephalic artery, which crosses the trachea in the neck obliquely and closely related to lower border of thyroid gland. If not noticed while performing open or percutaneous dilatational tracheostomy or other neck surgeries, trauma to these vessel and subsequent hemorrhage can occur and may be fatal. Vascular compression of the airway causing obstructive symptoms can also occur due to this anomaly. In this report the case is presented along with its clinical significance.

  6. Experimental investigation of the functional behavior of blood vessels of the pulpa dentis with a semiconductor probe

    International Nuclear Information System (INIS)

    A nuclear medicine method is presented for blood circulation in the pulpa dentis, considering biological peculiarities. The beta emitting radiopharmaceutical DF32P (diisopropyl fluorophosphate) and specially prepared beagle teeth were used. The incorporated radioactivity was 350 to 750 μCi per animal. Measurements were performed with small semiconductor detector probes with lithium-coated silicon crystals from VEB MKD Dresden. The properties of the probes are described in detail. The results permit to draw conclusions with regard to the volume of blood circulation in the pulpa dentis under physiological and experimentally induced patho-physiological conditions. (author)

  7. Functional and pharmacological consequences of the distribution of voltage-gated calcium channels in the renal blood vessels

    DEFF Research Database (Denmark)

    Hansen, P B L

    2013-01-01

    -type is usually associated with vascular contractility. However, the L-, T- and P-/Q-types of calcium channels are present in the renal vasculature and are differentially involved in controlling vascular contractility, thereby contributing to regulation of kidney function and blood pressure. In the preglomerular...

  8. Identification of pro-angiogenic markers in blood vessels from stroked-affected brain tissue using laser-capture microdissection

    Directory of Open Access Journals (Sweden)

    Baldellou Maribel

    2009-03-01

    Full Text Available Abstract Background Angiogenesis correlates with patient survival following acute ischaemic stroke, and survival of neurons is greatest in tissue undergoing angiogenesis. Angiogenesis is critical for the development of new microvessels and leads to re-formation of collateral circulation, reperfusion, enhanced neuronal survival and improved recovery. Results Here, we have isolated active (CD105/Flt-1 positive and inactive (CD105/Flt-1 minus (n=5 micro-vessel rich-regions from stroke-affected and contralateral tissue of patients using laser-capture micro-dissection. Areas were compared for pro- and anti-angiogenic gene expression using targeted TaqMan microfluidity cards containing 46 genes and real-time PCR. Further analysis of key gene de-regulation was performed by immunohistochemistry to define localization and expression patterns of identified markers and de novo synthesis by human brain microvessel endothelial cells (HBMEC was examined following oxygen-glucose deprivation (OGD. Our data revealed that seven pro-angiogenic genes were notably up-regulated in CD105 positive microvessel rich regions. These were, beta-catenin, neural cell adhesion molecule (NRCAM, matrix metalloproteinase-2 (MMP-2, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1, hepatocyte growth factor-alpha (HGF-alpha, monocyte chemottractant protein-1 (MCP-1 and and Tie-2 as well as c-kit. Immunohistochemistry demonstrated strong staining of MMP-2, HGF-alpha, MCP-1 and Tie-2 in stroke-associated regions of active remodeling in association with CD105 positive staining. In vitro, OGD stimulated production of Tie-2, MCP-1 and MMP-2 in HBMEC, demonstrated a de novo response to hypoxia. Conclusion In this work we have identified concurrent activation of key angiogenic molecules associated with endothelial cell migration, differentiation and tube-formation, vessel stabilization and stem cell homing mechanisms in areas of revascularization. Therapeutic stimulation of these

  9. Computer simulation of MHD blood conveying gold nanoparticles as a third grade non-Newtonian nanofluid in a hollow porous vessel.

    Science.gov (United States)

    Hatami, M; Hatami, J; Ganji, D D

    2014-02-01

    In this paper, heat transfer and flow analysis for a non-Newtonian third grade nanofluid flow in porous medium of a hollow vessel in presence of magnetic field are simulated analytically and numerically. Blood is considered as the base third grade non-Newtonian fluid and gold (Au) as nanoparticles are added to it. The viscosity of nanofluid is considered a function of temperature as Vogel's model. Least Square Method (LSM), Galerkin method (GM) and fourth-order Runge-Kutta numerical method (NUM) are used to solve the present problem. The influences of the some physical parameters such as Brownian motion and thermophoresis parameters on non-dimensional velocity and temperature profiles are considered. The results show that increasing the thermophoresis parameter (N(t)) caused an increase in temperature values in whole domain and an increase in nanoparticles concentration just near the inner wall of vessel. Furthermore by increasing the MHD parameter, velocity profiles decreased due to magnetic field effect. PMID:24286727

  10. On the bifurcation of blood vessels--Wilhelm Roux's doctoral thesis (Jena 1878)--a seminal work for biophysical modelling in developmental biology.

    Science.gov (United States)

    Kurz, H; Sandau, K; Christ, B

    1997-02-01

    Wilhelm Roux's doctoral thesis described the relationship between the angle and diameter of bifurcating blood vessels. We have re-read this work in the light of biophysics and developmental biology and found two remarkable aspects hidden among a multitude of observations, rules and exceptions to these rules. First, the author identified the major determinants involved in vascular development; genetics, cybernetics, and mechanics; moreover, he knew that he could not deal with the genetic and regulatory aspects, and could hardly treat the mechanical part adequately. Second, he was deeply convinced that the laws of physics determine the design of organisms, and that a necessity for optimality was inherent in development. We combined the analysis of diameter relationships with the requirement for optimality in a stochastic biophysical model, and concluded that a constant wall-stress condition could define a minimum wall-tissue optimum during arterial development. Hence, almost 120 years after Wilhelm Roux's pioneering work, our model indicates one possible way in which physical laws have determined the evolution of regulatory and structural properties in vessel wall development. PMID:9059737

  11. Effect of silver nanoparticles and hydroxyproline, administered in ovo, on the development of blood vessels and cartilage collagen structure in chicken embryos

    DEFF Research Database (Denmark)

    Beck, Iwona; Hotowy, Anna; Sawosz, Ewa;

    2015-01-01

    It has been considered that concentrations of certain amino acids in the egg are not sufficient to fully support embryonic development of modern broilers. In this study we evaluated embryo growth and development with particular emphasis on one of the major components of connective tissue, collage......, in particular, the complex of AgHyp significantly increased blood vessel size, cartilage collagen fibre lattice size and bundle thickness. The general conclusion from this study is that AgHyp treatment may help to build a stronger and longer lasting form of collagen fibres....... microscopy was performed. Our results clearly indicate that Hyp, Ag and AgHyp administered in ovo to chicken embryos did not harm embryos. Comparing to the control group, Hyp, Ag and the AgHyp complex significantly upregulated expression of the FGF-2 at the mRNA and protein levels. Moreover, Hyp, Ag and...

  12. Ultrafine Fibrous Membranes by Coaxial Electrospinning for Artificial Blood Vessel%同轴电纺超细纤维膜构建人工血管材料

    Institute of Scientific and Technical Information of China (English)

    曹文轩; 张红; 袁晓燕

    2011-01-01

    以右旋糖酐(DEX)为芯、聚乙二醇-b-聚(L-丙交酯-co-ε-己内酯)(PELCL)为壳,采用同轴电纺技术制备DEX/PELCL超细纤维膜.在该电纺纤维内芯分别负载血管内皮生长因子(VEGF)和血小板衍生生长因子(PDGF-bb),并以此构建双层超细纤维膜人工血管支架.28 d的释放结果表明,VEGF和PDGF-bb 均表现出突释现象,含有肝素的VEGF样品释放量有所下降.大鼠腹主动脉移植实验结果表明,载有VEGF和PDGFbb的超细纤维膜可以用于构建双层人工血管.%Core/shell ultrafine fibers, with dextran(DEX) and poly(ethylene glycol)-b-poly(L-lactide-co-εcaprolactone) (PELCL) as the core and shell, respectively, were prepared by coaxial electrospinning.Double-layered ultraline fibrous tubes of the coaxial-electrospun DEX/PELCL fiberswere constructed for application as artificial blood vessel by loading vascular endothelial growth factor (VEGF) and platelet derived growth factor-bb( PDGF-bb), respectively in the fiber core. The in vitro releasing results of 28 d indicated that initial burst release occurred for both VEGF and PDGF-bb. The in vivo implantation in abdomen aorta of a rat model showed that the double-layered fibrous tubes loading VEGF and PDGF-bb could be potential used as artificial blood vessels.

  13. Flow measurements in a blood-perfused collagen vessel using x-ray micro-particle image velocimetry.

    Science.gov (United States)

    Antoine, Elizabeth; Buchanan, Cara; Fezzaa, Kamel; Lee, Wah-Keat; Rylander, M Nichole; Vlachos, Pavlos

    2013-01-01

    Blood-perfused tissue models are joining the emerging field of tumor engineering because they provide new avenues for modulation of the tumor microenvironment and preclinical evaluation of the therapeutic potential of new treatments. The characterization of fluid flow parameters in such in-vitro perfused tissue models is a critical step towards better understanding and manipulating the tumor microenvironment. However, traditional optical flow measurement methods are inapplicable because of the opacity of blood and the thickness of the tissue sample. In order to overcome the limitations of optical method we demonstrate the feasibility of using phase-contrast x-ray imaging to perform microscale particle image velocimetry (PIV) measurements of flow in blood perfused hydrated tissue-representative microvessels. However, phase contrast x-ray images significantly depart from the traditional PIV image paradigm, as they have high intensity background, very low signal-to-noise ratio, and volume integration effects. Hence, in order to achieve accurate measurements special attention must be paid to the image processing and PIV cross-correlation methodologies. Therefore we develop and demonstrate a methodology that incorporates image preprocessing as well as advanced PIV cross-correlation methods to result in measured velocities within experimental uncertainty.

  14. Flow measurements in a blood-perfused collagen vessel using x-ray micro-particle image velocimetry.

    Directory of Open Access Journals (Sweden)

    Elizabeth Antoine

    Full Text Available Blood-perfused tissue models are joining the emerging field of tumor engineering because they provide new avenues for modulation of the tumor microenvironment and preclinical evaluation of the therapeutic potential of new treatments. The characterization of fluid flow parameters in such in-vitro perfused tissue models is a critical step towards better understanding and manipulating the tumor microenvironment. However, traditional optical flow measurement methods are inapplicable because of the opacity of blood and the thickness of the tissue sample. In order to overcome the limitations of optical method we demonstrate the feasibility of using phase-contrast x-ray imaging to perform microscale particle image velocimetry (PIV measurements of flow in blood perfused hydrated tissue-representative microvessels. However, phase contrast x-ray images significantly depart from the traditional PIV image paradigm, as they have high intensity background, very low signal-to-noise ratio, and volume integration effects. Hence, in order to achieve accurate measurements special attention must be paid to the image processing and PIV cross-correlation methodologies. Therefore we develop and demonstrate a methodology that incorporates image preprocessing as well as advanced PIV cross-correlation methods to result in measured velocities within experimental uncertainty.

  15. Using non-linear analogue of Nyquist diagrams for analysis of the equation describing the hemodynamics in blood vessels near pathologies

    Science.gov (United States)

    Cherevko, A. A.; Bord, E. E.; Khe, A. K.; Panarin, V. A.; Orlov, K. J.; Chupakhin, A. P.

    2016-06-01

    This article considers method of describing the behaviour of hemodynamic parameters near vascular pathologies. We study the influence of arterial aneurysms and arteriovenous malformations on the vascular system. The proposed method involves using generalized model of Van der Pol-Duffing to find out the characteristic behaviour of blood flow parameters. These parameters are blood velocity and pressure in the vessel. The velocity and pressure are obtained during the neurosurgery measurements. It is noted that substituting velocity on the right side of the equation gives good pressure approximation. Thus, the model reproduces clinical data well enough. In regard to the right side of the equation, it means external impact on the system. The harmonic functions with various frequencies and amplitudes are substituted on the right side of the equation to investigate its properties. Besides, variation of the right side parameters provides additional information about pressure. Non-linear analogue of Nyquist diagrams is used to find out how the properties of solution depend on the parameter values. We have analysed 60 cases with aneurysms and 14 cases with arteriovenous malformations. It is shown that the diagrams are divided into classes. Also, the classes are replaced by another one in the definite order with increasing of the right side amplitude.

  16. Blood vessel hyperpermeability and pathophysiology in human tumour xenograft models of breast cancer: a comparison of ectopic and orthotopic tumours

    Directory of Open Access Journals (Sweden)

    Ho Karyn S

    2012-12-01

    Full Text Available Abstract Background Human tumour xenografts in immune compromised mice are widely used as cancer models because they are easy to reproduce and simple to use in a variety of pre-clinical assessments. Developments in nanomedicine have led to the use of tumour xenografts in testing nanoscale delivery devices, such as nanoparticles and polymer-drug conjugates, for targeting and efficacy via the enhanced permeability and retention (EPR effect. For these results to be meaningful, the hyperpermeable vasculature and reduced lymphatic drainage associated with tumour pathophysiology must be replicated in the model. In pre-clinical breast cancer xenograft models, cells are commonly introduced via injection either orthotopically (mammary fat pad, MFP or ectopically (subcutaneous, SC, and the organ environment experienced by the tumour cells has been shown to influence their behaviour. Methods To evaluate xenograft models of breast cancer in the context of EPR, both orthotopic MFP and ectopic SC injections of MDA-MB-231-H2N cells were given to NOD scid gamma (NSG mice. Animals with matched tumours in two size categories were tested by injection of a high molecular weight dextran as a model nanocarrier. Tumours were collected and sectioned to assess dextran accumulation compared to liver tissue as a positive control. To understand the cellular basis of these observations, tumour sections were also immunostained for endothelial cells, basement membranes, pericytes, and lymphatic vessels. Results SC tumours required longer development times to become size matched to MFP tumours, and also presented wide size variability and ulcerated skin lesions 6 weeks after cell injection. The 3 week MFP tumour model demonstrated greater dextran accumulation than the size matched 5 week SC tumour model (for P  Conclusions Dextran accumulation and immunostaining results suggest that small MFP tumours best replicate the vascular permeability required to observe the EPR effect

  17. A multicomponent bioactive tissue-engineered blood vessel: Fabrication, mechanical evaluation and biological evaluation with physiological-relevant conditions

    Science.gov (United States)

    Bonani, Walter

    The high long-term failure rate of synthetic vascular grafts in the replacement of small vessels is known to be associated with the lack of physiological signals to vascular cells causing adverse hemodynamic, inflammatory or coagulatory events. Current studies focus on developing engineered vascular devices with ability of directing cell activity in vitro and in vivo for tissue regeneration. It is also known that controlled molecule release from scaffolds can dramatically increase the scaffold ability of directing cell activities in vitro and in vivo for tissue regeneration. To address the mechanical and biological problems associated with graft materials, we demonstrated a degradable polyester-fibroin composite tubular scaffolds which shows well-integrated nanofibrous structure, endothelial-conducive surface and anisotropic mechanical property, suitable as engineered vascular constructs. Tissue regeneration needs not only functional biomolecules providing signaling cues to cells and guide tissue remodeling, but also an adequate modality of molecule delivery. In fact, healthy tissue formation requires specific signals at well-defined place and time. To develop scaffolds with multi-modal presentation of biomolecules, we patterned electrospun nanofibers over the thickness of the 3-dimensional scaffolds by programming the deposition of interpenetrating networks of degradable polymers poly(a-caprolactone) and poly(lactide-co-glycolide) acid in tailored proportion. Fluorescent model molecules, drug and growth factors were embedded in the polymeric fibers with different techniques and release profiles were obtained and discussed. Fabrication process resulted in precise gradient patterns of materials and functional biomolecules throughout the thickness of the scaffold. These graded materials showed programmable spatio-temporal control over the release. Molecule release profiles on each side of the scaffolds were used to determine the separation efficiency of molecule

  18. Single-step enrichment of basophils from human peripheral blood by a novel method using a Percoll density gradient.

    Science.gov (United States)

    Shiono, Hiroyuki; Matsui, Takuya; Okada, Tadashi; Ito, Yoichiro

    2016-08-01

    We have developed a novel continuous flow-through cell separation method using a Percoll density gradient. This method can continuously separate a large number of cells into five fractions according to their densities. To apply this method to the separation of basophils, Percoll density gradients were modified to improve basophil enrichment. When a set of Percoll density gradients was prepared (1.071, 1.075, 1.080, 1.084, and 1.090 g/mL) the basophils in a healthy volunteer were enriched by an average of 23.1 and 63.5% at Percoll densities of 1.075 (fraction 3) and 1.080 g/mL (fraction 4), respectively. On average, the yield of basophils was 1.66 × 10(5) cells in fraction 3 and 1.61 × 10(5) cells in fraction 4 from 9 mL of peripheral blood. The expression of CD203c (cluster of differentiation 203c) on separated basophils was upregulated by anti-immunoglobulin E stimulation similar to basophils in whole blood. Histamine release induced by calcium ionophore was also observed in the separated basophils. The present method will be useful for basophil enrichment since it preserves their function without using counterflow elutriation and immunological reagents, and this method will be effective as a preparative separation for cell purification by flow cytometry. PMID:27293108

  19. Remnant Cholesterol, Low-Density Lipoprotein Cholesterol, and Blood Pressure as Mediators From Obesity to Ischemic Heart Disease

    DEFF Research Database (Denmark)

    Varbo, Anette; Benn, Marianne; Smith, George Davey;

    2015-01-01

    RATIONALE: Obesity leads to increased ischemic heart disease (IHD) risk, but the risk is thought to be mediated through intermediate variables and may not be caused by increased weight per se. OBJECTIVE: To test the hypothesis that the increased IHD risk because of obesity is mediated through...... variables and using genetic variants associated with these. During ≤22 years of follow-up 13 945 participants developed IHD. The increased IHD risk caused by obesity was partly mediated through elevated levels of nonfasting remnant cholesterol and low-density lipoprotein cholesterol, through elevated blood...... obesity were low-density lipoprotein cholesterol with 8%, systolic blood pressure with 7%, and remnant cholesterol with 7% excess risk of IHD. Corresponding observational excess risks using conventional body mass index were 21%, 11%, and 20%, respectively. CONCLUSIONS: The increased IHD risk because...

  20. Blood flow dynamics in the snake spectacle.

    Science.gov (United States)

    van Doorn, Kevin; Sivak, Jacob G

    2013-11-15

    The eyes of snakes are shielded beneath a layer of transparent integument referred to as the 'reptilian spectacle'. Well adapted to vision by virtue of its optical transparency, it nevertheless retains one characteristic of the integument that would otherwise prove detrimental to vision: its vascularity. Given the potential consequence of spectacle blood vessels on visual clarity, one might expect adaptations to have evolved that mitigate their negative impact. Earlier research demonstrated an adaptation to their spatial layout in only one species to reduce the vessels' density in the region serving the foveal and binocular visual fields. Here, we present a study of spectacle blood flow dynamics and provide evidence of a mechanism to mitigate the spectacle blood vessels' deleterious effect on vision by regulation of blood flow through them. It was found that when snakes are at rest and undisturbed, spectacle vessels undergo cycles of dilation and constriction, such that the majority of the time the vessels are fully constricted, effectively removing them from the visual field. When snakes are presented with a visual threat, spectacle vessels constrict and remain constricted for longer periods than occur during the resting cycles, thus guaranteeing the best possible visual capabilities in times of need. Finally, during the snakes' renewal phase when they are generating a new stratum corneum, the resting cycle is abolished, spectacle vessels remain dilated and blood flow remains strong and continuous. The significance of these findings in terms of the visual capabilities and physiology of snakes is discussed.

  1. Blood Vessel Matrix Seeded with Cells: A Better Alternative for Abdominal Wall Reconstruction—A Long-Term Study

    Directory of Open Access Journals (Sweden)

    Maciej Nowacki

    2015-01-01

    Full Text Available Purpose. The aim of this study was to present abdominal wall reconstruction using a porcine vascular graft seeded with MSC (mesenchymal stem cells on rat model. Material and Methods. Abdominal wall defect was prepared in 21 Wistar rats. Acellular porcine-vascular grafts taken from aorta and prepared with Triton X were used. 14 aortic grafts were implanted in place, of which 7 grafts were seeded with rat MSC cells (Group I, and 7 were acellular grafts (Group II. As a control, 7 standard polypropylene meshes were used for defect augmentation (Group III. The assessment method was performed by HE and CD31 staining after 6 months. The mechanical properties have been investigated by Zwick&Roell Z0.5. Results. The strongest angiogenesis and lowest inflammatory response were observed in Group I. Average capillaries density was 2.75, 0.75, and 1.53 and inflammatory effect was 0.29, 1.39, and 2.72 for Groups I, II, and III, respectively. The means of mechanical properties were 12.74±1.48, 7.27±1.56, and 14.4±3.7 N/cm in Groups I and II and control, respectively. Conclusions. Cell-seeded grafts have better mechanical properties than acellular grafts but worse than polypropylene mesh. Cells improved mechanical and physiological properties of decellularized natural scaffolds.

  2. High blood pressure

    Science.gov (United States)

    ... you are at risk for: Bleeding from the aorta, the large blood vessel that supplies blood to ... tests Blood pressure check Blood pressure References American Diabetes Association. Standards of medical care in diabetes-2015 ...

  3. Phantom with Pulsatile Arteries to Investigate the Influence of Blood Vessel Depth on Pulse Oximeter Signal Strength

    Directory of Open Access Journals (Sweden)

    Hunor Santha

    2012-01-01

    Full Text Available This paper describes a three-layer head phantom with artificial pulsating arteries at five different depths (1.2 mm, 3.7 mm, 6.8 mm, 9.6 mm and 11.8 mm. The structure enables formation of spatially and temporally varying tissue properties similar to those of living tissues. In our experiment, pressure pulses were generated in the arteries by an electronically controlled pump. The physical and optical parameters of the layers and the liquid in the artificial arteries were similar to those of real tissues and blood. The amplitude of the pulsating component of the light returning from the phantom tissues was measured at each artery depth mentioned above. The build-up of the in-house-developed pulse oximeter used for performing the measurements and the physical layout of the measuring head are described. The radiant flux generated by the LED on the measuring head was measured to be 1.8 mW at 910 nm. The backscattered radiant flux was measured, and found to be 0.46 nW (0.26 ppm, 0.55 nW (0.31 ppm, and 0.18 nW (0.10 ppm for the 1.2 mm, 3.7 mm and 6.8 mm arteries, respectively. In the case of the 9.6 mm and 11.8 mm arteries, useful measurement data were not obtained owing to weak signals. We simulated the phantom with the arteries at the above-mentioned five depths and at two additional ones (2.5 mm and 5.3 mm in depth using the Monte Carlo method. The measurement results were verified by the simulation results. We concluded that in case of 11 mm source-detector separation the arteries at a depth of about 2.5 mm generate the strongest pulse oximeter signal level in a tissue system comprising three layers of thicknesses: 1.5 mm (skin, 5.0 mm (skull, and > 50 mm (brain.

  4. Chronic kidney disease, 24-h blood pressure and small vessel diseases are independently associated with cognitive impairment in lacunar infarct patients

    International Nuclear Information System (INIS)

    Although the relationships between chronic kidney disease (CKD) and cognitive impairment (CI) have been highlighted, the etiology of CI in CKD remains uncertain. Subjects comprised 224 consecutive patients with symptomatic lacunar infarction who underwent magnetic resonance imaging and ambulatory blood pressure monitoring (ABPM). Diurnal blood pressure (BP) patterns were categorized into three groups: dippers, non-dippers and risers. Lacunar infarcts (LIs), including both symptomatic and silent and diffuse white matter lesions (WMLs), were graded into three grades according to their degree. The results of kidney function were evaluated using estimated glomerular filtration rate (eGFR), categorized into three groups: stage 1, >60; stage 2, 30-60; and stage 3, -1 per 1.73 m2. There were 44 patients with CI. Confluent WMLs, including WML 2 and WML 3, were found in 36 patients (81.8%), and multiple lacunae including LI 2 and LI 3 were found in 30 patients (68.1%) with CI. Age >75 years (odds ratio (OR), 5.5; P-1 per 1.73 m2 (OR, 2.9; P-1 per 1.73 m2 (OR, 23.8; P75 years (OR, 4.1; P-1 per 1.73 m2 (OR, 3.7; P-1 per 1.73 m2 (OR, 8.7; P<0.05) were independently associated with WML grade 3. Extensive small vessel diseases, CKD and non-dipping status were independently associated with CI. CKD appears to mainly contribute to vascular CI, whereas possibilities of overlapping with other mechanisms such as degenerative CI cannot be excluded. Strict night time BP control and renoprotective treatment may be warranted to prevent CI. (author)

  5. 3D-Gd-DTPA MR angiography of cerebral blood vessels: A comparison with conventional 3D-MR subtraction angiography

    International Nuclear Information System (INIS)

    Subtraction angiography based on 3D fast imaging techniques using rephasing and dephasing gradient pulses is widely used, resulting in angiograms which closely correlate with DSA. Similar angiograms can be obtained with 3D-gradient echo techniques before and after the administration of Gadolinium (Gd)-DTPA (0.1-0.2 mmol/kg) followed by image subtraction. As Gd-DTPA does not penetrate the blood-brain barrier, brain imaging is not altering by the contrast agent. Both techniques were compared in patients wihout vascular disease, venous sinus thrombosis, AV malformation and aneurysm. With both techniques the cerebro-vascular system was imaged favoring the venous system because of the more constant flow velocity and the lack of ECG synchronization. Gd-DTPA offers the advantage of the higher signal-to-noise ratio and is hampered by background superposition due to Gd-DTPA enhancement in non brain tissue. With both techniques vessels down to 1 mm can be imaged. (orig.)

  6. Photogrammetric measurement and visualization of blood vessel branching casting: a tool for quantitative accuracy tests of MR, CT, and DS angiography

    Science.gov (United States)

    D'Apuzzo, Nicola

    2000-12-01

    Currently three different angiographic techniques are used to measure and visualize major blood vessels in the human body: magnetic resonance (MR), computer tomography (CT) and digital subtraction (DS) angiography. Although these imaging systems have been already qualitatively compared, a quantitative assessment is still missing. The goal of this work is to provide a tool enabling a quantitative comparison of the three imaging techniques to an unbiased reference. MR-, CT- and DS-angiographies are first performed on a corpse. Then, a casting of the abdominal aorta and its main branches is prepared, removed from the body and measured with photogrammetric methods. The elongated and thin cast is fixed in a 3D frame with 16 signalized small spheres used for calibration and orientation purposes. Three fixed CCD cameras acquire triplets of images of the casting, which is turned in 8 positions. In order to perform multi-image matching, an artificial random texture is projected onto the object. For each triplet of images, a semi-automated matching process based on least squares matching determines a dense set of corresponding points. Their 3D coordinates are then computed by forward intersection, with a mean standard deviation of about 0.2 mm. The result from the 8 positions are merged together into a 3D point cloud and an adequate filter is applied to remove the noise and the redundancy in the overlapping regions. The paper depicts the basic design of the system and the measurement methods. Furthermore some preliminary results are presented.

  7. Effect of silver nanoparticles and hydroxyproline, administered in ovo, on the development of blood vessels and cartilage collagen structure in chicken embryos.

    Science.gov (United States)

    Beck, Iwona; Hotowy, Anna; Sawosz, Ewa; Grodzik, Marta; Wierzbicki, Mateusz; Kutwin, Marta; Jaworski, Sławomir; Chwalibog, André

    2015-01-01

    It has been considered that concentrations of certain amino acids in the egg are not sufficient to fully support embryonic development of modern broilers. In this study we evaluated embryo growth and development with particular emphasis on one of the major components of connective tissue, collagen. Experiments were performed on Ross 308 chicken embryos from 160 fertilised eggs. Experimental solutions of silver nanoparticles (Ag), hydroxyproline solution (Hyp) and a complex of silver nanoparticles with hydroxyproline (AgHyp) were injected into albumen, and embryos were incubated until day 20. An assessment of the mass of embryo and selected organs was carried out followed by measurements of the expression of the key signalling factors' fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor-A (VEGF-A). Finally, an evaluation of collagen microstructure using scanning electron microscopy was performed. Our results clearly indicate that Hyp, Ag and AgHyp administered in ovo to chicken embryos did not harm embryos. Comparing to the control group, Hyp, Ag and the AgHyp complex significantly upregulated expression of the FGF-2 at the mRNA and protein levels. Moreover, Hyp, Ag and, in particular, the complex of AgHyp significantly increased blood vessel size, cartilage collagen fibre lattice size and bundle thickness. The general conclusion from this study is that AgHyp treatment may help to build a stronger and longer lasting form of collagen fibres. PMID:25530495

  8. The Sustained Delivery of Resveratrol or a Defined Grape Powder Inhibits New Blood Vessel Formation in a Mouse Model of Choroidal Neovascularization

    Directory of Open Access Journals (Sweden)

    Mozhgan Rezaie Kanavi

    2014-10-01

    Full Text Available The objective of this study was to determine whether resveratrol or a defined, reconstituted grape powder can attenuate the formation of new blood vessels in a mouse model of choroidal neovascularization (CNV. To accomplish this objective, C57BL/6J mice were randomized into control or treatment groups which received either resveratrol or grape powder by daily oral gavage, resveratrol or grape powder delivered ad libitum through the drinking water, or resveratrol by slow release via implanted osmotic pumps. A laser was used to rupture Bruch’s membrane to induce CNV which was then detected in sclerochoroidal eyecups stained with antibodies against intercellular adhesion molecule-2. CNV area was measured using fluorescence microscopy and Image J software. Ad libitum delivery of both resveratrol and grape powder was shown to significantly reduce the extent of CNV by 68% and 57%, respectively. Parallel experiments conducted in vitro demonstrated that resveratrol activates p53 and inactivates Akt/protein kinase B in choroidal endothelial cells, contributing to its anti-proliferative and anti-migratory properties. In addition resveratrol was shown to inhibit the formation of endothelial cell networks, augmenting its overall anti-angiogenic effects. The non-toxic nature of resveratrol makes it an especially attractive candidate for the prevention and/or treatment of CNV.

  9. High frame rate and high line density ultrasound imaging for local pulse wave velocity estimation using motion matching: A feasibility study on vessel phantoms.

    Science.gov (United States)

    Li, Fubing; He, Qiong; Huang, Chengwu; Liu, Ke; Shao, Jinhua; Luo, Jianwen

    2016-04-01

    Pulse wave imaging (PWI) is an ultrasound-based method to visualize the propagation of pulse wave and to quantitatively estimate regional pulse wave velocity (PWV) of the arteries within the imaging field of view (FOV). To guarantee the reliability of PWV measurement, high frame rate imaging is required, which can be achieved by reducing the line density of ultrasound imaging or transmitting plane wave at the expense of spatial resolution and/or signal-to-noise ratio (SNR). In this study, a composite, full-view imaging method using motion matching was proposed with both high temporal and spatial resolution. Ultrasound radiofrequency (RF) data of 4 sub-sectors, each with 34 beams, including a common beam, were acquired successively to achieve a frame rate of ∼507 Hz at an imaging depth of 35 mm. The acceleration profiles of the vessel wall estimated from the common beam were used to reconstruct the full-view (38-mm width, 128-beam) image sequence. The feasibility of mapping local PWV variation along the artery using PWI technique was preliminarily validated on both homogeneous and inhomogeneous polyvinyl alcohol (PVA) cryogel vessel phantoms. Regional PWVs for the three homogeneous phantoms measured by the proposed method were in accordance with the sparse imaging method (38-mm width, 32-beam) and plane wave imaging method. Local PWV was estimated using the above-mentioned three methods on 3 inhomogeneous phantoms, and good agreement was obtained in both the softer (1.91±0.24 m/s, 1.97±0.27 m/s and 1.78±0.28 m/s) and the stiffer region (4.17±0.46 m/s, 3.99±0.53 m/s and 4.27±0.49 m/s) of the phantoms. In addition to the improved spatial resolution, higher precision of local PWV estimation in low SNR circumstances was also obtained by the proposed method as compared with the sparse imaging method. The proposed method might be helpful in disease detections through mapping the local PWV of the vascular wall. PMID:26773791

  10. Citrus reticulata’s Peels Modulate Blood Cholesterol Profile and IncreaseBone Density of Ovariectomized Rats

    Directory of Open Access Journals (Sweden)

    Rosa Adelina

    2015-11-01

    Full Text Available Hormon Replacement Therapy is a common therapy for estrogen deficiency but in other side it will increase the risk of cardiovascular disease. Another alternative therapy which relatively more safe is using phytoestrogen. The Citrus reticulata’s peel contain flavanone and polimethoxyflavone which are suspected to give estrogenic effect, therefore it is potential to be used as phytoestrogen.The purpose of this study was to examine the estrogenic effect of Citrus reticulata’s peel extract in modulation of bone density and blood cholesterol profile of ovariectomized rats (OVX, an animal model of postmenopausal osteoporosis. Thirty six 7-weeks-old female Sprague Dawley rats were assigned to six groups: a SO group, an OVX group, an OVX+CMCNa group, an OVX+extract dose 500 mg/kgBW group, an OVX+extract dose 1000 mg/kgBW group, and an OVX+estradiol group. After 7 weeks, the rats were killed then blood and femoral were collected immediately. The rontgenogram indicated that extract and estradiol administration increase the bone density. And the data analysis with Oneway ANOVA test ,followed by Shceffé test (P 0.05 showed that extract can improve blood cholesterol profile in dose depend manner. These results suggest a possible role of Citrus reticulata’s peel extract as women’s health agent because of its beneficial effects on bone and lipids.

  11. Effect of cross-link density and hydrophilicity of PU on blood compatibility of hydrophobic PS/hydrophilic PU IPNs.

    Science.gov (United States)

    Roh, H W; Song, M J; Han, D K; Lee, D S; Ahn, J H; Kim, S C

    1999-01-01

    To investigate the effect of the hydrophilic and hydrophobic microdomain structure on blood compatibility, a series of interpenetrating polymer networks (IPNs) composed of hydrophilic polyurethane (PU) and hydrophobic polystyrene (PS) was prepared. One series was prepared with varying cross-link densities of each network, the other with varying hydrophilicity of the PU component. All PU/PS IPNs exhibited microphase-separated structures that had dispersed PS domains in the continuous PU matrix. The domain size decreased with decreasing the hydrophilicity of the PU component and increasing the cross-link density of each network. As the cross-link density and hydrophobicity of the PU component was increased, an inward shift of Tgs was observed, which was due to the decrease in phase separation between the hydrophobic PS component and hydrophilic PU component. In the in vitro platelet adhesion test, as the microdomain size of PU/PS IPN surface decreased, the number of adhered platelets on the PU/PS IPN surface was reduced and deformation of the adhered platelets decreased. It could be concluded that blood compatibility of PU/PS IPN was mainly affected by the degree of mixing between PU and PS component, which was reflected by the domain size of PS rich phase. PMID:10091927

  12. Low-density lipoprotein mimics blood plasma-derived exosomes and microvesicles during isolation and detection

    OpenAIRE

    Sódar, Barbara W; Ágnes Kittel; Krisztina Pálóczi; Vukman, Krisztina V; Xabier Osteikoetxea; Katalin Szabó-Taylor; Andrea Németh; Beáta Sperlágh; Tamás Baranyai; Zoltán Giricz; Zoltán Wiener; Lilla Turiák; László Drahos; Éva Pállinger; Károly Vékey

    2016-01-01

    Circulating extracellular vesicles have emerged as potential new biomarkers in a wide variety of diseases. Despite the increasing interest, their isolation and purification from body fluids remains challenging. Here we studied human pre-prandial and 4 hours postprandial platelet-free blood plasma samples as well as human platelet concentrates. Using flow cytometry, we found that the majority of circulating particles within the size range of extracellular vesicles lacked common vesicular marke...

  13. A Review of Retinal Vessel Segmentation Techniques and Algorithms

    OpenAIRE

    Mohd Imran Khan; Heena Shaikh; Anwar Mohd. Mansuri

    2011-01-01

    Retinal vessel segmentation algorithms are the critical components of circulatory blood vessel Analysis systems. We present a survey of vessel segmentation techniques and algorithms. We put the various vessel segmentation approaches and techniques in perspective by means of a classification of the existing research. While we have mainly targeted the segmentation of blood vessels, neurovascular structure in particular. We have divided vessel segmentation algorithms and techniques into six main...

  14. A novel bispecific immunotoxin delivered by human bone marrow-derived mesenchymal stem cells to target blood vessels and vasculogenic mimicry of malignant gliomas

    Directory of Open Access Journals (Sweden)

    Zhang Y

    2015-06-01

    Full Text Available Yonghong Zhang,1,2 Xinlin Sun,1 Min Huang,1 Yiquan Ke,1 Jihui Wang,1 Xiao Liu1 1National Key Clinic Specialty, Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 2Department of Neurosurgery, First Hospital of Lanzhou University, Lanzhou, People’s Republic of China Background: In previous years, immunotoxins have been shown to be a greatly promising therapeutic tool for brain malignancies, such as gliomas. Human mesenchymal stem cells (hMSCs exhibit tropism to tumor tissue. However, the effect of bispecific immunotoxins in malignant gliomas is still unknown. The aim of this study was to investigate the function of bispecific immunotoxins in human malignant gliomas.Materials and methods: In the present study, the bispecific immunotoxin VEGF165-ephrin A1-PE38KDEL was established using deoxyribonucleic acid shuffling and cloning techniques. The VEGF165-ephrin A1-PE38KDEL was delivered by hMSCs to mouse malignant gliomas. The effects of the bispecific immunotoxins on glioma-derived blood vessels and vasculogenic mimicry to elucidate the molecular mechanisms underlying the antitumorigenic effects of immunotoxins were examined in vivo.Results: In vitro, transfected hMSCs significantly inhibited the cell viability of gliomas cell lines U87 and U251 in a dose-dependent manner compared with untransfected hMSCs (P<0.01. In vivo, the intratumoral injection of engineered hMSCs was effective at inhibiting tumor growth in a malignant glioma tumor model.Conclusion: The bispecific immunotoxin secreted from hMSCs acts as a novel strategy for improving treatment options for malignant gliomas in the clinic. Keywords: bispecific immunotoxin, human mesenchymal stem cells, ephrin A1, VEGF165, malignant glioma

  15. Blood pressure regulation V: in vivo mechanical properties of precapillary vessels as affected by long-term pressure loading and unloading.

    Science.gov (United States)

    Eiken, Ola; Mekjavic, Igor B; Kölegård, Roger

    2014-03-01

    Recent studies are reviewed, concerning the in vivo wall stiffness of arteries and arterioles in healthy humans, and how these properties adapt to iterative increments or sustained reductions in local intravascular pressure. A novel technique was used, by which arterial and arteriolar stiffness was determined as changes in arterial diameter and flow, respectively, during graded increments in distending pressure in the blood vessels of an arm or a leg. Pressure-induced increases in diameter and flow were smaller in the lower leg than in the arm, indicating greater stiffness in the arteries/arterioles of the leg. A 5-week period of intermittent intravascular pressure elevations in one arm reduced pressure distension and pressure-induced flow in the brachial artery by about 50%. Conversely, prolonged reduction of arterial/arteriolar pressure in the lower body by 5 weeks of sustained horizontal bedrest, induced threefold increases of the pressure-distension and pressure-flow responses in a tibial artery. Thus, the wall stiffness of arteries and arterioles are plastic properties that readily adapt to changes in the prevailing local intravascular pressure. The discussion concerns mechanisms underlying changes in local arterial/arteriolar stiffness as well as whether stiffness is altered by changes in myogenic tone and/or wall structure. As regards implications, regulation of local arterial/arteriolar stiffness may facilitate control of arterial pressure in erect posture and conditions of exaggerated intravascular pressure gradients. That increased intravascular pressure leads to increased arteriolar wall stiffness also supports the notion that local pressure loading may constitute a prime mover in the development of vascular changes in hypertension.

  16. 基于结构特征的视网膜血管形态识别%Pattern recognition of retinal blood vessels based on nodes structure feature

    Institute of Scientific and Technical Information of China (English)

    赵晓芳; 林土胜

    2012-01-01

    针对视网膜眼底图像获取过程中眼球转动的问题,提出一种基于节点最近邻结构的具有旋转和平移不变性的视网膜血管形态识别方法.该方法利用节点的周边结构稳定性的特点来进行节点结构特征提取,进行图像相关结构匹配的判定.实验结果表明了该识别算法的有效性和可靠性,且不需要进行方位对准处理,具有较好地识别灵活性和实用性,正确识别率达到98.57%.%In order to overcome the effects of eye movement during the funds image acquisition stage, a method based on the node's adjacent structure for pattern recognition of retinal blood vessels is proposed. The method has the quality of rotation and translation invariance. Firstly, the node structure characteristics are extracted using the structural stability of the surrounding nodes, and then matching the image correlation structure. Experimental results on a database demonstrate the effectiveness and reliability of the recognition algorithm. It does not need to the complex pre-processing task for level alignment, and has a better adaptability and practicability. The accuracy rate of 98. 57 % is reached for the proposed method.

  17. The Changes of Retinal and Choroidal Blood Vessels of Congenital Glaucoma in Rabbits%兔先天性青光眼网络膜血管改变

    Institute of Scientific and Technical Information of China (English)

    张阳; 盖春柳; 徐洪斌; 马崇泽; 杨英

    2001-01-01

    Objective To investigate the ef fect of glaucoma on rabbitretinal and choroidal circulation.Methods Congenita l glaucoma group was composed of 5rabbits(7 eyes) of 24 months old,weighed 3.5 -4kg; control group: 10 rabbits with the same age; animal model group: 10 rabbits of 2 months old, weighted 2kg, its hyper tension developed by perfusing the anterior chamber with normal saline. Through the fundus photos and flash visual evoked potential (FVEP), we observed the sh apes of retinal and choroidal blood vessels, and the changes of FVEP. Flash electroretinogram (FERG) was used in the man -made acute hypertension rabbits.Results Compared with the control group, the retinal and choroidal vessel endings of co ngenital glaucoma rabbits were obviously decreased. In man-made acute hypertens i on rabbits, acute elevation of intraocular pressure (IOP) firstly caused the is chemia of retinal and choroidal vessel endings, with the large blood vessels thinned, even the blood flow discontinued. FVEP P100 latent period: con trol (83 ±9) ms, congenital glaucoma (112±14) ms, the difference was significant (p<0 .0 1) ; man-made acute hypertension: (69±5) ms before the elevation of IOP, (81 ±7 ) ms at 60-80mmHg, the wave was similar to a line at 100-130mmHg, (82±8)ms at 2 hours after IOP was restored to normal. FERG changed abruptly before and after the hypertention.Conclusion Glaucoma may ef fect the retinal and choroidal circulation, and cause the changes of FVEP and FERG .%目的 研究青光眼对视网膜脉络膜血液循环的影响。方法 选24月龄、体重3.5~4kg的先天性青光眼大耳白兔5只(7只眼),选10只同龄大耳白兔作为对照组。另选10只2月龄、体重2kg大耳白兔前房内灌注生理盐水制成急性高眼压模型。对三组兔进行眼底照像、闪光视诱发电位(FVEP)检查,观察视网膜脉络膜血管形态和FVEP的变化。对人工急性高眼压组还进行了闪光视

  18. Modelling the impact of blood flow on the temperature distribution in the human eye and the orbit: fixed heat transfer coefficients versus the Pennes bioheat model versus discrete blood vessels

    International Nuclear Information System (INIS)

    Prediction of the temperature distribution in the eye depends on how the impact of the blood flow is taken into account. Three methods will be compared: a simplified eye anatomy that applies a single heat transfer coefficient to describe all heat transport mechanisms between the sclera and the body core, a detailed eye anatomy in which the blood flow is accounted for either by the bioheat approach, or by including the discrete vasculature in the eye and the orbit. The comparison is done both for rabbit and human anatomies, normo-thermally and when exposed to homogeneous power densities. The first simplified model predicts much higher temperatures than the latter two. It was shown that the eye is very hard to heat when taking physiological perfusion correctly into account. It was concluded that the heat transfer coefficient describing the heat transport from the sclera to the body core reported in the literature for the first simplified model is too low. The bioheat approach is appropriate for a first-order approximation of the temperature distribution in the eye when exposed to a homogeneous power density, but the discrete vasculature down to 0.2 mm in diameter needs to be taken into account when the heterogeneity of the temperature distribution at a mm scale is of interest

  19. Biological and mechanical evaluation of the small-diameter tissue-engineered blood vessels matrix%小口径组织工程血管基质材料的生物学和力学评价

    Institute of Scientific and Technical Information of China (English)

    谭菊; 曾文; 周静婷; 李刚; 张晓彦; 朱楚洪

    2014-01-01

    Objective To develop a small-diameter tissue-engineered blood vessels which possesses normal blood vessels physiological structure, good biocompatibility, and mechanical properties. And it was evaluated by mechanical and biological of national standard of medi-cal transfusion material. Methods The bio-derived material were regarded as the ground substance, and it was evaluated by mechanical and biological of national standard after composite modification. Results The axial and radial tensile stress of the blood vessel was 23. 14 N and 36. 79 N respectively, and it was greater than the standard 7. 5N. The tensile rate of the axial and radial was 95. 19% and 80. 24% respec-tively, which were higher than the standard value 20%. The suture strength of the blood vessel was 13. 71 N, which was conform to the me-chanical requirement. Mainly used blood vessels or its extracts to detect the pH of the blood vessels is in the scope of control deionized water pH (7. 5 ± 1. 5);the hemolysis rate was 1. 3972% which was less than 5%;the whole blood coagulation time was 50% longer than the con-trol level, and there was no stimulation after intradermal injection. Conclusion With bio-derived material as the ground substance and com-positely modified, this kind od blood vessels is conform to the mechanical and biological of national standard, and it has the potential of clini-cal application which could play an important role in the replacement therapy of small-diameter vascular xenografts.%目的:研制一种具备正常血管的生理结构和良好的生物相容性,而且具有血管力学特性的小口径组织工程血管基质材料,并按医用输血材料的力学及生物学国家标准评价。方法以去细胞生物衍生材料作为基质,按照国家标准对其进行力学和生物学评价。结果血管的轴向、径向拉伸应力分别为23.14 N和36.79 N,均大于标准规定的7.5 N;拉伸率分别为95.19%和80.24%,大于标准规定的20%

  20. An automated vessel segmentation of retinal images using multiscale vesselness

    International Nuclear Information System (INIS)

    The ocular fundus image can provide information on pathological changes caused by local ocular diseases and early signs of certain systemic diseases, such as diabetes and hypertension. Automated analysis and interpretation of fundus images has become a necessary and important diagnostic procedure in ophthalmology. The extraction of blood vessels from retinal images is an important and challenging task in medical analysis and diagnosis. In this paper, we introduce an implementation of the anisotropic diffusion which allows reducing the noise and better preserving small structures like vessels in 2D images. A vessel detection filter, based on a multi-scale vesselness function, is then applied to enhance vascular structures.

  1. Correlation analysis between bone density measured by quantitative CT and blood sugar level of aged patients with non-insulin-dependent diabetes mellitus

    International Nuclear Information System (INIS)

    Objective: To approach the correlation between the bone density measured by quantitative CT and the blood sugar level of the aged patients with non-insulin-dependent diabetes mellitus, and observe the effects of the blood sugar level on the bone density. Methods: The lumbar bone densities and the blood sugar levels of 160 aged patients with non-insulin-dependent diabetes mellitus (hyperglycemia group 80 cases, euglycemia group 80 cases ) and the healthy aged people (80 cases) were detected by quantitative CT and serum biochemical detection; the correlation between the blood sugar level and the bone density and the osteoporosis occurrence status of aged people in various groups were analyzed. Results: The bone density in the non-insulin-dependent diabetes and hyperglycemia group was lower than those in normal (control) group and non-insulin-dependent diabetes and euglycemia group (P<0.05); the morbility of osteoporosis in the non-insulin-dependent diabetes and hyperglycemia group was higher than those in normal (control) group and non-insulin-dependent diabetes and euglycemia group (P<0.05); negative correlation was found between the bone density and the blood sugar level (aged male group: r=-0.7382, P=0.0013; aged female group: r=-0.8343, P=0.0007). Conclusion: The blood sugar level affects the bone density of the aged patients with non-insulin-dependent diabetes mellitus; the higher the blood sugar level, the lower the bone density. The non-insulin-dependent diabetes aged patients with hyperglycemia have the liability of osteoporosis. (authors)

  2. Expansion of endothelial surface by an increase of vessel diameter during tumor angiogenesis in experimental hepatocellular and pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Eduard Ryschich; Eduard Schmidt; Sasa-Marcel Maksan; Ernst Klar; Jan Schmidt

    2004-01-01

    AIM: A low vessel density is a common feature of malignant tumors. We suggested that the expansion of vessel diameter might reconstitute the oxygen and nutritient's supply in this situation. The aim of the present study was to compare the number and diameter of blood vessels in pancreatic and liver carcinoma with normal tissue.METHODS: Tumor induction of pancreatic (DSL6A) or hepatocellular (Morris-hepatoma) carcinoma was performed in male Lewis (pancreatic cancer) and ACI (hepatoma) rats by an orthotopic inoculation of solid tumor fragments (pancreatic cancer) or tumor cells (hepatoma). Six weeks (pancreatic cancer) or 12 d (hepatoma) after tumor implantation, the tumor microvasculature as well as normal pancreatic or liver blood vessels were investigated by intravital microscopy. The number of perfused blood vessels in tumor and healthy tissue was assessed by computer-assisted image analysis.RESULTS: The vessel density in healthy pancreas (565±89n/mm2) was significantly higher compared to pancreatic cancer (116±36 n/mm2) (P<0.001). Healthy liver showed also a significantly higher vessel density (689±36 n/mm2) compared to liver carcinoma (286±32 n/mm2) (P<0.01). The comparison of diameter frequency showed a significant increase of vessel diameter in both malignant tumors compared to normal tissue (P<0.05).CONCLUSION: The expansion of endothelial cells during tumor angiogenesis is accompanied to a large extent by an increase of vessel diameter rather than by formation of new blood vessels. This may be a possible adaptive mechanism by which experimental pancreatic and hepatocellular cancers expand their endothelial diffusion surface of endothelium to compensate for inadequate neoangiogenesis.

  3. Study on the relationship of blood vessel parameters between high-normal blood pressure pilots and optimal blood pressure pilots%正常高值血压与理想血压飞行员血管指标的意义

    Institute of Scientific and Technical Information of China (English)

    唐爽; 王新宴; 许波; 黄翠莹; 臧春梅; 文腾; 宋珍珍; 王建昌

    2015-01-01

    Objective To investigate the relationship of blood vessel parameters between high-normal blood pressure pilots and optimal blood pressure pilots.Methods According to their blood pressure level, 210 pilots were divided into two groups, namely, optimal blood pressure controls(n=111), high-normal blood pressure pilots(n=99). CASP and AIxHR75 were obtained by SphygmoCor device while baPWV and ABI were detected by Omron device.Results ①baPWV, CASP and AIxHR75 were higher in high-normal blood pressure group than those in optimal blood pressures group on statistical level(P0.05).baPWV增快的比例为7.4%.②CASP分布范围在80~120 mmHg,P50为100 mmHg,P95为112 mmHg.③中心动脉血压与外周血压差值分布范围在7~31 mmHg,P50为18 mmHg,P95为24 mmHg;基本呈正态分布.结论 正常高值血压与理想血压人群的血管指标差异有统计学意义,但其与临床意义是否对等尚需进一步大样本的研究;CASP应作为评估高血压病的诊断与治疗的指标之一.

  4. Cell-free cryopreserved arterial allografts from multiorgan donors: a new strategy to fabricate artificial blood vessels suited for peripheral vascular surgery

    OpenAIRE

    Papadopulos, Francesca Marzia

    2012-01-01

    Critical lower limb ischemia is a severe disease. A common approach is infrainguinal bypass. Synthetic vascular prosthesis, are good conduits in high-flow low-resistance conditions but have difficulty in their performance as small diameter vessel grafts. A new approach is the use of native decellularized vascular tissues. Cell-free vessels are expected to have improved biocompatibility when compared to synthetic and are optimal natural 3D matrix templates for driving stem cell growth and tiss...

  5. Research on the Effect of Two Methods of Pressing Blood Vessel after Withdrawing the Needle%静脉输液拔针后两种不同按压方法比较

    Institute of Scientific and Technical Information of China (English)

    李琼; 王小平

    2014-01-01

    目的通过比较两种不同的按压方式来探讨静脉输液拔针后最佳方法,以便最大限度地减少出血及皮下瘀血,减轻患者痛苦,保护静脉血管。方法采用自身前后对照,对117例患者分别用4指按压法和握手式4指按压法进行静脉输液拔针后按压效果的观察,评价皮肤出血、皮下瘀血的发生情况。结果4指按压法与握手式4指按压法比较,出血发生率分别为7.98豫,0.85豫;瘀血发生率分别为7.12豫和0.85豫,其差异具有统计学意义(<0.01),患者更易接受握手式4指按压法。结论静脉输液拔针后使用握手式4指按压法比4指按压法能更有效地减少皮肤出血及皮下瘀血的发生,且患者乐于接受。%Objective To explore which method is more ef ective and easily accepted by patients through contrasting the method of pressing blood vessel with four fingers and the method of pressing blood vessel with four fingers holding the hand.To minimize subcutaneous blood stasis and bleeding, relieve pain, protect their veins. Methods 117cases were observed by serf-control study after withdrawing the needle.The occurrence of bleeding and petechia was evaluated.Results In the method of pressing blood vessel with four fingers and the method of pressing blood vessel with four fingers holding the hand.the occurrence rates of bleeding were 7.98%and 0.85%,and the occurrence rates of petechia were 7.12% and 0.85% respectively.There was a significant dif erence between the occurrences of bleeding and petechial ( <0.01).The patients preferred to the method of pressing blood vessel with four fingers holding the hand. Conclusion Adopting the method of pressing blood vessel with four fingers after withdrawing the needle could reduce the occurrence of bleeding and petechia more ef ectively and is bet er accepted by patients.

  6. What Causes High Blood Pressure?

    Science.gov (United States)

    ... whether imbalances in this system cause high blood pressure. Blood Vessel Structure and Function Changes in the structure ... can affect blood pressure. Genetic Causes of High Blood Pressure Much of the understanding of the body systems ...

  7. What Is High Blood Pressure?

    Science.gov (United States)

    ... also known as blood vessels and capillaries. The pressure --- blood pressure --- is the result of two forces. The ... was last reviewed on 08/04/2014. High Blood Pressure • Home • About High Blood Pressure (HBP) Introduction What ...

  8. Research on the effect of the different method of pressing blood vessel in intravenous injection after withdrawing the needle%静脉输液拔针后不同按压方法的效果观察

    Institute of Scientific and Technical Information of China (English)

    王艳杰; 姬萍

    2008-01-01

    Objective To explore which method is more effective and easily accepted by patients through contrasting the method of pressing blood vessel with four fingers and the meihod of pressing blood vessel with four fingers holding the hand.Methods In this study,to learn which method is better accepted by patients,194 cases were observed by seff-control stuay after withdrawing the needle.The Occurrence of bleeding and petechia Was evaluated.Results In the method of pressing blood vessel with four fingers and the method of pressing blood vessel with four fingers holding the hand,the occurrence rates of bleeding were 10.3 1%and 0.52%.and tlle occurrence rates of petechia were 9.28%and 0.52%,respectively.There wag a significant differenee between the occurrences of bleeding and petechia(P<0.01).The patients preferred to the method of pressing blood vessel with four fingers holding the hand.Conclusions Adopting the method of pressing blood vessel with four fingers after withdrawing the needle could reduce the occurrence of bleeding and petechia more effectively and is better accepted by patients.%目的 比较4指按压法和握式4指按压法的止血效果,探讨静脉输液拔针后最佳的按压止血方法 和病人容易接受的方法 .方法 采用自身对照法,对194例病人分别用4指按压法和握式4指按压法进行静脉输液拔针后按压效果的观察,评价皮肤出血、皮下淤血的发生情况,了解病人更容易接受哪一种按压方法 .结果 4指按压法与握式4指按压法比较,出血发生率分别为10.31%和0.52%,淤血发生率分别为9.28%和0.52%,均有统计学意义(P<0.01).病人更喜欢握式4指按压法.结论 静脉输液拔针后使用握式4指按压法能更效地减少皮血出血及皮下淤血的发生皮情况,且病人乐于接受.

  9. Microscopical and elemental FESEM and Phenom ProX-SEM-EDS analysis of osteocyte- and blood vessel-like microstructures obtained from fossil vertebrates of the Eocene Messel Pit, Germany.

    Science.gov (United States)

    Cadena, Edwin

    2016-01-01

    The Eocene (∾48 Ma) Messel Pit in Germany is a UNESCO World Heritage Site because of its exceptionally preserved fossils, including vertebrates, invertebrates, and plants. Messel fossil vertebrates are typically characterized by their articulated state, and in some cases the skin, hair, feathers, scales and stomach contents are also preserved. Despite the exceptional macroscopic preservation of Messel fossil vertebrates, the microstructural aspect of these fossils has been poorly explored. In particular, soft tissue structures such as hair or feathers have not been chemically analyzed, nor have bone microstructures. I report here the preservation and recovery of osteocyte-like and blood vessel-like microstructures from the bone of Messel Pit specimens, including the turtles Allaeochelys crassesculpta and Neochelys franzeni, the crocodile Diplocynodon darwini, and the pangolin Eomanis krebsi. I used a Field Emission Scanning Electron Microscope (FESEM) and a Phenom ProX desktop scanning electron microscope (LOT-QuantumDesign) equipped with a thermionic CeB6 source and a high sensitivity multi-mode backscatter electron (BSE) for microscopical and elemental characterization of these bone microstructures. Osteocyte-like and blood vessel-like microstructures are constituted by a thin layer (∾50 nm thickness), external and internal mottled texture with slightly marked striations. Circular to linear marks are common on the external surface of the osteocyte-like microstructures and are interpreted as microbial troughs. Iron (Fe) is the most abundant element found in the osteocyte-like and blood vessel-like microstructures, but not in the bone matrix or collagen fibril-like microstructures. The occurrence of well-preserved soft-tissue elements (at least their physical form) establishes a promising background for future studies on preservation of biomolecules (proteins or DNA) in Messel Pit fossils. PMID:26819855

  10. Development of a dynamic in vitro model of a stented blood vessel to evaluate the effects of stent strut material selection and surface coating on smooth muscle cell response

    Science.gov (United States)

    Winn, Bradley Huegh

    Cardiovascular disease is the leading cause of mortality in The United States and Europe, accounting for approximately half of all deaths. The most common form of cardiovascular disease is atherosclerosis, which is characterized by the formation of fatty atheromatous plaques that can grow to occlude the vessel lumen, thus causing ischemia distal to the occlusion. This is commonly treated using balloon angioplasty, which is usually done in conjunction with the deployment of a stent. Stent deployment helps hold the vessel open following the local injury caused by balloon inflation and prevents elastic recoil and subsequent negative remodeling. Stenting has been shown to significantly reduce restenosis rates from approximately 20-50% without a stent to about 10-30% with stent deployment. However, restenosis still remains the main cause of long-term stent failure. In basic terms, a balloon angioplasty procedure is a forceful displacement of an atherosclerotic lesion serving to widen the vessel lumen to increase blood flow. This procedure causes stretching of the vessel wall, tears in the atherosclerotic plaques, and general damage to the vessel in turn signaling a complex cascade of thrombosis, inflammation, intimal thickening, and vascular remodeling. Stent deployment also further complicates the immunological response by triggering a foreign body response from the implantation of a biomaterial into the body. When performing an angioplasty procedure, particularly in conjunction with stent deployment, a certain degree of vascular injury is inevitable. However, the initial injury can be further complicated by the body's local reaction to the implanted biomaterial, the severity of which can ultimately dictate the degree of restenosis and subsequently affect procedural success. The proliferative response of VSMCs to the various afore mentioned stimuli results in the formation of often copious amounts of neointimal tissue, generally known as intimal hyperplasia. The

  11. 血管内皮生长因子和雌二醇促进血管内皮祖细胞分化生成血管的对比研究%Comparative study of vascular endothelial growth factor and estradiol in promoting endothelial progenitor cells differentiation and generation blood vessels

    Institute of Scientific and Technical Information of China (English)

    董勇; 李文志; 辛毅; 孙智

    2013-01-01

    Objective To compare the ability of vascular endothelial growth factor (VEGF) and estradiol in promoting endothelial progenitor cells differentiation and generation blood vessels under common doses. Methods To isolate and culture human peripheral blood EPCs first, then to mixe with the matrigel and transplante to the lower abdomens of nine nude mice.to divide the nine nude mice into three groups according to a random grouping, to inject VEGF.estradiol and saline at a regular time,to observe and record the growing status of vascular tissue regularly.to draw the vascular tissue after six weeks, to observe the organizational structure by HE staining, then contrast with the groups. Results The vascular tissue volume groups injected of drugs have significant difference with the groups injected of saline.they have bigger volume to contrast the groups injected of saline, but he vascular tissue volume between the groups injected of drugs is no significant difference. By drawning HE staining, the vascular tissues have proliferational mussy blood vessels.The vascular density of the groups injected of drugs is significantly greater than the groups injected of saline, but he vascular density between the groups injected of drugs is small. Conclusion VEGF and estradiol can promote EPCs differentiation and generation blood vessels.their respective promoting EPCs differentiation and generation blood vessels potency is no significant difference under common doses.%目的:对比研究常规剂量下血管内皮生长因子(VEGF)和雌二醇对血管内皮祖细胞(EPCs)分化生成血管的促进作用.方法:分离培养人外周血EPCs,与基质胶混匀后注射到9只裸鼠双侧下腹部,另设2只注射等体积培养液与基质胶的混合液.将9只注射细胞的裸鼠随机分为3组,每组分别定期局部注射VEGF、雌二醇,生理盐水,定期观察记录血管组织块的生长状况.移植6周后取材,测量计算血管组织块的体积、HE染色观察血管

  12. A software application for comparing large numbers of high resolution MALDI-FTICR MS spectra demonstrated by searching candidate biomarkers for glioma blood vessel formation

    Directory of Open Access Journals (Sweden)

    Smitt Peter

    2008-03-01

    Full Text Available Abstract Background A Java™ application is presented, which compares large numbers (n > 100 of raw FTICR mass spectra from patients and controls. Two peptide profile matrices can be produced simultaneously, one with occurrences of peptide masses in samples and another with the intensity of common peak masses in all the measured samples, using the peak- and background intensities of the raw data. In latter way, more significantly differentially expressed peptides are found between groups than just using the presence or absence in samples of common peak masses. The software application is tested by searching angiogenesis related proteins in glioma by comparing laser capture micro dissected- and enzymatic by trypsin digested tissue sections. Results By hierarchical clustering of the presence-absence matrix, it appears that proteins, such as hemoglobin alpha and delta subunit, fibrinogen beta and gamma chain precursor, tubulin specific chaperone A, epidermal fatty acid binding protein, neutrophil gelatinase-associated lipocalin precursor, peptidyl tRNA hydrolase 2 mitochondrial precursor, placenta specific growth hormone, and zinc finger CCHC domain containing protein 13 are significantly different expressed in glioma vessels. The up-regulated proteins in the glioma vessels with respect to the normal vessels determined by the Wilcoxon-Mann-Whitney test on the intensity matrix are vimentin, glial fibrillary acidic protein, serum albumin precursor, annexin A5, alpha cardiac and beta actin, type I cytoskeletal 10 keratin, calcium binding protein p22, and desmin. Peptide masses of calcium binding protein p22, Cdc42 effector protein 3, fibronectin precursor, and myosin-9 are exclusively present in glioma vessels. Some peptide fragments of non-muscular myosin-9 at the C-terminus are strongly up-regulated in the glioma vessels with respect to the normal vessels. Conclusion The less rigorous than in general used commercial propriety software de

  13. Reduction of low-density lipoprotein cholesterol, plasma viscosity, and whole blood viscosity by the application of pulsed corona discharges and filtration

    Science.gov (United States)

    Jung, Jin M.; Fridman, Alexander; Cho, Daniel J.; Cho, Young I.

    2013-03-01

    The present study investigated the feasibility of applying pulsed corona discharges to blood plasma to reduce the viscosity of blood plasma and whole blood. Blood plasma was separated from blood cells, treated with corona discharges, and filtered before it was re-mixed with blood cells. Plasma viscosity (PV), whole blood viscosity (WBV), and low-density lipoprotein (LDL)-c concentration were measured before and after the corona treatment and filtration. Both PV and WBV increased in the case of the corona treatment only, whereas both of them decreased in the case of the corona treatment plus filtration. In particular, the LDL-c decreased in the case of the corona treatment plus filtration by 31.5% from the baseline value. The effect of the corona treatment on the reduction of the WBV was significant at low shear rates, but not at high shear rates, suggesting that the precipitation of the molecules in blood plasma by the corona treatment and subsequent removal may suppress the aggregation of erythrocytes and improve rheological properties of blood.

  14. Reduction of low-density lipoprotein cholesterol, plasma viscosity, and whole blood viscosity by the application of pulsed corona discharges and filtration.

    Science.gov (United States)

    Jung, Jin M; Fridman, Alexander; Cho, Daniel J; Cho, Young I

    2013-03-01

    The present study investigated the feasibility of applying pulsed corona discharges to blood plasma to reduce the viscosity of blood plasma and whole blood. Blood plasma was separated from blood cells, treated with corona discharges, and filtered before it was re-mixed with blood cells. Plasma viscosity (PV), whole blood viscosity (WBV), and low-density lipoprotein (LDL)-c concentration were measured before and after the corona treatment and filtration. Both PV and WBV increased in the case of the corona treatment only, whereas both of them decreased in the case of the corona treatment plus filtration. In particular, the LDL-c decreased in the case of the corona treatment plus filtration by 31.5% from the baseline value. The effect of the corona treatment on the reduction of the WBV was significant at low shear rates, but not at high shear rates, suggesting that the precipitation of the molecules in blood plasma by the corona treatment and subsequent removal may suppress the aggregation of erythrocytes and improve rheological properties of blood.

  15. Transport of jundiá Rhamdia quelen juveniles at different loading densities: water quality and blood parameters

    Directory of Open Access Journals (Sweden)

    Paulo César Falanghe Carneiro

    2009-06-01

    Full Text Available Fish transportation is a common practice on fish farms and is considered to be a stressor that could negatively affect fish health. The objective of this study was to evaluate several physiological responses of stress in jundiá caused by transport at different loading densities. Jundiá juveniles were placed in plastic bags on a mechanical transport simulator for four hours at four different loading densities (75, 150, 250 and 350 g L-1 and then transferred to sixteen 80-L plastic boxes for 96 hours after transport. Water samples were collected before and after transport to measure dissolved oxygen, temperature, pH and ammonia levels. Blood samples were taken at departure and arrival, as well as at 24 and 96 hours after transport to monitor cortisol, glucose, ammonia, chloride and hematocrit levels. Water ammonia levels were found to increase gradually as loading densities increased. Plasma ammonia was higher after transport in fish from all treatments. Compared to initial values, substantial increases in plasma cortisol and ammonia levels were detected mainly in those fish submitted to the highest loading density. Blood glucose appeared to be positively influenced by the increase of transport densities. No statistical differences were observed in any of the other blood parameters. The costs in fish culture, as in other animal production systems, must be minimized and fish producers depend on optimal techniques to ensure better profit. Therefore, based on fish survival and the physiological indicators determined in the present study, especially during recovery, the best density at which to transport jundiá in plastic bags for four hours is about 350 g/L.O transporte de peixes é uma prática comum em piscicultura e considerado como um agente estressor que causa efeitos negativos na saúde do peixe. O objetivo deste estudo foi avaliar algumas respostas fisiológicas de estresse no jundiá causadas pelo transporte em densidades diferentes

  16. Blood-Borne Lipopolysaccharide Is Rapidly Eliminated by Liver Sinusoidal Endothelial Cells via High-Density Lipoprotein.

    Science.gov (United States)

    Yao, Zhili; Mates, Jessica M; Cheplowitz, Alana M; Hammer, Lindsay P; Maiseyeu, Andrei; Phillips, Gary S; Wewers, Mark D; Rajaram, Murugesan V S; Robinson, John M; Anderson, Clark L; Ganesan, Latha P

    2016-09-15

    During Gram-negative bacterial infections, excessive LPS induces inflammation and sepsis via action on immune cells. However, the bulk of LPS can be cleared from circulation by the liver. Liver clearance is thought to be a slow process mediated exclusively by phagocytic resident macrophages, Kupffer cells (KC). However, we discovered that LPS disappears rapidly from the circulation, with a half-life of 2-4 min in mice, and liver eliminates about three quarters of LPS from blood circulation. Using microscopic techniques, we found that ∼75% of fluor-tagged LPS in liver became associated with liver sinusoidal endothelial cells (LSEC) and only ∼25% with KC. Notably, the ratio of LSEC-KC-associated LPS remained unchanged 45 min after infusion, indicating that LSEC independently processes the LPS. Most interestingly, results of kinetic analysis of LPS bioactivity, using modified limulus amebocyte lysate assay, suggest that recombinant factor C, an LPS binding protein, competitively inhibits high-density lipoprotein (HDL)-mediated LPS association with LSEC early in the process. Supporting the previous notion, 3 min postinfusion, 75% of infused fluorescently tagged LPS-HDL complex associates with LSEC, suggesting that HDL facilitates LPS clearance. These results lead us to propose a new paradigm of LSEC and HDL in clearing LPS with a potential to avoid inflammation during sepsis. PMID:27534554

  17. 多普勒血流检查评价下肢动脉旁路术流出道的价值%Doppler ultrasound assess outlets in lower extremity arterias treated by blood vessel prosthesis

    Institute of Scientific and Technical Information of China (English)

    周晗; 吴庆华; 陈忠; 罗小云; 张煜亚; 杨培

    2009-01-01

    目的 探讨多普勒血流检查中节段性压力比值对评估下肢动脉硬化闭塞症患者远端动脉流出道的应用价值,以对人工血管旁路术适应证的选择提供参考.方法 回顾性分析北京安贞医院血管外科1998--2005年收治的166例下肢动脉硬化闭塞症行人工血管旁路术患者的资料,分析流出道节段性压力比值差值等与人工血管通畅率相关的因素,比较人工血管通畅组与阻塞组术前流出道节段性压力比值差值的差异.结果 流出道的节段性压力比值差值是影响人工血管术后通畅率危险程度最高的相关因素之一.人工血管通畅组与阻塞组流出道节段性压力比值差值分别为0.12±0.09和0.24±0.14,两组间比较,差异有统计学意义(P=0.001).人工血管通畅组流出道的节段性压力比值差值的95%可信区间为(0,0.27).结论 多普勒血流检查是一种量化的检查方法,节段性压力比值差值的区间范围可以作为临床上评价流出道及预测手术通畅率的参考.%Objective To explore segmantal blood pressure ratio in Doppler ultrasound in the evaluation of distal outlets in lower extremity atherosclerosis ocllusion patients undergoing blood vessel prosthesis and provide references to surgical indications. Methods A review research was made on 166 lower extremity atherosclerosis ocllusion patients receiving blood vessel prosthesis therapy in Anzhen hospital in 1998--2005. We analyzed related factors including segmantal blood pressure ratio to potency rate, evaluated the difference of segmantal blood pressure ratio between groups in which the blood vessel prosthesis was patent and that it was not. Results The difference of segmantal blood pressure ratio of outlet is one of the highest risk among risk factors. The Mean ± SDs of segmantal blood pressure ratio of outlet in patent and obstructed groups were 0. 12±0. 09 and 0. 24±0. 14 respectively. The difference of segmantal blood pressure

  18. Model studies of leukocyte-endothelium-blood interactions. II. Hemodynamic impact of leukocytes adherent to the wall of post-capillary vessels.

    Science.gov (United States)

    Chapman, G B; Cokelet, G R

    1997-01-01

    Computational fluid dynamics (CFD) and large scale model experiments were used to analyze the hemodynamic impact of leukocytes adherent to the wall of post-capillary venules. Using a large scale model and, with the aid of a finite element package, solving the Navier Stokes equations for low Reynolds number flow in a cylinder past an adherent sphere, we have developed a dimensionless correlation which permits the estimation of the pressure drop across an adherent leukocyte in an in vivo vessel. This relationship is: f.Re = exp[2.877+4.630 (d/D)4] where f is the Fanning friction factor, Re is the Reynolds number and d/D is the leukocyte to vessel diameter ratio. The friction factor is proportional to the pressure drop across the leukocyte, and does not significantly increase until d/D is greater than 0.5, and then increases rapidly with increasing d/D. Computations indicate that the length of the disturbed flow region generated by an adherent leukocyte increases with decreasing vessel size. The average wall stress in the disturbed flow region remains constant, and equal to the wall stress in the undisturbed region for d/D less than approximately 0.5. For d/D greater than 0.5, the average wall stress in the disturbed flow region increases rapidly with increasing d/D. There is an even larger increase, up to five times greater than the average disturbed stress, in the peak wall stress in the disturbed flow region. This indicates that significant wall stress gradients can be generated by an adherent leukocyte in post-capillary size vessels.

  19. Optimizing 18F-FDG PET/CT imaging of vessel wall inflammation: the impact of 18F-FDG circulation time, injected dose, uptake parameters, and fasting blood glucose levels

    International Nuclear Information System (INIS)

    18F-FDG PET is increasingly used for imaging of vessel wall inflammation. However, limited data are available on the impact of methodological variables, i.e. prescan fasting glucose, FDG circulation time and injected FDG dose, and of different FDG uptake parameters, in vascular FDG PET imaging. Included in the study were 195 patients who underwent vascular FDG PET/CT of the aorta and the carotids. Arterial standardized uptake values (meanSUVmax), target-to-background ratios (meanTBRmax) and FDG blood-pool activity in the superior vena cava (SVC) and the jugular veins (JV) were quantified. Vascular FDG uptake values classified according to the tertiles of prescan fasting glucose levels, the FDG circulation time, and the injected FDG dose were compared using ANOVA. Multivariate regression analyses were performed to identify the potential impact of all variables described on the arterial and blood-pool FDG uptake. Tertile analyses revealed FDG circulation times of about 2.5 h and prescan glucose levels of less than 7.0 mmol/l, showing a favorable relationship between arterial and blood-pool FDG uptake. FDG circulation times showed negative associations with aorticmeanSUVmax values as well as SVC and JV FDG blood-pool activity, but positive correlations with aortic and carotidmeanTBRmax values. Prescan glucose levels were negatively associated with aortic and carotidmeanTBRmax and carotidmeanSUVmax values, but were positively correlated with SVC blood-pool uptake. The injected FDG dose failed to show any significant association with vascular FDG uptake. FDG circulation times and prescan blood glucose levels significantly affect FDG uptake in the aortic and carotid walls and may bias the results of image interpretation in patients undergoing vascular FDG PET/CT. The injected FDG dose was less critical. Therefore, circulation times of about 2.5 h and prescan glucose levels less than 7.0 mmol/l should be preferred in this setting. (orig.)

  20. The anatomy and clinical application of sural blood vessel combined with free skin flap%腓肠血管联合游离皮瓣的解剖及临床应用

    Institute of Scientific and Technical Information of China (English)

    葛东江; 任志勇; 魏长月; 张坤; 张维彬; 王辉

    2014-01-01

    目的:探讨腓肠血管的解剖学特性及其联合游离皮瓣修复小腿大段组织缺损的临床疗效。方法实验研究:10具新鲜成人尸体标本,随机选择4具,每具结扎一侧肢体腓肠内侧动脉,另4具结扎腓肠外侧动脉,对侧肢体不结扎作为对照,对标本进行血管造影,观察结扎一侧腓肠内或腓肠外动脉后,该侧腓肠肌的血液供应;另外2具通过解剖学及小腿铸型标本观察该侧腓肠肌的血管交通支的来源、管径及部位。临床研究:回顾性分析2006年10月至2013年9月收治的19例小腿大段组织缺损患者资料,男11例,女8例;年龄10~40岁,平均32岁。其中12例采用腓肠内侧血管、7例采用腓肠外侧血管为受区血管,同时6例取游离胸脐皮瓣移植、8例取大腿前外侧皮瓣移植、2例取侧胸皮瓣移植、3例取背阔肌皮瓣移植修复组织缺损。创面面积为5 cm×10 cm~8 cm×37 cm,切取皮瓣面积为7 cm×10 cm~10 cm×30 cm。结果实验研究发现,小腿腓肠肌的血供为多源性,以腓肠动脉供血为主;当切断一侧腓肠血管时,来自腓肠肌内、外侧头之间的交通支和来自比目鱼肌交通支的血液供应该侧腓肠肌,且交通支管径粗、分支多、位置恒定。临床研究显示19例游离皮瓣全部成活,创面愈合时间13~29 d,其中一期愈合11例,二期愈合8例。随访时间12~24个月,皮瓣能耐受一定程度摩擦,均无明显感觉障碍。供区取自体腹部或大腿中厚皮片植皮覆盖,均一期愈合。结论腓肠血管位于腓肠肌深层,位置恒定,蒂长、易分离,管径较粗,适于吻合,腓肠血管联合游离皮瓣为小腿大段组织缺损修复提供一种新的治疗方法。%Objective To study the anatomical characteristics of sural blood vessel, and to explore the clinical effect of sural blood vessel combined with free skin flap in repairing large tissue

  1. Human cord blood progenitors with high aldehyde dehydrogenase activity improve vascular density in a model of acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Creer Michael H

    2010-03-01

    Full Text Available Abstract Human stem cells from adult sources have been shown to contribute to the regeneration of muscle, liver, heart, and vasculature. The mechanisms by which this is accomplished are, however, still not well understood. We tested the engraftment and regenerative potential of human umbilical cord blood-derived ALDHhiLin-, and ALDHloLin- cells following transplantation to NOD/SCID or NOD/SCID β2m null mice with experimentally induced acute myocardial infarction. We used combined nanoparticle labeling and whole organ fluorescent imaging to detect human cells in multiple organs 48 hours post transplantation. Engraftment and regenerative effects of cell treatment were assessed four weeks post transplantation. We found that ALDHhiLin- stem cells specifically located to the site of injury 48 hours post transplantation and engrafted the infarcted heart at higher frequencies than ALDHloLin- committed progenitor cells four weeks post transplantation. We found no donor derived cardiomyocytes and few endothelial cells of donor origin. Cell treatment was not associated with any detectable functional improvement at the four week endpoint. There was, however, a significant increase in vascular density in the central infarct zone of ALDHhiLin- cell-treated mice, as compared to PBS and ALDHloLin- cell-treated mice. Conclusions Our data indicate that adult human stem cells do not become a significant part of the regenerating tissue, but rapidly home to and persist only temporarily at the site of hypoxic injury to exert trophic effects on tissue repair thereby enhancing vascular recovery.

  2. 无创中心动脉压检测在高血压患者血压管理及血管功能评估中的应用%The Application of Noninvasive Central Blood Pressure Detection in Blood Pressure Management and Vessel Function Assessment of Hypertension

    Institute of Scientific and Technical Information of China (English)

    李明珠; 刘玥; 李敏; 江华

    2015-01-01

    Objectives To explore the significance of noninvasive central blood pressure detection in blood pressure management and vessel function assessment of hypertension.MethodsA total of 348 subjects were recruited in the study and A-pulse CASP software were derived to measure the parameters of CASP and vessel function. The recruited subjects were divided into different groups for analysis according to age and disease.Results①CASP in hypertension group were both higher than those in normal group, while RAI and PRT lower.②Hypertensive patients of which brachial blood pressure were controlled have lower CASP and RAI than those above the level.③ Hypertensive patients whose brachial blood pressure were controled have significantly higher CASP than normal subjects.Conclusions Central blood pressure is more reflective of actural blood pressure and vessel function. Enhanced control of CASP in hypertensive patients contributes to improving vessel compliance.%目的 探索无创中心动脉压检测对血压管理及评估血管功能的意义.方法 入选对象348例.采用BPro?动脉脉搏波采集设备结合A-PULSE CASP?中心动脉压应用软件检测,按年龄、疾病等分组统计,探讨无创中心动脉压检测在血压管理及评估血管功能方面的临床意义.结果①高血压组中心动脉收缩压(Central Aortic Systolic Pressure,CASP)显著高于正常组;反射波增强指数(Radial Augmentation Index,RAI)、收缩期巅峰与动脉反射波时差(Peak Relative Time, PRT)小于正常组.②血压控制达标组CASP、RAI均小于未达标组.③血压控制达标组CASP较正常组偏高.结论 CASP能更准确地反映实际血压,控制中心动脉压有助于改善血管顺应性.

  3. 尿道下裂包皮血管分布及其与术后近期并发症的相关性研究%Blood vessel distribution of foreskin in children with hypospadias and its correlation with postoperative early complications

    Institute of Scientific and Technical Information of China (English)

    赵彰; 孙宁; 张潍平; 白继武; 田军; 李明磊; 宋宏程; 李宁

    2012-01-01

    目的 通过对尿道下裂患儿包皮及皮瓣血管蒂的血管分布进行研究,评估并重新认识成形尿道材料的血运情况.术后对患儿随访,了解近期并发症的发生情况,探讨包皮血管分布与近期并发症的相关性,评估手术效果.方法 利用冷光源透照包皮法记录血管的分布及数量并进行归纳、分析、总结.术后对行Duckett或Duckett+ Duplay手术治疗的患儿进行随访.结果 包皮浅筋膜深层血管分布类型:①1支主导血管,占42.4%;②2支主导血管,占34.7%;③3支主导血管,占13.6%;④多支主导血管(主导血管>3支),占2.5%;⑤无明确主导血管,占6.8%.在有主导血管的病例中,主导血管的数目与尿道瘘及尿道狭窄的发生率无明确关系.结论 尿道下裂患儿包皮浅筋膜深层血管分布可分为五个类型.浅筋膜深层血管分布类型与尿道下裂的严重程度无明确对应关系.包皮血管分布对Duckett整体手术效果影响很小.%Objective To study the blood vessels distribution of foreskin in children with hypospadias and vesselpedicle, aiming to evaluate and recognize blood supply after application of urethra reconstruction materials. Follow up study was conducted after surgery and early complications were investigated to evaluate the correlation between blood vessel distribution of foreskin and early complications, as well as the therapeutic efficacy. Methods Duckett and Duckett + Duplay procedures were performed for the children with hypospadias. The cold lighting transmission techniques was utilized to record and evaluate the distribution of blood vessels in foreskins, and followed by summarization and analysis. The follow up was conducted for patients. Results Various blood vessels distribution could be found in superficial fascia in foreskin, in which simple main branch blood vessel type was 42.4 percent, double main branches type was 34.7 percent, three main branches types in them was 13

  4. Medications for High Blood Pressure

    Science.gov (United States)

    ... dangerous as elevations of both systolic and diastolic pressure. Blood pressure is elevated for two main reasons: too ... and Angiotensin II receptor blockers (ARBs), reduce blood pressure by relaxing blood vessels Beta blockers, which also cause the heart ...

  5. Application of blood vessel controlling skill in pancreatoduodenectomy%血管控制技术在胰十二指肠切除手术中的应用

    Institute of Scientific and Technical Information of China (English)

    赵玉洲; 韩广森; 李智; 任莹坤; 鲁朝敏; 顾焱晖

    2011-01-01

    目的 总结血管控制技术在胰头十二指肠切除手术中的应用效果.方法 回顾分析2004年7月-2010年7月96例胰十二指肠切除的患者中37例应用血管控制技术手术的手术时间、术中出血量、淋巴结清扫个数、并发症发生率及术后住院时间与传统手术组的差异.结果 两组的手术时间、术中出血量、淋巴结清扫个数和术后住院时间分别为(115.2±23.6)min和(198.3±15.2)rain,(206±42)ml和(637±186)ml,(6.7 4-1.8)个和(6.3±2.2)个,(13.9 4-1.7)h和(17.1±2)d,并发症发生率分别为:10.8%,28.8%.显示应用血管控制技术组的手术时间明显缩短,出血量明显减少,并发症发生率明显降低,差异均有统计学意义P<0.05.而淋巴结清扫个数及住院时间与传统手术组相一致.结论 胰十二指肠切除手术应用血管控制技术手术切除可明显缩短手术时间,减少出血量,降低并发症发生率.%Objective To evaluate the effect of blood vessel controlling skill in pancreatoduodenectomy. Methods Clinical data on 96 patients with pancreatoduodenectomy were collected prospectively. 59 patients underwent traditional method and 37 patients underwent amending procedure under the blood vessel controlling skill. In the two groups, the comparation of the mean operative time, the blood loss, the number of lymph nodes dissection and the mean time of hospital stay was done. Results In two group, the mean operative time, the blood loss, the number of lymph nodes dissection and the mean time of hospital stay were( 115.2 ± 23.6 )minutes and (198.3 ± 15.2)minutes, (206 ± 42 )ml and ( 637 ± 186 ) ml, (6. 7 ± 1.8 ) and ( 6. 3 ± 2. 2 ), ( 13.9 ± 1.7 ) h days and ( 17. 1 ± 2 ) days. The complication incidence is 10. 8% ,28.8% separately. There are statistically significant difference of the mean operative time, the blood loss,and complication incidence. Conclusions Amending pancreatoduodenectomy under the blood vessel controlling skill can

  6. Biomechanical properties of relevant blood vessels in the heterogeneic heart transplantation from swine to human%猪→人异种心脏移植中相关血管的生物力学特性

    Institute of Scientific and Technical Information of China (English)

    张一飞; 余明华; 唐杰; 黄铁柱

    2006-01-01

    BACKGROUND: The source of conspecific heart transplantation organ is very limited and deficiency becomes more and more obvious.OBJECTIVE: To observe the mechanical properties of ascending aorta at one-dimensional loading between healthy persons and swine of different months, so as to provide necessary biomechanical experimental basis for anastomosing blood vessel in heterogeneic heart transplantation from swine to human.DESIGN: Open design SETTING: Staff Room of Anatomy, Yunyang Medical College MATERIALS: This experiment was carried out at the Laboratory of Biomechanics, Yunyang Medical College from April 2002 to July 2003.Ascending aortas of human were obtained from the 6 adult male corpses without cardiovascular diseases, aged 18 to 30 years, who died for accident and donated by Yunyang Medical College. Totally 42 conspecific swine of 1 month old, with certification number of QN0202, were provided by Animal Experimental Center of Yunyang Medical College. They were raised with common foodstuff. The 42 swine were butchered respectively at 1,2,3,4,5,6 and 7 months, 6 swine once. After anatomical isolation and in situ measurement of respective in vivo length, ascending aorta from aorta valve ring base plane to initiation part of innominate artery was taken out (Artherosclerosis was not presented in all the samples) and divided into five equal segments, and the second and fourth segments were used for mechanical test of one-dimensional loading.METHODS: Six adult male corpses and ascending aorta of 42 swine of 1 to 7 months were performed mechanical test of one-dimensional loading.All the blood segments were pre-treated ten times with the same strain rate at room temperature 32 ℃(loading range from 0 to 0.5 N). Hysteresis disappeared after blood vessel was given periodic permanent loading and unloading, and repeated force-deformed data were obtained. Blood vessel was given loading and unloading once with the same loading range and strain rate. The recorded force

  7. 联合止痛消炎膏外敷治疗血管周围皮肤肿胀疗效观察%Combination of analgesic antiphlogistic cream topical treatment curative effect observation of blood vessels surrounding skin swelling

    Institute of Scientific and Technical Information of China (English)

    张华; 张业光

    2013-01-01

    Objective To observe the combination of anti-inflammatory plaster topical treatment of fistula puncture failure within blood extravasation around blood vessels caused by swelling the clinical effect of skin. Methods 34 patients blood extravasation of xylene-induced ear edema blood vessels surrounding skin of patients, randomly divided into observation group and control group, each group of 17 cases, observation group with potato chips+xi liao completed + analgesic antiphlogistic cream topical side limb injury in fistula. In the control group with cold + 50%magnesium sulfate wet-apply internal fistula side body. Results The observation group 8 cases cured, accounted for 47%, 6 cases had marked effect, 35%, 3 cases(18%). And Control group recovered in 3 cases, accounting for 18%, 5 cases had marked effect, 29%, 7 cases (41%), and ineffective in 2 cases, accounting for 12%. Observation group of patients satisfaction 95%, control group patients' satisfaction was 80%. Observation group significantly reduce pain, swelling, eliminate time significantly shortened, subcutaneous ecchymosis dissipate quickly, no internal fistula embolism. Conclusion The combined application of analgesic antiphlogistic cream, fistula puncture failure blood extravasation to surrounding skin swelling blood vessels more effective.%目的:观察联合使用消炎止痛膏外敷治疗内瘘穿刺失败血液外渗致血管周围皮肤肿胀的临床效果。方法将34例血液外渗致血管周围皮肤肿胀的患者随机分为观察组和对照组,每组17例,观察组用土豆片+喜辽妥+止痛消炎膏外敷损伤内瘘侧肢体;对照组用冷敷+50%硫酸镁湿敷内瘘侧肢体。观察2组疗效及患者满意度情况。结果观察组痊愈8例,占47%,显效6例,占35%,有效3例,占18%;对照组痊愈3例,占18%,显效5例,占29%,有效7例,占41%,无效2例,占12%。观察组患者满意度为95%,对照组患者满意度为80%。观察组疼痛

  8. Evaluation on the Feasibility of Using Ultrasonic Testing of Reactor Pressure Vessel Welds for Assessing Flaw Density/Distribution per 10 CFR 50.61a, Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Edmund J.; Anderson, Michael T.

    2014-06-10

    This technical letter report provides the status of an assessment undertaken by PNNL at the request of the NRC to verify the capability of periodic ASME-required volumetric examinations of reactor vessels to characterize the density and distribution of flaws of interest for applying §50.61a on a plant-by-plant basis. The PTS rule, described in the Code of Federal Regulations, Title 10, Section 50.61 (§50.61), "Fracture Toughness Requirements for Protection against Pressurized Thermal Shock Events," establishes screening criteria to ensure that the potential for a reactor vessel to fail due to a PTS event is deemed to be acceptably low. Recently, the NRC completed a research program that concluded that the risk of through-wall cracking due to a PTS event is much lower than previously estimated. The NRC subsequently developed and promulgated an alternate PTS rule, §50.61a, that can be implemented by PWR licensees. The §50.61a rule differs from §50.61 in that it requires licensees who choose to follow this alternate method to analyze the results from periodic volumetric examinations required by the ASME Code, Section XI, Rules for Inservice Inspection (ISI) of Nuclear Power Plants.

  9. Effects of Low-Impact Dance on Blood Biochemistry, Bone Mineral Density, the Joint Range of Motion of Lower Extremities, Knee Extension Torque, and Fall in Females.

    Science.gov (United States)

    Wu, Hui Ying; Tu, Jui Hung; Hsu, Chin Hsing; Tsao, Te Hung

    2016-01-01

    The effect of low-impact dance on blood metabolites, the joint range of motion (ROM) of the lower extremities, knee extension torque, bone mass density (BMD), the number of falls, and the confidence to perform daily activities (Modified Falls Efficacy Scale [MFES]) was examined in older sedentary women (age: 59 ± 4 years) before and after a 16-week intervention. Results showed that the average score for the MFES, some parameters of blood chemistry, and joint ROM were significantly improved after low-impact intervention. In addition to improvements in blood lipids and body fat percentages, the increases shown in the parameters regarding the lower extremities may contribute to confidence in performing common daily activities in older women, although the number of falls did not significantly differ between the two groups during the 16-week period. PMID:25642949

  10. Effects of Low-Impact Dance on Blood Biochemistry, Bone Mineral Density, the Joint Range of Motion of Lower Extremities, Knee Extension Torque, and Fall in Females.

    Science.gov (United States)

    Wu, Hui Ying; Tu, Jui Hung; Hsu, Chin Hsing; Tsao, Te Hung

    2016-01-01

    The effect of low-impact dance on blood metabolites, the joint range of motion (ROM) of the lower extremities, knee extension torque, bone mass density (BMD), the number of falls, and the confidence to perform daily activities (Modified Falls Efficacy Scale [MFES]) was examined in older sedentary women (age: 59 ± 4 years) before and after a 16-week intervention. Results showed that the average score for the MFES, some parameters of blood chemistry, and joint ROM were significantly improved after low-impact intervention. In addition to improvements in blood lipids and body fat percentages, the increases shown in the parameters regarding the lower extremities may contribute to confidence in performing common daily activities in older women, although the number of falls did not significantly differ between the two groups during the 16-week period.

  11. High blood pressure and eye disease

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/000999.htm High blood pressure and eye disease To use the sharing features ... are sent to the brain. Causes High blood pressure can damage blood vessels in the retina. The higher the blood ...

  12. Assessment risk of osteoporosis in Chinese people: relationship among body mass index, serum lipid profiles, blood glucose, and bone mineral density

    Science.gov (United States)

    Cui, Rongtao; Zhou, Lin; Li, Zuohong; Li, Qing; Qi, Zhiming; Zhang, Junyong

    2016-01-01

    Objective The aim of our study was to investigate the relationship among age, sex, body mass index (BMI), serum lipid profiles, blood glucose (BG), and bone mineral density (BMD), making an assessment of the risk of osteoporosis. Materials and methods A total of 1,035 male and 3,953 female healthy volunteers (aged 41–95 years) were recruited by an open invitation. The basic information, including age, sex, height, weight, waistline, hipline, menstrual cycle, and medical history, were collected by a questionnaire survey and physical examination. Serum lipid profiles, BG, postprandial blood glucose, and glycosylated hemoglobin were obtained after 12 hours fasting. BMD in lumbar spine was measured by dual-energy X-ray absorptiometry scanning. Results The age-adjusted BMD in females was significantly lower than in males. With aging, greater differences of BMD distribution exist in elderly females than in males (P7.0 mmol/L was lower than in people with BG of ≤7.0 mmol/L (P<0.001). People with serum high-density lipoprotein cholesterol levels of ≥1.56 mmol/L had a greater prevalence of osteoporosis compared with high-density lipoprotein cholesterol ≤1.55 mmol/L. Logistic regression with odds ratios showed that no association was found among total cholesterol, triglyceride, low-density lipoprotein cholesterol, glycosylated hemoglobin, postprandial blood glucose and BMD. Conclusion The present study further confirmed that factors such as age, sex, weight, BMI, high-density lipoprotein cholesterol, and diabetes are significant predictors of osteoporosis in the Chinese people. PMID:27445467

  13. Dissolution vessel

    Energy Technology Data Exchange (ETDEWEB)

    Natsume, Tomohiro; Fujioka, Tsunaaki

    1998-05-22

    A basket for containing sheared fuel pieces of spent fuel assemblies in a dissolving vessel main body has many apertures for keeping the concentration of a dissolving liquid at the inner side and the outer side of the basket uniformly. Secured neutron absorbers such as boron stainless and hafnium are appended to one or both surfaces of the basket. Partitioning members are disposed in the basket, and the partitioning members are formed in a lattice-like shape. The partitioning members are also made of secured neutron absorbers such as boron stainless and hafnium. The inside dimension of each division (lattice distance) is determined to about 15cm. Then, it is no more necessary to add soluble neutron absorbers such as gadolinium nitrate to a dissolution solution such as nitric acid thereby enabling to reduce the amount of radioactive wastes. (I.N.)

  14. Expression of tumor necrosis factor in blood vessels and myocardium after allogenic vasotransplantation%同种异体血管移植后TNF在血管和心肌组织中的表达

    Institute of Scientific and Technical Information of China (English)

    陈晓慨; 白菡; 朱兵; 徐世安; 王练英

    2007-01-01

    目的 探讨同种异体血管移植后肿瘤坏死因子(TNF)在移植的血管和心肌组织中的表达.方法 用成年雄性新西兰大白兔做血管供者,日本大白兔做血管受者,进行颈动脉血管移植.通过新鲜植入、抗生素处理及液氮冷冻等方法对移植的血管进行处理,HE染色观察移植血管和心肌组织的形态学改变;免疫组织化学方法检测移植血管和受者心肌组织TNF表达的变化.结果 TNF表达率在液氮冷冻组低于新鲜移植组和抗生素处理组,与自体原位移植组相似.新鲜移植组TNF表达率最高,各组间比较差异有显著性(P<0.05).血管移植后,受者心肌组织的TNF的表达与移植血管的相似:新鲜移植组和抗生素处理组的TNF表达率较高,液氮冷冻组的TNF表达率较低(P<0.05).结论 同种异体血管移植能激发移植血管和心肌组织产生TNF,液氮冷冻处理可降低移植血管和受者心肌组织的TNF的产生.%[Objective] To study the variance of tumor necrosis factor (TNF) in grafted blood vessels and myoeardium.[Methods] The carotid vasotransplantation was performed with male mature Japanese albino rabbits as vascular recipients and New Zealand rabbits as vascular donors.Immunohistochemical methods were used to detect TNF expression in grafted blood vessels and myoeardium.[Results]TNF positive expression was lower in the autoorthotopie transplantation group and the liquid nitrogen frozen group than that in the fresh transplantation group and the antibiotic-treated group.And as compared with the other groups,the positive expression of TNF was the highest in the fresh transplantation group,and there was statistic significance(P<0.05).After vasotransplantation,the findings of myocardium were allogenic as vasotransplantation.TNF expression was higher in fresh transplantation group than that in the other groups.Compared with auto-orthotopie transplantation group and liquid nitrogen frozen group,there was

  15. Optimizing {sup 18}F-FDG PET/CT imaging of vessel wall inflammation: the impact of {sup 18}F-FDG circulation time, injected dose, uptake parameters, and fasting blood glucose levels

    Energy Technology Data Exchange (ETDEWEB)

    Bucerius, Jan [Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, P.O. Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Maastricht University Medical Center, Department of Nuclear Medicine, Maastricht (Netherlands); Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht (Netherlands); University Hospital, RWTH Aachen, Department of Nuclear Medicine, Aachen (Germany); Mani, Venkatesh; Fayad, Zahi A. [Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, P.O. Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Moncrieff, Colin [Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, P.O. Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Machac, Josef [Mount Sinai School of Medicine, Division of Nuclear Medicine, Department of Radiology, New York, NY (United States); Fuster, Valentin [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); The Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid (Spain); Farkouh, Michael E. [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Mount Sinai School of Medicine, Cardiovascular Imaging Clinical Trials Unit, New York, NY (United States); Tawakol, Ahmed [Massachusetts General Hospital, Harvard University, Cardiac MR PET CT Program, Boston, MA (United States); Rudd, James H.F. [Cambridge University, Division of Cardiovascular Medicine, Cambridge (United Kingdom)

    2014-02-15

    {sup 18}F-FDG PET is increasingly used for imaging of vessel wall inflammation. However, limited data are available on the impact of methodological variables, i.e. prescan fasting glucose, FDG circulation time and injected FDG dose, and of different FDG uptake parameters, in vascular FDG PET imaging. Included in the study were 195 patients who underwent vascular FDG PET/CT of the aorta and the carotids. Arterial standardized uptake values ({sub mean}SUV{sub max}), target-to-background ratios ({sub mean}TBR{sub max}) and FDG blood-pool activity in the superior vena cava (SVC) and the jugular veins (JV) were quantified. Vascular FDG uptake values classified according to the tertiles of prescan fasting glucose levels, the FDG circulation time, and the injected FDG dose were compared using ANOVA. Multivariate regression analyses were performed to identify the potential impact of all variables described on the arterial and blood-pool FDG uptake. Tertile analyses revealed FDG circulation times of about 2.5 h and prescan glucose levels of less than 7.0 mmol/l, showing a favorable relationship between arterial and blood-pool FDG uptake. FDG circulation times showed negative associations with aortic{sub mean}SUV{sub max} values as well as SVC and JV FDG blood-pool activity, but positive correlations with aortic and carotid{sub mean}TBR{sub max} values. Prescan glucose levels were negatively associated with aortic and carotid{sub mean}TBR{sub max} and carotid{sub mean}SUV{sub max} values, but were positively correlated with SVC blood-pool uptake. The injected FDG dose failed to show any significant association with vascular FDG uptake. FDG circulation times and prescan blood glucose levels significantly affect FDG uptake in the aortic and carotid walls and may bias the results of image interpretation in patients undergoing vascular FDG PET/CT. The injected FDG dose was less critical. Therefore, circulation times of about 2.5 h and prescan glucose levels less than 7.0 mmol

  16. Relationship between Blood Mercury Concentration and Bone Mineral Density in Korean Men in the 2008–2010 Korean National Health and Nutrition Examination Survey

    Science.gov (United States)

    Kim, Yang Hee; Seo, Min Seok; Yim, Hyung Ji; Cho, Mi Ra

    2016-01-01

    Background The results of previous studies on the association between blood mercury (Hg) and bone mineral density (BMD) are inconsistent. We therefore used a large-scale nationwide representative sample of Korean men to investigate the relationship between these two parameters. Methods A nationwide cross-sectional study was conducted using data from the 2008 to 2010 Korean National Health and Nutrition Examination Survey to evaluate the relationship between blood Hg and BMD and the prevalence of osteopenia or osteoporosis in 1,190 men over 50 years of age. BMD was measured by dual-energy X-ray absorptiometry. Osteopenia and osteoporosis were diagnosed for each body site according to World Health Organization T-score criteria. Results After adjusting for age, body mass index, caloric energy and calcium intake, vitamin D levels, fish consumption, alcohol consumption, smoking, and exercise, quartiles of blood Hg were positively associated with femur neck T-scores in multiple linear regression analysis (β=0.06, P-value=0.03). Compared with the lowest blood Hg quartile, the odds ratios and 95% confidence intervals for diagnosis of osteopenia or osteoporosis in the second and fourth quartiles were 0.63 (0.41–0.99) and 0.57 (0.36–0.91), respectively, in the femur neck after adjusting for the same co-variables. Conclusion High blood Hg levels were associated with reduced odds of decreased femur neck BMD in Korean men. However, subgroup analysis did not show a significant protective effect of blood Hg on osteoporotic fractures. Further research is necessary to clarify the association between blood Hg and BMD. PMID:27688860

  17. 萹蓄总黄酮对离体大鼠血管舒张作用机制的探讨%Study on vasodilatation effects of total flavonoid from polygonum aviculare on blood vessel of rat in vitro

    Institute of Scientific and Technical Information of China (English)

    闻喜英; 王彬; 朱运波

    2011-01-01

    Objective To investigate the vasodilatation effects of total flavonoid from polygonum aviculare on rat thoracic aorta and its underlying mechanisms. Methods Total flavonoid from polygonum aviculare was gotten by extracted with 65% alcohol, gathered with polyamide, and eluted with 75% alcohol.The content of flavone was determined with rutoside as standard preparation. Normal rats thoracic aorta in vitro used as sample, BL-420E biological functional experiment system was utilized to record dilatation effect of total flavonoid on PE affecting pre-contracting blood vessel and the relation between dilatation effect of total flavonoid on blood vessel and calcium influx. Results Total flavonoids from polygonum aviculare can diastole contractions of thoracic aorta caused by PE. In calcium-free perfusion, gradually adding CaCl2 induced calcium influx. Clinical data showed dose-effect relation between drug and blood vessel contraction decreased in the total flavonoids from polygonum aviculare incubation rats than normal rats. Besides, total flavonoids from polygonum aviculare can obviously inhibit contraction of blood vascular circle induced by calcium releasing.Conclusion FP exerted a dose-dependent vasodilatation effect on rat isolated aorta rings by inhibiting Ca2+influx via L-type voltage-gated Ca2+ channels and Ca2+ release from sarcoplasmic reticulum, consequently decrease Ca2+ in vascular smooth muscle cells.%目的 研究萹蓄总黄酮(FP)对正常离体大鼠胸主动脉的舒张作用并对其机制进行初步探讨.方法 65%乙醇提取、聚酰胺富集、75%乙醇洗脱制得萹蓄总黄酮(FP),以芦丁为标准品测定FP中黄酮含量;以正常离体大鼠胸主动脉为标本,利用BL-420E生物机能实验系统记录FP对去氧肾上腺素(PE)预先收缩血管的舒张作用及FP舒张血管作用与外Ca2+内流、内Ca2+释放的关系.结果 FP可舒张PE引发的胸主动脉收缩的作用.在无Ca2+灌流液中,逐渐加入CaCl2引起外Ca2+内

  18. Assessment risk of osteoporosis in Chinese people: relationship among body mass index, serum lipid profiles, blood glucose, and bone mineral density

    Directory of Open Access Journals (Sweden)

    Cui RT

    2016-07-01

    Full Text Available Rongtao Cui,1 Lin Zhou,2 Zuohong Li,2 Qing Li,2 Zhiming Qi,2 Junyong Zhang3 1Department of Orthopedic and Trauma Surgery, Surgical Research, Duisburg-Essen University Hospital, Essen, Germany; 2Department of Orthopedics, Dalian Central Hospital, Dalian, 3Department of Gastroenterology, Shandong Provincial Hospital, Jinan, People’s Republic of China Objective: The aim of our study was to investigate the relationship among age, sex, body mass index (BMI, serum lipid profiles, blood glucose (BG, and bone mineral density (BMD, making an assessment of the risk of osteoporosis.Materials and methods: A total of 1,035 male and 3,953 female healthy volunteers (aged 41–95 years were recruited by an open invitation. The basic information, including age, sex, height, weight, waistline, hipline, menstrual cycle, and medical history, were collected by a questionnaire survey and physical examination. Serum lipid profiles, BG, postprandial blood glucose, and glycosylated hemoglobin were obtained after 12 hours fasting. BMD in lumbar spine was measured by dual-energy X-ray absorptiometry scanning.Results: The age-adjusted BMD in females was significantly lower than in males. With aging, greater differences of BMD distribution exist in elderly females than in males (P<0.001, and the fastigium of bone mass loss was in the age range from 51 to 55 in females and from 61 to 65 years in males. After adjustment for sex, there were significant differences in BMD among BMI-stratified groups in both males and females. The subjects with a BMI of <18.5 had a higher incidence of osteoporosis than BMI ≥18.5 in both sexes. BMD in type 2 diabetes mellitus with a BG of >7.0 mmol/L was lower than in people with BG of ≤7.0 mmol/L (P<0.001. People with serum high-density lipoprotein cholesterol levels of ≥1.56 mmol/L had a greater prevalence of osteoporosis compared with high-density lipoprotein cholesterol ≤1.55 mmol/L. Logistic regression with odds ratios showed that

  19. Vessel Operator System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operator cards are required for any operator of a charter/party boat and or a commercial vessel (including carrier and processor vessels) issued a vessel permit...

  20. Vessel Activity Record

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Activity Record is a bi-weekly spreadsheet that shows the status of fishing vessels. It records whether fishing vessels are fishing without an observer...

  1. 仿生构建具有一氧化氮自催化生成功能的人工血管材料%Layer-by-layer assembled selenium containing mimic artificial blood vessels with catalyzing NO generation

    Institute of Scientific and Technical Information of China (English)

    李岩冬; 王恺; 孔梅梅; 武文洁; 安军; 陈思原; 洪彦航; 孔德领; 王淑芳

    2011-01-01

    目的 利用有机硒催化一氧化氮(No)供体释放NO的能力设计一种新型人工血管支架材料。方法固载有机硒催化剂的聚乙烯亚胺( SePEI)作为聚阳离子,与聚阴离子聚谷氨酸(PGA)在静电纺丝得到的纳米纤维支架聚己内酯(PCL)表面层层自组装,用紫外和原子吸收进行了定性和定量的表征层层自组装结构;在还原型谷胱甘肽(GSH)的存在下测试材料催化分解NO供体亚硝基硫醇(RSNO)释放NO的能力,并进行相关生物性能的评价。结果材料对NO的催化释放过程相对稳定并且没有明显突释现象,80 h后仍能检测到NO产生。通过相关生物性能的检测,材料被证明基本没有毒性,并且在抗血小板凝聚方面具有显著作用。结论这种新型的血管支架材料在提高材料生物性能方面起到了很好的功效。%Objective A new style of artificial vessel scaffold was designed making the use of property of organoselenium catalyzing the releasing of Nitric oxide (NO). Methods Selenium-containing catalyst organoselenium immobilized polyethyleneimine (SePEI) as polycation and polyglutamic acid (PGA) as polyanion were alternately coated onto the surface of polycaprolactone (PCL) nanofiber scaffolds obtained by electrospinning to form the blood vessel scaffold. Self-assembly was characterized by UV and atomic absorption qualitatively and quantitatively. Catalytic generation of NO from the NO donors- RSNOs was tested under the existence of reducing agent RSH. Biological properties were also evaluated. Results The NO release was relatively stable with no significant burst appeared, and still could be detected after 80 hours of catalyzing. The material was proved to show little cytotoxicity, and displayed significant effect in inhibiting of platelet aggregation through biological testing. Conclusion The new style of artificial vessel scaffold has good effect on improving the biological properties of materials.

  2. Fluid-structure interaction analysis on the effect of vessel wall hypertrophy and stiffness on the blood flow in carotid artery bifurcation

    Science.gov (United States)

    Lee, Sang Hoon; Choi, Hyoung Gwon; Yoo, Jung Yul

    2012-11-01

    The effect of artery wall hypertrophy and stiffness on the flow field is investigated using three-dimensional finite element method for simulating the blood flow. To avoid the complexity due to the necessity of additional mechanical constraints, we use the combined formulation which includes both the fluid and structural equations of motion into single coupled variational equation. A P2P1 Galerkin finite element method is used to solve the Navier-Stokes equations for fluid flow and arbitrary Lagrangian-Eulerian formulation is used to achieve mesh movement. The Newmark method is employed for solving the dynamic equilibrium equations for linear elastic solid mechanics. The pulsatile, incompressible flows of Newtonian fluids constrained in the flexible wall are analyzed with Womersley velocity profile at the inlet and constant pressure at the outlet. The study shows that the stiffness of carotid artery wall affects significantly the flow phenomena during the pulse cycle. Similarly, it is found that the flow field is also strongly influenced by wall hypertrophy. This work was supported by Mid-career Researcher Program and Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0079936 & 2011-0029613).

  3. 护理干预对妊娠期糖尿病患者血糖及血管炎性因子水平影响%Diabetes Care Interventions in Patients with Gestational Diabetes Inflammatory Factor Levels Affect Blood Glucose and Blood Vessels

    Institute of Scientific and Technical Information of China (English)

    马常霞

    2015-01-01

    目的 探讨糖尿病护理门诊持续动态管理对妊娠期糖尿患者群血糖及血管炎性因子水平的影响.方法 妊娠期糖尿病患者80例,以数字卡片法随机分为两组,每组40例.对照组于产科孕产妇门诊给予一般孕期管理咨询及饮食指导.观察组患者在糖尿病护理门诊建立完整个人资料档案,给予正规的糖尿病饮食、运动培训及管理,通过咨询指导及危险因素干预,对比两组患者干预后围产期血糖水平以及体内血管炎性因子水平的干预效果.所获数据采用方差分析,t检验.结果干预后,两组空腹血糖、餐后2h血糖、糖化血红蛋白水平较治疗前明显下降,体内血管炎性指标C-反应蛋白、白介素-6及肿瘤坏死因子-a水平治疗后比较,差异有显著性(P<0.05).结论 糖尿病护理门诊可以对妊娠期糖尿患者群实施有效管理,稳定孕产期患者血糖水平,降低血管炎性因子水平.%0bjective To study the diabetes care clinics for dynamic management of gestational diabetes blood glu-cose and vascular inflammatory factor levels. Methods Select 80 cases of obstetric outpatient treated for gestational dia-betes patients, in digital card method were randomly divided into research group and the control group, 40 cases in each group. The control group in obstetric maternal outpatient to guide general management consulting and diet during pregnan-cy. Team in diabetes care clinics set up complete personal data files, gives the formal diabetes diet, exercise training and management, through consultations and risk factor intervention, intervention analysis of 2 groups of patients after perinatal blood sugar levels and blood vessels in the body inflammatory factor levels of intervention effect. Results After interven-tion, two groups fasting blood glucose (FBG), postprandial 2 hours blood glucose (2 HBG), glycosylated hemoglobin (HbA1c) level was significantly lower, the blood vessels in the body inflammatory

  4. Quartz crystal microbalance-with dissipation monitoring (QCM-D) for real time measurements of blood coagulation density and immune complement activation on artificial surfaces.

    Science.gov (United States)

    Andersson, Marcus; Andersson, Jonas; Sellborn, Anders; Berglin, Mattias; Nilsson, Bo; Elwing, Hans

    2005-07-15

    A recently developed variant of quartz crystal microbalance (QCM) called QCM-with dissipation monitoring (QCM-D) allows simultaneous and simple measurements of changes in adsorbed mass as well as the viscoelastic property (D-factor) of deposited protein layers on the sensor surface. We have taken the QCM-D technology a step further and demonstrated its advantages in the study of protein assembly as a consequence of surface induced immune complement activation, or contact activated blood coagulation. In the present study we have continued our QCM-D investigations of surface assembly of fibrin clot formation and complement activation and incubated differently modified quartz sensor surfaces in blood plasma and sera. Polymer surfaces used were spin-coated polyethylene, poly(ethylene terephtalate), poly(methylmetacrylate) and poly(dimethylsiloxane). Also used were sputtered titanium and heparin grafted surfaces. In this investigation we found that we could describe the surface induced coagulation with four independent parameters: (1) Time of onset of coagulation, (2) fibrin deposition rate, (3) total frequency shift at stable plateau, and (4) fibrin clot density. The most important finding was that the blood plasma clot density can be assessed with the use of D determinations and that the clot density varied significantly with the chemical composition of the surface. However, the D-factor did not give any new analytical information about the possible complement activation mechanisms. Nevertheless, the QCM-D was found to be a reliable tool for the analysis of surface induced complement activation. We also compared the QCM-D technique with traditional enzyme immuno assay (EIA) measurements of soluble products from the surface activation of the complement and coagulation systems. We found that the results from EIA and QCM-D measurements corresponded well for the complement activation but not for the coagulation, probably due to the biological complexity of the coagulation

  5. 血糖水平对急性脑血管病患者神经功能恢复的影响%The influence of blood sugar level on the recovery of patients' nerve function of acute cerebral vessel disease

    Institute of Scientific and Technical Information of China (English)

    郝淑梅; 石寄平; 谢艳萍

    2001-01-01

    @@ Background:Diabetes mellitus is one of risk factors leading to acute cerebral vessel disease(ACVD),and people have paid more attention to the fact that increase of blood sugar level after ACVD can aggravate nerve system impairment. Objective:To study the influence of blood sugar level increase on the recovery of nerve function of ACVD. Design:To make retrospective analysis on the relationship between prognosis and ACVD blood sugar level increase,the 157 patients lived in our hospital between March 1995 and March 2001.

  6. Flow Cytometric Quantification of Peripheral Blood Cell β-Adrenergic Receptor Density and Urinary Endothelial Cell-Derived Microparticles in Pulmonary Arterial Hypertension.

    Directory of Open Access Journals (Sweden)

    Jonathan A Rose

    Full Text Available Pulmonary arterial hypertension (PAH is a heterogeneous disease characterized by severe angiogenic remodeling of the pulmonary artery wall and right ventricular hypertrophy. Thus, there is an increasing need for novel biomarkers to dissect disease heterogeneity, and predict treatment response. Although β-adrenergic receptor (βAR dysfunction is well documented in left heart disease while endothelial cell-derived microparticles (Ec-MPs are established biomarkers of angiogenic remodeling, methods for easy large clinical cohort analysis of these biomarkers are currently absent. Here we describe flow cytometric methods for quantification of βAR density on circulating white blood cells (WBC and Ec-MPs in urine samples that can be used as potential biomarkers of right heart failure in PAH. Biotinylated β-blocker alprenolol was synthesized and validated as a βAR specific probe that was combined with immunophenotyping to quantify βAR density in circulating WBC subsets. Ec-MPs obtained from urine samples were stained for annexin-V and CD144, and analyzed by a micro flow cytometer. Flow cytometric detection of alprenolol showed that βAR density was decreased in most WBC subsets in PAH samples compared to healthy controls. Ec-MPs in urine was increased in PAH compared to controls. Furthermore, there was a direct correlation between Ec-MPs and Tricuspid annular plane systolic excursion (TAPSE in PAH patients. Therefore, flow cytometric quantification of peripheral blood cell βAR density and urinary Ec-MPs may be useful as potential biomarkers of right ventricular function in PAH.

  7. Protective effect of Dracocephalum heterophyllum Benth.on blood vessel endothelium of hypertensive rats%异叶青兰总黄酮对高血压大鼠血管内皮的保护作用

    Institute of Scientific and Technical Information of China (English)

    何雯; 邬利娅·伊明; 司丽君; 闫冬; 王雪飞; 萨迪克·诺莫诺夫; 帕尔哈提·克热木

    2013-01-01

    目的:研究异叶青兰总黄酮(Dracocephalumheterophyllum Benth flavonoid,DHBF)对高血压大鼠血管内皮的保护作用.方法:左肾动脉狭窄法建立“两肾一夹”高血压大鼠模型,设假手术组(Sham),模型组(Model),异叶青兰总黄酮低剂量组(DHBF-L)300 mg·kg 1·d-1、高剂量组(DHBF-H)600 mg·kg-1·d-1,卡托普利组(Captopril)20 mg·kg-1·d-1.灌胃给药6周,每周无创尾套法测量大鼠尾动脉收缩压.硝酸还原酶法测定血清中一氧化氮(NO)水平,放射免疫法测定心肌中ET-1含量,血浆中TXB2、6-keto-PGF1.含量,计算其比值.结果:异叶青兰总黄酮两剂量组能明显降低肾性高血压大鼠尾动脉收缩压(P<0.05,P<0.01),升高NO水平(P<0.05,P<0.01),降低ET水平(P<0.01),降低TXB2与6-keto-PGF1α比值(P<0.05).结论:异叶青兰总黄酮对高血压大鼠的血管内皮具有一定的保护作用.%OBJECTIVE To study the protective effect of Dracocephalum heterophyllum Benth flavonoid(DHBF) on blood vessel endothelium of hypertensive rats.METHODS Two-kidney-one-clip hypertensive rats were obtained by narrowing left kidney arteries.5 groups were divided as sham; model; DHBF low dose group (DHBF-L,300 mg·kg-1 ·d-1); DHBF high dose group (DHBF-H,600 mg· kg-1· d-1) and captopril (20 mg· kg-1) group.The drugs were given by intragastric administration for 6 weeks.Systolic blood pressure (SBP) was measured by tail cuff approach every week.After the sixth week,,the levels of NO in serum were measured by nitrate reductase method,The levels of ET in heart,TXB2,6-keto-PGF1α in plasma were all measured by radioimmunoassay and the ratio of TXB2 and 6-keto-PGF1α were calculated.RESULTS DHBF significantly reduced hypertensive rats' blood pressure(P<0.05,P<0.01),increased the concentration of NO (P<0.05,P<0.01)while decreased the content of ET(P<0.01) ; reduced the ratio of TXB2and 6-keto-PGF10 (P<0.05).CONCLUSION The re sults suggest that DHBF could be used to

  8. Expression of Slit2 and its correlation with lymphatic vessel density in hypopharyngeal squamous cell carcinoma%Slit2在喉咽鳞癌中的表达及其与LVD关系的研究

    Institute of Scientific and Technical Information of China (English)

    钱晔; 雷大鹏; 金童; 刘大昱; 许风雷; 潘新良

    2012-01-01

    Objective To investigate the expression of Slit2 and its correlation with the lymphatic vessel density (LVD) in human hypopharyngeal squamous cell carcinomas, and to analyze their influences on the biological behavior of human hypopharyngeal squamous cell carcinoma. Methods The expressions of Slit2 and D2-40 -labeled lymphatic vessel density (LVD) were measured by immunochemical staining in 66 hypopharyngeal squamous cell carcinoma and 42 normal tissue samples. Results The positive rates of Slit2 in cancerous tissues and para-cancerous tissues were 65.2 % and 40. 5 % , respectively. Expression rate of Slit2 and LVD were closely associated with tumor size, TNM staging, and lymph node metastasis. The numeration of LVD was increased in Slit2 -positive tissues. Expression of Slit2 showed a positive correlation with LVD( rs = 0. 430, P < 0. 05). Conclusion Expression of Slit2 and enumeration of LVD were significantly higher in hypopharyngeal squamous cell carcinoma than in normal muco-sa. Their close correlations to the tumor invasion and lymph node metastasis suggest that Slit2 might mediate new lymphatic vessel formation in the tumors.%目的 研究喉咽鳞状细胞癌中神经迁移蛋白Slit2的表达情况及其与淋巴管密度(LVD)的关系,探讨Slit2的表达和LVD计数与喉咽鳞癌生物学行为的相关性.方法 用免疫组织化学法检测喉咽鳞癌中Slit2蛋白表达及LVD计数,分析二者与喉咽鳞癌病理分型、分级和预后的关系.结果 Slit2蛋白在喉咽鳞癌和癌旁组织中的表达率分别为65.2%和40.5%,差异有统计学意义(x2=6.329,P<0.05);Slit2蛋白表达情况与肿瘤大小、TNM分期、淋巴结转移显著相关;LVD与肿瘤大小、病理类型、浸润深度、TNM分期和淋巴节转移显著相关.Slit2表达和LVD计数与肿瘤的发病年龄、部位等均无关.喉咽鳞癌中Slit2阳性表达者周边LVD计数高于Slit2阴性表达者,差异有统计学意义(t=2.273,P<0.05)

  9. 静电纺丝血管组织工程支架构建仿生血管微环境的研究进展%Research advances in construction of mimetic natural blood vessel microenvironment by electrospinning

    Institute of Scientific and Technical Information of China (English)

    王皓; 彭永康; 孔德领; 杨军

    2009-01-01

    静电纺丝是近年来制备纳米纤维组织工程支架的主要技术,可用于多种天然或合成高分子材料的成型加工,其制备的纳米纤维支架具有体内细胞外基质(ECM)的仿生结构和特点,是最有发展前景的仿生构建细胞外基质的新技术.综述了多种静电纺丝技术以及静电纺丝支架的生物活性分子修饰在小口径人工血管的仿生微环境构建研究中的研究进展.%Electrospinning has been, in recent years, a popular choice for producing tissue engineering scaffolds with various natural and synthetic polymers. The structure of nanofibers by electrospun is similar to the extracellular matrix (ECM) in vivo in many characteristics. Electrospinning is a new technique to construct nanofiber scaffolds for mimetic natural ECM. In this paper, review is given on various methods of electrospinning and modifications of nanofibers by bioactive factors which are used in construction of mimetic natural small diameter blood vessel microenvironment.

  10. Osteoid osteoma - the CT vessel sign

    Energy Technology Data Exchange (ETDEWEB)

    Yaniv, Gal; Shabshin, Noga; Sharon, Michal; Garniack, Alex [Sheba Medical Center, Dept. of Diagnostic Imaging, Tel Hashomer (Israel); Liberman, Boaz [Sheba Medical Center, Division of Orthopedics, Tel Hashomer, Sackler School of Medicine, Tel Aviv (Israel); Rimon, Uri [Sheba Medical Center, Dept. of Diagnostic Imaging, Tel Hashomer, Sackler School of Medicine, Tel Aviv (Israel); Eshed, Iris [Sheba Medical Center, Dept. of Diagnostic Imaging, Tel Hashomer, Tel Aviv University Sackler School of Medicine, Tel Aviv (Israel)

    2011-10-15

    To evaluate whether the presence of a feeding vessel in proximity to osteoid osteomas of long bones on multidetector CT (MDCT) can be an adjuvant clue for the diagnosis of osteoid osteoma. Forty-nine CT scans of patients with radiological and clinical diagnosis of osteoid osteoma of long bones and a control group of 20 CT scans of patients with cortical-based lesions other then osteoid osteoma were analyzed. Two radiologists evaluated the CT images in consensus for the presence of a blood vessel in the same axial slices in which the nidus of osteoid osteoma was seen and to determine the incidence. In 39 cases (79.6%) of osteoid osteoma, a blood vessel either entered the nidus (23 patients) or was seen in proximity to it (16 patients). This was significantly different (P<0.05) from the cortical-based lesions, in which only two CT scans (10%) showed a blood vessel in the lesion's proximity. In the majority of osteoid osteoma lesions in long bones, a blood vessel can be seen on MDCT either entering the nidus itself or in its proximity. The role of this vessel in the lesion pathogenesis and whether it improves diagnostic accuracy need further evaluation. (orig.)

  11. Applied anatomy of the relation of the blood vessels and the nerves in the neck to cervical vertebrae%颈部相关血管和神经与颈椎间关系的应用解剖

    Institute of Scientific and Technical Information of China (English)

    刘学敏; 武志兵; 王俊生; 扬永强

    2005-01-01

    背景:颈椎病手术治疗时,常用颈椎前外侧途径,主要显露颈椎椎体、椎间盘、钩椎关节等部位.近年来这方面的报道多为对其局部性的研究,特别是对颈椎与对应的血管神经距离数据的观测研究较少.目的:观测颈部血管与神经的关系及其与颈椎的距离,为颈椎病手术治疗中预防医源性血管和神经损伤提供帮助.设计:以解剖学标本为实验对象,单一样本研究.单位:一所医学院解剖教研室.对象:2003-07/2004-05在长治医学院解剖教研室完成,成人防腐标本20具40侧(由长治医学院解剖教研室提供),男36侧,女4侧.方法:观测了40侧成人标本颈部血管与神经的伴行关系,颈部血管的长度及起止点与相邻颈椎间的距离.主要观察指标:①相关动脉与神经的伴行关系.②相关动脉的长度及其起止点与相邻颈椎的距离.结果:20具标本40侧均进入结果分析.面动脉与舌神经伴行,起点距相邻椎体C3为(18.5±7.2)mm.舌动脉与舌下神经伴行,起点距相邻椎体C2~3为(19.7±8.4)mm.甲状腺上动脉与喉上神经外支伴行,起点距相邻椎体C3为(17.0±5.7)mm,止点距相邻椎体C5为(18.2±2.5)mm.喉上动脉与喉上神经内支伴行,起点距相邻椎体C3为(15.7±6.7)mm,止点距相邻椎体C3为(19.7±5.8)mm.甲状腺下动脉起点距相邻椎体C7为(17.3±5.5)mm,止点距相邻椎体C7为(11.3±3.4)mm.结论:在颈椎病手术中,不同部位的手术途径,应该注意特定部位的解剖结构,以减少医源性血管、神经损伤.%BACKGROUND: The operation on cervical spondylosis is usually done through anterolateral cervical vertebrae to mainly expose cervical vertebrae,intervertebral disc, hook joint and so on. The recent reports are mostly local studies. The observation data of the distance between cervical vertebrae and the corresponding nervus vascularis is limited.OBJECTIVE: The relation of the blood vessels and nerves to cervical vertebrae was

  12. EFFECTS OF STRAIN, CAGE DENSITY AND POSITION ON IMMUNE RESPONSE TO VACCINES AND BLOOD PARAMETERS IN LAYER PULLETS

    Directory of Open Access Journals (Sweden)

    Z. B