Sample records for primo vascular system

  1. Primo Vascular System in the Subarachnoid Space of a Mouse Brain

    PubMed Central

    Moon, Sang-Ho; Cha, Richard; Lim, Jae-Kwan; Soh, Kwang-Sup

    2013-01-01

    Objective. Recently, a novel circulatory system, the primo vascular system (PVS), was found in the brain ventricles and in the central canal of the spinal cord of a rat. The aim of the current work is to detect the PVS along the transverse sinuses between the cerebrum and the cerebellum of a mouse brain. Materials and Methods. The PVS in the subarachnoid space was analyzed after staining with 4′,6-diamidino-2-phenylindole (DAPI) and phalloidin in order to identify the PVS. With confocal microscopy and polarization microscopy, the primo vessel underneath the sagittal sinus was examined. The primo nodes under the transversal sinuses were observed after peeling off the dura and pia maters of the brain. Results. The primo vessel underneath the superior sagittal sinus was observed and showed linear optical polarization, similarly to the rabbit and the rat cases. The primo nodes were observed under the left and the right transverse sinuses at distances of 3,763 μm and 5,967 μm. The average size was 155 μm × 248 μm. Conclusion. The observation of primo vessels was consistent with previous observations in rabbits and rats, and primo nodes under the transverse sinuses were observed for the first time in this work. PMID:23781258

  2. The Meanings and Prospects of Primo Vascular System from the Viewpoint of Historical Context

    PubMed Central

    Jeon, Jongwook; Lee, Sanghun

    2013-01-01

    The aim of this overview is to evaluate the primo vascular system research in the context of the history of meridian theory and the modern meanings of it. The 12 meridian systems were naturally presupposed in the conventional study of the meridians and acupuncture. But the excavations of Mawang-tui old documents and Sichuan Mianyang wooden puppet revealed the primordial concepts of meridians uncolored by the numerological cosmology of Han era. Further, the meridian map of horse, cow and hawk show another resemblance to the primordial type of meridians. Modern meridian theory has been challenged by the material based scientific theory and the primo vascular theory presents the most radical answer for it. It aims to reveal the anatomical entity of meridians. However, the study of primo vascular system is unexpectedly opening the new horizon of scientific integration of East and West beyond the mere searching for anatomical entity of meridians. Conclusions we have drawn from the historical reviews are, (1) the surface structure of the body reflects the physiopathological changes of inside the body, (2) by stimulating specific sites on the surface, it is possible to acquire therapeutic effects of certain symptoms, and (3) numbers and locations of meridian acupoints are variable among traditional meridian theories. PMID:23762137

  3. [From Bonghan system to primo vascular system:the thought on the substantial study on meridian points].

    PubMed

    Lin, Dong; Huang, Xiaozhen; Zhuang, Wanyu; Lin, Lili

    2017-01-12

    Through the systematic analysis on the primo vascular system (PVS) in recent years, we believe that in recent years, more and more studies have indicated that PVS is distributed in reticulate structure in every part of body, such as vessels, lymphangions, nerves, brain, spinal cords and internal organs, and it contains a large amount of immunocytes and has involved in the physiological or pathological process of the immunity and circulation in the body. There are the evidences to prove that in morphology and cytobiology. But, nowadays, there is no way to explain its effect characters. On the basis of the study on living matter characteristics, a breakthrough is possibly made through the systematic cooperation even though it is the difficulty to detect the life function effect. It is especially displayed in the substantial study on meridian points. Hence, the study on the law of meridian point effects on the basis of clinical practice has to be focused on in the substantial study on meridian points.

  4. Primo vessel inside a lymph vessel emerging from a cancer tissue.

    PubMed

    Lee, Sungwoo; Ryu, Yeonhee; Cha, Jinmyung; Lee, Jin-Kyu; Soh, Kwang-Sup; Kim, Sungchul; Lim, Jaekwan

    2012-10-01

    Primo vessels were observed inside the lymph vessels near the caudal vena cava of a rabbit and a rat and in the thoracic lymph duct of a mouse. In the current work we found a primo vessel inside the lymph vessel that came out from the tumor tissue of a mouse. A cancer model of a nude mouse was made with human lung cancer cell line NCI-H460. We injected fluorescent nanoparticles into the xenografted tumor tissue and studied their flow in blood, lymph, and primo vessels. Fluorescent nanoparticles flowed through the blood vessels quickly in few minutes, and but slowly in the lymph vessels. The bright fluorescent signals of nanoparticles disappeared within one hour in the blood vessels but remained much longer up to several hours in the case of lymph vessels. We found an exceptional case of lymph vessels that remained bright with fluorescence up to 24 hours. After detailed examination we found that the bright fluorescence was due to a putative primo vessel inside the lymph vessel. This rare observation is consistent with Bong-Han Kim's claim on the presence of a primo vascular system in lymph vessels. It provides a significant suggestion on the cancer metastasis through primo vessels and lymph vessels. Copyright © 2012. Published by Elsevier B.V.

  5. PRIMO: An Interactive Homology Modeling Pipeline.

    PubMed

    Hatherley, Rowan; Brown, David K; Glenister, Michael; Tastan Bishop, Özlem

    2016-01-01

    The development of automated servers to predict the three-dimensional structure of proteins has seen much progress over the years. These servers make calculations simpler, but largely exclude users from the process. In this study, we present the PRotein Interactive MOdeling (PRIMO) pipeline for homology modeling of protein monomers. The pipeline eases the multi-step modeling process, and reduces the workload required by the user, while still allowing engagement from the user during every step. Default parameters are given for each step, which can either be modified or supplemented with additional external input. PRIMO has been designed for users of varying levels of experience with homology modeling. The pipeline incorporates a user-friendly interface that makes it easy to alter parameters used during modeling. During each stage of the modeling process, the site provides suggestions for novice users to improve the quality of their models. PRIMO provides functionality that allows users to also model ligands and ions in complex with their protein targets. Herein, we assess the accuracy of the fully automated capabilities of the server, including a comparative analysis of the available alignment programs, as well as of the refinement levels used during modeling. The tests presented here demonstrate the reliability of the PRIMO server when producing a large number of protein models. While PRIMO does focus on user involvement in the homology modeling process, the results indicate that in the presence of suitable templates, good quality models can be produced even without user intervention. This gives an idea of the base level accuracy of PRIMO, which users can improve upon by adjusting parameters in their modeling runs. The accuracy of PRIMO's automated scripts is being continuously evaluated by the CAMEO (Continuous Automated Model EvaluatiOn) project. The PRIMO site is free for non-commercial use and can be accessed at https://primo.rubi.ru.ac.za/.

  6. PRIMO: An Interactive Homology Modeling Pipeline

    PubMed Central

    Glenister, Michael

    2016-01-01

    The development of automated servers to predict the three-dimensional structure of proteins has seen much progress over the years. These servers make calculations simpler, but largely exclude users from the process. In this study, we present the PRotein Interactive MOdeling (PRIMO) pipeline for homology modeling of protein monomers. The pipeline eases the multi-step modeling process, and reduces the workload required by the user, while still allowing engagement from the user during every step. Default parameters are given for each step, which can either be modified or supplemented with additional external input. PRIMO has been designed for users of varying levels of experience with homology modeling. The pipeline incorporates a user-friendly interface that makes it easy to alter parameters used during modeling. During each stage of the modeling process, the site provides suggestions for novice users to improve the quality of their models. PRIMO provides functionality that allows users to also model ligands and ions in complex with their protein targets. Herein, we assess the accuracy of the fully automated capabilities of the server, including a comparative analysis of the available alignment programs, as well as of the refinement levels used during modeling. The tests presented here demonstrate the reliability of the PRIMO server when producing a large number of protein models. While PRIMO does focus on user involvement in the homology modeling process, the results indicate that in the presence of suitable templates, good quality models can be produced even without user intervention. This gives an idea of the base level accuracy of PRIMO, which users can improve upon by adjusting parameters in their modeling runs. The accuracy of PRIMO’s automated scripts is being continuously evaluated by the CAMEO (Continuous Automated Model EvaluatiOn) project. The PRIMO site is free for non-commercial use and can be accessed at https://primo.rubi.ru.ac.za/. PMID:27855192

  7. Formative research on the primo vascular system and acceptance by the korean scientific community: the gap between creative basic science and practical convergence technology.

    PubMed

    Kim, Hoon Gi

    2013-12-01

    The purpose of this study was to trace the formative process of primo vascular system (PVS) research over the past decade and to describe the characteristics of the Korean scientific community. By publishing approximately 30 papers in journals ranking in the Science Citation Index (Expanded), the PVS research team actively convinced domestic and international scientists of the anatomical existence of the PVS and its possible application to Korean and Western medicine. In addition, by sharing the PVS observation technique, the team promoted the dissemination and further pursuit of the research. In 2012, however, PVS researchers performed smaller scale research without advancing to a higher level as compared to the early days. The main reasons were found to be the Korean Research and Development policy of supporting creative, small-scale basic research and applied research of Western scientific fields that promised potentially greater success on an extensive scale; the indifference concerning, and the disbelief in, the existence of a new circulatory system were shown by the Western medical community. In addition, the Oriental medical community was apathetic about working with the PVS team. Professors Kwang-Sup Soh and Byung-Cheon Lee were the prime movers of PVS research under difficult conditions. Spurred by their belief in the existence and significance of the PVS, they continued with their research despite insufficient experimental data. The Korean scientific community is not ready to promote the Korea-oriented creative field of the PVS team. Copyright © 2013. Published by Elsevier B.V.

  8. The GBT Primos Program: 7 Years of Astronomical Discovery

    NASA Astrophysics Data System (ADS)

    Corby, Joanna F.; McGuire, Brett A.; Hollis, Mike; Lovas, Frank J.; Jewell, Philip; Remijan, Anthony

    2014-06-01

    The GBT PRebiotic Interstellar MOlecule Survey (PRIMOS) towards Sgr B2N is the deepest, most complete spectral line survey in the range of 300MHz - 49 GHz. PRIMOS enables astronomers, chemists, and biologists to test theories of molecular formation, the origins of organic chemistry and the molecular complexity and physical and kinematic structure of material in our Galaxy. To date, PRIMOS data have resulted in 14 refereed publications since 2007, demonstrating the power of centimeter wave spectroscopy for detecting new organic species and revealing the significance of non-LTE effects including maser amplification in the cm-wave spectra of organic molecules. The survey has additionally advertised molecular astrophysics in public lectures, summer undergraduate diversity programs, and high school student projects. While the GBT is the only telescope in the world capable of conducting the PRIMOS Survey, PRIMOS data couples with newly available broad-bandwidth telescopes including the Jansky Very Large Array and ALMA. Synergistic observations with ALMA will be necessary to fully characterize the spectra of molecular material and determine excitation mechanisms leading to observed line radiation. This presentation provides an overview of the PRIMOS program, highlights PRIMOS science, and describes how the entire astronomical community can obtain the data for their own research.

  9. Conjugate Magnetic Observations in the Polar Environments by PRIMO and AUTUMNX

    NASA Astrophysics Data System (ADS)

    Chi, P. J.; Russell, C. T.; Strangeway, R. J.; Raymond, C. A.; Connors, M. G.; Wilson, T. J.; Boteler, D. H.; Rowe, K.; Schofield, I.

    2014-12-01

    While magnetically conjugate observations by ground-based magnetometers are available at both high and low magnetic latitudes, few have been established at auroral latitudes to monitor the hemispheric asymmetry of auroral electric currents and its impact to geospace dynamics. Due to the limitations of global land areas, the only regions where conjugate ground-based magnetic observations can cover the full range of auroral latitudes are between Quebec, Canada and West Antarctica. Funded by the Canadian Space Agency, the AUTUMNX project is currently emplacing 10 ground-based magnetometers in Quebec, Canada, and will provide the magnetic field observations in the Northern Hemisphere. The proposed U.S. Polar Region Interhemispheric Magnetic Observatories (PRIMO) project plans to establish six new ground-based magnetometers in West Antarctica at L-values between 3.9 and 10.1. The instrument is based on the new low-power fluxgate magnetometer system recently developed at UCLA for operation in the polar environments. The PRIMO magnetometers will operate on the power and communications platform well proven by the POLENET project, and the six PRIMO systems will co-locate with existing ANET stations in the region for synergy in logistic support. Focusing on the American longitudinal sector and leveraging infrastructure through international collaborations, PRIMO and AUTUMNX can monitor the intensity and location of auroral electrojets in both hemispheres simultaneously, enabling the first systematic interhemispheric magnetic observations at auroral latitudes.

  10. Effective isolation of primo vessels in lymph using sound- and ultrasonic-wave stimulation.

    PubMed

    Park, Do-Young; Lee, Hye-Rie; Rho, Min-Suk; Lee, Sang-Suk

    2014-12-01

    The effects of stimulation with sound and ultrasonic waves of a specific bandwidth on the microdissection of primo vessels in lymphatic vessels of rabbit were investigated. The primo vessels stained with alcian-blue dye injected in the lymph nodes were definitely visualized and more easily isolated by sound-wave vibration and ultrasonic stimulation applied to rabbits at various frequencies and intensities. With sound wave at 7 Hz and ultrasonic waves at 2 MHz, the probability of detecting the primo vessels was improved to 90%; however, without wave stimulation the probability of discovering primo vessels was about 50% only. Sound and ultrasonic waves at specific frequency bands should be effective for microdissection of the primo vessels in the abdominal lymph of rabbit. We suggest that oscillation of the primo vessels by sound and ultrasonic waves may be useful to visualize specific primo structure, and wave vibration can be a very supportive process for observation and isolation of the primo vessels of rabbits. Copyright © 2014. Published by Elsevier B.V.

  11. A new definition of an acupuncture meridian.

    PubMed

    Kovich, Fletcher

    2018-05-11

    This article provides a new definition of an acupuncture meridian. It suggests that a meridian consists of a distal tract of tissue that is affected by organ function. In the 1960's, Kim discovered the primo vascular system, and regarded the superficial primo vessels as equating to the meridians. Instead, this article suggests that the superficial primo vessels merely underlie the meridians, in that they enable their creation, which is why some meridians are said to occur along the paths of superficial primo vessels. But the meridians themselves do not have a dedicated anatomical structure; instead they are merely tracts of tissue whose normal function is impeded when the related abdominal organ is stressed. It is hypothesised that the organ information is communicated in electrical waves that may travel through the connective tissue sheaths of the superficial primo vessels. Hence the primo vessels serve as an inadvertent transport for this information, but the organ information is independent of the physiological purpose of the primo vascular system, as are the resultant meridians. Copyright © 2018. Published by Elsevier B.V.

  12. FindIt@Flinders: User Experiences of the Primo Discovery Search Solution

    ERIC Educational Resources Information Center

    Jarrett, Kylie

    2012-01-01

    In September 2011, Flinders University Library launched FindIt@Flinders, the Primo discovery layer search to provide simultaneous results from the Library's collections and subscription databases. This research project was an exploratory case study which aimed to show whether students were finding relevant information for their course learning and…

  13. SU-F-T-367: Using PRIMO, a PENELOPE-Based Software, to Improve the Small Field Dosimetry of Linear Accelerators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Benmakhlouf, H; Andreo, P; Brualla, L

    2016-06-15

    Purpose: To calculate output correction factors for Varian Clinac 2100iX beams for seven small field detectors and use the values to determine the small field output factors for the linacs at Karolinska university hospital. Methods: Phase space files (psf) for square fields between 0.25cm and 10cm were calculated using the PENELOPE-based PRIMO software. The linac MC-model was tuned by comparing PRIMO-estimated and experimentally determined depth doses and lateral dose-profiles for 40cmx40cm fields. The calculated psf were used as radiation sources to calculate the correction factors of IBA and PTW detectors with the code penEasy/PENELOPE. Results: The optimal tuning parameters ofmore » the MClinac model in PRIMO were 5.4 MeV incident electron energy and zero energy spread, focal spot size and beam divergence. Correction factors obtained for the liquid ion chamber (PTW-T31018) are within 1% down to 0.5 cm fields. For unshielded diodes (IBA-EFD, IBA-SFD, PTW-T60017 and PTW-T60018) the corrections are up to 2% at intermediate fields (>1cm side), becoming down to −11% for fields smaller than 1cm. The shielded diode (IBA-PFD and PTW-T60016) corrections vary with field size from 0 to −4%. Volume averaging effects are found for most detectors in the presence of 0.25cm fields. Conclusion: Good agreement was found between correction factors based on PRIMO-generated psf and those from other publications. The calculated factors will be implemented in output factor measurements (using several detectors) in the clinic. PRIMO is a userfriendly general code capable of generating small field psf and can be used without having to code own linac geometries. It can therefore be used to improve the clinical dosimetry, especially in the commissioning of linear accelerators. Important dosimetry data, such as dose-profiles and output factors can be determined more accurately for a specific machine, geometry and setup by using PRIMO and having a MC-model of the detector used.« less

  14. Quality control and primo-diagnosis of transurethral bladder resections with full-field OCT

    NASA Astrophysics Data System (ADS)

    Montagne, P.; Ducesne, I.; Anract, J.; Yang, C.; Sibony, M.; Beuvon, F.; Delongchamps, N. B.; Dalimier, E.

    2017-02-01

    Transurethral resections are commonly used for bladder cancer diagnosis, treatment and follow-up. Cancer staging relies largely on the analysis of muscle in the resections; however, muscle presence is uncertain at the time of the resection. An extemporaneous quality control tool would be of great use to certify the presence of muscle in the resection, and potentially formulate a primo-diagnosis, in order to ensure optimum patient care. Full-field optical coherence tomography (FFOCT) offers a fast and non-destructive method of obtaining images of biological tissues at ultrahigh resolution (1μm in all 3 directions), approaching traditional histological sections. This study aimed to evaluate the potential of FFOCT for the quality control and the primo-diagnosis of transurethral bladder resections. Over 70 transurethral bladder resections were imaged with FFOCT within minutes, shortly after excision, and before histological preparation. Side-by-side comparison with histology allowed to establish reading criteria for the presence of muscle and cancer in particular. Images of 24 specimens were read blindly by three non-pathologists readers: two resident urologists and a junior bio-medical engineer, who were asked to notify the presence of muscle and tumor. Results showed that after appropriate training, 96% accuracy could be obtained on both tumour and muscle detection. FFOCT is a fast and nondestructive imaging technique that provides analysis results concordant with histology. Its implementation as a quality control and primo-diagnosis tool for transurethral bladder resections in the urology suite is feasible and lets envision high value for the patient.

  15. Quantifying Hemispheric Asymmetry of Auroral Currents by Polar Region Interhemispheric Magnetic Observatories (PRIMO)

    NASA Astrophysics Data System (ADS)

    Chi, P. J.; Russell, C. T.; Strangeway, R. J.; Connors, M. G.; Wilson, T. J.; Angelopoulos, V.; Anderson, B. J.; Kadokura, A.

    2016-12-01

    Previous observations have demonstrated that substorm auroras and the associated electric currents can exhibit substantial north-south asymmetry. Possible mechanisms that cause this asymmetry include the penetration of IMF By into the magnetotail, the difference in ionospheric conductivity due to the dipole tilt angle, and the difference in solar wind dynamo efficiency due to IMF Bx combined with the tilt angle. The relative importance of these factors, however, has not been determined, due to paucity of observations in the southern hemisphere. To resolve this difficulty, we propose to establish three new stations in West Antarctica for measuring geomagnetic perturbations. The three magnetometer stations are located at Lepley Lunatak, Union Glacier, and Whitmore Mountains, between -2° W and 7° W magnetic longitude at L-values 4, 6, and 8. These locations are magnetically conjugate to the recently established AUTUMNX magnetometers along the eastern shore of the Hudson Bay, enabling unique conjugate observations by two magnetometer chains at auroral latitudes and subauroral latitudes when close to midnight. These conjugate magnetic field observations, with concurrent satellite measurements by the AMPERE constellation and the Heliophysics System Observatory, can differentiate between magnetospheric and ionospheric contributions in the hemispheric asymmetry. The comparison with the conjugate observations at the Syowa and Iceland stations can shed light on the longitudinal extent of the hemispheric asymmetry. The PRIMO fluxgate magnetometer system includes a dedicated power and data communications platform developed by UNAVCO and successfully operated at ANET stations in the same region. The three PRIMO systems are co-located with existing ANET stations, facilitating logistic efficiencies such as transportation, cross-trained personnel, and common components. Our plan follows recommendations by the latest Heliophysics Decadal Study for ground-based observations

  16. Primo Levi and the Periodic Table: Teaching Chemistry Using A Literary Text (Excerpt)

    ERIC Educational Resources Information Center

    Osorio, Viktoria Klara Lakatos; Tiedemann, Peter Wilhelm; Porto, Paulo Alves

    2007-01-01

    The excerpts from The Periodic Table book written by Primo Levi is discussed related to chemical concepts. The use of a literary text as a starting point of discussions of chemical concepts has allowed the integration of various topics covered in separate courses of the undergraduate program in chemistry.

  17. The Publicly Available Prebiotic Interstellar Molecular Survey (primos): Expanding Spectroscopic Characterizations, Extending to New Sources, and Adding to the Known Molecular Inventory

    NASA Astrophysics Data System (ADS)

    McGuire, Brett A.; Carroll, P. Brandon; Corby, Joanna F.; Loomis, Ryan A.; Blake, Geoffrey A.; Hollis, Jan M.; Lovas, Frank J.; Jewell, Philip R.; Remijan, Anthony J.

    2013-06-01

    The publicly available Green Bank Telescope PRebiotic Interstellar MOlecular Survey (PRIMOS) conducted towards Sgr B2(N) provides high resolution, high-sensitivity observations with near-continuous frequency coverage from ˜300 MHz - 50 GHz. Of the eleven new molecular detections in the last year, five (45%) are a direct result of the PRIMOS observations. Further, these observations have recently been used to detect the predicted, but previously unobserved, J = 1-0 and J=2-1 transitions of the newly detected l-C_3H^+ ion. Here, we discuss the analysis of these transitions, as well as recent work to extend the PRIMOS observations to three new regions of interest: VY Canis Majoris, IRC+10216, and NGC 2023. Finally, we highlight the utility of cm-wave surveys in new molecular detections, as well as the value of publicly-available surveys in the approaching era of data-enabled, analysis-limited astrochemistry.

  18. The GBT PRIMOS Project - A Broadband Spectral Line Survey of SgrB2N from 300 MHz to 46 GHz

    NASA Astrophysics Data System (ADS)

    Remijan, Anthony J.; Hollis, J. M.; Jewell, P. R.; Lovas, F.; Corby, J.

    2013-01-01

    Broadband, very sensitive, high spectral resolution spectral line surveys in recent years have made profound impacts into the understanding of interstellar reaction processes and in the identification of new molecular material in astronomical environments. Molecular line surveys are studies of the spectra of astronomical sources over a wide and usually continuous range of frequencies in order to determine the chemical composition (i.e., "molecular inventory"), physical properties (temperature, density), and kinematics of such regions. The National Radio Astronomy Observatory's (NRAO) 100-m Robert C. Byrd Green Bank Telescope (GBT) PRebiotic Interstellar MOlecule Survey (PRIMOS) Legacy Project started in Jan 2008 and concluded in July 2011. The PRIMOS project recorded a nearly frequency-continuous astronomical spectrum from 300 MHz to 46 GHz towards the Sgr B2(N) molecular cloud, with the pointing position centered on the Large Molecule Heimat (LMH). The PRIMOS data have resulted in numerous new detections and discoveries in astrochemistry. The data have also been widely used to demonstrate advances in molecular astrophysics in a variety of venues and have been instrumental in training the next generation of astronomers and chemists. The GBT is the only telescope in the world capable of making these groundbreaking discoveries. This presentation will highlight the recent successes from the survey and how to access these publically-available observations.

  19. THE DETECTION OF INTERSTELLAR ETHANIMINE (CH{sub 3}CHNH) FROM OBSERVATIONS TAKEN DURING THE GBT PRIMOS SURVEY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Loomis, Ryan A.; Zaleski, Daniel P.; Steber, Amanda L.

    2013-03-01

    We have performed reaction product screening measurements using broadband rotational spectroscopy to identify rotational transition matches between laboratory spectra and the Green Bank Telescope PRIMOS radio astronomy survey spectra in Sagittarius B2 North (Sgr B2(N)). The broadband rotational spectrum of molecules created in an electrical discharge of CH{sub 3}CN and H{sub 2}S contained several frequency matches to unidentified features in the PRIMOS survey that did not have molecular assignments based on standard radio astronomy spectral catalogs. Several of these transitions are assigned to the E- and Z-isomers of ethanimine. Global fits of the rotational spectra of these isomers in themore » range of 8-130 GHz have been performed for both isomers using previously published mm-wave spectroscopy measurements and the microwave measurements of the current study. Possible interstellar chemistry formation routes for E-ethanimine and Z-ethanimine are discussed. The detection of ethanimine is significant because of its possible role in the formation of alanine-one of the twenty amino acids in the genetic code.« less

  20. Pressurized vascular systems for self-healing materials

    PubMed Central

    Hamilton, A. R.; Sottos, N. R.; White, S. R.

    2012-01-01

    An emerging strategy for creating self-healing materials relies on embedded vascular networks of microchannels to transport reactive fluids to regions of damage. Here we investigate the use of active pumping for the pressurized delivery of a two-part healing system, allowing a small vascular system to deliver large volumes of healing agent. Different pumping strategies are explored to improve the mixing and subsequent polymerization of healing agents in the damage zone. Significant improvements in the number of healing cycles and in the overall healing efficiency are achieved compared with prior passive schemes that use only capillary forces for the delivery of healing agents. At the same time, the volume of the vascular system required to achieve this superior healing performance is significantly reduced. In the best case, nearly full recovery of fracture toughness is attained throughout 15 cycles of damage and healing, with a vascular network constituting just 0.1 vol% of the specimen. PMID:21957119

  1. Vascular involvement in systemic sclerosis (scleroderma)

    PubMed Central

    Pattanaik, Debendra; Brown, Monica; Postlethwaite, Arnold E

    2011-01-01

    Systemic sclerosis (SSc) is an acquired multiorgan connective tissue disease with variable mortality and morbidity dictated by clinical subset type. The etiology of the basic disease and pathogenesis of the systemic autoimmunity, fibrosis, and fibroproliferative vasculopathy are unknown and debated. In this review, the spectrum of vascular abnormalities and the options currently available to treat the vascular manifestations of SSc are discussed. Also discussed is how the hallmark pathologies (ie, how autoimmunity, vasculopathy, and fibrosis of the disease) might be effected and interconnected with modulatory input from lysophospholipids, sphingosine 1-phosphate, and lysophosphatidic acid. PMID:22096374

  2. Nrf2/Keap1 system regulates vascular smooth muscle cell apoptosis for vascular homeostasis: role in neointimal formation after vascular injury

    PubMed Central

    Ashino, Takashi; Yamamoto, Masayuki; Numazawa, Satoshi

    2016-01-01

    Abnormal increases in vascular smooth muscle cells (VSMCs) in the intimal region after a vascular injury is a key event in developing neointimal hyperplasia. To maintain vascular function, proliferation and apoptosis of VSMCs is tightly controlled during vascular remodeling. NF-E2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1) system, a key component of the oxidative stress response that acts in maintaining homeostasis, plays an important role in neointimal hyperplasia after a vascular injury; however, the role of Nrf2/Keap1 in VSMC apoptosis has not been clarified. Here we report that 14 days after arterial injury in mice, TUNEL-positive VSMCs are detected in both the neointimal and medial layers. These layers contain cells expressing high levels of Nrf2 but low Keap1 expression. In VSMCs, Keap1 depletion induces features of apoptosis, such as positive TUNEL staining and annexin V binding. These changes are associated with an increased expression of nuclear Nrf2. Simultaneous Nrf2 depletion inhibits Keap1 depletion-induced apoptosis. At 14 days after the vascular injury, Nrf2-deficient mice demonstrated fewer TUNEL-positive cells and increased neointimal formation in the neointimal and medial areas. The results suggest that the Nrf2/Keap1 system regulates VSMC apoptosis during neointimal formation, thereby inhibiting neointimal hyperplasia after a vascular injury. PMID:27198574

  3. The skeletal vascular system - Breathing life into bone tissue.

    PubMed

    Stegen, Steve; Carmeliet, Geert

    2017-08-26

    During bone development, homeostasis and repair, a dense vascular system provides oxygen and nutrients to highly anabolic skeletal cells. Characteristic for the vascular system in bone is the serial organization of two capillary systems, each typified by specific morphological and physiological features. Especially the arterial capillaries mediate the growth of the bone vascular system, serve as a niche for skeletal and hematopoietic progenitors and couple angiogenesis to osteogenesis. Endothelial cells and osteoprogenitor cells interact not only physically, but also communicate to each other by secretion of growth factors. A vital angiogenic growth factor is vascular endothelial growth factor and its expression in skeletal cells is controlled by osteogenic transcription factors and hypoxia signaling, whereas the secretion of angiocrine factors by endothelial cells is regulated by Notch signaling, blood flow and possibly hypoxia. Bone loss and impaired fracture repair are often associated with reduced and disorganized blood vessel network and therapeutic targeting of the angiogenic response may contribute to enhanced bone regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Systemic Multiple Aneurysms Caused by Vascular Ehlers-Danlos Syndrome.

    PubMed

    Gui, Xinyu; Li, Fangda; Wu, Lingeer; Zheng, Yuehong

    2016-07-01

    Systemic multiple aneurysms are rare and usually associated with collagen tissue disease, such as Ehlers-Danlos syndrome (EDS) or Marfan syndrome. In the present case, we describe a 39-year-old male patient with systemic multiple aneurysms and acute intraperitoneal hemorrhage who was clinically diagnosed with vascular EDS. Coil embolization of the distal segment of the common hepatic artery was performed, which resolved the patient's symptoms. With this case presentation, we aim to increase the awareness of vascular EDS among clinicians and emphasize the extreme fragility of the arteries in patients with vascular EDS. © The Author(s) 2016.

  5. Guidance of vascular development: lessons from the nervous system.

    PubMed

    Larrivée, Bruno; Freitas, Catarina; Suchting, Steven; Brunet, Isabelle; Eichmann, Anne

    2009-02-27

    The vascular system of vertebrates consists of an organized, branched network of arteries, veins, and capillaries that penetrates all the tissues of the body. One of the most striking features of the vascular system is that its branching pattern is highly stereotyped, with major and secondary branches forming at specific sites and developing highly conserved organ-specific vascular patterns. The factors controlling vascular patterning are not yet completely understood. Recent studies have highlighted the anatomic and structural similarities between blood vessels and nerves. The 2 networks are often aligned, with nerve fibers and blood vessels following parallel routes. Furthermore, both systems require precise control over their guidance and growth. Several molecules with attractive and repulsive properties have been found to modulate the proper guidance of both nerves and blood vessels. These include the Semaphorins, the Slits, and the Netrins and their receptors. In this review, we describe the molecular mechanisms by which blood vessels and axons achieve proper path finding and the molecular cues that are involved in their guidance.

  6. Vascular Remodelling and Mesenchymal Transition in Systemic Sclerosis

    PubMed Central

    Nicolosi, Pier Andrea; Tombetti, Enrico; Maugeri, Norma; Rovere-Querini, Patrizia; Brunelli, Silvia; Manfredi, Angelo A.

    2016-01-01

    Fibrosis of the skin and of internal organs, autoimmunity, and vascular inflammation are hallmarks of Systemic Sclerosis (SSc). The injury and activation of endothelial cells, with hyperplasia of the intima and eventual obliteration of the vascular lumen, are early features of SSc. Reduced capillary blood flow coupled with deficient angiogenesis leads to chronic hypoxia and tissue ischemia, enforcing a positive feed-forward loop sustaining vascular remodelling, further exacerbated by extracellular matrix accumulation due to fibrosis. Despite numerous developments and a growing number of controlled clinical trials no treatment has been shown so far to alter SSc natural history, outlining the need of further investigation in the molecular pathways involved in the pathogenesis of the disease. We review some processes potentially involved in SSc vasculopathy, with attention to the possible effect of sustained vascular inflammation on the plasticity of vascular cells. Specifically we focus on mesenchymal transition, a key phenomenon in the cardiac and vascular development as well as in the remodelling of injured vessels. Recent work supports the role of transforming growth factor-beta, Wnt, and Notch signaling in these processes. Importantly, endothelial-mesenchymal transition may be reversible, possibly offering novel cues for treatment. PMID:27069480

  7. Vascular Anomalies (Part I): Classification and Diagnostics of Vascular Anomalies.

    PubMed

    Sadick, Maliha; Müller-Wille, René; Wildgruber, Moritz; Wohlgemuth, Walter A

    2018-06-06

    Vascular anomalies are a diagnostic and therapeutic challenge. They require dedicated interdisciplinary management. Optimal patient care relies on integral medical evaluation and a classification system established by experts in the field, to provide a better understanding of these complex vascular entities.  A dedicated classification system according to the International Society for the Study of Vascular Anomalies (ISSVA) and the German Interdisciplinary Society of Vascular Anomalies (DiGGefA) is presented. The vast spectrum of diagnostic modalities, ranging from ultrasound with color Doppler, conventional X-ray, CT with 4 D imaging and MRI as well as catheter angiography for appropriate assessment is discussed.  Congenital vascular anomalies are comprised of vascular tumors, based on endothelial cell proliferation and vascular malformations with underlying mesenchymal and angiogenetic disorder. Vascular tumors tend to regress with patient's age, vascular malformations increase in size and are subdivided into capillary, venous, lymphatic, arterio-venous and combined malformations, depending on their dominant vasculature. According to their appearance, venous malformations are the most common representative of vascular anomalies (70 %), followed by lymphatic malformations (12 %), arterio-venous malformations (8 %), combined malformation syndromes (6 %) and capillary malformations (4 %).  The aim is to provide an overview of the current classification system and diagnostic characterization of vascular anomalies in order to facilitate interdisciplinary management of vascular anomalies.   · Vascular anomalies are comprised of vascular tumors and vascular malformations, both considered to be rare diseases.. · Appropriate treatment depends on correct classification and diagnosis of vascular anomalies, which is based on established national and international classification systems, recommendations and guidelines.. · In the classification

  8. Vitamins E and C - effects on matrix components in the vascular system

    USDA-ARS?s Scientific Manuscript database

    The connective tissue in the vascular system, consisting mainly of vascular smooth muscle cells (VSMC) and the interstitial extracellular matrix (ECM), plays important roles in the maintenance of an intact vascular wall as well as in the repair of atherosclerotic lesions during disease development. ...

  9. Water vascular system architecture in an Ordovician ophiuroid.

    PubMed

    Clark, Elizabeth G; Bhullar, Bhart-Anjan S; Darroch, Simon A F; Briggs, Derek E G

    2017-12-01

    Understanding the water vascular system (WVS) in early fossil echinoderms is critical to elucidating the evolution of this system in extant forms. Here we present the first report of the internal morphology of the water vascular system of a stem ophiuroid. The radial canals are internal to the arm, but protected dorsally by a plate separate to the ambulacrals. The canals zig-zag with no evidence of constrictions, corresponding to sphincters, which control pairs of tube feet in extant ophiuroids. The morphology suggests that the unpaired tube feet must have operated individually, and relied on the elasticity of the radial canals, lateral valves and tube foot musculature alone for extension and retraction. This arrangement differs radically from that in extant ophiuroids, revealing a previously unknown Palaeozoic configuration. © 2017 The Author(s).

  10. Evolutionary origins of the blood vascular system and endothelium

    PubMed Central

    Monahan-Earley, Rita; Dvorak, Ann M.; Aird, William C.

    2017-01-01

    Every biological trait requires both a proximate and evolutionary explanation. The field of vascular biology is focused primarily on proximate mechanisms in health and disease. Comparatively little attention has been given to the evolutionary basis of the cardiovascular system. Here, we employ a comparative approach to review the phylogenetic history of the blood vascular system and endothelium. In addition to drawing on the published literature, we provide primary ultrastructural data related to the lobster, earthworm, amphioxus and hagfish. Existing evidence suggests that the blood vascular system first appeared in an ancestor of the triploblasts over 600 million years ago, as a means to overcome the time-distance constraints of diffusion. The endothelium evolved in an ancestral vertebrate some 540–510 million years ago to optimize flow dynamics and barrier function, and/or to localize immune and coagulation functions. Finally, we emphasize that endothelial heterogeneity evolved as a core feature of the endothelium from the outset, reflecting its role in meeting the diverse needs of body tissues. PMID:23809110

  11. Computer-aided design of microvasculature systems for use in vascular scaffold production.

    PubMed

    Mondy, William Lafayette; Cameron, Don; Timmermans, Jean-Pierre; De Clerck, Nora; Sasov, Alexander; Casteleyn, Christophe; Piegl, Les A

    2009-09-01

    In vitro biomedical engineering of intact, functional vascular networks, which include capillary structures, is a prerequisite for adequate vascular scaffold production. Capillary structures are necessary since they provide the elements and compounds for the growth, function and maintenance of 3D tissue structures. Computer-aided modeling of stereolithographic (STL) micro-computer tomographic (micro-CT) 3D models is a technique that enables us to mimic the design of vascular tree systems containing capillary beds, found in tissues. In our first paper (Mondy et al 2009 Tissue Eng. at press), using micro-CT, we studied the possibility of using vascular tissues to produce data capable of aiding the design of vascular tree scaffolding, which would help in the reverse engineering of a complete vascular tree system including capillary bed structures. In this paper, we used STL models of large datasets of computer-aided design (CAD) data of vascular structures which contained capillary structures that mimic those in the dermal layers of rabbit skin. Using CAD software we created from 3D STL models a bio-CAD design for the development of capillary-containing vascular tree scaffolding for skin. This method is designed to enhance a variety of therapeutic protocols including, but not limited to, organ and tissue repair, systemic disease mediation and cell/tissue transplantation therapy. Our successful approach to in vitro vasculogenesis will allow the bioengineering of various other types of 3D tissue structures, and as such greatly expands the potential applications of biomedical engineering technology into the fields of biomedical research and medicine.

  12. The influence of the telomere-telomerase system on diabetes mellitus and its vascular complications.

    PubMed

    Qi Nan, Wu; Ling, Zhang; Bing, Chen

    2015-06-01

    The telomere-telomerase system plays an important role in the pathogenesis and disease progression of diabetes mellitus as well as in its vascular complications. Recent studies suggest that telomere shortening and abnormal telomerase activity occur in patients with diabetes mellitus, and targeting the telomere-telomerase system has become a prospective treatment for diabetes mellitus and its vascular complications. This review highlights the significance of the telomere-telomerase system and supports its role as a possible therapeutic target for patients with diabetes mellitus and its vascular complications Areas covered: This review covers the advances in understanding the telomere-telomerase system over the last 30 years and its significance in diabetes mellitus. In addition, it provides knowledge regarding the significance of the telomere-telomerase system in diabetes mellitus and its vascular complications as well as its role and mechanisms in oxidative stress, cell therapy and antioxidant activity Expert opinion: The telomere-telomerase system may be a potential therapeutic target that can protect against DNA damage and apoptosis in patients with diabetes mellitus and its vascular complications. DNA damage and apoptosis are associated with oxidative stress and are involved in the dysfunction of pancreatic β cells, insulin resistance, and its vascular complications. Abnormalities in the telomere-telomerase system may be associated with diabetes mellitus and its vascular complications. Therapies targeting telomere-telomerase system, telomerase reverse transcriptase transfection and alterative telomere lengthening must be identified before gene therapy can commence.

  13. Evolution of the VEGF-regulated vascular network from a neural guidance system.

    PubMed

    Ponnambalam, Sreenivasan; Alberghina, Mario

    2011-06-01

    The vascular network is closely linked to the neural system, and an interdependence is displayed in healthy and in pathophysiological responses. How has close apposition of two such functionally different systems occurred? Here, we present a hypothesis for the evolution of the vascular network from an ancestral neural guidance system. Biological cornerstones of this hypothesis are the vascular endothelial growth factor (VEGF) protein family and cognate receptors. The primary sequences of such proteins are conserved from invertebrates, such as worms and flies that lack discernible vascular systems compared to mammals, but all these systems have sophisticated neuronal wiring involving such molecules. Ancestral VEGFs and receptors (VEGFRs) could have been used to develop and maintain the nervous system in primitive eukaryotes. During evolution, the demands of increased morphological complexity required systems for transporting molecules and cells, i.e., biological conductive tubes. We propose that the VEGF-VEGFR axis was subverted by evolution to mediate the formation of biological tubes necessary for transport of fluids, e.g., blood. Increasingly, there is evidence that aberrant VEGF-mediated responses are also linked to neuronal dysfunctions ranging from motor neuron disease, stroke, Parkinson's disease, Alzheimer's disease, ischemic brain disease, epilepsy, multiple sclerosis, and neuronal repair after injury, as well as common vascular diseases (e.g., retinal disease). Manipulation and correction of the VEGF response in different neural tissues could be an effective strategy to treat different neurological diseases.

  14. Genetic and epigenetic mechanisms in the early development of the vascular system

    PubMed Central

    Ribatti, Domenico

    2006-01-01

    The cardiovascular system plays a critical role in vertebrate development and homeostasis. Vascular development is a highly organized sequence of events that requires the correct spatial and temporal expression of specific sets of genes leading to the development of a primary vascular network. There have been intensive efforts to determine the molecular mechanisms regulating vascular growth and development, and much of the rationale for this has stemmed from the increasing clinical importance and therapeutic potential of modulating vascular formation during various disease states. PMID:16441559

  15. Vascular Hyperpermeability Response in Animals Systemically Exposed to Arsenic.

    PubMed

    Chen, Shih-Chieh; Chang, Chao-Yuah; Lin, Ming-Lu

    2018-01-01

    The mechanisms underlying cardiovascular diseases induced by chronic exposure to arsenic remain unclarified. The objectives of this study were to investigate whether increased vascular leakage is induced by inflammatory mustard oil in mice systemically exposed to various doses of arsenic and whether an increased vascular leakage response is still present in arsenic-fed mice after arsenic discontinuation for 2 or 6 months. ICR mice were fed water or various doses of sodium arsenite (10, 15, or 20 mg/kg/day; 5 days/week) for 8 weeks. In separate experiments, the mice were treated with sodium arsenite (20 mg/kg) for 2 or 8 weeks, followed by arsenic discontinuation for 2 or 6 months. Vascular permeability to inflammatory mustard oil was quantified using Evans blue (EB) techniques. Both arsenic-exposed and water-fed (control) mice displayed similar basal levels of EB leakage in the ears brushed with mineral oil, a vehicle of mustard oil. The levels of EB leakage induced by mustard oil in the arsenic groups fed with sodium arsenite (10 or 15 mg/kg) were similar to those of water-fed mice. However, increased levels of EB leakage in response to mustard oil stimulation were significantly higher in mice treated with sodium arsenite (20 mg/kg; high dose) than in arsenic-fed (10 or 15 mg/kg; low and middle doses) or control mice. After arsenic discontinuation for 2 or 6 months, mustard oil-induced vascular EB leakage in arsenic-fed (20 mg/kg) mice was similar to that in control mice. Dramatic increases in mustard oil-induced vascular leakage were only present in mice systemically exposed to the high arsenic dose, indicating the synergistic effects of the high arsenic dose and mustard oil.

  16. The plant vascular system: Evolution, development and functions

    USDA-ARS?s Scientific Manuscript database

    The emergence of the tracheophyte-based vascular system of land plants had major impacts on the evolution of terrestrial biology, in general, through its role in facilitating the development of plants with increased stature, photosynthetic output, and ability to colonize a greatly expanded range of ...

  17. Stroke from systemic vascular disorders in Saudi children. The devastating role of hypernatremic dehydration.

    PubMed

    Salih, Mustafa A; Zahraa, Jihad N; Al-Jarallah, Ahmed A; Alorainy, Ibrahim A; Hassan, Hamdy H

    2006-03-01

    Systemic vascular disorders, leading to childhood stroke, include volume depletion or systemic hypotension and hypernatremic dehydration. We describe 3 cases of stroke following systemic vascular disorders. These were diagnosed during a prospective and retrospective study on childhood stroke, which included 104 patients. Post-gastroenteritis hypernatremic dehydration is an important, potentially preventable, cause of stroke in Saudi children.

  18. Vascular system modeling in parallel environment - distributed and shared memory approaches

    PubMed Central

    Jurczuk, Krzysztof; Kretowski, Marek; Bezy-Wendling, Johanne

    2011-01-01

    The paper presents two approaches in parallel modeling of vascular system development in internal organs. In the first approach, new parts of tissue are distributed among processors and each processor is responsible for perfusing its assigned parts of tissue to all vascular trees. Communication between processors is accomplished by passing messages and therefore this algorithm is perfectly suited for distributed memory architectures. The second approach is designed for shared memory machines. It parallelizes the perfusion process during which individual processing units perform calculations concerning different vascular trees. The experimental results, performed on a computing cluster and multi-core machines, show that both algorithms provide a significant speedup. PMID:21550891

  19. VASCULAR PLANTS AS ENGINEERS OF OXYGEN IN AQUATIC SYSTEMS

    EPA Science Inventory

    The impact of organisms on oxygen is one of the most dramatic examples of ecosystem engineering on Earth. In aquatic systems, which have much lower oxygen concentrations than the atmosphere, vascular aquatic plants can affect oxygen concentrations significantly not only on long t...

  20. Vascular pattern formation in plants.

    PubMed

    Scarpella, Enrico; Helariutta, Ykä

    2010-01-01

    Reticulate tissue systems exist in most multicellular organisms, and the principles underlying the formation of cellular networks have fascinated philosophers, mathematicians, and biologists for centuries. In particular, the beautiful and varied arrangements of vascular tissues in plants have intrigued mankind since antiquity, yet the organizing signals have remained elusive. Plant vascular tissues form systems of interconnected cell files throughout the plant body. Vascular cells are aligned with one another along continuous lines, and vascular tissues differentiate at reproducible positions within organ environments. However, neither the precise path of vascular differentiation nor the exact geometry of vascular networks is fixed or immutable. Several recent advances converge to reconcile the seemingly conflicting predictability and plasticity of vascular tissue patterns. A control mechanism in which an apical-basal flow of signal establishes a basic coordinate system for body axis formation and vascular strand differentiation, and in which a superimposed level of radial organizing cues elaborates cell patterns, would generate a reproducible tissue configuration in the context of an underlying robust, self-organizing structure, and account for the simultaneous regularity and flexibility of vascular tissue patterns. Copyright 2010 Elsevier Inc. All rights reserved.

  1. Eduardo Primo Yúfera, founder of Revista de Agroquímica y Tecnología de Alimentos and pioneer on food science and technology research in Spain.

    PubMed

    Ayala-Gascón, M; Aleixandre-Benavent, R; Gandía-Balaguer, A

    2011-12-01

    Eduardo Primo Yúfera was the founder and director of the Instituto de Agroquímica y Tecnología de Alimentos (IATA, 1957-1974) until he was appointed president of the Consejo Superior de Investigaciones Científicas (CSIC). His aim to publicize food science led him to create the Revista de Agroquímica y Tecnología de Alimentos in 1961, the forerunner of this journal, Food Science and Technology International, which he directed until 1977. Of his scientific output, 50% has been published in this journal. He is considered to be the promoter and exponent of Food Science and Technology and Chemical Ecology in Spain as well as the instigator of the country's innovation model (R&D and innovation). In his work, he was able to combine basic research excellence and socially relevant applied research to move both science and society forward. He was an example and inspiration to many colleagues and followers. The aim of this study is to highlight the influence and importance of Primo Yúfera in the formation, development and consolidation of the journal Revista de Agroquímica y Tecnología de Alimentos, and to appraise his scientific contribution to this journal.

  2. RGB imaging system for monitoring of skin vascular malformation's laser therapy

    NASA Astrophysics Data System (ADS)

    Jakovels, Dainis; Kuzmina, Ilona; Berzina, Anna; Spigulis, Janis

    2012-06-01

    A prototype RGB imaging system for mapping of skin chromophores consists of a commercial RGB CMOS sensor, RGB LEDs ring-light illuminator and orthogonally orientated polarizers for reducing specular reflectance. The system was used for monitoring of vascular malformations (hemagiomas and telangiectasias) therapy.

  3. Nitric oxide signaling and the cross talk with prostanoids pathways in vascular system.

    PubMed

    Silva, Bruno R; Paula, Tiago D; Paulo, Michele; Bendhack, Lusiane M

    2016-12-28

    This review provides an overview of the cellular signaling of nitric oxide (NO) and prostanoids in vascular cells and the possible cross talk between their pathways, mainly in hypertension, since the imbalance of these two systems has been attributed to development of some cardiovascular diseases. It also deals with the modulation of vasodilation induced by NO donors. NO is a well-known second messenger involved in many cellular functions. In the vascular system, the NO produced by endothelial NO-synthase (eNOS) or released by NO donors acts in vascular smooth muscle cells, the binding of NO to Fe2+-heme of soluble guanylyl-cyclase (sGC) activates sGC and the production of cyclic guanosine-3-5-monophosphate (cGMP). The second messenger (cGMP) activates protein kinase G and the signaling cascade, including K+ channels. Activation of K+ channels leads to cell membrane hyperpolarization and Ca2+ channels blockade, which induce vascular relaxation. Moreover, the enzyme cyclooxygenase (COX) is also an important regulator of the vascular function by prostanoids production such as thromboxane A2 (TXA2) and prostacyclin (PGI2), which classically induce contraction and relaxation, respectively. Additionaly, studies indicate that the activity of both enzymes can be modulated by their products and reactive oxygen species (ROS) in cardiovascular diseases such as hypertension. The interaction of NO with cellular molecules, particularly the reaction of NO with ROS, determines the biological mechanisms of action and short half-life of NO. We have been working on the vascular effects of ruthenium-derived complexes that release NO. Our research group has published works on the vasodilating effects of ruthenium-derived NO donors and the mechanisms of vascular cells involved in the relaxation of the vascular smooth muscle in health and hypertensive rats. In our previous studies, we have compared the new NO donors synthesized by our group to SNP. It shows the cellular signaling of NO

  4. The plant vascular system: Evolution, development and functions

    Treesearch

    William J. Lucas; Andrew Groover; Raffael Lichtenberger; Kaori Furuta; Shri-Ram Yadav; Yka Helariutta; Xin-Qiang He; Hiroo Fukuda; Julie Kang; Siobhan M. Brady; John W. Patrick; John Sperry; Akiko Yoshida; Ana-Flor Lopez-Millan; Michael A. Grusak; Pradeep Kachroo

    2013-01-01

    The emergence of the tracheophyte-based vascular system of land plants had major impacts on the evolution of terrestrial biology, in general, through its role in facilitating the development of plants with increased stature, photosynthetic output, and ability to colonize a greatly expanded range of environmental habitats. Recently, considerable progress has been made...

  5. Toll-like Receptors in the Vascular System: Sensing the Dangers Within

    PubMed Central

    McCarthy, Cameron G.; Webb, R. Clinton

    2016-01-01

    Toll-like receptors (TLRs) are components of the innate immune system that respond to exogenous infectious ligands (pathogen-associated molecular patterns, PAMPs) and endogenous molecules that are released during host tissue injury/death (damage-associated molecular patterns, DAMPs). Interaction of TLRs with their ligands leads to activation of downstream signaling pathways that induce an immune response by producing inflammatory cytokines, type I interferons (IFN), and other inflammatory mediators. TLR activation affects vascular function and remodeling, and these molecular events prime antigen-specific adaptive immune responses. Despite the presence of TLRs in vascular cells, the exact mechanisms whereby TLR signaling affects the function of vascular tissues are largely unknown. Cardiovascular diseases are considered chronic inflammatory conditions, and accumulating data show that TLRs and the innate immune system play a determinant role in the initiation and development of cardiovascular diseases. This evidence unfolds a possibility that targeting TLRs and the innate immune system may be a novel therapeutic goal for these conditions. TLR inhibitors and agonists are already in clinical trials for inflammatory conditions such as asthma, cancer, and autoimmune diseases, but their study in the context of cardiovascular diseases is in its infancy. In this article, we review the current knowledge of TLR signaling in the cardiovascular system with an emphasis on atherosclerosis, hypertension, and cerebrovascular injury. Furthermore, we address the therapeutic potential of TLR as pharmacological targets in cardiovascular disease and consider intriguing research questions for future study. PMID:26721702

  6. [Aspects of vascular physiology in clinical and vascular surgical practice: basic principles of vascular mechanics].

    PubMed

    Nocke, H; Meyer, F; Lessmann, V

    2014-10-01

    To be able to evaluate properly a vascular problem, basic concepts of vascular physiology need to be considered, as they have been taught in physiology for a long time. This article deals with selected definitions and laws of passive vascular mechanics, subdivided into parameters of vascular filling and parameters of vascular flow. PARAMETERS OF VASCULAR FILLING: During vascular filling the transmural pressure distends the vascular wall until it is balanced by the wall tension. The extent of this distension up to the point of balance depends on the elasticity of the wall. Transmural pressure, wall tension and elasticity are defined, and their respective importance is described by clinical examples, e.g. aneurysm and varix. PARAMETERS OF VASCULAR FLOW: The vascular flow can be divided into stationary and pulsating components. Both components are relevant for the bloodstream. Since the blood flow is directed in the circuit, it can be understood in first approximation as stationary ("direct current").The direct current model uses only the average values of the pulsating variables. The great advantage of the direct current model is that it can be described with simple laws, which are not valid without reservation, but often allow a first theoretical approach to a vascular problem: Ohm's law, driving pressure, flow resistance, Hagen-Poiseuille law, wall shear stress, law of continuity, Bernoulli's equation and Reynold's number are described and associated with clinical examples.The heart is a pressure-suction pump and produces a pulsating flow, the pulse. The pulse runs with pulse wave velocity, which is much larger than the blood flow velocity, through the arterial vascular system. During propagation, the pulse has to overcome the wave resistance (impedance). Wherever the wave resistance changes, e.g., at vascular bifurcations and in the periphery, it comes to reflections. The incident (forward) and reflected (backward) waves are superimposed to yield the resulting

  7. A consonant construction of the hyaloid and retinal vascular systems by the angiogenic process.

    PubMed

    Gergely, K; Gerinec, A

    2011-01-01

    There has been much debate as to whether the retinal vasculature forms by angiogenesis or vasculogenesis, thus angiogenesis is now accepted. We suppose that signals necessary for proper localization and development of the hyaloid and retinal vascular systems are already in place prior to the time at which these systems are developed. The remarkable conservation of vascular patterning suggests that specific genetic programs coordinate its formation. Evidence for a genetic program comes particularly from the characterization of gene-targeted mice and mutational analysis in zebrafish, but the exact genetic pathways remain poorly defined. Considering all the things from the aspect of angiogenesis significant differences exist between the mentioned vascular systems only in their lifetime (a) and location (b): (a) The hyaloid vasculature is a complex of transient intraocular vessels, while the retinal vessels are adapted for the whole life. (b) The hyaloid system fills the interior of the optic cup and this way "occupies" three-dimensional space while the distribution of the retinal vessels is relatively planar (two-dimensional) in the retina. We assume that retinal vessels are "built" in the same manner as the hyaloid vasculature and the outcomes at the embryological, histological, cellular and molecular levels confirm it. We show a consonant construction of both systems. The human organism does not have any rational reason to build up one system (i.e. the hyaloid vasculature) by angiogenesis and practically the same system (i.e. the retinal vessels) by another, de novo process, in the eye. It would be a waste of energy and various essential molecules. Thus, it seems that the retinal vascular system is an advanced copy of the hyaloid vessels (Tab. 1, Ref. 143).

  8. The Renin-Angiotensin-Aldosterone System in Vascular Inflammation and Remodeling

    PubMed Central

    Pacurari, Maricica; Kafoury, Ramzi; Tchounwou, Paul B.; Ndebele, Kenneth

    2014-01-01

    The RAAS through its physiological effectors plays a key role in promoting and maintaining inflammation. Inflammation is an important mechanism in the development and progression of CVD such as hypertension and atherosclerosis. In addition to its main role in regulating blood pressure and its role in hypertension, RAAS has proinflammatory and profibrotic effects at cellular and molecular levels. Blocking RAAS provides beneficial effects for the treatment of cardiovascular and renal diseases. Evidence shows that inhibition of RAAS positively influences vascular remodeling thus improving CVD outcomes. The beneficial vascular effects of RAAS inhibition are likely due to decreasing vascular inflammation, oxidative stress, endothelial dysfunction, and positive effects on regeneration of endothelial progenitor cells. Inflammatory factors such as ICAM-1, VCAM-1, TNFα, IL-6, and CRP have key roles in mediating vascular inflammation and blocking RAAS negatively modulates the levels of these inflammatory molecules. Some of these inflammatory markers are clinically associated with CVD events. More studies are required to establish long-term effects of RAAS inhibition on vascular inflammation, vascular cells regeneration, and CVD clinical outcomes. This review presents important information on RAAS's role on vascular inflammation, vascular cells responses to RAAS, and inhibition of RAAS signaling in the context of vascular inflammation, vascular remodeling, and vascular inflammation-associated CVD. Nevertheless, the review also equates the need to rethink and rediscover new RAAS inhibitors. PMID:24804145

  9. ADULT WITH CHICKENPOX COMPLICATED BY SYSTEMIC VASCULITIS AND BILATERAL RETINAL VASCULITIS WITH RETINAL VASCULAR OCCLUSIONS.

    PubMed

    Murdock, Jennifer; Carvounis, Petros E

    2017-01-01

    To describe an adult with chickenpox resulting in systemic vasculitis and bilateral retinal vascular occlusions. Single case report. A 58-year-old man with chickenpox complicated by disseminated varicella-zoster systemic and retinal vasculitis resulting in a combined arterial and venous occlusion in one eye with multiple branch retinal vein occlusions in the other eye. There was no evidence of retinitis. The patient systemically improved after treatment with acyclovir and steroids; however, his vision remained poor. Chickenpox can be associated with systemic vasculopathy and may rarely result in multiple systemic and ocular infarcts, including severe retinal vascular occlusions.

  10. [The age-related macular degeneration as a vascular disease/part of systemic vasculopathy: contributions to its pathogenesis].

    PubMed

    Fischer, Tamás

    2015-03-01

    The wall of blood vessels including those in choroids may be harmed by several repeated and/or prolonged mechanical, physical, chemical, microbiological, immunologic, and genetic impacts (risk factors), which may trigger a protracted response, the so-called host defense response. As a consequence, pathological changes resulting in vascular injury (e. g. atherosclerosis, age-related macular degeneration) may be evolved. Risk factors can also act directly on the endothelium through an increased production of reactive oxygen species promoting an endothelial activation, which leads to endothelial dysfunction, the onset of vascular disease. Thus, endothelial dysfunction is a link between the harmful stimulus and vascular injury; any kind of harmful stimuli may trigger the defensive chain that results in inflammation that may lead to vascular injury. It has been shown that even early age-related macular degeneration is associated with the presence of diffuse arterial disease and patients with early age-related macular degeneration demonstrate signs of systemic and retinal vascular alterations. Chronic inflammation, a feature of AMD, is tightly linked to diseases associated with ED: AMD is accompanied by a general inflammatory response, in the form of complement system activation, similar to that observed in degenerative vascular diseases such as atherosclerosis. All these facts indicate that age-related macular degeneration may be a vascular disease (or part of a systemic vasculopathy). This recognition could have therapeutic implications because restoration of endothelial dysfunction may prevent the development or improve vascular disease resulting in prevention or improvement of age-related macular degeneration as well.

  11. The vascular endothelium in diabetes--a therapeutic target?

    PubMed

    Mather, Kieren J

    2013-03-01

    Insulin resistance affects the vascular endothelium, and contributes to systemic insulin resistance by directly impairing the actions of insulin to redistribute blood flow as part of its normal actions driving muscle glucose uptake. Impaired vascular function is a component of the insulin resistance syndrome, and is a feature of type 2 diabetes. On this basis, the vascular endothelium has emerged as a therapeutic target where the intent is to improve systemic metabolic state by improving vascular function. We review the available literature presenting studies in humans, evaluating the effects of metabolically targeted and vascular targeted therapies on insulin action and systemic metabolism. Therapies that improve systemic insulin resistance exert strong concurrent effects to improve vascular function and vascular insulin action. RAS-acting agents and statins have widely recognized beneficial effects on vascular function but have not uniformly produced the hoped-for metabolic benefits. These observations support the notion that systemic metabolic benefits can arise from therapies targeted at the endothelium, but improving vascular insulin action does not result from all treatments that improve endothelium-dependent vasodilation. A better understanding of the mechanisms of insulin's actions in the vascular wall will advance our understanding of the specificity of these responses, and allow us to better target the vasculature for metabolic benefits.

  12. Evolutionary morphology of the hemolymph vascular system of basal araneomorph spiders (Araneae: Araneomorphae).

    PubMed

    Huckstorf, Katarina; Michalik, Peter; Ramírez, Martín; Wirkner, Christian S

    2015-11-01

    The superfamily Austrochiloidea (Austrochilidae and Gradungulidae) take a pivotal position in araneomorph spider phylogeny. In this discussion crevice weaver spiders (Filistatidae) are of equal interest. Especially data from these phylogenetically uncertain yet basal off branching groups can enlighten our understanding on the evolution of organ systems. In the course of a survey on the evolutionary morphology of the circulatory system in spiders we therefore investigated the hemolymph vascular system in two austrochiloid and one filistatid species. Additionally some data on a hypochilid and a gradungulid species are included. Using up-to-date morphological methods, the vascular systems in these spiders are visualized three dimensionally. Ground pattern features of the circulatory systems in austrochiloid spiders are presented and the data discussed along recent lines of phylogenetic hypotheses. Special topics highlighted are the intraspecific variability of the origins of some prosomal arteries and the evolutionary correlation of respiratory and circulatory systems in spiders. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Combined flaps based on the superficial temporal vascular system for reconstruction of facial defects.

    PubMed

    Zhou, Renpeng; Wang, Chen; Qian, Yunliang; Wang, Danru

    2015-09-01

    Facial defects are multicomponent deficiencies rather than simple soft-tissue defects. Based on different branches of the superficial temporal vascular system, various tissue components can be obtained to reconstruct facial defects individually. From January 2004 to December 2013, 31 patients underwent reconstruction of facial defects with composite flaps based on the superficial temporal vascular system. Twenty cases of nasal defects were repaired with skin and cartilage components, six cases of facial defects were treated with double island flaps of the skin and fascia, three patients underwent eyebrow and lower eyelid reconstruction with hairy and hairless flaps simultaneously, and two patients underwent soft-tissue repair with auricular combined flaps and cranial bone grafts. All flaps survived completely. Donor-site morbidity is minimal, closed primarily. Donor areas healed with acceptable cosmetic results. The final outcome was satisfactory. Combined flaps based on the superficial temporal vascular system are a useful and versatile option in facial soft-tissue reconstruction. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  14. NASAs VESGEN: Systems Analysis of Vascular Phenotypes from Stress and Other Signaling Pathways Using GeneLab.

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia A.; Weitzel, Alexander; Vyas, Ruchi J.; Murray, Matthew C.; Wyatt, Sarah E.

    2016-01-01

    One fundamental requirement shared by humans with all higher terrestrial life forms, including insect wings, higher land plants and other vertebrates, is a complex, fractally branching vascular system. NASA's VESsel GENeration Analysis (VESGEN) software maps and quantifies vascular trees, networks, and tree-network composites according to weighted physiological rules such as vessel connectivity, tapering and bifurcational branching. According to fluid dynamics, successful vascular transport requires a complex distributed system of highly regulated laminar flow. Microvascular branching rules within vertebrates, dicot leaves and the other organisms therefore display many similarities. One unifying perspective is that vascular patterning offers a useful readout that necessarily integrates complex molecular signaling pathways. VESGEN has elucidated changes in vascular pattern resulting from inflammatory, stress response, developmental and other signaling within numerous tissues and major model organisms studied for Space Biology. For a new VESGEN systems approach, we analyzed differential gene expression in leaves of Arabidopsis thaliana reported by GeneLab (GLDS-7) for spaceflight. Vascular-related changes in leaf gene expression were identified that can potentially be phenocopied by mutants in ground-based experiments. To link transcriptional, protein and other molecular change with phenotype, alterations in the Euclidean and dynamic dimensions (x,y,t) of vascular patterns for Arabidopsis leaves and other model species are being co-localized with signaling patterns of single molecular expression analyzed as information dimensions (i,j,k,...). Previously, Drosophila microarray data returned from space suggested significant changes in genes related to wing venation development that include EGF, Notch, Hedghog, Wingless and Dpp signaling. Phenotypes of increasingly abnormal ectopic wing venation in the (non-spaceflight) Drosophila wing generated by overexpression of a

  15. The challenge of establishing treatment efficacy for cutaneous vascular manifestations of systemic sclerosis.

    PubMed

    Pauling, John D

    2018-05-01

    The cutaneous vascular manifestations of systemic sclerosis (SSc) comprise Raynaud's phenomenon, cutaneous ulceration, telangiectasia formation and critical digital ischaemia; each of which are associated with significant disease-related morbidity. Despite the availability of multiple classes of vasodilator therapy, many of which have been the subject of RCTs, a limited number of pharmacological interventions are currently approved for the management of cutaneous vascular manifestations of SSc. Areas covered: A major challenge has been demonstrating treatment efficacy with examples of promising therapies yielding contrasting results in controlled trial settings. Differences between consensus best-practice guidelines, evidence-based recommendations and marketing approvals in different jurisdictions has resulted in geographic variation in clinical practice concerning the management of cutaneous vascular manifestations of SSc. Difficulty demonstrating treatment efficacy risks waning industry engagement for drug development programmes in this field. This article highlights the key challenges in establishing treatment efficacy and barriers that must be overcome to support successful clinical trial programmes across the spectrum of cutaneous vascular manifestations of SSc. Expert commentary: The paucity of approved treatments for cutaneous vascular manifestations of SSc relates as much to challenges in clinical trial design and the need for reliable clinical trial endpoints, as to lack of therapeutic options.

  16. An assembly-type master-slave catheter and guidewire driving system for vascular intervention.

    PubMed

    Cha, Hyo-Jeong; Yi, Byung-Ju; Won, Jong Yun

    2017-01-01

    Current vascular intervention inevitably exposes a large amount of X-ray to both an operator and a patient during the procedure. The purpose of this study is to propose a new catheter driving system which assists the operator in aspects of less X-ray exposure and convenient user interface. For this, an assembly-type 4-degree-of-freedom master-slave system was designed and tested to verify the efficiency. First, current vascular intervention procedures are analyzed to develop a new robotic procedure that enables us to use conventional vascular intervention devices such as catheter and guidewire which are commercially available in the market. Some parts of the slave robot which contact the devices were designed to be easily assembled and dissembled from the main body of the slave robot for sterilization. A master robot is compactly designed to conduct insertion and rotational motion and is able to switch from the guidewire driving mode to the catheter driving mode or vice versa. A phantom resembling the human arteries was developed, and the master-slave robotic system is tested using the phantom. The contact force of the guidewire tip according to the shape of the arteries is measured and reflected to the user through the master robot during the phantom experiment. This system can drastically reduce radiation exposure by replacing human effort by a robotic system for high radiation exposure procedures. Also, benefits of the proposed robot system are low cost by employing currently available devices and easy human interface.

  17. Vascular Access System for Continuous Arterial Infusion of a Protease Inhibitor in Acute Necrotizing Pancreatitis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ganaha, Fumikiyo; Yamada, Tetsuhisa; Yorozu, Naoya

    1999-09-15

    We used a vascular access system (VAS) for continuous arterial infusion (CAI) of a protease inhibitor in two patients with acute necrotizing pancreatitis. The infusion catheter was placed into the dorsal pancreatic artery in the first patient and into the gastroduodenal artery in the second, via a femoral artery approach. An implantable port was then connected to the catheter and was secured in a subcutaneous pocket prepared in the right lower abdomen. No complications related to the VAS were encountered. This system provided safe and uncontaminated vascular access for successful CAI for acute pancreatitis.

  18. Vascular Cell Induction Culture System Using Arabidopsis Leaves (VISUAL) Reveals the Sequential Differentiation of Sieve Element-Like Cells.

    PubMed

    Kondo, Yuki; Nurani, Alif Meem; Saito, Chieko; Ichihashi, Yasunori; Saito, Masato; Yamazaki, Kyoko; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Fukuda, Hiroo

    2016-06-01

    Cell differentiation is a complex process involving multiple steps, from initial cell fate specification to final differentiation. Procambial/cambial cells, which act as vascular stem cells, differentiate into both xylem and phloem cells during vascular development. Recent studies have identified regulatory cascades for xylem differentiation. However, the molecular mechanism underlying phloem differentiation is largely unexplored due to technical challenges. Here, we established an ectopic induction system for phloem differentiation named Vascular Cell Induction Culture System Using Arabidopsis Leaves (VISUAL). Our results verified similarities between VISUAL-induced Arabidopsis thaliana phloem cells and in vivo sieve elements. We performed network analysis using transcriptome data with VISUAL to dissect the processes underlying phloem differentiation, eventually identifying a factor involved in the regulation of the master transcription factor gene APL Thus, our culture system opens up new avenues not only for genetic studies of phloem differentiation, but also for future investigations of multidirectional differentiation from vascular stem cells. © 2016 American Society of Plant Biologists. All rights reserved.

  19. [Malignant vascular tumors of the vulva].

    PubMed

    Chokoeva, A; Tchernev, G

    2015-01-01

    Due to the increased vascularity as well as the unique anatomical structure, vascular lesions, which occur in the female reproductive system are common observed and diverse by their morphology. The majority of them are benign, including vascular malformations, lesions due to vascular hyperplasia, tumors with significant vascular component and others. Malignant vascular tumors are rare in the area of the vulva accounting about 1% of all vulvar lesions with vascular origin. Kaposi sarcoma, epithelioid hemangioepithelioma and epithelioid angiosarcoma have been reported with vulvar localization. With a view to their rare incidence, nonspecific clinical manifestation and aggressive behavior associated with high mortality, we present the most common malignant tumors of vascular origin arising in the vulva, as we emphasize on their epidemiology and clinical features, differential diagnosis and therapeutic algorithms for this rare type of malignancies.

  20. [Vascular dental anaesthesias and their mechanism].

    PubMed

    Petrikas, A Zh; Iakupova, L A; Medvedev, A V; Borodina, O E; Egorova, V A; Diuba

    2010-01-01

    By their mechanism of action local anaesthesia methods were divided into diffused and vascular. Intraosseous, intraseptal and intraligamental anesthaesias are vascular ones at capillary-venous system level. Circulatory mechanism besides effectiveness increased more than 2-fold and also promotes enhancement of cardiovascular system responses.

  1. Peripheral vascular tumors and vascular malformations: imaging (magnetic resonance imaging and conventional angiography), pathologic correlation and treatment options.

    PubMed

    El-Merhi, Fadi; Garg, Deepak; Cura, Marco; Ghaith, Ola

    2013-02-01

    Vascular anomalies are classified into vascular tumors (infantile hemangioma) and vascular malformations. Vascular malformations are divided into slow flow and high flow subtypes. Magnetic resonance imaging helps in classification and assessing extent and distribution. Conventional angiography also known as digital subtraction angiography is pivotal in assessment of fine vascular details and treatment planning. Imaging correlates well with histopathology. We review recent development in imaging techniques of various vascular anomalies most of which are affecting the peripheral system which potentially may broaden understanding of their diagnosis, classification and treatment.

  2. Peripheral vascular damage in systemic lupus erythematosus: data from LUMINA, a large multi-ethnic U.S. cohort (LXIX).

    PubMed

    Burgos, P I; Vilá, L M; Reveille, J D; Alarcón, G S

    2009-12-01

    To determine the factors associated with peripheral vascular damage in systemic lupus erythematosus patients and its impact on survival from Lupus in Minorities, Nature versus Nurture, a longitudinal US multi-ethnic cohort. Peripheral vascular damage was defined by the Systemic Lupus International Collaborating Clinics Damage Index (SDI). Factors associated with peripheral vascular damage were examined by univariable and multi-variable logistic regression models and its impact on survival by a Cox multi-variable regression. Thirty-four (5.3%) of 637 patients (90% women, mean [SD] age 36.5 [12.6] [16-87] years) developed peripheral vascular damage. Age and the SDI (without peripheral vascular damage) were statistically significant (odds ratio [OR] = 1.05, 95% confidence interval [CI] 1.01-1.08; P = 0.0107 and OR = 1.30, 95% CI 0.09-1.56; P = 0.0043, respectively) in multi-variable analyses. Azathioprine, warfarin and statins were also statistically significant, and glucocorticoid use was borderline statistically significant (OR = 1.03, 95% CI 0.10-1.06; P = 0.0975). In the survival analysis, peripheral vascular damage was independently associated with a diminished survival (hazard ratio = 2.36; 95% CI 1.07-5.19; P = 0.0334). In short, age was independently associated with peripheral vascular damage, but so was the presence of damage in other organs (ocular, neuropsychiatric, renal, cardiovascular, pulmonary, musculoskeletal and integument) and some medications (probably reflecting more severe disease). Peripheral vascular damage also negatively affected survival.

  3. Human vascular renin-angiotensin system and its functional changes in relation to different sodium intakes.

    PubMed

    Boddi, M; Poggesi, L; Coppo, M; Zarone, N; Sacchi, S; Tania, C; Neri Serneri, G G

    1998-03-01

    A growing body of evidence supports the existence of a tissue-based renin-angiotensin system (RAS) in the vasculature, but the functional capacity of vascular RAS was not investigated in humans. In 28 normotensive healthy control subjects, the metabolism of angiotensins through vascular tissue was investigated in normal, low, and high sodium diets by the measurement of arterial-venous gradient of endogenous angiotensin (Ang) I and Ang II in two different vascular beds (forearm and leg), combined with the study of 125I-Ang I and 125I-Ang II kinetics. In normal sodium diet subjects, forearm vascular tissue extracted 36+/-6% of 125I-Ang I and 30+/-5% of 125I-Ang II and added 14.9+/-5.1 fmol x 100 mL(-1) x min(-1) of de novo formed Ang I and 6.2+/-2.8 fmol x 100 mL(-1) x min(-1) of Ang II to antecubital venous blood. Fractional conversion of 125I-Ang I through forearm vascular tissue was about 12%. Low sodium diet increased (P<.01) plasma renin activity, whereas de novo Ang I and Ang II formation by forearm vascular tissue became undetectable. Angiotensin degradation (33+/-7% for Ang I and 30+/-7% for Ang II) was unchanged, and vascular fractional conversion of 125I-Ang I decreased from 12% to 6% (P<.01). In high sodium diet subjects, plasma renin activity decreased, and de novo Ang I and Ang II formation by forearm vascular tissue increased to 22 and 14 fmol x 100 mL(-1) x min(-1), respectively (P<.01). Angiotensin degradation did not significantly change, whereas fractional conversion of 125I-Ang I increased from 12% to 20% (P<.01). Leg vascular tissue functional activities of RAS paralleled those of forearm vascular tissue both at baseline and during different sodium intake. These results provide consistent evidence for the existence of a functional tissue-based RAS in vascular tissue of humans. The opposite changes of plasma renin activity and vascular angiotensin formation indicate that vascular RAS is independent from but related to circulating RAS.

  4. Vascular malformations: an update.

    PubMed

    Gloviczki, Peter; Duncan, Audra; Kalra, Manju; Oderich, Gustavo; Ricotta, Joseph; Bower, Thomas; McKusick, Michael; Bjarnason, Haraldur; Driscoll, David

    2009-06-01

    Vascular malformations occur as a result of an arrest in the development of the vascular system. The modified Hamburg classification distinguishes arterial, venous, arteriovenous, capillary, lymphatic, and mixed vascular malformations. Each malformation is further subdivided based on anatomy and on the time when arrest in development of the embryogenesis occurred; malformations can be truncular or extratruncular. Progress in the last decade in management has been significant because of improvements in open surgical procedures and perfection of percutaneous and hybrid endovascular interventions and devices, such as balloons, stents, and stent-grafts. There has been increasing use of embolization for the treatment of malformations with coils, other particles, glue, or with endovascular placement of occlusive plugs. Absolute alcohol, detergent liquids, or foam have been used for sclerotherapy with improved efficacy. The agents are delivered percutaneously or through a catheter placed either into the feeding arteries or the draining veins. This review aims to aid vascular and endovascular specialists in staying familiar with vascular malformations. These specialists need to be able to evaluate the patients, perform treatment if appropriate, or refer complex cases to multidisciplinary vascular malformation clinics and vascular centers.

  5. Oxidative airway inflammation leads to systemic and vascular oxidative stress in a murine model of allergic asthma.

    PubMed

    Al-Harbi, Naif O; Nadeem, A; Al-Harbi, Mohamed M; Imam, F; Al-Shabanah, Othman A; Ahmad, Sheikh F; Sayed-Ahmed, Mohamed M; Bahashwan, Saleh A

    2015-05-01

    Oxidant-antioxidant imbalance plays an important role in repeated cycles of airway inflammation observed in asthma. It is when reactive oxygen species (ROS) overwhelm antioxidant defenses that a severe inflammatory state becomes apparent and may impact vasculature. Several studies have shown an association between airway inflammation and cardiovascular complications; however so far none has investigated the link between airway oxidative stress and systemic/vascular oxidative stress in a murine model of asthma. Therefore, this study investigated the contribution of oxidative stress encountered in asthmatic airways in modulation of vascular/systemic oxidant-antioxidant balance. Rats were sensitized intraperitoneally with ovalbumin (OVA) in the presence of aluminum hydroxide followed by several intranasal (i.n.) challenges with OVA. Rats were then assessed for airway and vascular inflammation, oxidative stress (ROS, lipid peroxides) and antioxidants measured as total antioxidant capacity (TAC) and thiol content. Challenge with OVA led to increased airway inflammation and oxidative stress with a concomitant increase in vascular inflammation and oxidative stress. Oxidative stress in the vasculature was significantly inhibited by antioxidant treatment, N-acetyl cysteine; whereas hydrogen peroxide (H2O2) inhalation worsened it. Therefore, our study shows that oxidative airway inflammation is associated with vascular/systemic oxidative stress which might predispose these patients to increased cardiovascular risk. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. 3D printed biomimetic vascular phantoms for assessment of hyperspectral imaging systems

    NASA Astrophysics Data System (ADS)

    Wang, Jianting; Ghassemi, Pejhman; Melchiorri, Anthony; Ramella-Roman, Jessica; Mathews, Scott A.; Coburn, James; Sorg, Brian; Chen, Yu; Pfefer, Joshua

    2015-03-01

    The emerging technique of three-dimensional (3D) printing provides a revolutionary way to fabricate objects with biologically realistic geometries. Previously we have performed optical and morphological characterization of basic 3D printed tissue-simulating phantoms and found them suitable for use in evaluating biophotonic imaging systems. In this study we assess the potential for printing phantoms with irregular, image-defined vascular networks that can be used to provide clinically-relevant insights into device performance. A previously acquired fundus camera image of the human retina was segmented, embedded into a 3D matrix, edited to incorporate the tubular shape of vessels and converted into a digital format suitable for printing. A polymer with biologically realistic optical properties was identified by spectrophotometer measurements of several commercially available samples. Phantoms were printed with the retinal vascular network reproduced as ~1.0 mm diameter channels at a range of depths up to ~3 mm. The morphology of the printed vessels was verified by volumetric imaging with μ-CT. Channels were filled with hemoglobin solutions at controlled oxygenation levels, and the phantoms were imaged by a near-infrared hyperspectral reflectance imaging system. The effect of vessel depth on hemoglobin saturation estimates was studied. Additionally, a phantom incorporating the vascular network at two depths was printed and filled with hemoglobin solution at two different saturation levels. Overall, results indicated that 3D printed phantoms are useful for assessing biophotonic system performance and have the potential to form the basis of clinically-relevant standardized test methods for assessment of medical imaging modalities.

  7. The role of robotic surgical system in the management of vascular disease.

    PubMed

    Lin, Judith C

    2013-10-01

    The evolution of minimally invasive treatment for aneurysms and occlusive disease has led to the development of endovascular, laparoscopic, and robot-assisted techniques. This article reviews the current literature on the clinical use of robotic surgical systems in the treatment of patients with aneurysms and occlusive disease. A MEDLINE search was performed using the keywords "robotic, vascular, AND surgery." All pertinent articles concerning the use of the robotic surgical system on aneurysms and occlusive disease were reviewed. The author's personal experience consisted of a retrospective review of a prospectively maintained confidential database on all procedures performed with the da Vinci(®) surgical system. Several robot-assisted laparoscopic series on the treatment of aortic disease were identified, including review articles of potential clinical applications in hybrid, laparoscopic vascular, and endovascular treatments for vascular patients using robotic technology. The use of computer-enhanced or robotic technology as a sole modality for bypass of occlusive disease and repair of abdominal aortic, splenic, and renal aneurysms was described in case series with satisfactory patient outcomes. Current robotic endovascular technology was also described. Minimally invasive techniques using endovascular, laparoscopic, or robot-assisted technology have revolutionized the treatment of aortoiliac, splanchnic, and renal aneurysms and occlusive disease. However, robot-assisted techniques for aortic disease may involve a learning curve and increased operating times. Although endovascular therapy is preferred because of faster recovery, this preference for improved short-term outcomes will be balanced with the superiority and durability of robot-assisted endoscopic methods as comparable to open surgery. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Amplatzer vascular plug as an embolic agent in different vascular pathologies: A pictorial essay

    PubMed Central

    Tresley, Jonathan; Bhatia, Shivank; Kably, Issam; Poozhikunnath Mohan, Prasoon; Salsamendi, Jason; Narayanan, Govindarajan

    2016-01-01

    The Amplatzer Vascular Plug (AVP) is a cylindrical plug made of self-expanding nitinol wire mesh with precise delivery control, which can be used for a variety of vascular pathologies. An AVP is an ideal vascular occlusion device particularly in high-flow vessels, where there is high risk of migration and systemic embolization with traditional occlusion devices. We performed 28 embolizations using the AVP from 2009 to 2014 and achieved complete occlusion without complications. PMID:27413276

  9. Vascular determinants of cholinergic deficits in Alzheimer disease and vascular dementia.

    PubMed

    Román, Gustavo C; Kalaria, Raj N

    2006-12-01

    Alzheimer's disease (AD) and vascular dementia (VaD) are widely accepted as the most common forms of dementia. Cerebrovascular lesions frequently coexist with AD, creating an overlap in the clinical and pathological features of VaD and AD. This review assembles evidence for a role for cholinergic mechanisms in the pathogenesis of VaD, as has been established for AD. We first consider the anatomy and vascularization of the basal forebrain cholinergic neuronal system, emphasizing its susceptibility to the effects of arterial hypertension, sustained hypoperfusion, and ischemic cerebrovascular disease. The impact of aging and consequences of disruption of the cholinergic system in cognition and in control of cerebral blood flow are further discussed. We also summarize preclinical and clinical evidence supporting cholinergic deficits and the use of cholinesterase inhibitors in patients with VaD. We postulate that vascular pathology likely plays a common role in initiating cholinergic neuronal abnormalities in VaD and AD.

  10. Proangiogenic hematopoietic cells of monocytic origin: roles in vascular regeneration and pathogenic processes of systemic sclerosis.

    PubMed

    Yamaguchi, Yukie; Kuwana, Masataka

    2013-02-01

    New blood vessel formation is critical, not only for organ development and tissue regeneration, but also for various pathologic processes, such as tumor development and vasculopathy. The maintenance of the postnatal vascular system requires constant remodeling, which occurs through angiogenesis, vasculogenesis, and arteriogenesis. Vasculogenesis is mediated by the de novo differentiation of mature endothelial cells from endothelial progenitor cells (EPCs). Early studies provided evidence that bone marrow-derived CD14⁺ monocytes can serve as a subset of EPCs because of their expression of endothelial markers and ability to promote neovascularization in vitro and in vivo. However, the current consensus is that monocytic cells do not give rise to endothelial cells in vivo, but function as support cells, by promoting vascular formation and repair through their immediate recruitment to the site of vascular injury, secretion of proangiogenic factors, and differentiation into mural cells. These monocytes that function in a supporting role in vascular repair are now termed monocytic pro-angiogenic hematopoietic cells (PHCs). Systemic sclerosis (SSc) is a multisystem connective tissue disease characterized by excessive fibrosis and microvasculopathy, along with poor vascular formation and repair. We recently showed that in patients with SSc, circulating monocytic PHCs increase dramatically and have enhanced angiogenic potency. These effects may be induced in response to defective vascular repair machinery. Since CD14⁺ monocytes can also differentiate into fibroblast-like cells that produce extracellular matrix proteins, here we propose a new hypothesis that aberrant monocytic PHCs, once mobilized into circulation, may also contribute to the fibrotic process of SSc.

  11. Vascular lumen formation.

    PubMed

    Lammert, Eckhard; Axnick, Jennifer

    2012-04-01

    The vascular system developed early in evolution. It is required in large multicellular organisms for the transport of nutrients, oxygen, and waste products to and from tissues. The vascular system is composed of hollow tubes, which have a high level of complexity in vertebrates. Vasculogenesis describes the de novo formation of blood vessels, e.g., aorta formation in vertebrate embryogenesis. In contrast, angiogenesis is the formation of blood vessels from preexisting ones, e.g., sprouting of intersomitic blood vessels from the aorta. Importantly, the lumen of all blood vessels in vertebrates is lined and formed by endothelial cells. In both vasculogenesis and angiogenesis, lumen formation takes place in a cord of endothelial cells. It involves a complex molecular mechanism composed of endothelial cell repulsion at the cell-cell contacts within the endothelial cell cords, junctional rearrangement, and endothelial cell shape change. As the vascular system also participates in the course of many diseases, such as cancer, stroke, and myocardial infarction, it is important to understand and make use of the molecular mechanisms of blood vessel formation to better understand and manipulate the pathomechanisms involved.

  12. In vitro vascularization of a combined system based on a 3D printing technique.

    PubMed

    Zhao, Xinru; Liu, Libiao; Wang, Jiayin; Xu, Yufan; Zhang, Weiming; Khang, Gilson; Wang, Xiaohong

    2016-10-01

    A vital challenge in complex organ manufacturing is to vascularize large combined tissues. The aim of this study is to vascularize in vitro an adipose-derived stem cell (ADSC)/fibrin/collagen incorporated three-dimensional (3D) poly(d,l-lactic-co-glycolic acid) (PLGA) scaffold (10 × 10 × 10 mm 3 ) with interconnected channels. A low-temperature 3D printing technique was employed to build the PLGA scaffold. A step-by-step cocktail procedure was designed to engage or steer the ADSCs in the PLGA channels towards both endothelial and smooth muscle cell lineages. The combined system had sufficient mechanical properties to support the cell/fibrin/collagen hydrogel inside the predefined PLGA channels. The ADSCs encapsulated in the fibrin/collagen hydrogel differentiated to endothelial and smooth muscle cell lineage, respectively, corresponding to their respective locations in the construct and formed vascular-like structures. This technique allows in vitro vascularization of the predefined PLGA channels and provides a choice for complex organ manufacture. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Complex nonlinear autonomic nervous system modulation link cardiac autonomic neuropathy and peripheral vascular disease.

    PubMed

    Khalaf, Kinda; Jelinek, Herbert F; Robinson, Caroline; Cornforth, David J; Tarvainen, Mika P; Al-Aubaidy, Hayder

    2015-01-01

    Physiological interactions are abundant within, and between, body systems. These interactions may evolve into discrete states during pathophysiological processes resulting from common mechanisms. An association between arterial stenosis, identified by low ankle-brachial pressure index (ABPI) and cardiovascular disease (CVD) as been reported. Whether an association between vascular calcification-characterized by high ABPI and a different pathophysiology-is similarly associated with CVD, has not been established. The current study aims to investigate the association between ABPI, and cardiac rhythm, as an indicator of cardiovascular health and functionality, utilizing heart rate variability (HRV). Two hundred and thirty six patients underwent ABPI assessment. Standard time and frequency domain, and non-linear HRV measures were determined from 5-min electrocardiogram. ABPI data were divided into normal (n = 101), low (n = 67) and high (n = 66) and compared to HRV measures.(DFAα1 and SampEn were significantly different between the low ABPI, high ABPI and control groups (p < 0.05). A possible coupling between arterial stenosis and vascular calcification with decreased and increased HRV respectively was observed. Our results suggest a model for interpreting the relationship between vascular pathophysiology and cardiac rhythm. The cardiovascular system may be viewed as a complex system comprising a number of interacting subsystems. These cardiac and vascular subsystems/networks may be coupled and undergo transitions in response to internal or external perturbations. From a clinical perspective, the significantly increased sample entropy compared to the normal ABPI group and the decreased and increased complex correlation properties measured by DFA for the low and high ABPI groups respectively, may be useful indicators that a more holistic treatment approach in line with this more complex clinical picture is required.

  14. Scanning electron microscopic study on the microarchitecture of the vascular system in the pigeon lung.

    PubMed

    Nasu, Tetsuo

    2005-10-01

    The resin casts of the respiratory and vascular systems in pigeon lung were examined using a scanning electron microscope. The primary bronchi branched to form many secondary bronchi that anastomosed with each other via the parabronchi. Numerous infundibula protruded from the parabronchi via the atria and ramified into the air capillaries. The pulmonary artery entered into the lung and branched into three vessels that coursed the interparabronchial parts. The intraparabronchial arterioles penetrated the gas-exchange tissue to form the anastomosing networks of blood capillaries. The observation of the double casts of the respiratory and vascular systems revealed three-dimensional complicated networks of air capillaries and blood capillaries.

  15. Bioprinting for vascular and vascularized tissue biofabrication.

    PubMed

    Datta, Pallab; Ayan, Bugra; Ozbolat, Ibrahim T

    2017-03-15

    Bioprinting is a promising technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision. Bioprinting enables the deposition of various biologics including growth factors, cells, genes, neo-tissues and extra-cellular matrix-like hydrogels. Benefits of bioprinting have started to make a mark in the fields of tissue engineering, regenerative medicine and pharmaceutics. Specifically, in the field of tissue engineering, the creation of vascularized tissue constructs has remained a principal challenge till date. However, given the myriad advantages over other biofabrication methods, it becomes organic to expect that bioprinting can provide a viable solution for the vascularization problem, and facilitate the clinical translation of tissue engineered constructs. This article provides a comprehensive account of bioprinting of vascular and vascularized tissue constructs. The review is structured as introducing the scope of bioprinting in tissue engineering applications, key vascular anatomical features and then a thorough coverage of 3D bioprinting using extrusion-, droplet- and laser-based bioprinting for fabrication of vascular tissue constructs. The review then provides the reader with the use of bioprinting for obtaining thick vascularized tissues using sacrificial bioink materials. Current challenges are discussed, a comparative evaluation of different bioprinting modalities is presented and future prospects are provided to the reader. Biofabrication of living tissues and organs at the clinically-relevant volumes vitally depends on the integration of vascular network. Despite the great progress in traditional biofabrication approaches, building perfusable hierarchical vascular network is a major challenge. Bioprinting is an emerging technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision

  16. Systemic vascular load in calcific degenerative aortic valve stenosis: insight from percutaneous valve replacement.

    PubMed

    Yotti, Raquel; Bermejo, Javier; Gutiérrez-Ibañes, Enrique; Pérez del Villar, Candelas; Mombiela, Teresa; Elízaga, Jaime; Benito, Yolanda; González-Mansilla, Ana; Barrio, Alicia; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Fernández-Avilés, Francisco

    2015-02-10

    Systemic arterial load impacts the symptomatic status and outcome of patients with calcific degenerative aortic stenosis (AS). However, assessing vascular properties is challenging because the arterial tree's behavior could be influenced by the valvular obstruction. This study sought to characterize the interaction between valvular and vascular functions in patients with AS by using transcatheter aortic valve replacement (TAVR) as a clinical model of isolated intervention. Aortic pressure and flow were measured simultaneously using high-fidelity sensors in 23 patients (mean 79 ± 7 years of age) before and after TAVR. Blood pressure and clinical response were registered at 6-month follow-up. Systolic and pulse arterial pressures, as well as indices of vascular function (vascular resistance, aortic input impedance, compliance, and arterial elastance), were significantly modified by TAVR, exhibiting stiffer vascular behavior post-intervention (all, p < 0.05). Peak left ventricular pressure decreased after TAVR (186 ± 36 mm Hg vs. 162 ± 23 mm Hg, respectively; p = 0.003) but remained at >140 mm Hg in 70% of patients. Wave intensity analysis showed abnormally low forward and backward compression waves at baseline, increasing significantly after TAVR. Stroke volume decreased (-21 ± 19%; p < 0.001) and correlated with continuous and pulsatile indices of arterial load. In the 48 h following TAVR, a hypertensive response was observed in 12 patients (52%), and after 6-month follow-up, 5 patients required further intensification of discharge antihypertensive therapy. Vascular function in calcific degenerative AS is conditioned by the upstream valvular obstruction that dampens forward and backward compression waves in the arterial tree. An increase in vascular load after TAVR limits the procedure's acute afterload relief. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  17. A case of vascular Ehlers-Danlos Syndrome with a cardiomyopathy and multi-system involvement.

    PubMed

    Lan, Nick Si Rui; Fietz, Michael; Pachter, Nicholas; Paul, Vincent; Playford, David

    Ehlers-Danlos Syndrome comprises a heterogeneous group of heritable connective tissue disorders resulting from various gene mutations. We present an unusual case of vascular Ehlers-Danlos Syndrome with distinctive physical characteristics and a cardiomyopathy with features suggesting isolated left ventricular non-compaction. The cardiac features represent the first report of a cardiomyopathy associated with a mutation in the COL3A1 gene. This case also illustrates the multi-system nature of Ehlers-Danlos Syndrome and the complexity of managing patients with the vascular subtype. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Using NASA's GeneLab for VESGEN Systems Analysis of Vascular Phenotypes from Stress and Other Signaling Pathways

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, P.; Weitzel, Alexander; Vyas, R. J.; Murray, M. C.; Vickerman, M. B.; Bhattacharya, S.; Wyatt, S. E.

    2016-01-01

    One fundamental requirement shared by humans with all higher terrestrial life forms, including other vertebrates, insects, and higher land plants, is a complex, fractally branching vascular system. NASA's VESsel GENeration Analysis (VESGEN) software maps and quantifies vascular trees, networks, and tree-network composites according to weighted physiological rules such as vessel connectivity, tapering and bifurcational branching. According to fluid dynamics, successful vascular transport requires a complex distributed system of highly regulated laminar flow. Microvascular branching rules within vertebrates, dicot leaves and the other organisms therefore display many similarities. A unifying perspective is that vascular patterning offers a useful readout of molecular signaling that necessarily integrates these complex pathways. VESGEN has elucidated changes in vascular pattern resulting from inflammatory, developmental and other signaling within numerous tissues and major model organisms studied for Space Biology. For a new VESGEN systems approach, we analyzed differential gene expression in leaves of Arabidopsis thaliana reported by GeneLab (GLDS-7) for spaceflight. Vascularrelated changes in leaf gene expression were identified that can potentially be phenocopied by mutants in ground-based experiments. To link transcriptional, protein and other molecular change with phenotype, alterations in the spatial and dynamic dimensions of vascular patterns for Arabidopsis leaves and other model species are being co-localized with signaling patterns of single molecular expression analyzed as information dimensions. Previously, Drosophila microarray data returned from space suggested significant changes in genes related to wing venation development that include EGF, Notch, Hedghog, Wingless and Dpp signaling. Phenotypes of increasingly abnormal ectopic wing venation in the (non-spaceflight) Drosophila wing generated by overexpression of a Notch antagonist were analyzed by

  19. Using biplanar fluoroscopy to guide radiopaque vascular injections: a new method for vascular imaging.

    PubMed

    O'Brien, Haley D; Williams, Susan H

    2014-01-01

    Studying vascular anatomy, especially in the context of relationships with hard tissues, is of great interest to biologists. Vascular studies have provided significant insight into physiology, function, phylogenetic relationships, and evolutionary patterns. Injection of resin or latex into the vascular system has been a standard technique for decades. There has been a recent surge in popularity of more modern methods, especially radiopaque latex vascular injection followed by CT scanning and digital "dissection." This technique best displays both blood vessels and bone, and allows injections to be performed on cadaveric specimens. Vascular injection is risky, however, because it is not a standardizable technique, as each specimen is variable with regard to injection pressure and timing. Moreover, it is not possible to view the perfusion of injection medium throughout the vascular system of interest. Both data and rare specimens can therefore be lost due to poor or excessive perfusion. Here, we use biplanar video fluoroscopy as a technique to guide craniovascular radiopaque latex injection. Cadaveric domestic pigs (Sus scrofa domestica) and white-tailed deer (Odocoileus virginianus) were injected with radiopaque latex under guidance of fluoroscopy. This method was found to enable adjustments, in real-time, to the rate, location, and pressure at which latex is injected in order to avoid data and specimen loss. In addition to visualizing the injection process, this technique can be used to determine flow patterns, and has facilitated the development of consistent markers for complete perfusion.

  20. Vascular retraction driven by matrix softening

    NASA Astrophysics Data System (ADS)

    Valentine, Megan

    We recently discovered we can directly apply physical forces and monitor the downstream responses in a living organism in real time through manipulation of the blood vessels of a marine organism called, Botryllus schlosseri. The extracellular matrix (ECM) plays a key role in regulating vascular growth and homeostasis in Botryllus,a basal chordate which has a large, transparent extracorporeal vascular network that can encompass areas >100 cm2. We have determined that lysyl oxidase 1 (LOX1), which is responsible for cross-linking collagen, is expressed in all vascular cells and is critically important for vascular maintenance. Inhibition of LOX1 activity in vivo by the addition of a specific inhibitor, ß-aminopropionitrile (BAPN), caused a rapid, global regression of the entire vascular bed, with some vessels regressing >10 mm within 16 hrs. In this talk, I will discuss the molecular and cellular origins of this systemic remodeling event, which hinges upon the ability of the vascular cells to sense and respond to mechanical signals, while introducing this exciting new model system for studies of biological physics and mechanobiology. Collaborators: Anthony DeTomaso, Delany Rodriguez, Aimal Khankhel (UCSB).

  1. In Vitro Endothelialization of Biodegradable Vascular Grafts Via Endothelial Progenitor Cell Seeding and Maturation in a Tubular Perfusion System Bioreactor.

    PubMed

    Melchiorri, Anthony J; Bracaglia, Laura G; Kimerer, Lucas K; Hibino, Narutoshi; Fisher, John P

    2016-07-01

    A critical challenge to the success of biodegradable vascular grafts is the establishment of a healthy endothelium. To establish this monolayer of endothelial cells (ECs), a variety of techniques have been developed, including cell seeding. Vascular grafts may be seeded with relevant cell types and allowed to mature before implantation. Due to the low proliferative ability of adult ECs and issues with donor site morbidity, there has been increasing interest in using endothelial progenitor cells (EPCs) for vascular healing procedures. In this work, we combined the proliferative and differentiation capabilities of a commercial cell line of early EPCs with an established bioreactor system to support the maturation of cell-seeded vascular grafts. All components of the vascular graft and bioreactor setup are commercially available and allow for complete customization of the scaffold and culturing system. This bioreactor setup enables the control of flow through the graft, imparting fluid shear stress on EPCs and affecting cellular proliferation and differentiation. Grafts cultured with EPCs in the bioreactor system demonstrated greatly increased cell populations and neotissue formation compared with grafts seeded and cultured in a static system. Increased expression of markers for mature endothelial tissues were also observed in bioreactor-cultured EPC-seeded grafts. These findings suggest the distinct advantages of a customizable bioreactor setup for the proliferation and maturation of EPCs. Such a strategy may be beneficial for utilizing EPCs in vascular tissue engineering applications.

  2. Does vascular stapling improve compliance of vascular anastomoses?

    PubMed

    Stansby, G; Knez, P; Berwanger, C S; Nelson, K; Reichert, V; Schmitz-Rixen, T

    2001-01-01

    Elastic properties of vessel walls are altered by vascular anastomoses. Such alterations may lead to neointimal hyperplasia, which is a common cause of reocclusion following vascular surgery. The severity of paraanastomotic hypercompliant zones and anastomotic compliance drop depend on suturing material and on elastic properties of the anastomotic vessel segments. This study compares paraanastomotic hypercompliance and anastomotic compliance drop when using a new vascular closure system (VCS) and a conventional, continuous suture line in the preparation of end-to-end anastomoses. Compliance of artery-artery, vein-artery, and polytetrafluoroethylene-artery anastomoses was measured in an artificial circulation system at mean pressures of 60, 90, and 120 mm Hg, comparing conventional suturing and the VCS. When using the VCS for vein-artery anastomoses, significantly less postanastomotic hypercompliance was achieved at mean pressures of 60 mm Hg (14.2 +/-3.8% above remote postanastomotic area), compared to suture (55.1 +/-14.8%, p<0.05). At 90 mm Hg, respective values were 11.0 +/-2.3% for VCS and 54.7 +/-10.1% for suture, p<0.01. At 120 mm Hg, in polytetrafluoroethylene-artery anastomoses, the anastomotic compliance drop was significantly less when using the continuous suture line (93.9 +/-1.1% below remote postanastomotic compliance), compared to VCS (97.2 +/-0.2%, p<0.05). Compared to conventional suturing, use of the VCS reduced postanastomotic hypercompliance in vein-artery anastomoses.

  3. Impact of a Discovery System on Interlibrary Loan

    ERIC Educational Resources Information Center

    Musser, Linda R.; Coopey, Barbara M.

    2016-01-01

    Web-scale discovery services such as Summon (Serial Solutions), WorldCat Local (OCLC), EDS (EBSCO), and Primo (Ex Libris) are often touted as a single search solution to connect users to library-owned and -licensed content, improving discoverability and retrieval of resources. Assessing how well these systems achieve this goal can be challenging,…

  4. Reduced contribution of endothelin to the regulation of systemic and pulmonary vascular tone in severe familial hypercholesterolaemia

    PubMed Central

    Bender, Shawn B; de Beer, Vincent J; Tharp, Darla L; van Deel, Elza D; Bowles, Douglas K; Duncker, Dirk J; Laughlin, M Harold; Merkus, Daphne

    2014-01-01

    Vascular dysfunction has been associated with familial hypercholesterolaemia (FH), a severe form of hyperlipidaemia. We recently demonstrated that swine with FH exhibit reduced exercise-induced systemic, but not pulmonary, vasodilatation involving reduced nitric oxide (NO) bioavailability. Since NO normally limits endothelin (ET) action, we examined the hypothesis that reduced systemic vasodilatation during exercise in FH swine results from increased ET-mediated vasoconstriction. Systemic and pulmonary vascular responses to exercise were examined in chronically instrumented normal and FH swine in the absence and presence of the ETA/B receptor antagonist tezosentan. Intrinsic reactivity to ET was further assessed in skeletal muscle arterioles. FH swine exhibited ∼9-fold elevation in total plasma cholesterol versus normal swine. Similar to our recent findings, systemic, not pulmonary, vasodilatation during exercise was reduced in FH swine. Blockade of ET receptors caused marked systemic vasodilatation at rest and during exercise in normal swine that was significantly reduced in FH swine. The reduced role of ET in FH swine in vivo was not the result of decreased arteriolar ET responsiveness, as responsiveness was increased in isolated arterioles. Smooth muscle ET receptor protein content was unaltered by FH. However, circulating plasma ET levels were reduced in FH swine. ET receptor antagonism caused pulmonary vasodilatation at rest and during exercise in normal, but not FH, swine. Therefore, contrary to our hypothesis, FH swine exhibit a generalised reduction in the role of ET in regulating vascular tone in vivo probably resulting from reduced ET production. This may represent a unique vascular consequence of severe familial hypercholesterolaemia. PMID:24421352

  5. [Vascularization of the head and neck during development].

    PubMed

    Detrait, E; Etchevers, H C

    2005-06-01

    One of the earliest priorities of the embryonic vascular system is to ensure the metabolic needs of the head. This review covers some of the principles that govern the cellular assembly and localization of blood vessels in the head. In order to understand the development and organization of the cephalic vascular tree, one needs to recall the morphogenetic movements underlying vertebrate head formation and giving rise to the constituent cells of the vascular system. Some of the major signaling molecules involved in vascular development are discussed, including the angiopoietins, the endothelins, the FGFs, the Notch receptors, the PDGFs, Sonic hedgehog, the TGF family and the VEGFs, in order to underline similarities between embryonic and postnatal vascular development, even in the context of increasingly divergent form.

  6. Light and Dark of Reactive Oxygen Species for Vascular Function: 2014 ASVB (Asian Society of Vascular Biology).

    PubMed

    Shimokawa, Hiroaki; Satoh, Kimio

    2015-05-01

    Vascular-derived hydrogen peroxide (H2O2) serves as an important signaling molecule in the cardiovascular system and contributes to vascular homeostasis. H2O2 is a second messenger, transducing the oxidative signal into biological responses through posttranslational protein modification. The balance between oxidant and antioxidant systems regulates intracellular redox status, and their imbalance causes oxidative or reductive stress, leading to cellular damage in cardiovascular systems. Excessive H2O2 deteriorates vascular functions and promotes vascular disease through multiple pathways. The RhoA/Rho-kinase pathway plays an important role in various fundamental cellular functions, including production of excessive reactive oxygen species, leading to the development of cardiovascular diseases. Rho-kinase (ROCK1 and ROCK2) belongs to the family of serine/threonine kinases and is an important downstream effector of the small GTP-binding protein RhoA. Rho-kinase plays a crucial role in the pathogenesis of vasospasm, arteriosclerosis, ischemia/reperfusion injury, hypertension, pulmonary hypertension, stroke, and heart failure. Thus, Rho-kinase inhibitors may be useful for the treatment of cardiovascular diseases in humans. In this review, we will briefly discuss the roles of vascular-derived H2O2 and review the recent progress in the translational research on the therapeutic importance of the Rho-kinase pathway in cardiovascular medicine.

  7. Exercise training and cardiometabolic diseases: focus on the vascular system.

    PubMed

    Roque, Fernanda R; Hernanz, Raquel; Salaices, Mercedes; Briones, Ana M

    2013-06-01

    The regular practice of physical activity is a well-recommended strategy for the prevention and treatment of several cardiovascular and metabolic diseases. Physical exercise prevents the progression of vascular diseases and reduces cardiovascular morbidity and mortality. Exercise training also ameliorates vascular changes including endothelial dysfunction and arterial remodeling and stiffness, usually present in type 2 diabetes, obesity, hypertension and metabolic syndrome. Common to these diseases is excessive oxidative stress, which plays an important role in the processes underlying vascular changes. At the vascular level, exercise training improves the redox state and consequently NO availability. Moreover, growing evidence indicates that other mediators such as prostanoids might be involved in the beneficial effects of exercise. The purpose of this review is to update recent findings describing the adaptation response induced by exercise in cardiovascular and metabolic diseases, focusing more specifically on the beneficial effects of exercise in the vasculature and the underlying mechanisms.

  8. The lymphatic vascular system of the mouse head.

    PubMed

    Lohrberg, Melanie; Wilting, Jörg

    2016-12-01

    Histological studies of the lymphatic vascular system in adult mice are hampered because bones cannot be sectioned properly. Here, we decalcified the heads of 14-day-old mice, embedded them in paraffin and stained resultant serial sections with the lymphendothelial-specific antibodies Lyve-1 and Podoplanin. We show that the tissues with the highest lymphatic vascular density are the dermis and the oral mucous membranes. In contrast, the nasal mucous membrane is devoid of lymphatics, except for its most basal parts below the vomeronasal organ. The inferior nasal turbinate contains numerous lymphatics and is connected to the nasolacrimal duct (NLD), which is ensheathed by a dense network of lymphatics. The lymphatics of the eye lids and conjunctiva are connected to those of the inferior nasal turbinate. We suggest that cerebro-spinal fluid (CSF) can drain via the optic nerve and NLD lymphatics, whereas CSF drained via the Fila olfactoria into the nasal mucous membrane is used for moisturization of the respiratory air. Tongue, palatine and buccal mucous membranes possess numerous lymphatics, whereas the dental pulp has none. Lymphatics are present in the maxillary gland and close to the temporomandibular joint, suggesting the augmentation of lymph flow by chewing and yawning. Lymphatics can also be found in the dura mater and in the dural septae entering into deeper parts of the brain. Our findings are discussed with regard to CSF drainage and potential routes for ocular tumor dissemination.

  9. Histology atlas of the developing mouse hepatobiliary hemolymphatic vascular system with emphasis on embryonic days 11.5-18.5 and early postnatal development

    USDA-ARS?s Scientific Manuscript database

    A critical event in fetal development is the proper formation of the vascular system, of which the hepatobiliary system plays a pivotal role. This has lead pathologists and scientists to utilize transgenic mice to identify developmental disorders associated with the hepatobiliary vascular system. Va...

  10. Towards organ printing: engineering an intra-organ branched vascular tree.

    PubMed

    Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

    2010-03-01

    Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a 'built in' intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a 'built in' intra-organ branched vascular tree.

  11. Predictive value of vascular disease biomarkers for digital ulcers in systemic sclerosis patients.

    PubMed

    Silva, Ivone; Teixeira, Andreia; Oliveira, José; Almeida, Isabel; Almeida, Rui; Vasconcelos, Carlos

    2015-01-01

    To investigate the role of endothelial dysfunction and angiogenesis vascular biomarkers as risk factors and their predictive value for digital ulcers in systemic sclerosis patients. Endothelin-1 (ET-1), asymmetric dimethylarginine (ADMA), vascular endothelial growth factor (VEGF), endostatin and endoglin were measured in an observational prospective cohort of 77 SSc patients. The primary outcome was the occurrence of one or more new ischaemic digital ulcers during a planned 3-year follow-up. After the 3-year follow-up, 40 patients developed new digital ulcers. Logistic regression confirmed VEGF (HR 1.128, 95% CI 1.010-1.260, p=0.033) and ADMA (HR 0.995, 95% CI 0.991-0.998, p=0.006) as independent predictors of new digital ulcers. Patients with serum levels of ET-1>11.9 pmol/ml (p<0.001) and VEGF<422.47 pg/ml (p=0.028) had significantly more DU in the 3-year follow-up. Although not significant, a trend towards increased serum levels of endoglin>4.215 ng/ml (p=0.053) was associated to a new DU episode. No predictive serum value was found for ADMA (p=0.075) and endostatin (p=0.130). Endothelial dysfunction and angiogenic vascular biomarkers have an important role in the underlying and in the progression of microvascular disease in systemic sclerosis. Increased serum levels of ET-1, ADMA and VEGF are strong predictors of severe microangiopathy complications, namely ischaemic digital ulcers.

  12. Protecting against vascular disease in brain

    PubMed Central

    2011-01-01

    Endothelial cells exert an enormous influence on blood vessels throughout the circulation, but their impact is particularly pronounced in the brain. New concepts have emerged recently regarding the role of this cell type and mechanisms that contribute to endothelial dysfunction and vascular disease. Activation of the renin-angiotensin system plays a prominent role in producing these abnormalities. Both oxidative stress and local inflammation are key mechanisms that underlie vascular disease of diverse etiology. Endogenous mechanisms of vascular protection are also present, including antioxidants, anti-inflammatory molecules, and peroxisome proliferator-activated receptor-γ. Despite their clear importance, studies of mechanisms that underlie cerebrovascular disease continue to lag behind studies of vascular biology in general. Identification of endogenous molecules and pathways that protect the vasculature may result in targeted approaches to prevent or slow the progression of vascular disease that causes stroke and contributes to the vascular component of dementia and Alzheimer's disease. PMID:21335467

  13. Atherosclerotic vascular disease in systemic lupus erythematosus.

    PubMed

    Liang, Matthew H; Mandl, Lisa A; Costenbader, Karen; Fox, Ervin; Karlson, Elizabeth

    2002-09-01

    In the United States, systemic lupus erythematosus (SLE) disproportionately affects African Americans. It has become a chronic disease with long-term morbidity including chronic renal disease, osteoporosis, cataracts, psychosocial impairment, and importantly, atherosclerotic vascular disease (ASVD). The latter (myocardial infarction, angina, peripheral vascular disease and stroke) are strikingly accelerated, occurring in subjects who are predominantly premenopausal women at an age when ASVD is rare or unusual. Although much is known about the biology, risk factors, and the prevention of atherosclerosis in normal individuals, little work has been done in SLE. In fact, ASVD in people with SLE may be a different disease. Approximately 1.5% of SLE patients per year will have a myocardial infarction or equivalent; about 0.5% of SLE patients per year will have a stroke. The risk factors for ASVD in SLE are based on small, retrospective, single center studies. These suggest that the risk factors known for the general population (i.e., smoking, obesity, sedentary lifestyle, high LDL cholesterol, etc.) are also observed in SLE. The best study of risk factors shows that even accounting for the known factors, SLE and/or its treatment (glucocorticoids) is by far the most important. Our current management of cardiovascular risk factors in SLE patients with ASVD is substandard and our adherence to national guidelines for prevention is substandard. It is not known whether improving either will prevent these disastrous outcomes. Very little is known about the risk factors in African Americans with SLE, although there is data to suggest that they may not be identical to those seen in Caucasian populations. The study of the best and most effective means to prevent ASVD in SLE and in African Americans with SLE and in African Americans with SLE should be a major priority.

  14. From pregnancy to cardiovascular disease: lessons from relaxin-deficient animals to understanding relaxin actions in the vascular system.

    PubMed

    Jelinic, Maria; Marshall, Sarah A; Leo, Chen Huei; Parry, Laura J; Tare, Marianne

    2018-06-07

    Early maternal vascular adaptations to pregnancy are predominantly driven by changes in vascular tone, reactivity and remodelling. Failure of the maternal systemic vasculature to adapt sufficiently can lead to serious complications of pregnancy. The hormone relaxin is widely recognised for its contribution to the essential renal and systemic haemodynamic adaptations in early pregnancy through direct actions on the maternal vasculature. Studies in relaxin gene knockout mice revealed that endogenous relaxin is not only a 'pregnancy hormone' but has pleiotropic actions in various tissues in males and non-pregnant females. There is strong interest in relaxin's actions in the vasculature and its utility in the treatment of vascular diseases. Relaxin treatment in rodents for 2-5 days or acute intravenous injection enhances endothelium-dependent relaxation and decreases myogenic tone in resistance arteries. These vascular actions are prolonged, even in the absence of circulating relaxin, and are underpinned by the production of endothelium-derived relaxing factors including nitric oxide, endothelium-derived hyperpolarization and prostacyclin. Relaxin is also capable of remodelling the vascular wall in a variety of blood vessels in disease conditions. Lessons learned in pregnancy research have aided studies investigating the potential therapeutic potential of relaxin in cardiovascular disease. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  15. Plant Vascular Biology 2010

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ding, Biao

    This grant supported the Second International Conference on Plant Vascular Biology (PVB 2010) held July 24-28, 2010 on the campus of Ohio State University, Columbus, Ohio. Biao Ding (Ohio State University; OSU) and David Hannapel (Iowa State University; ISU) served as co-chairs of this conference. Biao Ding served as the local organizer. PVB is defined broadly here to include studies on the biogenesis, structure and function of transport systems in plants, under conditions of normal plant growth and development as well as of plant interactions with pathogens. The transport systems cover broadly the xylem, phloem, plasmodesmata and vascular cell membranes.more » The PVB concept has emerged in recent years to emphasize the integrative nature of the transport systems and approaches to investigate them.« less

  16. Predicting vascular complications in percutaneous coronary interventions.

    PubMed

    Piper, Winthrop D; Malenka, David J; Ryan, Thomas J; Shubrooks, Samuel J; O'Connor, Gerald T; Robb, John F; Farrell, Karen L; Corliss, Mary S; Hearne, Michael J; Kellett, Mirle A; Watkins, Matthew W; Bradley, William A; Hettleman, Bruce D; Silver, Theodore M; McGrath, Paul D; O'Mears, John R; Wennberg, David E

    2003-06-01

    Using a large, current, regional registry of percutaneous coronary interventions (PCI), we identified risk factors for postprocedure vascular complications and developed a scoring system to estimate individual patient risk. A vascular complication (access-site injury requiring treatment or bleeding requiring transfusion) is a potentially avoidable outcome of PCI. Data were collected on 18,137 consecutive patients undergoing PCI in northern New England from January 1997 to December 1999. Multivariate regression was used to identify characteristics associated with vascular complications and to develop a scoring system to predict risk. The rate of vascular complication was 2.98% (541 cases). Variables associated with increased risk in the multivariate analysis included age >or=70, odds ratio (OR) 2.7, female sex (OR 2.4), body surface area <1.6 m(2) (OR 1.9), history of congestive heart failure (OR 1.4), chronic obstructive pulmonary disease (OR 1.5), renal failure (OR 1.9), lower extremity vascular disease (OR 1.4), bleeding disorder (OR 1.68), emergent priority (OR 2.3), myocardial infarction (OR 1.7), shock (1.86), >or=1 type B2 (OR 1.32) or type C (OR 1.7) lesions, 3-vessel PCI (OR 1.5), use of thienopyridines (OR 1.4) or use of glycoprotein IIb/IIIa receptor inhibitors (OR 1.9). The model performed well in tests for significance, discrimination, and calibration. The scoring system captured 75% of actual vascular complications in its highest quintiles of predicted risk. Predicting the risk of post-PCI vascular complications is feasible. This information may be useful for clinical decision-making and institutional efforts at quality improvement.

  17. Additive Manufacturing of Vascular Grafts and Vascularized Tissue Constructs.

    PubMed

    Elomaa, Laura; Yang, Yunzhi Peter

    2017-10-01

    There is a great need for engineered vascular grafts among patients with cardiovascular diseases who are in need of bypass therapy and lack autologous healthy blood vessels. In addition, because of the severe worldwide shortage of organ donors, there is an increasing need for engineered vascularized tissue constructs as an alternative to organ transplants. Additive manufacturing (AM) offers great advantages and flexibility of fabrication of cell-laden, multimaterial, and anatomically shaped vascular grafts and vascularized tissue constructs. Various inkjet-, extrusion-, and photocrosslinking-based AM techniques have been applied to the fabrication of both self-standing vascular grafts and porous, vascularized tissue constructs. This review discusses the state-of-the-art research on the use of AM for vascular applications and the key criteria for biomaterials in the AM of both acellular and cellular constructs. We envision that new smart printing materials that can adapt to their environment and encourage rapid endothelialization and remodeling will be the key factor in the future for the successful AM of personalized and dynamic vascular tissue applications.

  18. Chronic thalidomide administration enhances vascular responsiveness to vasopressin in portal-systemic collaterals of bile duct-ligated rats.

    PubMed

    Chang, Ching-Chih; Wang, Sun-Sang; Huang, Hui-Chun; Lee, Fa-Yauh; Lin, Han-Chieh; Lee, Jing-Yi; Chen, Yi-Chou; Lee, Shou-Dong

    2009-05-01

    Arginine vasopressin (AVP) controls gastroesophageal variceal bleeding, partly due to its vasoconstrictive effect on portal-systemic collaterals. It has been shown that chronic thalidomide treatment decreases portal pressure, attenuates hyperdynamic circulation and inhibits vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF)-alpha in partially portal vein-ligated rats. This study investigated the effects of chronic thalidomide treatment on portal-systemic collateral vascular responsiveness to AVP in common bile duct-ligated (CBDL) cirrhotic rats. In the first series, CBDL-induced cirrhotic rats received thalidomide (50 mg/kg/day orally) or distilled water (control) from the 35th to 42nd day after ligation. On the 43rd day after ligation, the body weight, mean arterial pressure, portal pressure, and heart rate were measured. An in situ collateral vascular perfusion model was used to obtain the cumulative concentration-response curves of collateral vessels to AVP (10(-10) to 3 x 10(-7) M). Plasma levels of VEGF and TNF-alpha were measured, and expressions of VEGF and TNF-alpha mRNA in the left adrenal veins were also determined. In the second series, the cumulative concentration-response curves of collateral vessels to AVP in CBDL rats with or without thalidomide (10(-5) M) preincubation in the perfusate were obtained. The thalidomide and control groups were not significantly different in terms of heart rate, mean arterial pressure and portal pressure (p > 0.05). The collateral vascular perfusion pressure change to AVP was significantly enhanced at 10(-8) M after thalidomide treatment (p = 0.041). Compared with the control group, thalidomide-treated rats had significantly lower plasma VEGF levels (p < 0.001), accompanied by an insignificant reduction in plasma TNF-alpha levels (p > 0.05). The expressions of VEGF and TNF-alpha mRNA in the left adrenal veins of thalidomide-treated CBDL rats were not significantly changed compared with those of the

  19. Towards organ printing: engineering an intra-organ branched vascular tree

    PubMed Central

    Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

    2013-01-01

    Importance of the field Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. Areas covered in this review We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. What the reader will gain The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. Take home message It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a ‘built in’ intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a ‘built in’ intra-organ branched vascular tree. PMID:20132061

  20. Viral haemorrhagic fever and vascular alterations.

    PubMed

    Aleksandrowicz, P; Wolf, K; Falzarano, D; Feldmann, H; Seebach, J; Schnittler, H

    2008-02-01

    Pathogenesis of viral haemorrhagic fever (VHF) is closely associated with alterations of the vascular system. Among the virus families causing VHF, filoviruses (Marburg and Ebola) are the most fatal, and will be focused on here. After entering the body, Ebola primarily targets monocytes/macrophages and dendritic cells. Infected dendritic cells are largely impaired in their activation potency, likely contributing to the immune suppression that occurs during filovirus infection. Monocytes/macrophages, however, immediately activate after viral contact and release reasonable amounts of cytokines that target the vascular system, particularly the endothelial cells. Some underlying molecular mechanisms such as alteration of the vascular endothelial cadherin/catenin complex, tyrosine phosphorylation, expression of cell adhesion molecules, tissue factor and the effect of soluble viral proteins released from infected cells to the blood stream will be discussed.

  1. NADPH Oxidases in Vascular Pathology

    PubMed Central

    Konior, Anna; Schramm, Agata; Czesnikiewicz-Guzik, Marta

    2014-01-01

    Abstract Significance: Reactive oxygen species (ROS) play a critical role in vascular disease. While there are many possible sources of ROS, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases play a central role. They are a source of “kindling radicals,” which affect other enzymes, such as nitric oxide synthase endothelial nitric oxide synthase or xanthine oxidase. This is important, as risk factors for atherosclerosis (hypertension, diabetes, hypercholesterolemia, and smoking) regulate the expression and activity of NADPH oxidases in the vessel wall. Recent Advances: There are seven isoforms in mammals: Nox1, Nox2, Nox3, Nox4, Nox5, Duox1 and Duox2. Nox1, Nox2, Nox4, and Nox5 are expressed in endothelium, vascular smooth muscle cells, fibroblasts, or perivascular adipocytes. Other homologues have not been found or are expressed at very low levels; their roles have not been established. Nox1/Nox2 promote the development of endothelial dysfunction, hypertension, and inflammation. Nox4 may have a role in protecting the vasculature during stress; however, when its activity is increased, it may be detrimental. Calcium-dependent Nox5 has been implicated in oxidative damage in human atherosclerosis. Critical Issues: NADPH oxidase-derived ROS play a role in vascular pathology as well as in the maintenance of normal physiological vascular function. We also discuss recently elucidated mechanisms such as the role of NADPH oxidases in vascular protection, vascular inflammation, pulmonary hypertension, tumor angiogenesis, and central nervous system regulation of vascular function and hypertension. Future Directions: Understanding the role of individual oxidases and interactions between homologues in vascular disease is critical for efficient pharmacological regulation of vascular NADPH oxidases in both the laboratory and clinical practice. Antioxid. Redox Signal. 20, 2794–2814. PMID:24180474

  2. Role of Renin-Angiotensin System and Oxidative Stress on Vascular Inflammation in Insulin Resistence Model

    PubMed Central

    Renna, N. F.; Lembo, C.; Diez, E.; Miatello, R. M.

    2013-01-01

    (1) This study aims to demonstrate the causal involvement of renin angiotensin system (RAS) and oxidative stress (OS) on vascular inflammation in an experimental model of metabolic syndrome (MS) achieved by fructose administration to spontaneously hypertensive rats (FFHR) during 12 weeks. (2) Chronic treatment with candesartan (C) (10 mg/kg per day for the last 6 weeks) or 4OH-Tempol (T) (10−3 mmol/L in drinking water for the last 6 weeks) reversed the increment in metabolic variables and systolic blood pressure. In addition, chronic C treatment reverted cardiovascular remodeling but not T. (3) Furthermore, chronic treatment with C was able to completely reverse the expression of NF-κB and VCAM-1, but T only reduced the expression. C reduced the expression of proatherogenic cytokines as CINC2, CINC3, VEGF, Leptin, TNF-alpha, and MCP-1 and also significantly reduced MIP-3, beta-NGF, and INF-gamma in vascular tissue in this experimental model. T was not able to substantially modify the expression of these cytokines. (4) The data suggest the involvement of RAS in the expression of inflammatory proteins at different vascular levels, allowing the creation of a microenvironment suitable for the creation, perpetuation, growth, and destabilization of vascular injury. PMID:23365721

  3. Role of Renin-Angiotensin system and oxidative stress on vascular inflammation in insulin resistence model.

    PubMed

    Renna, N F; Lembo, C; Diez, E; Miatello, R M

    2013-01-01

    (1) This study aims to demonstrate the causal involvement of renin angiotensin system (RAS) and oxidative stress (OS) on vascular inflammation in an experimental model of metabolic syndrome (MS) achieved by fructose administration to spontaneously hypertensive rats (FFHR) during 12 weeks. (2) Chronic treatment with candesartan (C) (10 mg/kg per day for the last 6 weeks) or 4OH-Tempol (T) (10(-3) mmol/L in drinking water for the last 6 weeks) reversed the increment in metabolic variables and systolic blood pressure. In addition, chronic C treatment reverted cardiovascular remodeling but not T. (3) Furthermore, chronic treatment with C was able to completely reverse the expression of NF-κB and VCAM-1, but T only reduced the expression. C reduced the expression of proatherogenic cytokines as CINC2, CINC3, VEGF, Leptin, TNF-alpha, and MCP-1 and also significantly reduced MIP-3, beta-NGF, and INF-gamma in vascular tissue in this experimental model. T was not able to substantially modify the expression of these cytokines. (4) The data suggest the involvement of RAS in the expression of inflammatory proteins at different vascular levels, allowing the creation of a microenvironment suitable for the creation, perpetuation, growth, and destabilization of vascular injury.

  4. Antidotes for Ricin Intoxication. Effects of Ricin on the Vascular Neuroeffector System

    DTIC Science & Technology

    1992-10-25

    advent of monoclonal antibodies opened up a whole new world of possibilities for the therapeutic use of ricin. By targeting the toxin to a specific...AD-A261 950 CONTRACT NO: DAMD17-90-C-0109 S TITLE: ANTIDOTES FOR RICIN INTOXICATION SUBTITLE: Effects of Ricin on the Vascular Neuroeffector System...PRINCIPAL INVESTIGATOR: Casey Robinson AUTIORS: Victoria J. Christiansen, Chia-Hsuh Hsu, Lin Zhang CONTRACTING ORGANIZATION: University of Oklahoma

  5. Determination of Vascular Waterfall Phenomenon by Bedside Measurement of Mean Systemic Filling Pressure and Critical Closing Pressure in the Intensive Care Unit

    PubMed Central

    Maas, Jacinta J.; de Wilde, Rob B.; Aarts, Leon P.; Pinsky, Michael R.; Jansen, Jos R.

    2012-01-01

    Background Mean systemic filling pressure (Pmsf) can be determined at the bedside by measuring central venous pressure (Pcv) and cardiac output (CO) during inspiratory hold maneuvers. Critical closing pressure (Pcc) can be determined using the same method measuring arterial pressure (Pa) and CO. If Pcc > Pmsf there is then a vascular waterfall. In this study we assessed the existence of a waterfall and its implications for the calculation of vascular resistances by determining Pmsf and Pcc at the bedside. Methods In 10 mechanically ventilated postcardiac surgery patients inspiratory hold maneuvers were performed, transiently increasing Pcv and decreasing Pa and CO to four different steady-state levels. For each patient values of Pcv and CO were plotted in a venous return curve to determine Pmsf. Similarly, Pcc was determined with a ventricular output curve plotted for Pa and CO. Measurements were performed in each patient before and after volume expansion with 0.5 l colloid and vascular resistances were calculated. Results For every patient the relationship between the four measurements of Pcv and CO and of Pa and CO was linear. Baseline Pmsf was 18.7±4.0 (mean±SD) mmHg and differed significantly from Pcc 45.5±11.1 mmHg; (p<0.0001). The difference of Pcc and Pmsf was 26.8±10.7 mmHg, indicating the presence of a systemic vascular waterfall. Volume expansion increased Pmsf (26.3±3.2 mmHg), Pcc (51.5±9.0 mmHg) and CO (5.5±1.8 to 6.8±1.8 l·min−1). Arterial (upstream of Pcc) and venous (down-stream of Pmsf) vascular resistance were 8.27±4.45 and 2.75±1.23 mmHg·min·l−1; the sum of both (11.01 mmHg·min·l−1) was significantly different from total systemic vascular resistance (16.56±8.57 mmHg·min·l−1, p=0.005). Arterial resistance was related to total resistance. Conclusions Vascular pressure gradients in cardiac surgery patients suggest the presence of a vascular waterfall phenomenon, which is not affected by CO. Thus measures of total systemic

  6. Collaborative Modelling of the Vascular System--Designing and Evaluating a New Learning Method for Secondary Students

    ERIC Educational Resources Information Center

    Haugwitz, Marion; Sandmann, Angela

    2010-01-01

    Understanding biological structures and functions is often difficult because of their complexity and micro-structure. For example, the vascular system is a complex and only partly visible system. Constructing models to better understand biological functions is seen as a suitable learning method. Models function as simplified versions of real…

  7. A comparison of the boomerang wire vascular access management system versus manual compression alone during percutaneous diagnostic and interventional cardiovascular procedures.

    PubMed

    Echeverria, Angela; Krajcer, Zvonimir

    2016-01-01

    Vascular closure devices allow for early sheath removal, allowing for earlier patient mobilization The Boomerang vascular access management system does not alter arterial integrity for future interventions Access site complications provide significant morbidity in diagnostic and therapeutic interventions. © 2016 Wiley Periodicals, Inc.

  8. A low cost Doppler system for vascular dialysis access surveillance.

    PubMed

    Molina, P S C; Moraes, R; Baggio, J F R; Tognon, E A

    2004-01-01

    The National Kidney Foundation guidelines for vascular access recommend access surveillance to avoid morbidity among patients undergoing hemodialysis. Methods to detect access failure based on CW Doppler system are being proposed to implement surveillance programs at lower cost. This work describes a low cost Doppler system implemented in a PC notebook designed to carry out this task. A Doppler board samples the blood flow velocity and delivers demodulated quadrature Doppler signals. These signals are sampled by a notebook sound card. Software for Windows OS (running at the notebook) applies CFFT to consecutive 11.6 ms intervals of Doppler signals. The sonogram is presented on the screen in real time. The software also calculates the maximum and the intensity weighted mean frequency envelopes. Since similar systems employ DSP boards to process the Doppler signals, cost reduction was achieved. The Doppler board electronic circuits and routines to process the Doppler signals are presented.

  9. Cytoglobin regulates blood pressure and vascular tone through nitric oxide metabolism in the vascular wall

    PubMed Central

    Liu, Xiaoping; El-Mahdy, Mohamed A.; Boslett, James; Varadharaj, Saradhadevi; Hemann, Craig; Abdelghany, Tamer M.; Ismail, Raed S.; Little, Sean C.; Zhou, Danlei; Thuy, Le Thi Thanh; Kawada, Norifumi; Zweier, Jay L.

    2017-01-01

    The identity of the specific nitric oxide dioxygenase (NOD) that serves as the main in vivo regulator of O2-dependent NO degradation in smooth muscle remains elusive. Cytoglobin (Cygb) is a recently discovered globin expressed in fibroblasts and smooth muscle cells with unknown function. Cygb, coupled with a cellular reducing system, efficiently regulates the rate of NO consumption by metabolizing NO in an O2-dependent manner with decreased NO consumption in physiological hypoxia. Here we show that Cygb is a major regulator of NO degradation and cardiovascular tone. Knockout of Cygb greatly prolongs NO decay, increases vascular relaxation, and lowers blood pressure and systemic vascular resistance. We further demonstrate that downregulation of Cygb prevents angiotensin-mediated hypertension. Thus, Cygb has a critical role in the regulation of vascular tone and disease. We suggest that modulation of the expression and NOD activity of Cygb represents a strategy for the treatment of cardiovascular disease. PMID:28393874

  10. Cytoglobin regulates blood pressure and vascular tone through nitric oxide metabolism in the vascular wall

    NASA Astrophysics Data System (ADS)

    Liu, Xiaoping; El-Mahdy, Mohamed A.; Boslett, James; Varadharaj, Saradhadevi; Hemann, Craig; Abdelghany, Tamer M.; Ismail, Raed S.; Little, Sean C.; Zhou, Danlei; Thuy, Le Thi Thanh; Kawada, Norifumi; Zweier, Jay L.

    2017-04-01

    The identity of the specific nitric oxide dioxygenase (NOD) that serves as the main in vivo regulator of O2-dependent NO degradation in smooth muscle remains elusive. Cytoglobin (Cygb) is a recently discovered globin expressed in fibroblasts and smooth muscle cells with unknown function. Cygb, coupled with a cellular reducing system, efficiently regulates the rate of NO consumption by metabolizing NO in an O2-dependent manner with decreased NO consumption in physiological hypoxia. Here we show that Cygb is a major regulator of NO degradation and cardiovascular tone. Knockout of Cygb greatly prolongs NO decay, increases vascular relaxation, and lowers blood pressure and systemic vascular resistance. We further demonstrate that downregulation of Cygb prevents angiotensin-mediated hypertension. Thus, Cygb has a critical role in the regulation of vascular tone and disease. We suggest that modulation of the expression and NOD activity of Cygb represents a strategy for the treatment of cardiovascular disease.

  11. Convergent evolution of vascular optimization in kelp (Laminariales).

    PubMed

    Drobnitch, Sarah Tepler; Jensen, Kaare H; Prentice, Paige; Pittermann, Jarmila

    2015-10-07

    Terrestrial plants and mammals, although separated by a great evolutionary distance, have each arrived at a highly conserved body plan in which universal allometric scaling relationships govern the anatomy of vascular networks and key functional metabolic traits. The universality of allometric scaling suggests that these phyla have each evolved an 'optimal' transport strategy that has been overwhelmingly adopted by extant species. To truly evaluate the dominance and universality of vascular optimization, however, it is critical to examine other, lesser-known, vascularized phyla. The brown algae (Phaeophyceae) are one such group--as distantly related to plants as mammals, they have convergently evolved a plant-like body plan and a specialized phloem-like transport network. To evaluate possible scaling and optimization in the kelp vascular system, we developed a model of optimized transport anatomy and tested it with measurements of the giant kelp, Macrocystis pyrifera, which is among the largest and most successful of macroalgae. We also evaluated three classical allometric relationships pertaining to plant vascular tissues with a diverse sampling of kelp species. Macrocystis pyrifera displays strong scaling relationships between all tested vascular parameters and agrees with our model; other species within the Laminariales display weak or inconsistent vascular allometries. The lack of universal scaling in the kelps and the presence of optimized transport anatomy in M. pyrifera raises important questions about the evolution of optimization and the possible competitive advantage conferred by optimized vascular systems to multicellular phyla. © 2015 The Author(s).

  12. Vascular tumors of the choroid and retina

    PubMed Central

    Shanmugam, P Mahesh; Ramanjulu, Rajesh

    2015-01-01

    Vascular tumors of the retina and choroid can be seen occasionally. In the following article, the key clinical and diagnostic features of the major retinal and choroidal vascular tumors, their systemic associations, and the literature pertaining to the most currently available treatment strategies are reviewed. PMID:25827544

  13. Endoscopic Management of Vascular Sinonasal Tumors, Including Angiofibroma.

    PubMed

    Snyderman, Carl H; Pant, Harshita

    2016-06-01

    The greatest challenge in the surgical treatment of angiofibromas is dealing with the hypervascularity of these tumors. Staging systems that take into account the vascularity of the tumor may be more prognostic. A variety of treatment strategies are used to deal with the vascularity of angiofibromas, including preoperative embolization, segmentation of the tumor into vascular territories, use of hemostatic tools, and staging of surgery. Even large angiofibromas with intracranial extension and residual vascularity can be successfully managed by a skull base team using endoscopic techniques. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Spectral imaging based in vivo model system for characterization of tumor microvessel response to vascular targeting agents

    NASA Astrophysics Data System (ADS)

    Wankhede, Mamta

    Functional vasculature is vital for tumor growth, proliferation, and metastasis. Many tumor-specific vascular targeting agents (VTAs) aim to destroy this essential tumor vasculature to induce indirect tumor cell death via oxygen and nutrition deprivation. The tumor angiogenesis-inhibiting anti-angiogenics (AIs) and the established tumor vessel targeting vascular disrupting agents (VDAs) are the two major players in the vascular targeting field. Combination of VTAs with conventional therapies or with each other, have been shown to have additive or supra-additive effects on tumor control and treatment. Pathophysiological changes post-VTA treatment in terms of structural and vessel function changes are important parameters to characterize the treatment efficacy. Despite the abundance of information regarding these parameters acquired using various techniques, there remains a need for a quantitative, real-time, and direct observation of these phenomenon in live animals. Through this research we aspired to develop a spectral imaging based mouse tumor system for real-time in vivo microvessel structure and functional measurements for VTA characterization. A model tumor system for window chamber studies was identified, and then combinatorial effects of VDA and AI were characterized in model tumor system. (Full text of this dissertation may be available via the University of Florida Libraries web site. Please check http://www.uflib.ufl.edu/etd.html)

  15. [Vascular Lesions of Vocal Folds - Part 2: Perpendicular Vascular Lesions].

    PubMed

    Arens, C; Glanz, H; Voigt-Zimmermann, S

    2015-11-01

    The present work aims at a systematic pathogenetic description of perpendicular vascular changes in the vocal folds. Unlike longitudinal vascular changes, like ectasia and meander, perpendicular vascular changes can be observed in bening lesions. They predominantly occur as typical vascular loops in exophytic lesions, especially in recurrent respiratory papillomatosis (RRP), pre-cancerous and cancerous diseases of the larynx and vocal folds. Neoangiogenesis is caused by an epithelial growth stimulus in the early phase of cancerous genesis. In RRP the VVC impress by a single, long vessel loop with a narrow angle turning point in the each single papilla of the papilloma. In pre- and cancerous lesions the vascular loop is located directly underneath the epithelium. During progressive tumor growth, vascular loops develop an increasingly irregular, convoluted, spirally shape. The arrangement of the vascular loops is primarily still symmetrical. In the preliminary stage of tumor development occurs by neoangiogenesis to a microvascular compression. In advanced vocal fold carcinoma the regular vascular vocal fold structure is destroyed. The various stages of tumor growth are also characterized by typical primary epithelial and secondary connective tissue changes. The characteristic triad of vascular, epithelial and connective tissue changes therefore plays an important role in differential diagnosis. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Neural guidance molecules regulate vascular remodeling and vessel navigation.

    PubMed

    Eichmann, Anne; Makinen, Taija; Alitalo, Kari

    2005-05-01

    The development of the embryonic blood vascular and lymphatic systems requires the coordinated action of several transcription factors and growth factors that target endothelial and periendothelial cells. However, according to recent studies, the precise "wiring" of the vascular system does not occur without an ordered series of guidance decisions involving several molecules initially discovered for axons in the nervous system, including ephrins, netrins, slits, and semaphorins. Here, we summarize the new advances in our understanding of the roles of these axonal pathfinding molecules in vascular remodeling and vessel guidance, indicating that neuronal axons and vessel sprouts use common molecular mechanisms for navigation in the body.

  17. Sarcoma spreads primarily through the vascular system: are there biomarkers associated with vascular spread?

    PubMed

    Pennacchioli, Elisabetta; Tosti, Giulio; Barberis, Massimo; De Pas, Tommaso M; Verrecchia, Francesco; Menicanti, Claudia; Testori, Alessandro; Mazzarol, Giovanni

    2012-10-01

    Sarcomas are a heterogeneous group of tumors with specific molecular characteristics and currently classified on the basis of their tissue of origin and histologic appearance. Except for epithelioid sarcoma, clear cell sarcoma, angiosarcoma and rhabdomyosarcoma, which may spread to regional lymph nodes, the other histotypes spread via the vascular system to the lungs most of the time. A variety of molecular approaches, including gene expression profiling, have identified candidate biomarkers and generated insights into sarcoma biology. The comprehension of the pathogenesis of this malignancy according to the mesenchymal stem cell hypothesis parallels the description of several molecular pathways deregulated in sarcoma. Individuation of vascular spread biomarkers is actually focused on the study of factors involved both in hemostasis and angiogenesis. Interestingly the microenvironment of sarcomas showed the very same mesenchymal origin of the surrounding stromal cells. The presence of circulating tumor cells and miRNAs in blood samples of sarcoma patients represents the possibility not only to better stratify patients group according to the prognosis but also to tailor new individualized therapy. So, it could be predicted that some genes expressed in a specific sarcoma might have prognostic significance or therapeutic targeting potential and molecular targets can be identified in the tumor or in the tumor microenvironment. Therefore the initial evaluation of a sarcoma patient should include in-depth genetic evaluation including karyotyping and c-DNA/protein expression profiling. The chemokine signaling demonstrated to be deeply implicated in sarcoma development as well as to have a significant role in development of metastatic disease, especially in directing tumor cells towards the preferential sites of metastases in sarcoma, lung and bone. It is unsolved if the blood stream is a more favorable environment compared to lymphatic or if lymph nodes are more efficient

  18. Improved vascularization of planar membrane diffusion devices following continuous infusion of vascular endothelial growth factor.

    PubMed

    Trivedi, N; Steil, G M; Colton, C K; Bonner-Weir, S; Weir, G C

    2000-01-01

    Improving blood vessel formation around an immunobarrier device should improve the survival of the encapsulated tissue. In the present study we investigated the formation of new blood vessels around a planar membrane diffusion device (the Baxter Theracyte System) undergoing a continuous infusion of vascular endothelial growth factor through the membranes and into the surrounding tissue. Each device (20 microl) had both an inner immunoisolation membrane and an outer vascularizing membrane. Human recombinant vascular endothelial growth factor-165 was infused at 100 ng/day (low dose: n = 6) and 500 ng/day (high dose: n = 7) for 10 days into devices implanted s.c. in Sprague-Dawley rats; noninfused devices transplanted for an identical period were used as controls (n = 5). Two days following the termination of VEGF infusion, devices were loaded with 20 microl of Lispro insulin (1 U/kg) and the kinetics of insulin release from the lumen of the device was assessed. Devices were then explanted and the number of blood vessels (capillary and noncapillary) was quantified using morphometry. High-dose vascular endothelial growth factor infusion resulted in two- to threefold more blood vessels around the device than that obtained with the noninfused devices and devices infused with low-dose vascular endothelial growth factor. This increase in the number of blood vessels was accompanied by a modest increase in insulin diffusion from the device in the high-dose vascular endothelial growth factor infusion group. We conclude that vascular endothelial growth factor can be used to improve blood vessel formation adjacent to planar membrane diffusion devices.

  19. Retinal vascular changes are a marker for cerebral vascular diseases

    PubMed Central

    Moss, Heather E.

    2016-01-01

    The retinal circulation is a potential marker of cerebral vascular disease because it shares origin and drainage with the intracranial circulation and because it can be directly visualized using ophthalmoscopy. Cross sectional and cohort studies have demonstrated associations between chronic retinal and cerebral vascular disease, acute retinal and cerebral vascular disease and chronic retinal vascular disease and acute cerebral vascular disease. In particular, certain qualitative features of retinopathy, retinal artery occlusion and increased retinal vein caliber are associated with concurrent and future cerebrovascular events. These associations persist after accounting for confounding variables known to be disease-causing in both circulations, which supports the potential use of retinal vasculature findings to stratify individuals with regards to cerebral vascular disease risk. PMID:26008809

  20. Notch Signaling in Vascular Smooth Muscle Cells

    PubMed Central

    Baeten, J.T.; Lilly, B.

    2018-01-01

    The Notch signaling pathway is a highly conserved pathway involved in cell fate determination in embryonic development and also functions in the regulation of physiological processes in several systems. It plays an especially important role in vascular development and physiology by influencing angiogenesis, vessel patterning, arterial/venous specification, and vascular smooth muscle biology. Aberrant or dysregulated Notch signaling is the cause of or a contributing factor to many vascular disorders, including inherited vascular diseases, such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, associated with degeneration of the smooth muscle layer in cerebral arteries. Like most signaling pathways, the Notch signaling axis is influenced by complex interactions with mediators of other signaling pathways. This complexity is also compounded by different members of the Notch family having both overlapping and unique functions. Thus, it is vital to fully understand the roles and interactions of each Notch family member in order to effectively and specifically target their exact contributions to vascular disease. In this chapter, we will review the Notch signaling pathway in vascular smooth muscle cells as it relates to vascular development and human disease. PMID:28212801

  1. [Study on protective effect of Tianji soft capsule on blood lipids, internal antioxidant system and vascular endothelial system in hyperlipidemia rats].

    PubMed

    Ma, Hai-ying; Chen, Jin-yao; Zhang, Li-shi

    2011-11-01

    To study the protective effects of Tianji soft capsule (TJSC) on blood lipids, internal antioxidant system and vascular endothelial system in hyperlipidemia rats. Seventy two healthy male rats were divided into six groups. The rats in control group were administered with ordinary diet. The rats in model group were fed with high cholesterol/lipid diet to induce hyperlipidemia. The rats in TJSC and CoQ10 groups were fed with high cholesterol/lipid diet, and treated with TJSC at different doses of 83 (low-dose group, L), 250 (middle-dose group, M), 750 (high-dose group, H) mg/kg, and CoQ10 at the dose of 83 mg/kg, respectively. All animals were put to death after four weeks, effects on lipid level; antioxidant system and endothelial system were evaluated through detection of total cholesterol (TC), triglyceride (TG), very low density lipoprotein (VLDL), atherogenic index (AI), malondidehyde (MDA) and plasma endothelin (ET), HDL/TC ratio, activities of superoxide dismutase (SOD) and nitric oxide (NO). Compared with model group, serum TC, TG, VLDL, AI, MDA and ET reduced and the HDL/TC ratio increased, meanwhile activities of SOD and NO were enhanced. TJSC can regulate the lipid metabolism, enhance antioxidant system and protect the vascular endothelia system in hyperlipiemic rats.

  2. An Automated Mouse Tail Vascular Access System by Vision and Pressure Feedback.

    PubMed

    Chang, Yen-Chi; Berry-Pusey, Brittany; Yasin, Rashid; Vu, Nam; Maraglia, Brandon; Chatziioannou, Arion X; Tsao, Tsu-Chin

    2015-08-01

    This paper develops an automated vascular access system (A-VAS) with novel vision-based vein and needle detection methods and real-time pressure feedback for murine drug delivery. Mouse tail vein injection is a routine but critical step for preclinical imaging applications. Due to the small vein diameter and external disturbances such as tail hair, pigmentation, and scales, identifying vein location is difficult and manual injections usually result in poor repeatability. To improve the injection accuracy, consistency, safety, and processing time, A-VAS was developed to overcome difficulties in vein detection noise rejection, robustness in needle tracking, and visual servoing integration with the mechatronics system.

  3. Treating vascular lesions.

    PubMed

    Astner, Susanne; Anderson, R Rox

    2005-01-01

    The treatment of acquired vascular lesions is one of the most commonly requested and performed cutaneous laser procedures. Furthermore, every year, 40,000 children are born in the United States each with congenital vascular lesions and malformations. Laser treatment of vascular lesion is based on the principle of selective photothermolysis, conceived in the 1980s. A variety of different lasers and light sources have since been used in the treatment of vascular lesions: lasers with wavelengths between green and yellow, near infrared lasers, and broadband light sources. Despite limitations, this remains the treatment of choice today. This publication addresses acquired and congenital vascular lesions as different entities and proposes a separation of vascular lesions into those that can easily be treated from those where clearance is difficult. Different treatment modalities and the various endpoints of individual vascular lesions will be discussed.

  4. [Vascular lesions of vocal folds--part 1: horizontal vascular lesions].

    PubMed

    Voigt-Zimmermann, S; Arens, C

    2014-12-01

    In recent decades, the endoscopic methods and technologies for laryngeal examination have improved so much that not only epithelial changes, but also vascular changes are recognizable at earlier stages. When comparing newer and older literature, the associated increasingly differentiated descriptions of such visible vascular changes of the vocal folds lead to terminological blurring and shifts of meaning. This complicates the technical-scientific discourse. The aim of the present work is a theoretical and conceptual clarification of early vascular changes of vocal folds. Horizontal changes of benigne vascular diseases, e. g. vessel ectasia, meander, increasing number and branching of vessels, change of direction may develop in to manifest vascular lesions, like varicosis, polyps and in case of ruptures to haemorrhages of vocal folds. These beginning and reversible vascular changes, when early detected and discussed basing on etiological knowledge, may lead to more differentiated prognostic statements and adequate therapeutic decisions, e. g. phonosurgery, functional voice therapy, voice hygiene and voice rest. Vertical vascular changes, like vessel loops, occur primarily in laryngeal papilloma, pre-cancerous and cancerous changes of the vocal folds. Already in small cancerous lesions of the vocal folds the vascular architecture is completely destroyed. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Angiogenic T cell expansion correlates with severity of peripheral vascular damage in systemic sclerosis.

    PubMed

    Manetti, Mirko; Pratesi, Sara; Romano, Eloisa; Bellando-Randone, Silvia; Rosa, Irene; Guiducci, Serena; Fioretto, Bianca Saveria; Ibba-Manneschi, Lidia; Maggi, Enrico; Matucci-Cerinic, Marco

    2017-01-01

    The mechanisms underlying endothelial cell injury and defective vascular repair in systemic sclerosis (SSc) remain unclear. Since the recently discovered angiogenic T cells (Tang) may have an important role in the repair of damaged endothelium, this study aimed to analyze the Tang population in relation to disease-related peripheral vascular features in SSc patients. Tang (CD3+CD31+CXCR4+) were quantified by flow cytometry in peripheral blood samples from 39 SSc patients and 18 healthy controls (HC). Circulating levels of the CXCR4 ligand stromal cell-derived factor (SDF)-1α and proangiogenic factors were assessed in paired serum samples by immunoassay. Serial skin sections from SSc patients and HC were subjected to CD3/CD31 and CD3/CXCR4 double immunofluorescence. Circulating Tang were significantly increased in SSc patients with digital ulcers (DU) compared either with SSc patients without DU or with HC. Tang levels were significantly higher in SSc patients with late nailfold videocapillaroscopy (NVC) pattern than in those with early/active NVC patterns and in HC. No difference in circulating Tang was found when comparing either SSc patients without DU or patients with early/active NVC patterns and HC. In SSc peripheral blood, Tang percentage was inversely correlated to levels of SDF-1α and CD34+CD133+VEGFR-2+ endothelial progenitor cells (EPC), and positively correlated to levels of vascular endothelial growth factor and matrix metalloproteinase-9. Tang were frequently detected in SSc dermal perivascular inflammatory infiltrates. In summary, our findings demonstrate for the first time that Tang cells are selectively expanded in the circulation of SSc patients displaying severe peripheral vascular complications like DU. In SSc, Tang may represent a potentially useful biomarker reflecting peripheral vascular damage severity. Tang expansion may be an ineffective attempt to compensate the need for increased angiogenesis and EPC function. Further studies are

  6. Vascular dysfunctions following spinal cord injury

    PubMed Central

    Popa, F; Grigorean, VT; Onose, G; Sandu, AM; Popescu, M; Burnei, G; Strambu, V; Sinescu, C

    2010-01-01

    The aim of this article is to analyze the vascular dysfunctions occurring after spinal cord injury (SCI). Vascular dysfunctions are common complications of SCI. Cardiovascular disturbances are the leading causes of morbidity and mortality in both acute and chronic stages of SCI. Neuroanatomy and physiology of autonomic nervous system, sympathetic and parasympathetic, is reviewed. SCI implies disruption of descendent pathways from central centers to spinal sympathetic neurons, originating in intermediolateral nuclei of T1–L2 cord segments. Loss of supraspinal control over sympathetic nervous system results in reduced overall sympathetic activity below the level of injury and unopposed parasympathetic outflow through intact vagal nerve. SCI associates significant vascular dysfunction. Spinal shock occurs during the acute phase following SCI and it is a transitory suspension of function and reflexes below the level of the injury. Neurogenic shock, part of spinal shock, consists of severe arterial hypotension and bradycardia. Autonomic dysreflexia appears during the chronic phase, after spinal shock resolution, and it is a life–threatening syndrome of massive imbalanced reflex sympathetic discharge occurring in patients with SCI above the splanchnic sympathetic outflow (T5–T6). Arterial hypotension with orthostatic hypotension occurs in both acute and chronic phases. The etiology is multifactorial. We described a few factors influencing the orthostatic hypotension occurrence in SCI: sympathetic nervous system dysfunction, low plasma catecholamine levels, rennin–angiotensin–aldosterone activity, peripheral alpha–adrenoceptor hyperresponsiveness, impaired function of baroreceptors, hyponatremia and low plasmatic volume, cardiovascular deconditioning, morphologic changes in sympathetic neurons, plasticity within spinal circuits, and motor deficit leading to loss of skeletal muscle pumping activity. Additional associated cardiovascular concerns in SCI, such as

  7. Cardiac output and systemic vascular resistance: Clinical assessment compared with a noninvasive objective measurement in children with shock.

    PubMed

    Razavi, Asma; Newth, Christopher J L; Khemani, Robinder G; Beltramo, Fernando; Ross, Patrick A

    2017-06-01

    To evaluate physician assessment of cardiac output and systemic vascular resistance in patients with shock compared with an ultrasonic cardiac output monitor (USCOM). To explore potential changes in therapy decisions if USCOM data were available using physician intervention answers. Double-blinded, prospective, observational study in a tertiary hospital pediatric intensive care unit. Forty children (<18years) admitted with shock, requiring ongoing volume resuscitation or inotropic support. Two to 3 physicians clinically assessed cardiac output and systemic vascular resistance, categorizing them as high, normal, or low. An investigator simultaneously measured cardiac index (CI) and systemic vascular resistance index (SVRI) with USCOM categorized as high, normal, or low. Overall agreement between physician and USCOM for CI (48.5% [κ = 0.18]) and SVRI (45.9% [κ = 0.16]) was poor. Interobserver agreement was also poor for CI (58.7% [κ = 0.33]) and SVRI (52.3% [κ = 0.28]). Comparing theoretical physician interventions to "acceptable" or "unacceptable" clinical interventions, based on USCOM measurement, 56 (21%) physician interventions were found to be "unacceptable." There is poor agreement between physician-assessed CI and SVRI and USCOM, with significant interobserver variability among physicians. Objective measurement of CI and SVRI may reduce variability and improve diagnostic accuracy. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Air Pollution-Induced Vascular Dysfunction: Potential Role of Endothelin-1 (ET-1) System

    PubMed Central

    Finch, Jordan; Conklin, Daniel J.

    2015-01-01

    Exposure to air pollution negatively impacts cardiovascular health. Studies show that increased exposure to a number of airborne pollutants increases the risk for cardiovascular disease progression, myocardial events, and cardiovascular mortality. A hypothesized mechanism linking air pollution and cardiovascular disease is the development of systemic inflammation and endothelium dysfunction, the latter of which can result from an imbalance of vasoactive factors within the vasculature. Endothelin-1 (ET-1) is a potent peptide vasoconstrictor that plays a significant role in regulating vascular homeostasis. It has been reported that the production and function of ET-1 and its receptors are upregulated in a number of disease states associated with endothelium dysfunction including hypertension and atherosclerosis. This mini-review surveys epidemiological and experimental air pollution studies focused on ET-1 dysregulation as a plausible mechanism underlying the development of cardiovascular disease. Although alterations in ET-1 system components are observed in some studies, there remains a need for future research to clarify whether these specific changes are compensatory or causally related to vascular injury and dysfunction. Moreover, further research may test the efficacy of selective ET-1 pharmacological interventions (e.g., ETA receptor inhibitors) to determine whether these treatments could impede the deleterious impact of air pollution exposure on cardiovascular health. PMID:26148452

  9. Air Pollution-Induced Vascular Dysfunction: Potential Role of Endothelin-1 (ET-1) System.

    PubMed

    Finch, Jordan; Conklin, Daniel J

    2016-07-01

    Exposure to air pollution negatively impacts cardiovascular health. Studies show that increased exposure to a number of airborne pollutants increases the risk for cardiovascular disease progression, myocardial events, and cardiovascular mortality. A hypothesized mechanism linking air pollution and cardiovascular disease is the development of systemic inflammation and endothelium dysfunction, the latter of which can result from an imbalance of vasoactive factors within the vasculature. Endothelin-1 (ET-1) is a potent peptide vasoconstrictor that plays a significant role in regulating vascular homeostasis. It has been reported that the production and function of ET-1 and its receptors are upregulated in a number of disease states associated with endothelium dysfunction including hypertension and atherosclerosis. This mini-review surveys epidemiological and experimental air pollution studies focused on ET-1 dysregulation as a plausible mechanism underlying the development of cardiovascular disease. Although alterations in ET-1 system components are observed in some studies, there remains a need for future research to clarify whether these specific changes are compensatory or causally related to vascular injury and dysfunction. Moreover, further research may test the efficacy of selective ET-1 pharmacological interventions (e.g., ETA receptor inhibitors) to determine whether these treatments could impede the deleterious impact of air pollution exposure on cardiovascular health.

  10. Vascular Cognitive Impairment.

    PubMed

    Dichgans, Martin; Leys, Didier

    2017-02-03

    Cerebrovascular disease typically manifests with stroke, cognitive impairment, or both. Vascular cognitive impairment refers to all forms of cognitive disorder associated with cerebrovascular disease, regardless of the specific mechanisms involved. It encompasses the full range of cognitive deficits from mild cognitive impairment to dementia. In principle, any of the multiple causes of clinical stroke can cause vascular cognitive impairment. Recent work further highlights a role of microinfarcts, microhemorrhages, strategic white matter tracts, loss of microstructural tissue integrity, and secondary neurodegeneration. Vascular brain injury results in loss of structural and functional connectivity and, hence, compromise of functional networks within the brain. Vascular cognitive impairment is common both after stroke and in stroke-free individuals presenting to dementia clinics, and vascular pathology frequently coexists with neurodegenerative pathology, resulting in mixed forms of mild cognitive impairment or dementia. Vascular dementia is now recognized as the second most common form of dementia after Alzheimer's disease, and there is increasing awareness that targeting vascular risk may help to prevent dementia, even of the Alzheimer type. Recent advances in neuroimaging, neuropathology, epidemiology, and genetics have led to a deeper understanding of how vascular disease affects cognition. These new findings provide an opportunity for the present reappraisal of vascular cognitive impairment. We further briefly address current therapeutic concepts. © 2017 American Heart Association, Inc.

  11. Branding of vascular surgery.

    PubMed

    Perler, Bruce A

    2008-03-01

    The Society for Vascular Surgery surveyed primary care physicians (PCPs) to understand how PCPs make referral decisions for their patients with peripheral vascular disease. Responses were received from 250 PCPs in 44 states. More than 80% of the respondents characterized their experiences with vascular surgeons as positive or very positive. PCPs perceive that vascular surgeons perform "invasive" procedures and refer patients with the most severe vascular disease to vascular surgeons but were more than twice as likely to refer patients to cardiologists, believing they are better able to perform minimally invasive procedures. Nevertheless, PCPs are receptive to the notion of increasing referrals to vascular surgeons. A successful branding campaign will require considerable education of referring physicians about the totality of traditional vascular and endovascular care increasingly provided by the contemporary vascular surgical practice and will be most effective at the local grassroots level.

  12. Obesity and risk of vascular disease: importance of endothelium-dependent vasoconstriction

    PubMed Central

    Barton, Matthias; Baretella, Oliver; Meyer, Matthias R

    2012-01-01

    Obesity has become a serious global health issue affecting both adults and children. Recent devolopments in world demographics and declining health status of the world's population indicate that the prevalence of obesity will continue to increase in the next decades. As a disease, obesity has deleterious effects on metabolic homeostasis, and affects numerous organ systems including heart, kidney and the vascular system. Thus, obesity is now regarded as an independent risk factor for atherosclerosis-related diseases such as coronary artery disease, myocardial infarction and stroke. In the arterial system, endothelial cells are both the source and target of factors contributing to atherosclerosis. Endothelial vasoactive factors regulate vascular homeostasis under physiological conditions and maintain basal vascular tone. Obesity results in an imbalance between endothelium-derived vasoactive factors favouring vasoconstriction, cell growth and inflammatory activation. Abnormal regulation of these factors due to endothelial cell dysfunction is both a consequence and a cause of vascular disease processes. Finally, because of the similarities of the vascular pathomechanisms activated, obesity can be considered to cause accelerated, ‘premature’ vascular aging. Here, we will review some of the pathomechanisms involved in obesity-related activation of endothelium-dependent vasoconstriction, the clinical relevance of obesity-associated vascular risk, and therapeutic interventions using ‘endothelial therapy’ aiming at maintaining or restoring vascular endothelial health. LINKED ARTICLES This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3 PMID:21557734

  13. Obesity and risk of vascular disease: importance of endothelium-dependent vasoconstriction.

    PubMed

    Barton, Matthias; Baretella, Oliver; Meyer, Matthias R

    2012-02-01

    Obesity has become a serious global health issue affecting both adults and children. Recent devolopments in world demographics and declining health status of the world's population indicate that the prevalence of obesity will continue to increase in the next decades. As a disease, obesity has deleterious effects on metabolic homeostasis, and affects numerous organ systems including heart, kidney and the vascular system. Thus, obesity is now regarded as an independent risk factor for atherosclerosis-related diseases such as coronary artery disease, myocardial infarction and stroke. In the arterial system, endothelial cells are both the source and target of factors contributing to atherosclerosis. Endothelial vasoactive factors regulate vascular homeostasis under physiological conditions and maintain basal vascular tone. Obesity results in an imbalance between endothelium-derived vasoactive factors favouring vasoconstriction, cell growth and inflammatory activation. Abnormal regulation of these factors due to endothelial cell dysfunction is both a consequence and a cause of vascular disease processes. Finally, because of the similarities of the vascular pathomechanisms activated, obesity can be considered to cause accelerated, 'premature' vascular aging. Here, we will review some of the pathomechanisms involved in obesity-related activation of endothelium-dependent vasoconstriction, the clinical relevance of obesity-associated vascular risk, and therapeutic interventions using 'endothelial therapy' aiming at maintaining or restoring vascular endothelial health. This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

  14. Cell-Responsive Hydrogel for Encapsulation of Vascular Cells

    PubMed Central

    Kraehenbuehl, Thomas P.; Ferreira, Lino S.; Zammaretti, Prisca; Hubbell, Jeffrey A.; Langer, Robert

    2014-01-01

    The in vitro potential of a synthetic matrix metalloproteinase (MMP)-responsive polyethylene glycol) (PEG)-based hydrogel as a bioactive co-encapsulation system for vascular cells and a small bioactive peptide, thymosin β4 (Tp4), was examined. We show that the physical incorporation of Tβ4 in this bioactive matrix creates a three-dimensional (3D) environment conducive for human umbilical vein endothelial cell (HUVEC) adhesion, survival, migration and organization. Gels with entrapped Tβ4 increased the survival of HUVEC compared to gels without Tp4, and significantly up-regulated the endothelial genes vascular endothelial-cadherin and angiopoietin-2, whereas von Willebrand factor was significantly down-regulated. Incorporation of Tβ4 significantly increased MMP-2 and MMP-9 secretion of encapsulated HUVEC. The gel acts as a controlled Tβ4-release system, as MMP-2 and MMP-9 enzymes trigger the release. In addition, Tβ4 facilitated HUVEC attachment and induced vascular-like network formation upon the PEG-hydrogels. These MMP-responsive PEG-hydrogels may thus serve as controlled co-encapsulation system of vascular cells and bioactive factors for in situ regeneration of ischemic tissues. PMID:19500842

  15. Self-Replenishing Vascularized Fouling-Release Surfaces

    DOE PAGES

    Howell, Caitlin; Vu, Thy L.; Lin, Jennifer J.; ...

    2014-08-13

    Inspired by the long-term effectiveness of living antifouling materials, we have developed a method for the selfreplenishment of synthetic biofouling-release surfaces. These surfaces are created by either molding or directly embedding 3D vascular systems into polydimethylsiloxane (PDMS) and filling them with a silicone oil to generate a nontoxic oil-infused material. When replenished with silicone oil from an outside source, these materials are capable of self-lubrication and continuous renewal of the interfacial fouling-release layer. Under accelerated lubricant loss conditions, fully infused vascularized samples retained significantly more lubricant than equivalent nonvascularized controls. Tests of lubricant-infused PDMS in static cultures of the infectiousmore » bacteria Staphylococcus aureus and Escherichia coli as well as the green microalgae Botryococcus braunii, Chlamydomonas reinhardtii, Dunaliella salina, and Nannochloropsis oculata showed a significant reduction in biofilm adhesion compared to PDMS and glass controls containing no lubricant. Further experiments on vascularized versus nonvascularized samples that had been subjected to accelerated lubricant evaporation conditions for up to 48 h showed significantly less biofilm adherence on the vascularized surfaces. These results demonstrate the ability of an embedded lubricant-filled vascular network to improve the longevity of fouling-release surfaces.« less

  16. Scanning electron microscopy observation of vascularization around hydroxyapatite using vascular corrosion casts.

    PubMed

    Chang, C S; Su, C Y; Lin, T C

    1999-01-01

    An intimate relationship exists between the regenerative response of the vascular and osseous elements following hydroxyapatite (HA) implantation. In order to fully comprehend the 3-dimensional vascular architecture around HA, dense HA particles were implanted into the tibiae of dogs. Following healing periods of 2 weeks, 1 month, and 3 months, the tibiae were prepared by the corrosion cast technique. Under scanning electron microscopy (SEM) observation, the characteristic vascular morphology of the HA-implanted cavity was successfully demonstrated. The initial vascularization began in the form of loose sinusoidal capillaries. Many sinusoids formed a complex network by anastomosing with each other. The newly formed vessels extended centripetally from the peripheral cavity wall and from the periosteal surface. Under greater magnification, the tapered vascular sprouting was shown to project into the space that was previously occupied by an HA particle. The presence of vascular sprouting is clearly an important indicator of angiogenesis. Increasing vascularization was demonstrated with time. The presence of vessels in the Haversian's canal indicated the more established vascularization. Almost full vascularization of the HA-implanted cavity was seen 3 months after implantation. The vascular organizational layout of the cavity was also clearly shown in the fractured transverse-sectioned sample. In the control without HA implantation, the central region of the cavity showed a hollow pattern in the initial stage. The vascularization looked like it was collapsing and not fully filling the cavity. However, remarkable differences of the final vascular pattern could not be found between the study and control group after 3-month implantation. The study provides the time-lapsed 3-dimensional vascular changes of the HA-implanted cavity, as well as the value of the corrosion cast technique in examining the bony circulation. Copyright 1999 John Wiley & Sons, Inc.

  17. Increased expression of matrix metalloproteinase-1 in systemic vessels of preeclamptic women: a critical mediator of vascular dysfunction.

    PubMed

    Estrada-Gutierrez, Guadalupe; Cappello, Renato E; Mishra, Nikita; Romero, Roberto; Strauss, Jerome F; Walsh, Scott W

    2011-01-01

    This study was conducted to determine the following: (1) whether matrix metalloproteinase-1 (MMP-1) is increased in systemic vessels of preeclamptic women, (2) whether this increase might be mediated by neutrophils, and (3) whether MMP-1 could be responsible for vascular dysfunction. Omental arteries and plasma were collected from healthy pregnant and preeclamptic women. Omental arteries were evaluated for gene and protein expression of MMP-1, collagen type 1α, tissue inhibitor of metalloproteinase-1, and vascular reactivity to MMP-1. Gene and protein expression levels were also evaluated in human vascular smooth muscle cells (VSMCs) co-cultured with activated neutrophils, reactive oxygen species, or tumor necrosis factor α. Vessel expression of MMP-1 and circulating MMP-1 levels were increased in preeclamptic women, whereas vascular expression of collagen or tissue inhibitor of metalloproteinase-1 were down-regulated or unchanged. In cultured VSMCs, the imbalance in collagen-regulating genes of preeclamptic vessels was reproduced by treatment with neutrophils, tumor necrosis factor α, or reactive oxygen species. Chemotaxis studies with cultured cells revealed that MMP-1 promoted recruitment of neutrophils via vascular smooth muscle release of interleukin-8. Furthermore, MMP-1 induced vasoconstriction via protease-activated receptor-1, whose expression was significantly increased in omental arteries of preeclamptic women and in VSMCs co-cultured with neutrophils. Collectively, these findings disclose a novel role for MMP-1 as a mediator of vasoconstriction and vascular dysfunction in preeclampsia. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  18. Weak Maser Emission of Methyl Formate toward Sagittarius B2(N) in the Green Bank Telescope PRIMOS Survey

    NASA Astrophysics Data System (ADS)

    Faure, A.; Remijan, A. J.; Szalewicz, K.; Wiesenfeld, L.

    2014-03-01

    A non-LTE radiative transfer treatment of cis-methyl formate (HCOOCH3) rotational lines is presented for the first time using a set of theoretical collisional rate coefficients. These coefficients have been computed in the temperature range 5-30 K by combining coupled-channel scattering calculations with a high accuracy potential energy surface for HCOOCH3-He. The results are compared to observations toward the Sagittarius B2(N) molecular cloud using the publicly available PRIMOS survey from the Green Bank Telescope. A total of 49 low-lying transitions of methyl formate, with upper levels below 25 K, are identified. These lines are found to probe a presumably cold (~30 K), moderately dense (~104 cm-3), and extended region surrounding Sgr B2(N). The derived column density of ~4 × 1014 cm-2 is only a factor of ~10 larger than the column density of the trans conformer in the same source. Provided that the two conformers have the same spatial distribution, this result suggests that strongly non-equilibrium processes must be involved in their synthesis. Finally, our calculations show that all detected emission lines with a frequency below 30 GHz are (collisionally pumped) weak masers amplifying the continuum of Sgr B2(N). This result demonstrates the importance and generality of non-LTE effects in the rotational spectra of complex organic molecules at centimeter wavelengths.

  19. Vascular labeling of the head and neck vessels: Technique, advantages and limitations.

    PubMed

    Gálvez, Alba; Caraballo, José-Leonardo; Manzanares-Céspedes, María-Cristina; Valdivia-Gandur, Iván; Figueiredo, Rui; Valmaseda-Castellón, Eduard

    2017-05-01

    Vascular staining techniques have been used to describe the vascular structures of several anatomic areas. However, few reports have described this procedure in the head and neck region. This paper describes a head and neck vascular labeling procedure, and describes some of the technical complications that may occur. Fifteen specimen cadaver heads were prepared. After drying the vascular system, the internal carotid arteries were ligated and a solution with latex and a gelling agent was injected into the internal carotid arteries and external jugular veins. Two different colors were employed to differentiate arteries from veins. A total of 60ml latex was injected into each blood vessel. Subsequently, the specimens were refrigerated at 5°C for a minimum of 24 hours. Finally, a dissection was performed to identify the venous and arterial systems of the maxillofacial region. In most specimens, correct identification of the vascular structures (lingual artery, pterigoyd plexus, and the major palatal arteries, among others) was possible. However, in three heads a major technical problem occurred (the latex remained liquid), making the dissection unfeasible. Other minor complications such as latex obstruction due to the presence of atheromas were found in two further specimens. The vascular labeling technique is a predictable, effective and simple method for analyzing the vascular system of the maxillofacial area in cadaveric studies, including vessels of reduced diameter or with an intraosseous course. This procedure can be especially useful to teach vascular anatomy to dental students and postgraduate residents. Key words: Blood vessels, vascular casting, vascular labeling, head and neck arteries, carotid arteries, jugular veins.

  20. Dynamic Measurement of Tumor Vascular Permeability and Perfusion using a Hybrid System for Simultaneous Magnetic Resonance and Fluorescence Imaging.

    PubMed

    Ren, Wuwei; Elmer, Andreas; Buehlmann, David; Augath, Mark-Aurel; Vats, Divya; Ripoll, Jorge; Rudin, Markus

    2016-04-01

    Assessing tumor vascular features including permeability and perfusion is essential for diagnostic and therapeutic purposes. The aim of this study was to compare fluorescence and magnetic resonance imaging (MRI)-based vascular readouts in subcutaneously implanted tumors in mice by simultaneous dynamic measurement of tracer uptake using a hybrid fluorescence molecular tomography (FMT)/MRI system. Vascular permeability was measured using a mixture of extravascular imaging agents, GdDOTA and the dye Cy5.5, and perfusion using a mixture of intravascular agents, Endorem and a fluorescent probe (Angiosense). Dynamic fluorescence reflectance imaging (dFRI) was integrated into the hybrid system for high temporal resolution. Excellent correspondence between uptake curves of Cy5.5/GdDOTA and Endorem/Angiosense has been found with correlation coefficients R > 0.98. The two modalities revealed good agreement regarding permeability coefficients and centers-of-gravity of the imaging agent distribution. The FMT/dFRI protocol presented is able to accurately map physiological processes and poses an attractive alternative to MRI for characterizing tumor neoangiogenesis.

  1. [Experimental study of angiography using vascular interventional robot-2(VIR-2)].

    PubMed

    Tian, Zeng-min; Lu, Wang-sheng; Liu, Da; Wang, Da-ming; Guo, Shu-xiang; Xu, Wu-yi; Jia, Bo; Zhao, De-peng; Liu, Bo; Gao, Bao-feng

    2012-06-01

    To verify the feasibility and safety of new vascular interventional robot system used in vascular interventional procedures. Vascular interventional robot type-2 (VIR-2) included master-slave parts of body propulsion system, image navigation systems and force feedback system, the catheter movement could achieve under automatic control and navigation, force feedback was integrated real-time, followed by in vitro pre-test in vascular model and cerebral angiography in dog. Surgeon controlled vascular interventional robot remotely, the catheter was inserted into the intended target, the catheter positioning error and the operation time would be evaluated. In vitro pre-test and animal experiment went well; the catheter can enter any branch of vascular. Catheter positioning error was less than 1 mm. The angiography operation in animal was carried out smoothly without complication; the success rate of the operation was 100% and the entire experiment took 26 and 30 minutes, efficiency was slightly improved compared with the VIR-1, and the time what staff exposed to the DSA machine was 0 minute. The resistance of force sensor can be displayed to the operator to provide a security guarantee for the operation. No surgical complications. VIR-2 is safe and feasible, and can achieve the catheter remote operation and angiography; the master-slave system meets the characteristics of traditional procedure. The three-dimensional image can guide the operation more smoothly; force feedback device provides remote real-time haptic information to provide security for the operation.

  2. Quantitative analysis of vascular parameters for micro-CT imaging of vascular networks with multi-resolution.

    PubMed

    Zhao, Fengjun; Liang, Jimin; Chen, Xueli; Liu, Junting; Chen, Dongmei; Yang, Xiang; Tian, Jie

    2016-03-01

    Previous studies showed that all the vascular parameters from both the morphological and topological parameters were affected with the altering of imaging resolutions. However, neither the sensitivity analysis of the vascular parameters at multiple resolutions nor the distinguishability estimation of vascular parameters from different data groups has been discussed. In this paper, we proposed a quantitative analysis method of vascular parameters for vascular networks of multi-resolution, by analyzing the sensitivity of vascular parameters at multiple resolutions and estimating the distinguishability of vascular parameters from different data groups. Combining the sensitivity and distinguishability, we designed a hybrid formulation to estimate the integrated performance of vascular parameters in a multi-resolution framework. Among the vascular parameters, degree of anisotropy and junction degree were two insensitive parameters that were nearly irrelevant with resolution degradation; vascular area, connectivity density, vascular length, vascular junction and segment number were five parameters that could better distinguish the vascular networks from different groups and abide by the ground truth. Vascular area, connectivity density, vascular length and segment number not only were insensitive to multi-resolution but could also better distinguish vascular networks from different groups, which provided guidance for the quantification of the vascular networks in multi-resolution frameworks.

  3. Contact area affects frequency-dependent responses to vibration in the peripheral vascular and sensorineural systems.

    PubMed

    Krajnak, Kristine; Miller, G R; Waugh, Stacey

    2018-01-01

    Repetitive exposure to hand-transmitted vibration is associated with development of peripheral vascular and sensorineural dysfunctions. These disorders and symptoms associated with it are referred to as hand-arm vibration syndrome (HAVS). Although the symptoms of the disorder have been well characterized, the etiology and contribution of various exposure factors to development of the dysfunctions are not well understood. Previous studies performed using a rat-tail model of vibration demonstrated that vascular and peripheral nervous system adverse effects of vibration are frequency-dependent, with vibration frequencies at or near the resonant frequency producing the most severe injury. However, in these investigations, the amplitude of the exposed tissue was greater than amplitude typically noted in human fingers. To determine how contact with vibrating source and amplitude of the biodynamic response of the tissue affects the risk of injury occurring, this study compared the influence of frequency using different levels of restraint to assess how maintaining contact of the tail with vibrating source affects the transmission of vibration. Data demonstrated that for the most part, increasing the contact of the tail with the platform by restraining it with additional straps resulted in an enhancement in transmission of vibration signal and elevation in factors associated with vascular and peripheral nerve injury. In addition, there were also frequency-dependent effects, with exposure at 250 Hz generating greater effects than vibration at 62.5 Hz. These observations are consistent with studies in humans demonstrating that greater contact and exposure to frequencies near the resonant frequency pose the highest risk for generating peripheral vascular and sensorineural dysfunction.

  4. The use of microtechnology and nanotechnology in fabricating vascularized tissues.

    PubMed

    Obregón, Raquel; Ramón-Azcón, Javier; Ahadian, Samad; Shiku, Hitoshi; Bae, Hojae; Ramalingam, Murugan; Matsue, Tomokazu

    2014-01-01

    Tissue engineering (TE) is a multidisciplinary research area that combines medicine, biology, and material science. In recent decades, microtechnology and nanotechnology have also been gradually integrated into this field and have become essential components of TE research. Tissues and complex organs in the body depend on a branched blood vessel system. One of the main objectives for TE researchers is to replicate this vessel system and obtain functional vascularized structures within engineered tissues or organs. With the help of new nanotechnology and microtechnology, significant progress has been made. Achievements include the design of nanoscale-level scaffolds with new functionalities, development of integrated and rapid nanotechnology methods for biofabrication of vascular tissues, discovery of new composite materials to direct differentiation of stem and inducible pluripotent stem cells into the vascular phenotype. Although numerous challenges to replicating vascularized tissue for clinical uses remain, the combination of these new advances has yielded new tools for producing functional vascular tissues in the near future.

  5. Oral vascular malformations: laser treatment and management

    NASA Astrophysics Data System (ADS)

    Romeo, U.; Rocchetti, F.; Gaimari, G.; Tenore, G.; Palaia, G.; Lo Giudice, G.

    2016-03-01

    Vascular malformations are a very heterogeneous group of circulatory system's diseases that can involve different kind of vessels: arterial, venous or lymphatic ones. Many treatments, such as conventional surgery, embolization, steroid therapy and laser therapy, are available for vascular lesions. The laser approach relies more therapeutic techniques: the transmucosal thermophotocoagulation, intralesional photocoagulation, the excisional biopsy. Today laser is demonstrated to be the gold standard technique to treat vascular lesions that allows a safe and efficient treatment and a lower post-operative healing time. The only disadvantage is the risk of carbonization that could be avoided by using the multiple-spot single pulsed wave technique.

  6. Assessment of risk of peripheral vascular disease and vascular care capacity in low- and middle-income countries.

    PubMed

    Gyedu, A; Stewart, B T; Nakua, E; Quansah, R; Donkor, P; Mock, C; Hardy, M; Yangni-Angate, K H

    2016-01-01

    This study aimed to describe national peripheral vascular disease (PVD) risk and health burden, and vascular care capacity in Ghana. The gap between PVD burden and vascular care capacity in low- and middle-income countries was defined, and capacity improvement priorities were identified. Data to estimate PVD risk factor burden were obtained from the World Health Organization Study on Global Ageing and Adult Health (SAGE), Ghana, and the Institute of Health Metrics and Evaluation Global Burden of Disease (IHME GBD) database. In addition, a novel nationwide assessment of vascular care capacity was performed, with 20 vascular care items assessed at 40 hospitals in Ghana. Factors contributing to specific item deficiency were described. From the SAGE database, there were 4305 respondents aged at least 50 years with data to estimate PVD risk. Of these, 57·4 per cent were at moderate to risk high of PVD with at least three risk factors; extrapolating nationally, the estimate was 1 654 557 people. Based on IHME GBD data, the estimated disability-adjusted life-years incurred from PVD increased fivefold from 1990 to 2010 (from 6·3 to 31·7 per 100 000 persons respectively). Vascular care capacity assessment demonstrated marked deficiencies in items for diagnosis, and in perioperative and vascular surgical care. Deficiencies were most often due to absence of equipment, lack of training and technology breakage. Risk factor reduction and management as well as optimization of current resources are paramount to avoid the large burden of PVD falling on healthcare systems in low- and middle-income countries. These countries are not well equipped to handle vascular surgical care, and rapid development of such capacity would be difficult and expensive. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

  7. Stem cell function during plant vascular development

    PubMed Central

    Miyashima, Shunsuke; Sebastian, Jose; Lee, Ji-Young; Helariutta, Yka

    2013-01-01

    The plant vascular system, composed of xylem and phloem, evolved to connect plant organs and transport various molecules between them. During the post-embryonic growth, these conductive tissues constitutively form from cells that are derived from a lateral meristem, commonly called procambium and cambium. Procambium/cambium contains pluripotent stem cells and provides a microenvironment that maintains the stem cell population. Because vascular plants continue to form new tissues and organs throughout their life cycle, the formation and maintenance of stem cells are crucial for plant growth and development. In this decade, there has been considerable progress in understanding the molecular control of the organization and maintenance of stem cells in vascular plants. Noticeable advance has been made in elucidating the role of transcription factors and major plant hormones in stem cell maintenance and vascular tissue differentiation. These studies suggest the shared regulatory mechanisms among various types of plant stem cell pools. In this review, we focus on two aspects of stem cell function in the vascular cambium, cell proliferation and cell differentiation. PMID:23169537

  8. Theoretical models for coronary vascular biomechanics: Progress & challenges

    PubMed Central

    Waters, Sarah L.; Alastruey, Jordi; Beard, Daniel A.; Bovendeerd, Peter H.M.; Davies, Peter F.; Jayaraman, Girija; Jensen, Oliver E.; Lee, Jack; Parker, Kim H.; Popel, Aleksander S.; Secomb, Timothy W.; Siebes, Maria; Sherwin, Spencer J.; Shipley, Rebecca J.; Smith, Nicolas P.; van de Vosse, Frans N.

    2013-01-01

    A key aim of the cardiac Physiome Project is to develop theoretical models to simulate the functional behaviour of the heart under physiological and pathophysiological conditions. Heart function is critically dependent on the delivery of an adequate blood supply to the myocardium via the coronary vasculature. Key to this critical function of the coronary vasculature is system dynamics that emerge via the interactions of the numerous constituent components at a range of spatial and temporal scales. Here, we focus on several components for which theoretical approaches can be applied, including vascular structure and mechanics, blood flow and mass transport, flow regulation, angiogenesis and vascular remodelling, and vascular cellular mechanics. For each component, we summarise the current state of the art in model development, and discuss areas requiring further research. We highlight the major challenges associated with integrating the component models to develop a computational tool that can ultimately be used to simulate the responses of the coronary vascular system to changing demands and to diseases and therapies. PMID:21040741

  9. Microvascular dysfunction with increased vascular leakage response in mice systemically exposed to arsenic.

    PubMed

    Chen, Shih-Chieh; Huang, Shin-Yin; Lu, Chi-Yu; Hsu, Ya-Hung; Wang, Dean-Chuan

    2014-09-01

    The mechanisms underlying cardiovascular disease induced by arsenic exposure are not completely understood. The objectives of this study were to investigate whether arsenic-fed mice have an increased vascular leakage response to vasoactive agents and whether enhanced type-2 protein phosphatase (PP2A) activity is involved in mustard oil-induced leakage. ICR mice were fed water or sodium arsenite (20 mg/kg) for 4 or 8 weeks. The leakage response to vasoactive agents was quantified using the Evans blue (EB) technique or vascular labeling with carbon particles. Increased EB leakage and high density of carbon-labeled microvessels were detected in arsenic-fed mice treated with mustard oil. Histamine induced significantly higher vascular leakage in arsenic-fed mice than in water-fed mice. Pretreatment with the PP2A inhibitor okadaic acid or the neurokinin 1 receptor (NK1R) blocker RP67580 significantly reduced mustard oil-induced vascular leakage in arsenic-fed mice. The protein levels of PP2Ac and NK1R were similar in both groups. PP2A activity was significantly higher in the arsenic-fed mice compared with the control group. These findings indicate that microvessels generally respond to vasoactive agents, and that the increased PP2A activity is involved in mustard oil-induced vascular leakage in arsenic-fed mice. Arsenic may initiate endothelial dysfunction, resulting in vascular leakage in response to vasoactive agents.

  10. Vascular ring

    MedlinePlus

    ... with aberrant subclavian and left ligamentum ateriosus; Congenital heart defect - vascular ring; Birth defect heart - vascular ring ... accounts for less than 1% of all congenital heart problems. The condition occurs as often in males ...

  11. BK Channels in the Vascular System.

    PubMed

    Krishnamoorthy-Natarajan, G; Koide, M

    2016-01-01

    Autoregulation of blood flow is essential for the preservation of organ function to ensure continuous supply of oxygen and essential nutrients and removal of metabolic waste. This is achieved by controlling the diameter of muscular arteries and arterioles that exhibit a myogenic response to changes in arterial blood pressure, nerve activity and tissue metabolism. Large-conductance voltage and Ca(2+)-dependent K(+) channels (BK channels), expressed exclusively in smooth muscle cells (SMCs) in the vascular wall of healthy arteries, play a critical role in regulating the myogenic response. Activation of BK channels by intracellular, local, and transient ryanodine receptor-mediated "Ca(2+) sparks," provides a hyperpolarizing influence on the SMC membrane potential thereby decreasing the activity of voltage-dependent Ca(2+) channels and limiting Ca(2+) influx to promote SMC relaxation and vasodilation. The BK channel α subunit, a large tetrameric protein with each monomer consisting of seven-transmembrane domains, a long intracellular C-terminal tail and an extracellular N-terminus, associates with the β1 and γ subunits in vascular SMCs. The BK channel is regulated by factors originating within the SMC or from the endothelium, perivascular nerves and circulating blood, that significantly alter channel gating properties, Ca(2+) sensitivity and expression of the α and/or β1 subunit. The BK channel thus serves as a central receiving dock that relays the effects of the changes in several such concomitant autocrine and paracrine factors and influences cardiovascular health. This chapter describes the primary mechanism of regulation of myogenic response by BK channels and the alterations to this mechanism wrought by different vasoactive mediators. © 2016 Elsevier Inc. All rights reserved.

  12. Medical expert system for assessment of coronary heart disease destabilization based on the analysis of the level of soluble vascular adhesion molecules

    NASA Astrophysics Data System (ADS)

    Serkova, Valentina K.; Pavlov, Sergey V.; Romanava, Valentina A.; Monastyrskiy, Yuriy I.; Ziepko, Sergey M.; Kuzminova, Nanaliya V.; Wójcik, Waldemar; DzierŻak, RóŻa; Kalizhanova, Aliya; Kashaganova, Gulzhan

    2017-08-01

    Theoretical and practical substantiation of the possibility of the using the level of soluble vascular adhesion molecules (sVCAM) is performed. Expert system for the assessment of coronary heart disease (CHD) destabilization on the base of the analysis of soluble vascular adhesion molecules level is developed. Correlation between the increase of VCAM level and C-reactive protein (CRP) in patients with different variants of CHD progression is established. Association of chronic nonspecific vascular inflammation activation and CHD destabilization is shown. The expedience of parallel determination of sVCAM and CRP levels for diagnostics of CHD destabilization and forecast elaboration is noted.

  13. Lean manufacturing and Toyota Production System terminology applied to the procurement of vascular stents in interventional radiology.

    PubMed

    de Bucourt, Maximilian; Busse, Reinhard; Güttler, Felix; Wintzer, Christian; Collettini, Federico; Kloeters, Christian; Hamm, Bernd; Teichgräber, Ulf K

    2011-08-01

    OBJECTIVES: To apply the economic terminology of lean manufacturing and the Toyota Production System to the procurement of vascular stents in interventional radiology. METHODS: The economic- and process-driven terminology of lean manufacturing and the Toyota Production System is first presented, including information and product flow as well as value stream mapping (VSM), and then applied to an interdisciplinary setting of physicians, nurses and technicians from different medical departments to identify wastes in the process of endovascular stent procurement in interventional radiology. RESULTS: Using the so-called seven wastes approach of the Toyota Production System (waste of overproducing, waiting, transport, processing, inventory, motion and waste of defects and spoilage) as well as further waste characteristics (gross waste, process and method waste, and micro waste), wastes in the process of endovascular stent procurement in interventional radiology were identified and eliminated to create an overall smoother process from the procurement as well as from the medical perspective. CONCLUSION: Economic terminology of lean manufacturing and the Toyota Production System, especially VSM, can be used to visualise and better understand processes in the procurement of vascular stents in interventional radiology from an economic point of view.

  14. Hemodynamic comparison of mild and severe preeclampsia: concept of stroke systemic vascular resistance index.

    PubMed

    Scardo, J; Kiser, R; Dillon, A; Brost, B; Newman, R

    1996-01-01

    Our purpose was to compare baseline hemodynamic parameters of mild and severe preeclampsia. Patients admitted to the Medical University Labor and Delivery Unit with the diagnosis of preeclampsia who had not received prior antihypertensive or magnesium sulfate therapy were recruited for noninvasive hemodynamic monitoring with thoracic electrical bioimpedance. After stabilization in the lateral recumbent position, hemodynamic monitoring was begun. Baseline hemodynamic parameters, mean arterial pressure (MAP), heart rate (HR), systemic vascular resistance index (SVRI), cardiac index (CI), and stroke index (SI) were recorded. Stroke systemic vascular resistance index (SSVRI), the resistance imposed by vasculature on each beat of the heart, was calculated for each patient by multiplying SVRI by HR. For statistical analysis, unpaired Student's t-tests (two-tailed) were utilized (P < 0.01). Forty-one preeclamptic patients (20 mild, 21 severe) were enrolled. Mean gestational age of severe patients was 32.2 +/- 4.0 and of mild patients was 37.0 +/- 3.5. MAP, SBP, diastolic blood pressure, HR, and SSVRI were higher in the severe group. SVRI, CI, cardiac output, and SI did not differ significantly between groups. Severe preclampsia appears to be a more intensely vasoconstricted state than mild preeclampsia. Although CI is inversely proportional to SVRI, increased HR in severe preeclampsia prevents this expected decrease in cardiac output.

  15. Hand biometric recognition based on fused hand geometry and vascular patterns.

    PubMed

    Park, GiTae; Kim, Soowon

    2013-02-28

    A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%.

  16. VEGF signaling inside vascular endothelial cells and beyond

    PubMed Central

    Eichmann, Anne; Simons, Michael

    2014-01-01

    Vascular endothelial growth factor-A (VEGF-A) has long been recognized as the key regulator of vascular development and function in health and disease. VEGF is a secreted polypeptide that binds to transmembrane tyrosine kinase VEGF receptors on the plasma membrane, inducing their dimerization, activation and assembly of a membrane-proximal signaling complex. Recent studies have revealed that many key events of VEGFR signaling occur inside the endothelial cell and are regulated by endosomal receptor trafficking. Plasma membrane VEGFR interacting molecules, including vascular guidance receptors Neuropilins and Ephrins also regulate VEGFR endocytosis and trafficking. VEGF signaling is increasingly recognized for its roles outside of the vascular system, notably during neural development, and blood vessels regulate epithelial branching morphogenesis. We review here recent advances in our understanding of VEGF signaling and its biological roles. PMID:22366328

  17. 2011 Vascular Research Initiatives Conference: basic foundations of translational research in vascular disease.

    PubMed

    Ziegler, Kenneth R; Dardik, Alan

    2011-07-01

    The Vascular Research Initiatives Conference (VRIC) is an annual conference organized by the Society for Vascular Surgery (SVS). The 2011 VRIC was held in Chicago (IL, USA) to precede and coincide with the first day of the meeting of the Council on Arteriosclerosis, Thrombosis and Vascular Biology (ATVB) of the American Heart Association. The event is designed to present world class vascular research results, encourage collaboration between vascular surgeons and basic scientists in related disciplines, as well as to stimulate interest in research among aspiring academic vascular surgeons. The 2011 VRIC featured plenary sessions addressing peripheral arterial disease, vascular endothelium and thrombosis, aneurysms, and stem cells and tissue engineering. Recipients of the SVS partner grants with the National Institutes of Health K08 awardees presented their progress reports, and keynote addresses were given by Linda Graham and Frank LoGerfo.

  18. Salicylic acid prevents Trichoderma harzianum from entering the vascular system of roots.

    PubMed

    Alonso-Ramírez, Ana; Poveda, Jorge; Martín, Ignacio; Hermosa, Rosa; Monte, Enrique; Nicolás, Carlos

    2014-10-01

    Trichoderma is a soil-borne fungal genus that includes species with a significant impact on agriculture and industrial processes. Some Trichoderma strains exert beneficial effects in plants through root colonization, although little is known about how this interaction takes place. To better understand this process, the root colonization of wild-type Arabidopsis and the salicylic acid (SA)-impaired mutant sid2 by a green fluorescent protein (GFP)-marked Trichoderma harzianum strain was followed under confocal microscopy. Trichoderma harzianum GFP22 was able to penetrate the vascular tissue of the sid2 mutant because of the absence of callose deposition in the cell wall of root cells. In addition, a higher colonization of sid2 roots by GFP22 compared with that in Arabidopsis wild-type roots was detected by real-time polymerase chain reaction. These results, together with differences in the expression levels of plant defence genes in the roots of both interactions, support a key role for SA in Trichoderma early root colonization stages. We observed that, without the support of SA, plants were unable to prevent the arrival of the fungus in the vascular system and its spread into aerial parts, leading to later collapse. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  19. Protein Kinase C as Regulator of Vascular Smooth Muscle Function and Potential Target in Vascular Disorders.

    PubMed

    Ringvold, H C; Khalil, R A

    2017-01-01

    Vascular smooth muscle (VSM) plays an important role in maintaining vascular tone. In addition to Ca 2+ -dependent myosin light chain (MLC) phosphorylation, protein kinase C (PKC) is a major regulator of VSM function. PKC is a family of conventional Ca 2+ -dependent α, β, and γ, novel Ca 2+ -independent δ, ɛ, θ, and η, and atypical ξ, and ι/λ isoforms. Inactive PKC is mainly cytosolic, and upon activation it undergoes phosphorylation, maturation, and translocation to the surface membrane, the nucleus, endoplasmic reticulum, and other cell organelles; a process facilitated by scaffold proteins such as RACKs. Activated PKC phosphorylates different substrates including ion channels, pumps, and nuclear proteins. PKC also phosphorylates CPI-17 leading to inhibition of MLC phosphatase, increased MLC phosphorylation, and enhanced VSM contraction. PKC could also initiate a cascade of protein kinases leading to phosphorylation of the actin-binding proteins calponin and caldesmon, increased actin-myosin interaction, and VSM contraction. Increased PKC activity has been associated with vascular disorders including ischemia-reperfusion injury, coronary artery disease, hypertension, and diabetic vasculopathy. PKC inhibitors could test the role of PKC in different systems and could reduce PKC hyperactivity in vascular disorders. First-generation PKC inhibitors such as staurosporine and chelerythrine are not very specific. Isoform-specific PKC inhibitors such as ruboxistaurin have been tested in clinical trials. Target delivery of PKC pseudosubstrate inhibitory peptides and PKC siRNA may be useful in localized vascular disease. Further studies of PKC and its role in VSM should help design isoform-specific PKC modulators that are experimentally potent and clinically safe to target PKC in vascular disease. © 2017 Elsevier Inc. All rights reserved.

  20. Consensus recommendations for essential vascular care in low- and middle-income countries.

    PubMed

    Stewart, Barclay T; Gyedu, Adam; Giannou, Christos; Mishra, Brijesh; Rich, Norman; Wren, Sherry M; Mock, Charles; Kushner, Adam L

    2016-12-01

    Many low- and middle-income countries (LMICs) are ill equipped to care for the large and growing burden of vascular conditions. We aimed to develop essential vascular care recommendations that would be feasible for implementation at nearly every setting worldwide, regardless of national income. The normative Delphi method was used to achieve consensus on essential vascular care resources among 27 experts in multiple areas of vascular care and public health as well as with experience in LMIC health care. Five anonymous, iterative rounds of survey with controlled feedback and a statistical response were used to reach consensus on essential vascular care resources. The matrices provide recommendations for 92 vascular care resources at each of the four levels of care in most LMICs, comprising primary health centers and first-level, referral, and tertiary hospitals. The recommendations include essential and desirable resources and encompass the following categories: screening, counseling, and evaluation; diagnostics; medical care; surgical care; equipment and supplies; and medications. The resources recommended have the potential to improve the ability of LMIC health care systems to respond to the large and growing burden of vascular conditions. Many of these resources can be provided with thoughtful planning and organization, without significant increases in cost. However, the resources must be incorporated into a framework that includes surveillance of vascular conditions, monitoring and evaluation of vascular capacity and care, a well functioning prehospital and interhospital transport system, and vascular training for existing and future health care providers. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  1. [Clinical significance of MESS scoring system in the treatment of fractures of lower limb combined with vascular injuries].

    PubMed

    Zhou, Fei-Ya; Guo, Xiao-Shan; Gao, Wei-Yang; Chen, Xing-Long; Li, Zhi-Jie; Jiang, Liang-Fu

    2010-06-01

    To study the clinical significance of MESS scoring system in the treatment of fractures of lower limb combined with vascular injuries, and to evaluate its reliance. From March 2006 to March 2008, 28 patients with fractures of lower limb combined with vascular injuries were graded by MESS scoring system. There were 17 patients were male and 11 patients were female, ranging in age from 23 to 53 years, averaged 38 years. Seventeen patients had fractures at the superior segment of tibia and fibia, 7 patients had fractures at the inferior segment of femur, and other 4 patients had dislocation of knee joint. Among the patients, 18 patients had MESS scores more than 7.0 point, in which 13 patients were treated with one-stage amputation, 5 patients were treated with two-stage amputation; the other 10 patients had the MESS scores less than 7.0 point, and were treated with open reduction and internal fixation, in which 8 patients were treated with transplantation of great saphenous vein to repair blood vessles, and 2 patients were treated with vascular end to end anastomosis. Among the patients, including 18 patients whose MESS scores more than 7.0 point were treated with one-stage or two-stage amputation, and 10 patients whose MESS scores less than 7.0 point were treated with limb salvage operations, all the limbs survived. During the follow-up period (ranged from 0.5 to 1 year, the movement and sensory function of the limbs recovered well. MESS is a simple and reliable tool to determine the proper strategy for the patients suffering from vascular injuries with fractures.

  2. Vinpocetine suppresses pathological vascular remodeling by inhibiting vascular smooth muscle cell proliferation and migration.

    PubMed

    Cai, Yujun; Knight, Walter E; Guo, Shujie; Li, Jian-Dong; Knight, Peter A; Yan, Chen

    2012-11-01

    Abnormal vascular smooth muscle cell (SMC) activation is associated with various vascular disorders such as atherosclerosis, in-stent restenosis, vein graft disease, and transplantation-associated vasculopathy. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. However, its role in pathological vascular remodeling remains unexplored. Herein, we show that systemic administration of vinpocetine significantly reduced neointimal formation in carotid arteries after ligation injury. Vinpocetine also markedly decreased spontaneous remodeling of human saphenous vein explants in ex vivo culture. In cultured SMCs, vinpocetine dose-dependently suppressed cell proliferation and caused G1-phase cell cycle arrest, which is associated with a decrease in cyclin D1 and an increase in p27Kip1 levels. In addition, vinpocetine dose-dependently inhibited platelet-derived growth factor (PDGF)-stimulated SMC migration as determined by the two-dimensional migration assays and three-dimensional aortic medial explant invasive assay. Moreover, vinpocetine significantly reduced PDGF-induced type I collagen and fibronectin expression. It is noteworthy that PDGF-stimulated phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2), but not protein kinase B, was specifically inhibited by vinpocetine. Vinpocetine powerfully attenuated intracellular reactive oxidative species (ROS) production, which largely mediates the inhibitory effects of vinpocetine on ERK1/2 activation and SMC growth. Taken together, our results reveal a novel function of vinpocetine in attenuating neointimal hyperplasia and pathological vascular remodeling, at least partially through suppressing ROS production and ERK1/2 activation in SMCs. Given the safety profile of vinpocetine, this study provides insight into the therapeutic potential of vinpocetine in proliferative vascular disorders.

  3. Vinpocetine Suppresses Pathological Vascular Remodeling by Inhibiting Vascular Smooth Muscle Cell Proliferation and Migration

    PubMed Central

    Cai, Yujun; Knight, Walter E.; Guo, Shujie; Li, Jian-Dong; Knight, Peter A.

    2012-01-01

    Abnormal vascular smooth muscle cell (SMC) activation is associated with various vascular disorders such as atherosclerosis, in-stent restenosis, vein graft disease, and transplantation-associated vasculopathy. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. However, its role in pathological vascular remodeling remains unexplored. Herein, we show that systemic administration of vinpocetine significantly reduced neointimal formation in carotid arteries after ligation injury. Vinpocetine also markedly decreased spontaneous remodeling of human saphenous vein explants in ex vivo culture. In cultured SMCs, vinpocetine dose-dependently suppressed cell proliferation and caused G1-phase cell cycle arrest, which is associated with a decrease in cyclin D1 and an increase in p27Kip1 levels. In addition, vinpocetine dose-dependently inhibited platelet-derived growth factor (PDGF)-stimulated SMC migration as determined by the two-dimensional migration assays and three-dimensional aortic medial explant invasive assay. Moreover, vinpocetine significantly reduced PDGF-induced type I collagen and fibronectin expression. It is noteworthy that PDGF-stimulated phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2), but not protein kinase B, was specifically inhibited by vinpocetine. Vinpocetine powerfully attenuated intracellular reactive oxidative species (ROS) production, which largely mediates the inhibitory effects of vinpocetine on ERK1/2 activation and SMC growth. Taken together, our results reveal a novel function of vinpocetine in attenuating neointimal hyperplasia and pathological vascular remodeling, at least partially through suppressing ROS production and ERK1/2 activation in SMCs. Given the safety profile of vinpocetine, this study provides insight into the therapeutic potential of vinpocetine in proliferative vascular disorders. PMID:22915768

  4. Weak maser emission of methyl formate toward Sagittarius B2(N) in the green bank telescope PRIMOS survey

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Faure, A.; Wiesenfeld, L.; Remijan, A. J.

    A non-LTE radiative transfer treatment of cis-methyl formate (HCOOCH{sub 3}) rotational lines is presented for the first time using a set of theoretical collisional rate coefficients. These coefficients have been computed in the temperature range 5-30 K by combining coupled-channel scattering calculations with a high accuracy potential energy surface for HCOOCH{sub 3}-He. The results are compared to observations toward the Sagittarius B2(N) molecular cloud using the publicly available PRIMOS survey from the Green Bank Telescope. A total of 49 low-lying transitions of methyl formate, with upper levels below 25 K, are identified. These lines are found to probe a presumablymore » cold (∼30 K), moderately dense (∼10{sup 4} cm{sup –3}), and extended region surrounding Sgr B2(N). The derived column density of ∼4 × 10{sup 14} cm{sup –2} is only a factor of ∼10 larger than the column density of the trans conformer in the same source. Provided that the two conformers have the same spatial distribution, this result suggests that strongly non-equilibrium processes must be involved in their synthesis. Finally, our calculations show that all detected emission lines with a frequency below 30 GHz are (collisionally pumped) weak masers amplifying the continuum of Sgr B2(N). This result demonstrates the importance and generality of non-LTE effects in the rotational spectra of complex organic molecules at centimeter wavelengths.« less

  5. Application of vascular aquatic plants for pollution removal, energy and food production in a biological system

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Barlow, R. M.; Mcdonald, R. C.

    1975-01-01

    Vascular aquatic plants such as water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb., when utilized in a controlled biological system (including a regular program of harvesting to achieve maximum growth and pollution removal efficiency), may represent a remarkably efficient and inexpensive filtration and disposal system for toxic materials and sewage released into waters near urban and industrial areas. The harvested and processed plant materials are sources of energy, fertilizer, animal feed, and human food. Such a system has industrial, municipal, and agricultural applications.

  6. Application of vascular aquatic plants for pollution removal, energy, and food production in a biological system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wolverton, B.C.; Barlow, R.M.; Mcdonald, R.C.

    1975-05-12

    Vascular aquatic plants such as water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb., when utilized in a controlled biological system (including a regular program of harvesting to achieve maximum growth and pollution removal efficiency), may represent a remarkably efficient and inexpensive filtration and disposal system for toxic materials and sewage released into waters near urban and industrial areas. The harvested and processed plant materials are sources of energy, fertilizer, animal feed, and human food. Such a system has industrial, municipal, and agricultural applications. (Author) (GRA)

  7. Vasoregression: A Shared Vascular Pathology Underlying Macrovascular And Microvascular Pathologies?

    PubMed Central

    Gupta, Akanksha

    2015-01-01

    Abstract Vasoregression is a common phenomenon underlying physiological vessel development as well as pathological microvascular diseases leading to peripheral neuropathy, nephropathy, and vascular oculopathies. In this review, we describe the hallmarks and pathways of vasoregression. We argue here that there is a parallel between characteristic features of vasoregression in the ocular microvessels and atherosclerosis in the larger vessels. Shared molecular pathways and molecular effectors in the two conditions are outlined, thus highlighting the possible systemic causes of local vascular diseases. Our review gives us a system-wide insight into factors leading to multiple synchronous vascular diseases. Because shared molecular pathways might usefully address the diagnostic and therapeutic needs of multiple common complex diseases, the literature analysis presented here is of broad interest to readership in integrative biology, rational drug development and systems medicine. PMID:26669709

  8. Whole-mount Confocal Microscopy for Adult Ear Skin: A Model System to Study Neuro-vascular Branching Morphogenesis and Immune Cell Distribution.

    PubMed

    Yamazaki, Tomoko; Li, Wenling; Mukouyama, Yoh-Suke

    2018-03-29

    Here, we present a protocol of a whole-mount adult ear skin imaging technique to study comprehensive three-dimensional neuro-vascular branching morphogenesis and patterning, as well as immune cell distribution at a cellular level. The analysis of peripheral nerve and blood vessel anatomical structures in adult tissues provides some insights into the understanding of functional neuro-vascular wiring and neuro-vascular degeneration in pathological conditions such as wound healing. As a highly informative model system, we have focused our studies on adult ear skin, which is readily accessible for dissection. Our simple and reproducible protocol provides an accurate depiction of the cellular components in the entire skin, such as peripheral nerves (sensory axons, sympathetic axons, and Schwann cells), blood vessels (endothelial cells and vascular smooth muscle cells), and inflammatory cells. We believe this protocol will pave the way to investigate morphological abnormalities in peripheral nerves and blood vessels as well as the inflammation in the adult ear skin under different pathological conditions.

  9. Hand Biometric Recognition Based on Fused Hand Geometry and Vascular Patterns

    PubMed Central

    Park, GiTae; Kim, Soowon

    2013-01-01

    A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%. PMID:23449119

  10. HLA-DRB1*04/*13 alleles are associated with vascular disease and antiphospholipid antibodies in systemic lupus erythematosus.

    PubMed

    Lundström, Emeli; Gustafsson, Johanna T; Jönsen, Andreas; Leonard, Dag; Zickert, Agneta; Elvin, Kerstin; Sturfelt, Gunnar; Nordmark, Gunnel; Bengtsson, Anders A; Sundin, Ulf; Källberg, Henrik; Sandling, Johanna K; Syvänen, Ann-Christine; Klareskog, Lars; Gunnarsson, Iva; Rönnblom, Lars; Padyukov, Leonid; Svenungsson, Elisabet

    2013-06-01

    Vascular disease is common in systemic lupus erythematosus (SLE) and patients with antiphospholipid antibodies (aPL) are at high risk to develop arterial and venous thrombosis. Since HLA class II genotypes have been linked to the presence of pro-thrombotic aPL, we investigated the relationship between HLA-DRB1 alleles, aPL and vascular events in SLE patients. 665 SLE patients of Caucasian origin and 1403 controls were included. Previous manifestations of ischaemic heart disease, ischaemic cerebrovascular disease (ICVD) and venous thromboembolism (together referred to as any vascular events (AVE)) were tabulated. aPL were measured with ELISA. Two-digit HLA-DRB1 typing was performed by sequence-specific primer-PCR. HLA-DRB1*04 was more frequent among SLE patients with ICVD compared to unaffected patients. This association remained after adjustment for known traditional cardiovascular risk factors. HLA-DRB1*13 was associated with AVE. All measured specificities of aPL-cardiolipin IgG and IgM, β2-glycoprotein-1 IgG, prothrombin (PT) IgG and a positive lupus anticoagulant test were associated with HLA-DRB1*04-while HLA-DRB1*13 was associated with IgG antibodies (β2-glycoprotein-1, cardiolipin and PT). In patients with the combined risk alleles, HLA-DRB1*04/*13, there was a significant additive interaction for the outcomes AVE and ICVD. The HLA-DRB1*04 and HLA-DRB1*13 alleles are associated with vascular events and an aPL positive immune-phenotype in SLE. Results demonstrate that a subset of SLE patients is genetically disposed to vascular vulnerability.

  11. Oscillation of Angiogenesis and Vascular Dropout in Progressive Human Vascular Disease. [Vascular Pattern as Useful Read-Out of Complex Molecular Signaling

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia

    2010-01-01

    When analyzed by VESsel GENeration Analysis (VESGEN) software, vascular patterns provide useful integrative read-outs of complex, interacting molecular signaling pathways. Using VESGEN, we recently discovered and published our innovative, surprising findings that angiogenesis oscillated with vascular dropout throughout progression of diabetic retinopathy, a blinding vascular disease. Our findings provide a potential paradigm shift in the current prevailing view on progression and treatment of this disease, and a new early-stage window of regenerative therapeutic opportunities. The findings also suggest that angiogenesis may oscillate with vascular disease in a homeostatic-like manner during early stages of other inflammatory progressive diseases such as cancer and coronary vascular disease.

  12. VEGF signaling inside vascular endothelial cells and beyond.

    PubMed

    Eichmann, Anne; Simons, Michael

    2012-04-01

    Vascular endothelial growth factor-A (VEGF-A) has long been recognized as the key regulator of vascular development and function in health and disease. VEGF is a secreted polypeptide that binds to transmembrane tyrosine kinase VEGF receptors on the plasma membrane, inducing their dimerization, activation and assembly of a membrane-proximal signaling complex. Recent studies have revealed that many key events of VEGFR signaling occur inside the endothelial cell and are regulated by endosomal receptor trafficking. Plasma membrane VEGFR interacting molecules, including vascular guidance receptors Neuropilins and Ephrins also regulate VEGFR endocytosis and trafficking. VEGF signaling is increasingly recognized for its roles outside of the vascular system, notably during neural development, and blood vessels regulate epithelial branching morphogenesis. We review here recent advances in our understanding of VEGF signaling and its biological roles. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. [Vascular Calcification - Pathological Mechanism and Clinical Application - . Role of vascular smooth muscle cells in vascular calcification].

    PubMed

    Kurabayashi, Masahiko

    2015-05-01

    Vascular calcification is commonly seen with aging, chronic kidney disese (CKD), diabetes, and atherosclerosis, and is closely associated with cardiovascular morbidity and mortality. Vascular calcification has long been regarded as the final stage of degeneration and necrosis of arterial wall and a passive, unregulated process. However, it is now known to be an active and tightly regulated process involved with phenotypic transition of vascular smooth muscle cells (VSMC) that resembles bone mineralization. Briefly, calcium deposits of atherosclerotic plaque consist of hydroxyapatite and may appear identical to fully formed lamellar bone. By using a genetic fate mapping strategy, VSMC of the vascular media give rise to the majority of the osteochondrogenic precursor- and chondrocyte-like cells observed in the calcified arterial media of MGP (- / -) mice. Osteogenic differentiation of VSMC is characterized by the expression of bone-related molecules including bone morphogenetic protein (BMP) -2, Msx2 and osteopontin, which are produced by osteoblasts and chondrocytes. Our recent findings are that (i) Runx2 and Notch1 induce osteogenic differentiation, and (ii) advanced glycation end-product (AGE) /receptor for AGE (RAGE) and palmitic acid promote osteogenic differentiation of VSMC. To understand of the molecular mechanisms of vascular calcification is now under intensive research area.

  14. Uterine Vascular Lesions

    PubMed Central

    Vijayakumar, Abhishek; Srinivas, Amruthashree; Chandrashekar, Babitha Moogali; Vijayakumar, Avinash

    2013-01-01

    Vascular lesions of the uterus are rare; most reported in the literature are arteriovenous malformations (AVMs). Uterine AVMs can be congenital or acquired. In recent years, there has been an increasing number of reports of acquired vascular lesions of the uterus following pregnancy, abortion, cesarean delivery, and curettage. It can be seen from these reports that there is confusion concerning the terminology of uterine vascular lesions. There is also a lack of diagnostic criteria and management guidelines, which has led to an increased number of unnecessary invasive procedures (eg, angiography, uterine artery embolization, hysterectomy for abnormal vaginal bleeding). This article familiarizes readers with various vascular lesions of the uterus and their management. PMID:24340126

  15. Correlations of serum cystatin C and hs-CRP with vascular endothelial cell injury in patients with active systemic lupus erythematosus.

    PubMed

    Gao, Dong; Shao, Juan; Jin, Waishu; Xia, Xiujuan; Qu, Yan

    2018-05-22

    To investigate the correlations of serum cystatin C and high-sensitivity C-reactive protein (hs-CRP) with vascular endothelial cell injury in patients with active systemic lupus erythematosus (SLE). A total of 80 patients with SLE treated in our hospital from January 2016 to September 2017 were selected and randomly divided into stable-stage group (n=40) and active-stage group (n=40) using a random number table. The expressions of cystatin C and hs-CRPin stable and active stages were compared, and the inner diameters of brachial artery and levels of vascular endothelial growth factors in stable and active stages were also compared.The correlationsof expressions of cystatin C and hs-CRP in active stage with the inner diameter of brachial artery and vascular endothelial growth factor were analyzed. At the same time, the correlation between vascular endothelial growth factor and inner diameter of brachial artery in active stage was analyzed. The level of cystatin C in active stage was higher than that in stable stage (P<0.05), and the expression level of hs-CRP in active stage was also higher than that in stable stage (P<0.05). The inner diameter of brachial artery in active stage was smaller than that in stable stage (P<0.05), butthe level of vascular endothelial growth factor was higher than that in stable stage (P<0.05). The expressions of cystatin C and hs-CRP were negatively correlated with the inner diameter of brachial artery in active stage (P<0.05). The expressions of cystatin C and hs-CRP were positively correlated with vascular endothelial growth factor in active stage (P<0.05). Moreover, there was a negative correlation between vascular endothelial growth factor and inner diameter of brachial artery in active stage (P<0.05). Levels of cystatin C and hs-CRP are significantly increased in patients with active SLE, and the increase degrees are negatively correlated with the inner diameter of brachial artery under ultrasound, but positively correlated with the

  16. Regulatory mechanisms for specification and patterning of plant vascular tissues.

    PubMed

    Caño-Delgado, Ana; Lee, Ji-Young; Demura, Taku

    2010-01-01

    Plant vascular tissues, the conduits of water, nutrients, and small molecules, play important roles in plant growth and development. Vascular tissues have allowed plants to successfully adapt to various environmental conditions since they evolved 450 Mya. The majority of plant biomass, an important source of renewable energy, comes from the xylem of the vascular tissues. Efforts have been made to identify the underlying mechanisms of cell specification and patterning of plant vascular tissues and their proliferation. The formation of the plant vascular system is a complex process that integrates signaling and gene regulation at transcriptional and posttranscriptional levels. Recently, a wealth of molecular genetic studies and the advent of cell biology and genomic tools have enabled important progress toward understanding its underlying mechanisms. Here, we provide a comprehensive review of the cell and developmental processes of plant vascular tissue and resources recently available for studying them that will enable the discovery of new ways to develop sustainable energy using plant biomass.

  17. Endothelial dysfunction in metabolic and vascular disorders.

    PubMed

    Polovina, Marija M; Potpara, Tatjana S

    2014-03-01

    Vascular endothelium has important regulatory functions in the cardiovascular system and a pivotal role in the maintenance of vascular health and metabolic homeostasis. It has long been recognized that endothelial dysfunction participates in the pathogenesis of atherosclerosis from early, preclinical lesions to advanced, thrombotic complications. In addition, endothelial dysfunction has been recently implicated in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Considering that states of insulin resistance (eg, metabolic syndrome, impaired fasting glucose, impaired glucose tolerance, and T2DM) represent the most prevalent metabolic disorders and risk factors for atherosclerosis, it is of considerable scientific and clinical interest that both metabolic and vascular disorders have endothelial dysfunction as a common background. Importantly, endothelial dysfunction has been associated with adverse outcomes in patients with established cardiovascular disease, and a growing body of evidence indicates that endothelial dysfunction also imparts adverse prognosis in states of insulin resistance. In this review, we discuss the association of insulin resistance and T2DM with endothelial dysfunction and vascular disease, with a focus on the underlying mechanisms and prognostic implications of the endothelial dysfunction in metabolic and vascular disorders. We also address current therapeutic strategies for the improvement of endothelial dysfunction.

  18. Estrogen, vascular estrogen receptor and hormone therapy in postmenopausal vascular disease.

    PubMed

    Khalil, Raouf A

    2013-12-15

    Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women's Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject's age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Estrogen, Vascular Estrogen Receptor and Hormone Therapy in Postmenopausal Vascular Disease

    PubMed Central

    Khalil, Raouf A.

    2013-01-01

    Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women’s Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject’s age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. PMID:24099797

  20. A semi-automated vascular access system for preclinical models

    NASA Astrophysics Data System (ADS)

    Berry-Pusey, B. N.; Chang, Y. C.; Prince, S. W.; Chu, K.; David, J.; Taschereau, R.; Silverman, R. W.; Williams, D.; Ladno, W.; Stout, D.; Tsao, T. C.; Chatziioannou, A.

    2013-08-01

    Murine models are used extensively in biological and translational research. For many of these studies it is necessary to access the vasculature for the injection of biologically active agents. Among the possible methods for accessing the mouse vasculature, tail vein injections are a routine but critical step for many experimental protocols. To perform successful tail vein injections, a high skill set and experience is required, leaving most scientists ill-suited to perform this task. This can lead to a high variability between injections, which can impact experimental results. To allow more scientists to perform tail vein injections and to decrease the variability between injections, a vascular access system (VAS) that semi-automatically inserts a needle into the tail vein of a mouse was developed. The VAS uses near infrared light, image processing techniques, computer controlled motors, and a pressure feedback system to insert the needle and to validate its proper placement within the vein. The VAS was tested by injecting a commonly used radiolabeled probe (FDG) into the tail veins of five mice. These mice were then imaged using micro-positron emission tomography to measure the percentage of the injected probe remaining in the tail. These studies showed that, on average, the VAS leaves 3.4% of the injected probe in the tail. With these preliminary results, the VAS system demonstrates the potential for improving the accuracy of tail vein injections in mice.

  1. Angiogenesis and Vascular Architecture in Pheochromocytomas

    PubMed Central

    Favier, Judith; Plouin, Pierre-François; Corvol, Pierre; Gasc, Jean-Marie

    2002-01-01

    Angiogenesis is a critical step in tumor growth and metastatic invasion. We here report the study of the vascular status of 10 benign and 9 malignant pheochromocytomas. We examined the vascular architecture after immunostaining endothelial cells (CD34) and vascular smooth muscle cells (α-actin) and identified a vascular pattern characteristic of malignant lesions. To define a gene expression profile indicative of the invasive phenotype, we studied by in situ hybridization the expression of genes encoding several pro- and anti-angiogenic factors [hypoxia-inducible factor (HIF-1α), EPAS1, vascular endothelial growth factor (VEGF), VEGF receptors, angiopoietins and their receptor Tie2, five genes of the endothelin system, and thrombospondin 1]. A semiquantitative evaluation of the labeling revealed an induction of genes encoding EPAS1, VEGF, VEGFR-1, VEGFR-2, endothelin receptor, type B (ETB) and endothelin receptor, type A (ETA) in malignant pheochromocytomas as compared to benign tumors. These differences were observed in tumor cells, in endothelial cells, or in both. Quantification by real-time reverse-transcriptase polymerase chain reaction showed an increase of EPAS1, VEGF, and ETB transcripts of 4.5-, 3.5-, and 10-fold, respectively, in malignant versus benign tumors. Furthermore, we observed a strong correlation between the expression of EPAS1 and VEGF in tumoral tissue and between EPAS1 and ETB in endothelial cells. Altogether, our observations show that analysis of angiogenesis provides promising new criteria for the diagnosis of malignant pheochromocytomas. PMID:12368197

  2. Neuronal clues to vascular guidance.

    PubMed

    Suchting, Steven; Bicknell, Roy; Eichmann, Anne

    2006-03-10

    The development of the vertebrate vascular system into a highly ordered and stereotyped network requires precise control over the branching and growth of new vessels. Recent research has highlighted the important role of genetic programs in regulating vascular patterning and in particular has established a crucial role for families of molecules previously described in controlling neuronal guidance. Like neurons, new vessels are guided along the correct path by integrating attractive and repulsive cues from the external environment. This is achieved by specialised endothelial cells at the leading tip of vessel sprouts which express receptor proteins that couple extracellular guidance signals with the cytoskeletal changes necessary to alter cell direction. Here, we review the genetic and in vitro evidence implicating four families of ligand-receptor signalling systems common to both neuronal and vessel guidance: the Ephrins and Eph receptors; Semaphorins, Neuropilins and Plexin receptors; Netrin and Unc5 receptors; and Slits and Robo receptors.

  3. Immediate and long-term consequences of vascular toxicity during zebrafish development

    EPA Science Inventory

    Proper formation of the vascular system is necessary for embryogenesis, and chemical disruption of vascular development may be a key event driving developmental toxicity. In order to test the effect of environmental chemicals on this critical process, we developed a quantitative ...

  4. Brain Arterial Diameters as a Risk Factor for Vascular Events.

    PubMed

    Gutierrez, Jose; Cheung, Ken; Bagci, Ahmet; Rundek, Tatjana; Alperin, Noam; Sacco, Ralph L; Wright, Clinton B; Elkind, Mitchell S V

    2015-08-06

    Arterial luminal diameters are routinely used to assess for vascular disease. Although small diameters are typically considered pathological, arterial dilatation has also been associated with disease. We hypothesize that extreme arterial diameters are biomarkers of the risk of vascular events. Participants in the Northern Manhattan Study who had a time-of-flight magnetic resonance angiography were included in this analysis (N=1034). A global arterial Z-score, called the brain arterial remodeling (BAR) score, was obtained by averaging the measured diameters within each individual. Individuals with a BAR score <-2 SDs were considered to have the smallest diameters, individuals with a BAR score >-2 and <2 SDs had average diameters, and individuals with a BAR score >2 SDs had the largest diameters. All vascular events were recorded prospectively after the brain magnetic resonance imaging. Spline curves and incidence rates were used to test our hypothesis. The association of the BAR score with death (P=0.001), vascular death (P=0.02), any vascular event (P=0.05), and myocardial infarction (P=0.10) was U-shaped except for ischemic stroke (P=0.74). Consequently, incidence rates for death, vascular death, myocardial infarction, and any vascular event were higher in individuals with the largest diameters, whereas individuals with the smallest diameters had a higher incidence of death, vascular death, any vascular event, and ischemic stroke compared with individuals with average diameters. The risk of death, vascular death, and any vascular event increased at both extremes of brain arterial diameters. The pathophysiology linking brain arterial remodeling to systemic vascular events needs further research. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  5. Implementation of a virtual vascular clinic with point-of-care ultrasound in an integrated health care system.

    PubMed

    Lin, Judith C; Crutchfield, Janelle M; Zurawski, Dana K; Stevens, Courtney

    2018-02-01

    Using secured videoconferencing technologies, telemedicine may replace traditional clinic visits, save patients' time and travel, and improve use of limited surgeon and facility resources. We report our initial experience of the remote clinical encounter (RCE) by evaluating vascular surgery patients. In this proof-of-concept pilot study, we conducted telemedicine evaluations of vascular patients at a tertiary care institution from October 2015 to August 2016. Patients were offered synchronous virtual visits from a surgical provider in lieu of an in-person visit. We used Skype for Business (Microsoft, Redmond, Wash) over secured networks for patient-provider interaction, clinical data entry in the Epic electronic medical record (Epic Systems Corporation, Verona, Wisc) for documentation, and established satellite facilities with existing vascular laboratories for imaging and laboratory testing. We evaluated feasibility, demographics, encounter type, and satisfaction of the patient through web-based questionnaires. During a 10-month period, 41 women and 14 men with an average age of 57 years (range, 29-79 years) underwent 82 RCEs. There were 43 white (78.1%), 9 black (16.3%), 1 Asian (1.8%), and 2 Middle Eastern (3.6%) patients. Diagnoses included both arterial (aneurysm, carotid, and occlusive disease) and venous (deep venous thrombosis and varicose vein) disease. Among the 82 RCEs, visit types included 15 new patients, 30 postoperative visits, and 37 follow-up visits. Ultrasound imaging was performed in conjunction with the RCE in 74 patients (90.2%). Most patients (57%) had multiple RCEs during the study period. All 55 patients responded to the satisfaction questionnaire; 91% stated that they would highly recommend a virtual physician encounter to a friend or colleague, and all of the respondents found their encounter more convenient than having a traditional office visit. All patients thought that they were able to communicate clearly with the provider, and

  6. Adipose Stromal Vascular Fraction Isolation: A Head-to-Head Comparison of 4 Cell Separation Systems #2.

    PubMed

    Aronowitz, Joel A; Lockhart, Ryan A; Hakakian, Cloe S; Birnbaum, Zoe E

    2016-09-01

    With stromal vascular fraction (SVF) cell and adipose-derived stem cell-based technologies translating into the clinical setting, numerous isolation systems have been developed for the point of care isolation of SVF cells from adipose tissue. A relative lack of performance data on these systems can make objective assessment difficult for prospective clinicians. This study compared the performance of 4 SVF cell isolation systems. Four isolation systems were compared: the MultiStation by PNC International, the LipoKit by MediKhan, the GID SVF-2 platform by GID Europe Ltd, and the StemSource 900/MB system by Cytori Therapeutics, Inc. Identical lipoaspirate samples for 5 separate donors were used. Stromal vascular fraction output was compared in terms of nucleated cell yield, viability, residual collagenase activity, sterility of the output, colony-forming unit-fibroblast frequency, frequency of CD31-/CD34+/CD45- cells, and operating statistics. Mean process time ranged from 65.4 to 120.8 minutes. Mean nucleated cell yield per milliliter of tissue processed ranged from 1.01 × 10 cells/mL to 6.24 × 10 cells/mL. Mean cellular viability ranged from 50.3% to 84.02%. Residual collagenase activity was negligible across all systems. Observed colony-forming unit-fibroblast frequency ranged from 0.495% to 1.704%. No significant difference was observed in frequency of CD31-/CD34+/CD45- cells. Results of the anaerobic/aerobic cultures were mixed. There was considerable variability between the outputs of each system. The system used by a clinician should be tailored to the individual needs of the practice. There is a range of cost options available. This study may help clinicians make more educated decisions when choosing an isolation system to meet their clinical needs.

  7. Vascular and renal function in experimental thyroid disorders.

    PubMed

    Vargas, Félix; Moreno, Juan Manuel; Rodríguez-Gómez, Isabel; Wangensteen, Rosemary; Osuna, Antonio; Alvarez-Guerra, Miriam; García-Estañ, Joaquín

    2006-02-01

    This review focuses on the effects of thyroid hormones in vascular and renal systems. Special emphasis is given to the mechanisms by which thyroid hormones affect the regulation of body fluids, vascular resistance and, ultimately, blood pressure. Vascular function is markedly affected by thyroid hormones that produce changes in vascular reactivity and endothelial function in hyper- and hypothyroidism. The hypothyroid state is accompanied by a marked decrease in sensitivity to vasoconstrictors, especially to sympathetic agonists, alteration that may play a role in the reduced blood pressure of hypothyroid rats, as well as in the preventive effects of hypothyroidism on experimental hypertension. Moreover, in hypothyroid rats, the endothelium-dependent and nitric oxide donors vasodilation is reduced. Conversely, the vessels from hyperthyroid rats showed an increased endothelium-dependent responsiveness that may be secondary to the shear-stress induced by the hyperdynamic circulation, and that may contribute to the reduced vascular resistance characteristic of this disease. Thyroid hormones also have important effects in the kidney, affecting renal growth, renal haemodynamics, and salt and water metabolism. In hyperthyroidism, there is a resetting of the pressure-natriuresis relationship related to hyperactivity of the renin-angiotensin system, which contributes to the arterial hypertension associated with this endocrine disease. Moreover, thyroid hormones affect the development and/or maintenance of various forms of arterial hypertension. This review also describes recent advances in our understanding of thyroid hormone action on nitric oxide and oxidative stress in the regulation of cardiovascular and renal function and in the long-term control of blood pressure.

  8. VEGFR tyrosine kinase inhibitor II (VRI) induced vascular insufficiency in zebrafish as a model for studying vascular toxicity and vascular preservation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Shang; Dang, Yuan Ye; Oi Lam Che, Ginny

    In ischemic disorders such as chronic wounds and myocardial ischemia, there is inadequate tissue perfusion due to vascular insufficiency. Besides, it has been observed that prolonged use of anti-angiogenic agents in cancer therapy produces cardiovascular toxicity caused by impaired vessel integrity and regeneration. In the present study, we used VEGFR tyrosine kinase inhibitor II (VRI) to chemically induce vascular insufficiency in zebrafish in vivo and human umbilical vein endothelial cells (HUVEC) in vitro to further study the mechanisms of vascular morphogenesis in these pathological conditions. We also explored the possibility of treating vascular insufficiency by enhancing vascular regeneration and repairmore » with pharmacological intervention. We observed that pretreatment of VRI induced blood vessel loss in developing zebrafish by inhibiting angiogenesis and increasing endothelial cell apoptosis, accompanied by down-regulation of kdr, kdrl and flt-1 genes expression. The VRI-induced blood vessel loss in zebrafish could be restored by post-treatment of calycosin, a cardiovascular protective isoflavone. Similarly, VRI induced cytotoxicity and apoptosis in HUVEC which could be rescued by calycosin post-treatment. Further investigation of the underlying mechanisms showed that the PI3K/AKT/Bad cell survival pathway was a main contributor of the vascular regenerative effect of calycosin. These findings indicated that the cardiovascular toxicity in anti-angiogenic therapy was mainly caused by insufficient endothelial cell survival, suggesting its essential role in vascular integrity, repair and regeneration. In addition, we showed that VRI-induced blood vessel loss in zebrafish represented a simple and effective in vivo model for studying vascular insufficiency and evaluating cancer drug vascular toxicities. - Highlights: • In vivo VRI model • Rescue effects of calycosin • Calycosin EC survival pathways.« less

  9. Collagen vascular disease

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/001223.htm Collagen vascular disease To use the sharing features on ... were previously said to have "connective tissue" or "collagen vascular" disease. We now have names for many ...

  10. The - - and Submm-Wave Spectrum of Allyl Isocyanide and Radioastronomical Observations in Orion KL and the Primos Line Survey

    NASA Astrophysics Data System (ADS)

    Haykal, I.; Motiyenko, R. A.; Margules, L.; Huet, T. R.; Ecija, P.; Cocinero, E. J.; Basterretxea, F.; Fernandez, J. A.; Castano, F.; Tercero, B.; Cernicharo, J.; Lesarri, A.; Guillemin, J. C.

    2013-06-01

    Last year we presented the first rotational analysis of the ground state of the two conformers of allyl isocyanide from 4 GHz to 905 GHz. The analysis of the rotational spectrum of the cis conformer of allyl isocyanide was extended. We resolved Coriolis interactions of a and b types between the excited vibrational states ν_1=1 and ν_2=1, calculated to be at 156 cm^{-1} (A^{'}) and 167 cm^{-1} (A^{''}) respectively (MP2/aug-cc-pvtz), from 150 GHz to 600 GHz. Strong perturbations were observed in the 150-310 GHz range for low values of the quantum number K_a starting from K_a = 0, 1. The anharmonicities appeared as well at higher frequencies for larger quantum numbers. The two modes were fitted together with the SPFIT/SPCAT suite of programs and a set of Coriolis parameters was accurately determined. The fit contains more than 3000 lines up to J = 99 and K_a = 12 for both modes. We did not detect these species neither in the IRAM 30-m line survey of Orion KL nor in the PRIMOS survey towards SgrB2. Nevertheless, we provided upper limits to their column density in Orion KL. This work was supported by the CNES and the Action sur Projets de l'INSU, PCMI. I. Haykal et al. manuscript in preparation H. Pickett J. Mol. Spec.{148}, 371-377, 1991.

  11. 3D digital subtraction angiography of intracranial aneurysms: comparison of flat panel detector with conventional image intensifier TV system using a vascular phantom.

    PubMed

    Kakeda, S; Korogi, Y; Ohnari, N; Hatakeyama, Y; Moriya, J; Oda, N; Nishino, K; Miyamoto, W

    2007-05-01

    Compared with the image intensifier (I.I.)-TV system, the flat panel detector (FPD) system of direct conversion type has several theoretic advantages, such as higher spatial resolution, wide dynamic range, and no image distortion. The purpose of this study was to compare the image quality of 3D digital subtraction angiography (DSA) in the FPD and conventional I.I.-TV systems using a vascular phantom. An anthropomorphic vascular phantom was designed to simulate the various intracranial aneurysms with aneurysmal bleb. The tubes of this vascular phantom were filled with 2 concentrations of contrast material (300 and 150 mg I/mL), and we obtained 3D DSA using the FPD and I.I.-TV systems. First, 2 blinded radiologists compared the volume-rendering images for 3D DSA on the FPD and I.I.-TV systems, looking for pseudostenosis artifacts. Then, 2 other radiologists independently evaluated both systems for the depiction of the simulated aneurysm and aneurysmal bleb using a 5-point scale. For the degree of the pseudostenosis artifacts at the M1 segment of the middle cerebral artery at 300 mg I/mL, 3D DSA with FPD system showed mild stenoses, whereas severe stenoses were observed at 3D DSA with I.I.-TV system. At both concentrations, the FPD system was significantly superior to I.I.-TV system regarding the depiction of aneurysm and aneurysmal bleb. Compared with the I.I.-TV system, the FPD system could create high-resolution 3D DSA combined with a reduction of the pseudostenosis artifacts.

  12. Effects of heavy ion radiation on the brain vascular system and embryonic development

    NASA Technical Reports Server (NTRS)

    Yang, T. C.; Tobias, C. A.

    1984-01-01

    The present investigation is concerned with the effects of heavy-ion radiation on the vascular system and the embryonic development, taking into account the results of experiments with neonatal rats and mouse embryos. It is found that heavy ions can be highly effective in producing brain hemorrhages and in causing body deformities. Attention is given to aspects of methodology, the induction of brain hemorrhages by X-rays and heavy ions, and the effect of iron particles on embryonic development. Reported results suggest that high linear energy transfer (LET) heavy ions can be very effective in producing developmental abnormalities.

  13. Spanish Clinical Guidelines on Vascular Access for Haemodialysis.

    PubMed

    Ibeas, José; Roca-Tey, Ramon; Vallespín, Joaquín; Moreno, Teresa; Moñux, Guillermo; Martí-Monrós, Anna; Del Pozo, José Luis; Gruss, Enrique; Ramírez de Arellano, Manel; Fontseré, Néstor; Arenas, María Dolores; Merino, José Luis; García-Revillo, José; Caro, Pilar; López-Espada, Cristina; Giménez-Gaibar, Antonio; Fernández-Lucas, Milagros; Valdés, Pablo; Fernández-Quesada, Fidel; de la Fuente, Natalia; Hernán, David; Arribas, Patricia; Sánchez de la Nieta, María Dolores; Martínez, María Teresa; Barba, Ángel

    2017-11-01

    Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare. Copyright © 2017 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  14. Regulation of thrombosis and vascular function by protein methionine oxidation

    PubMed Central

    Gu, Sean X.; Stevens, Jeff W.

    2015-01-01

    Redox biology is fundamental to both normal cellular homeostasis and pathological states associated with excessive oxidative stress. Reactive oxygen species function not only as signaling molecules but also as redox regulators of protein function. In the vascular system, redox reactions help regulate key physiologic responses such as cell adhesion, vasoconstriction, platelet aggregation, angiogenesis, inflammatory gene expression, and apoptosis. During pathologic states, altered redox balance can cause vascular cell dysfunction and affect the equilibrium between procoagulant and anticoagulant systems, contributing to thrombotic vascular disease. This review focuses on the emerging role of a specific reversible redox reaction, protein methionine oxidation, in vascular disease and thrombosis. A growing number of cardiovascular and hemostatic proteins are recognized to undergo reversible methionine oxidation, in which methionine residues are posttranslationally oxidized to methionine sulfoxide. Protein methionine oxidation can be reversed by the action of stereospecific enzymes known as methionine sulfoxide reductases. Calcium/calmodulin-dependent protein kinase II is a prototypical methionine redox sensor that responds to changes in the intracellular redox state via reversible oxidation of tandem methionine residues in its regulatory domain. Several other proteins with oxidation-sensitive methionine residues, including apolipoprotein A-I, thrombomodulin, and von Willebrand factor, may contribute to vascular disease and thrombosis. PMID:25900980

  15. Regulation of thrombosis and vascular function by protein methionine oxidation.

    PubMed

    Gu, Sean X; Stevens, Jeff W; Lentz, Steven R

    2015-06-18

    Redox biology is fundamental to both normal cellular homeostasis and pathological states associated with excessive oxidative stress. Reactive oxygen species function not only as signaling molecules but also as redox regulators of protein function. In the vascular system, redox reactions help regulate key physiologic responses such as cell adhesion, vasoconstriction, platelet aggregation, angiogenesis, inflammatory gene expression, and apoptosis. During pathologic states, altered redox balance can cause vascular cell dysfunction and affect the equilibrium between procoagulant and anticoagulant systems, contributing to thrombotic vascular disease. This review focuses on the emerging role of a specific reversible redox reaction, protein methionine oxidation, in vascular disease and thrombosis. A growing number of cardiovascular and hemostatic proteins are recognized to undergo reversible methionine oxidation, in which methionine residues are posttranslationally oxidized to methionine sulfoxide. Protein methionine oxidation can be reversed by the action of stereospecific enzymes known as methionine sulfoxide reductases. Calcium/calmodulin-dependent protein kinase II is a prototypical methionine redox sensor that responds to changes in the intracellular redox state via reversible oxidation of tandem methionine residues in its regulatory domain. Several other proteins with oxidation-sensitive methionine residues, including apolipoprotein A-I, thrombomodulin, and von Willebrand factor, may contribute to vascular disease and thrombosis. © 2015 by The American Society of Hematology.

  16. Vascularized Composite Allografts: Procurement, Allocation, and Implementation.

    PubMed

    Rahmel, Axel

    Vascularized composite allotransplantation is a continuously evolving area of modern transplant medicine. Recently, vascularized composite allografts (VCAs) have been formally classified as 'organs'. In this review, key aspects of VCA procurement are discussed, with a special focus on interaction with the procurement of classical solid organs. In addition, options for a matching and allocation system that ensures VCA donor organs are allocated to the best-suited recipients are looked at. Finally, the different steps needed to promote VCA transplantation in society in general and in the medical community in particular are highlighted.

  17. Increased systemic vascular resistance in neonates with pulmonary hypertension.

    PubMed

    Milstein, J M; Goetzman, B W; Riemenschneider, T A; Wennberg, R P

    1979-11-01

    The time necessary for aortic diastolic pressure to decrease to 50 percent of an initially selected value after dissipation of the dicrotic notch (T 1/2) was determined in newborn infants with and without pulmonary hypertension. The mean T 1/2 was 671 +/- 167 msec in seven infants with clinical evidence of pulmonary hypertension and documented right to left ductus arteriosus shunting; 849 +/- 243 msec in nine infants with clinical evidence of pulmonary hypertension but no documented right to left ductus arteriosus shunting; and 457 +/- 66 msec in eight infants with hyaline membrane disease and no clinical evidence of pulmonary hypertension or a patent ductus arteriosus. The mean T 1/2 values in the former two groups were significantly different from that in the group with no pulmonary hypertension (P less than 0.01). An evaluation of factors affecting T 1/2 leads to the conclusion that the patients with pulmonary hypertension had increased systemic vascular resistance as well. This finding has important diagnostic, etiologic and therapeutic implications.

  18. Melbourne vascular surgical association audit.

    PubMed

    Beiles, C Barry

    2003-01-01

    The formation of the Melbourne Vascular Surgical Association has led to the establishment of a vascular surgical audit programme that commenced in January 1999. This has allowed establishment of a benchmark for quality assurance in vascular surgery in Australia. A consultative process allowed widespread adoption of the audit across all public hospital vascular units in Melbourne and the two largest regional centres in Victoria. Data were collected at two points during admission: at operation and at discharge. Risk stratification, using logistic regression and risk-adjusted ratios for adverse events was assessed for comparison of outcomes between units for the first 3 years of data collection. There is regular contact with all participants for data feedback and quality control. The standard of vascular surgery across Victoria is consistent, and there has been excellent compliance by all academic vascular units. Private practice data are less complete, and only half of the vascular surgeons have participated. A statewide audit process is feasible and viable. Coordination by the Melbourne Vascular Surgical Association is crucial for its continued success.

  19. Molecular Pathways of Notch Signaling in Vascular Smooth Muscle Cells

    PubMed Central

    Boucher, Joshua; Gridley, Thomas; Liaw, Lucy

    2012-01-01

    Notch signaling in the cardiovascular system is important during embryonic development, vascular repair of injury, and vascular pathology in humans. The vascular smooth muscle cell (VSMC) expresses multiple Notch receptors throughout its life cycle, and responds to Notch ligands as a regulatory mechanism of differentiation, recruitment to growing vessels, and maturation. The goal of this review is to provide an overview of the current understanding of the molecular basis for Notch regulation of VSMC phenotype. Further, we will explore Notch interaction with other signaling pathways important in VSMC. PMID:22509166

  20. Role of ROS signaling in differential hypoxic Ca2+ and contractile responses in pulmonary and systemic vascular smooth muscle cells.

    PubMed

    Wang, Yong-Xiao; Zheng, Yun-Min

    2010-12-31

    Hypoxia causes a large increase in [Ca2+]i and attendant contraction in pulmonary artery smooth muscle cells (PASMCs), but not in systemic artery SMCs. The different responses meet the respective functional needs in these two distinct vascular myocytes; however, the underlying molecular mechanisms are not well known. We and other investigators have provided extensive evidence to reveal that voltage-dependent K+ (KV) channels, canonical transient receptor potential (TRPC) channels, ryanodine receptor Ca2+ release channels (RyRs), cyclic adenosine diphosphate-ribose, FK506 binding protein 12.6, protein kinase C, NADPH oxidase and reactive oxygen species (ROS) are the essential effectors and signaling intermediates in the hypoxic increase in [Ca2+]i in PASMCs and HPV, but they may not primarily underlie the diverse cellular responses in pulmonary and systemic vascular myocytes. Hypoxia significantly increases mitochondrial ROS generation in PASMCs, which can induce intracellular Ca2+ release by opening RyRs, and may also cause extracellular Ca2+ influx by inhibiting KV channels and activating TRPC channels, leading to a large increase in [Ca2+]i in PASMCs and HPV. In contrast, hypoxia has no or a minor effect on mitochondrial ROS generation in systemic SMCs, thereby causing no change or a negligible increase in [Ca2+]i and contraction. Further preliminary work indicates that Rieske iron-sulfur protein in the mitochondrial complex III may perhaps serve as a key initial molecular determinant for the hypoxic increase in [Ca2+]i in PASMCs and HPV, suggesting its potential important role in different cellular changes to respond to hypoxic stimulation in pulmonary and systemic artery myocytes. All these findings have greatly improved our understanding of the molecular processes for the differential hypoxic Ca2+ and contractile responses in vascular SMCs from distinct pulmonary and systemic circulation systems. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. An early validation of the Society for Vascular Surgery lower extremity threatened limb classification system.

    PubMed

    Cull, David L; Manos, Ginger; Hartley, Michael C; Taylor, Spence M; Langan, Eugene M; Eidt, John F; Johnson, Brent L

    2014-12-01

    The Society for Vascular Surgery (SVS) recently established the Lower Extremity Threatened Limb Classification System, a staging system using Wound characteristic, Ischemia, and foot Infection (WIfI) to stratify the risk for limb amputation at 1 year. Although intuitive in nature, this new system has not been validated. The purpose of the following study was to determine whether the WIfI system is predictive of limb amputation and wound healing. Between 2007 and 2010, we prospectively obtained data related to wound characteristics, extent of infection, and degree of postrevascularization ischemia in 139 patients with foot wounds who presented for lower extremity revascularization (158 revascularization procedures). After adapting those data to the WIfI classifications, we analyzed the influence of wound characteristics, extent of infection, and degree of ischemia on time to wound healing; empirical Kaplan-Meier survival curves were compared with theoretical outcomes predicted by WIfI expert consensus opinion. Of the 158 foot wounds, 125 (79%) healed. The median time to wound healing was 2.7 months (range, 1-18 months). Factors associated with wound healing included presence of diabetes mellitus (P = .013), wound location (P = .049), wound size (P = .007), wound depth (P = .004), and degree of ischemia (P < .001). The WIfI clinical stage was predictive of 1-year limb amputation (stage 1, 3%; stage 2, 10%; stage 3, 23%; stage 4, 40%) and wound nonhealing (stage 1, 8%; stage 2, 10%; stage 3, 23%; stage 4, 40%) and correlated with the theoretical outcome estimated by the SVS expert panel. The theoretical framework for risk stratification among patients with critical limb ischemia provided by the SVS expert panel appears valid. Further validation of the WIfI classification system with multicenter data is justified. Copyright © 2014 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  2. Harnessing Electrostatic Forces to Grow Bio-inspired Hierarchical Vascular Networks

    NASA Astrophysics Data System (ADS)

    Behler, Kristopher; Melrose, Zachary; Schott, Andrew; Wetzel, Eric

    2012-02-01

    Vascular networks provide a system for fluid distribution. Artificial vascular materials with enhanced properties are currently being developed that could ultimately be integrated into systems reliant upon fluid transport while retaining their structural properties. An uninterrupted and controllable supply of liquid is optimal for many applications such as continual self-healing materials, in-situ delivery of index matched fluids, thermal management and drug delivery systems could benefit from a bio-inspired vascular approach that combines complex network geometries with minimal processing parameters. Two such approaches to induce vascular networks are electrohydrodynamic viscous fingering (EHVF) and electrical treeing (ET). EHVF is a phenomenon that occurs when a low viscosity liquid is forced through a high viscosity fluid or matrix, resulting in branches due to capillary and viscous forces in the high viscosity material. By applying voltages of 0 -- 60 kV, finger diameter is reduced. ET is the result of partial discharges in a dielectric material. In the vicinity of a small diameter electrode, the local electric field is greater than the global dielectric strength, causing a localized, step-wise, breakdown to occur forming a highly branched interconnected structure. ET is a viable method to produce networks on a smaller, micron, scale than the products of the EHVF method.

  3. Double-filter identification of vascular-expressed genes using Arabidopsis plants with vascular hypertrophy and hypotrophy.

    PubMed

    Ckurshumova, Wenzislava; Scarpella, Enrico; Goldstein, Rochelle S; Berleth, Thomas

    2011-08-01

    Genes expressed in vascular tissues have been identified by several strategies, usually with a focus on mature vascular cells. In this study, we explored the possibility of using two opposite types of altered tissue compositions in combination with a double-filter selection to identify genes with a high probability of vascular expression in early organ primordia. Specifically, we generated full-transcriptome microarray profiles of plants with (a) genetically strongly reduced and (b) pharmacologically vastly increased vascular tissues and identified a reproducible cohort of 158 transcripts that fulfilled the dual requirement of being underrepresented in (a) and overrepresented in (b). In order to assess the predictive value of our identification scheme for vascular gene expression, we determined the expression patterns of genes in two unbiased subsamples. First, we assessed the expression patterns of all twenty annotated transcription factor genes from the cohort of 158 genes and found that seventeen of the twenty genes were preferentially expressed in leaf vascular cells. Remarkably, fifteen of these seventeen vascular genes were clearly expressed already very early in leaf vein development. Twelve genes with published leaf expression patterns served as a second subsample to monitor the representation of vascular genes in our cohort. Of those twelve genes, eleven were preferentially expressed in leaf vascular tissues. Based on these results we propose that our compendium of 158 genes represents a sample that is highly enriched for genes expressed in vascular tissues and that our approach is particularly suited to detect genes expressed in vascular cell lineages at early stages of their inception. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  4. Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sevostyanova, V. V., E-mail: sevostyanova.victoria@gmail.com; Khodyrevskaya, Y. I.; Glushkova, T. V.

    The development of tissue-engineered small-diameter vascular grafts is an urgent issue in cardiovascular surgery. In this study, we assessed how the incorporation of the vascular endothelial growth factor (VEGF) affects morphological and mechanical properties of polycaprolactone (PCL) vascular grafts along with its release kinetics. Vascular grafts were prepared using two-phase electrospinning. In pursuing our aims, we performed scanning electron microscopy, mechanical testing, and enzyme-linked immunosorbent assay. Our results demonstrated the preservation of a highly porous structure and improvement of PCL/VEGF scaffold mechanical properties as compared to PCL grafts. A prolonged VEGF release testifies the use of this construct as amore » scaffold for tissue-engineered vascular grafts.« less

  5. Regulation and function of endothelial glycocalyx layer in vascular diseases.

    PubMed

    Sieve, Irina; Münster-Kühnel, Anja K; Hilfiker-Kleiner, Denise

    2018-01-01

    In the vascular system, the endothelial surface layer (ESL) as the inner surface of blood vessels affects mechanotransduction, vascular permeability, rheology, thrombogenesis, and leukocyte adhesion. It creates barriers between endothelial cells and blood and neighbouring cells. The glycocalyx, composed of glycoconjugates and proteoglycans, is an integral component of the ESL and a key element in inter- and intracellular communication and tissue homeostasis. In pathophysiological conditions (atherosclerosis, infection, ischemia/reperfusion injury, diabetes, trauma and acute lung injury) glycocalyx-degrading factors, i.e. reactive oxygen and nitrogen species, matrix metalloproteinases, heparanase and sialidases, damage the ESL, thereby impairing endothelial functions. This leads to increased capillary permeability, leucocyte-endothelium interactions, thrombosis and vascular inflammation, the latter further driving glycocalyx destruction. The present review highlights current knowledge on the vasculoprotective role of the ESL, with specific emphasis on its remodelling in inflammatory vascular diseases and discusses its potential as a novel therapeutic target to treat vascular pathologies. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Biomarkers of vascular risk, systemic inflammation, and microvascular pathology and neuropsychiatric symptoms in Alzheimer's disease.

    PubMed

    Hall, James R; Wiechmann, April R; Johnson, Leigh A; Edwards, Melissa; Barber, Robert C; Winter, A Scott; Singh, Meharvan; O'Bryant, Sid E

    2013-01-01

    Numerous serum and plasma based biomarkers of systemic inflammation have been linked to both neuropsychiatric disorders and Alzheimer's disease (AD). The present study investigated the relationship of clinical biomarkers of cardiovascular risk (cholesterol, triglycerides, and homocysteine) and a panel of markers of systemic inflammation (CRP, TNF-α, IL1-ra, IL-7, IL-10, IL-15, IL-18) and microvascular pathology (ICAM-1, VCAM-1) to neuropsychiatric symptoms in a sample with mild AD. Biomarker data was analyzed on a sample of 194 diagnosed with mild to moderate probable AD. The sample was composed of 127 females and 67 males. The presence of neuropsychiatric symptoms was gathered from interview with caretakers/family members using the Neuropsychiatric Inventory. For the total sample, IL-15, VCAM (vascular adhesion molecule), and triglycerides were significantly and negatively related to number of neuropsychiatric symptoms, and total cholesterol and homocysteine were positively related and as a group accounted for 16.1% of the variance. When stratified by gender, different patterns of significant biomarkers were found with relationships more robust for males for both total symptoms and symptom clusters. A combination of biomarkers of systemic inflammation, microvascular pathology, and clinical biomarkers of cardiovascular risk can account for a significant portion of the variance in the occurrence of neuropsychiatric symptoms in AD supporting a vascular and inflammatory component of psychiatric disorders found in AD. Gender differences suggest distinct impact of specific risks with total cholesterol, a measure of cardiovascular risk, being the strongest marker for males and IL-15, a marker of inflammation, being the strongest for females.

  7. Engineering Pre-vascularized Scaffolds for Bone Regeneration.

    PubMed

    Barabaschi, Giada D G; Manoharan, Vijayan; Li, Qing; Bertassoni, Luiz E

    2015-01-01

    Survival of functional tissue constructs of clinically relevant size depends on the formation of an organized and uniformly distributed network of blood vessels and capillaries. The lack of such vasculature leads to spatio-temporal gradients in oxygen, nutrients and accumulation of waste products inside engineered tissue constructs resulting in negative biological events at the core of the scaffold. Unavailability of a well-defined vasculature also results in ineffective integration of scaffolds to the host vasculature upon implantation. Arguably, one of the greatest challenges in engineering clinically relevant bone substitutes, therefore, has been the development of vascularized bone scaffolds. Various approaches ranging from peptide and growth factor functionalized biomaterials to hyper-porous scaffolds have been proposed to address this problem with reasonable success. An emerging alternative to address this challenge has been the fabrication of pre-vascularized scaffolds by taking advantage of biomanufacturing techniques, such as soft- and photo-lithography or 3D bioprinting, and cell-based approaches, where functional capillaries are engineered in cell-laden scaffolds prior to implantation. These strategies seek to engineer pre-vascularized tissues in vitro, allowing for improved anastomosis with the host vasculature upon implantation, while also improving cell viability and tissue development in vitro. This book chapter provides an overview of recent methods to engineer pre-vascularized scaffolds for bone regeneration. We first review the development of functional blood capillaries in bony structures and discuss controlled delivery of growth factors, co-culture systems, and on-chip studies to engineer vascularized cell-laden biomaterials. Lastly, we review recent studies using microfabrication techniques and 3D printing to engineer pre-vascularized scaffolds for bone tissue engineering.

  8. Non-invasive optical modulation of local vascular permeability

    NASA Astrophysics Data System (ADS)

    Choi, Myunghwan; Choi, Chulhee

    2011-03-01

    For a systemically administered drug to act, it first needs to cross the vascular wall. This step represents a bottleneck for drug development, especially in the brain or retina, where tight junctions between endothelial cells form physiological barriers. Here, we demonstrate that femtosecond pulsed laser irradiation focused on the blood vessel wall induces transient permeabilization of plasma. Nonlinear absorption of the pulsed laser enabled the noninvasive modulation of vascular permeability with high spatial selectivity in three dimensions. By combining this method with systemic injection, we could locally deliver molecular probes in various tissues, such as brain cortex, meninges, ear, striated muscle, and bone. We suggest this method as a novel delivery tool for molecular probes or drugs.

  9. Effects of vascularization on cancer nanochemotherapy outcomes

    NASA Astrophysics Data System (ADS)

    Paiva, L. R.; Ferreira, S. C.; Martins, M. L.

    2016-08-01

    Cancer therapy requires anticancer agents capable of efficient and uniform systemic delivery. One promising route to their development is nanotechnology. Here, a previous model for cancer chemotherapy based on a nanosized drug carrier (Paiva et al., 2011) is extended by including tissue vasculature and a three-dimensional growth. We study through computer simulations the therapy against tumors demanding either large or small nutrient supplies growing under different levels of tissue vascularization. Our results indicate that highly vascularized tumors demand more aggressive therapies (larger injected doses administrated at short intervals) than poorly vascularized ones. Furthermore, nanoparticle endocytic rate by tumor cells, not its selectivity, is the major factor that determines the therapeutic success. Finally, our finds indicate that therapies combining cytotoxic agents with antiangiogenic drugs that reduce the abnormal tumor vasculature, instead of angiogenic drugs that normalize it, can lead to successful treatments using feasible endocytic rates and administration intervals.

  10. Vascular twin nevi.

    PubMed

    Agirgol, Senay; Ozturk, Hatice Nur; Ozkok Akbulut, Tugba; Gunduzoglu, Ceyda; Koc, Leyli Kadriye; Turkoglu, Zafer

    2017-04-27

    Vascular twin nevi (VTN) are characterized by the simultaneous dermatological manifestatiton of a telangiectatic naevus close to a nevus anemicus. Nevus anemicus (NA) is a vascular anomaly characterized by localized pale patches with normal melanine and melanocyte level. According to twin spotting phenomenon crossing-over in heterozygous somatic-cells during mitosis results in two different offspring homozygous cells. Consequent to this mechanism, two different vascular anomalies may occur at the same region. We present a patient with VTN and NA combination which we think serves as an example for a rare twin spotting phenomenon in the literature. © 2017 Wiley Periodicals, Inc.

  11. Vasculature on the clock: Circadian rhythm and vascular dysfunction.

    PubMed

    Crnko, Sandra; Cour, Martin; Van Laake, Linda W; Lecour, Sandrine

    2018-05-17

    The master mammalian circadian clock (i.e. central clock), located in the suprachiasmatic nucleus of the hypothalamus, orchestrates the synchronization of the daily behavioural and physiological rhythms to better adapt the organism to the external environment in an anticipatory manner. This central clock is entrained by a variety of signals, the best established being light and food. However, circadian cycles are not simply the consequences of these two cues but are generated by endogenous circadian clocks. Indeed, clock machinery is found in mainly all tissues and cell types, including cells of the vascular system such as endothelial cells, fibroblasts, smooth muscle cells and stem cells. This machinery physiologically contributes to modulate the daily vascular function, and its disturbance therefore plays a major role in the pathophysiology of vascular dysfunction. Therapies targeting the circadian rhythm may therefore be of benefit against vascular disease. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Vascular corrosion casting technique steps.

    PubMed

    Verli, Flaviana Dornela; Rossi-Schneider, Tissiana Raquel; Schneider, Felipe Luís; Yurgel, Liliane Soares; de Souza, Maria Antonieta Lopes

    2007-01-01

    The vascular corrosion casting technique produces a replica of vascular beds of normal or pathological tissues. Once associated with scanning electron microscopy (SEM), this technique provides details of the three-dimensional anatomic arrangement of the vascular replica, which is the main advantage of this method. The present study is intended to describe the steps of the vascular corrosion casting technique and the different ways to perform them. them.

  13. Targeted systemic gene therapy and molecular imaging of cancer contribution of the vascular-targeted AAVP vector.

    PubMed

    Hajitou, Amin

    2010-01-01

    Gene therapy and molecular-genetic imaging have faced a major problem: the lack of an efficient systemic gene delivery vector. Unquestionably, eukaryotic viruses have been the vectors of choice for gene delivery to mammalian cells; however, they have had limited success in systemic gene therapy. This is mainly due to undesired uptake by the liver and reticuloendothelial system, broad tropism for mammalian cells causing toxicity, and their immunogenicity. On the other hand, prokaryotic viruses such as bacteriophage (phage) have no tropism for mammalian cells, but can be engineered to deliver genes to these cells. However, phage-based vectors have inherently been considered poor vectors for mammalian cells. We have reported a new generation of vascular-targeted systemic hybrid prokaryotic-eukaryotic vectors as chimeras between an adeno-associated virus (AAV) and targeted bacteriophage (termed AAV/phage; AAVP). In this hybrid vector, the targeted bacteriophage serves as a shuttle to deliver the AAV transgene cassette inserted in an intergenomic region of the phage DNA genome. As a proof of concept, we assessed the in vivo efficacy of vector in animal models of cancer by displaying on the phage capsid the cyclic Arg-Gly-Asp (RGD-4C) ligand that binds to alphav integrin receptors specifically expressed on the angiogenic blood vessels of tumors. The ligand-directed vector was able to specifically deliver imaging and therapeutic transgenes to tumors in mice, rats, and dogs while sparing the normal organs. This chapter reviews some gene transfer strategies and the potential of the vascular-targeted AAVP vector for enhancing the effectiveness of existing systemic gene delivery and genetic-imaging technologies. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  14. Cutaneous vascular anomalies associated with neural tube defects: nomenclature and pathology revisited.

    PubMed

    Maugans, Todd; Sheridan, Rachel M; Adams, Denise; Gupta, Anita

    2011-07-01

    Lumbosacral cutaneous vascular anomalies associated with neural tube defects are frequently described in the literature as "hemangiomas." The classification system for pediatric vascular anomalies developed by the International Society for the Study of Vascular Anomalies provides a framework to accurately diagnose these lesions. To apply this classification to vascular cutaneous anomalies overlying myelodysplasias. A retrospective analysis of patients with neural tube defects and lumbosacral cutaneous vascular lesions was performed. All eligible patients had detailed histopathologic analysis of skin and spinal cord/placode lesions. Clinical and radiologic features were analyzed. Conventional histology and GLUT-1 immunostaining were performed to differentiate infantile capillary hemangiomas from capillary vascular malformations. Ten cases with cutaneous lesions associated with neural tube defects were reviewed. Five lesions were diagnosed as infantile capillary hemangiomas based upon histology and positive GLUT-1 endothelial reactivity. These lesions had a strong association with dermal sinus tracts. No reoperations were required for residual intraspinal vascular lesions, and overlying cutaneous vascular anomalies involuted with time. The remaining 5 lesions were diagnosed as capillary malformations. These occurred with both open and closed neural tube defects, did not involute, and demonstrated enlargement and darkening due to vascular congestion. The International Society for the Study of Vascular Anomalies scheme should be used to describe the cutaneous vascular lesions associated with neural tube defects: infantile capillary hemangiomas and capillary malformations. We advocate that these lesions be described as "vascular anomalies" or "stains" pending accurate diagnosis by clinical, histological, and immunohistochemical evaluations.

  15. Vascular tissue engineering: towards the next generation vascular grafts.

    PubMed

    Naito, Yuji; Shinoka, Toshiharu; Duncan, Daniel; Hibino, Narutoshi; Solomon, Daniel; Cleary, Muriel; Rathore, Animesh; Fein, Corey; Church, Spencer; Breuer, Christopher

    2011-04-30

    The application of tissue engineering technology to cardiovascular surgery holds great promise for improving outcomes in patients with cardiovascular diseases. Currently used synthetic vascular grafts have several limitations including thrombogenicity, increased risk of infection, and lack of growth potential. We have completed the first clinical trial evaluating the feasibility of using tissue engineered vascular grafts (TEVG) created by seeding autologous bone marrow-derived mononuclear cells (BM-MNC) onto biodegradable tubular scaffolds. Despite an excellent safety profile, data from the clinical trial suggest that the primary graft related complication of the TEVG is stenosis, affecting approximately 16% of grafts within the first seven years after implantation. Continued investigation into the cellular and molecular mechanisms underlying vascular neotissue formation will improve our basic understanding and provide insights that will enable the rationale design of second generation TEVG. Published by Elsevier B.V.

  16. Characterization of midrib vascular bundles of selected medicinal species in Rubiaceae

    NASA Astrophysics Data System (ADS)

    Nurul-Syahirah, M.; Noraini, T.; Latiff, A.

    2016-11-01

    An anatomical study was carried out on mature leaves of five selected medicinal species of Rubiaceae from Peninsular Malaysia. The chosen medicinal species were Aidia densiflora, Aidia racemosa, Chasallia chartacea, Hedyotis auricularia and Ixora grandifolia. The objective of this study is to determine the taxonomic value of midrib anatomical characteristics. Leaves samples were collected from Taman Paku Pakis, Universiti Kebangsaan Malaysia, Bangi, Selangor and Kledang Saiong Forest Reserve, Perak, Malaysia. Leaves samples then were fixed in spirit and acetic acid (3:1), the midrib parts then were sectioned using sliding microtome, cleared using Clorox, stained in Safranin and Alcian blue, mounted in Euparal and were observed under light microscope. Findings in this study have shown all species have collateral bundles. The midrib vascular bundles characteristics that can be used as tool to differentiate between species or genus are vascular bundles system (opened or closed), shape and arrangement of main vascular bundles, presence of both additional and medullary vascular bundles, position of additional vascular bundles, shape of medullary vascular bundles, presence of sclerenchyma cells ensheathed the vascular bundles. As a conclusion, midrib anatomical characteristics can be used to identify and discriminate medicinal plants species studied in the Rubiaceae.

  17. Evaluation of a simplified augmented reality device for ultrasound-guided vascular access in a vascular phantom.

    PubMed

    Jeon, Yunseok; Choi, Seungpyo; Kim, Heechan

    2014-09-01

    To investigate whether a novel ultrasound device may be used with a simplified augmented reality technique, and to compare this device with conventional techniques during vascular access using a vascular phantom. Prospective, randomized study. Anesthesiology and Pain Medicine departments of a university-affiliated hospital. 20 physicians with no experience with ultrasound-guided techniques. All participants performed the vascular access technique on the vascular phantom model using both a conventional device and the new ultrasound device. Time and the number of redirections of the needle until aspiration of dye into a vessel of the vascular phantom were measured. The median/interquartile range of time was 39.5/41.7 seconds versus 18.6/10.0 seconds (P < 0.001) and number of redirections was 3/3.5 versus 1/0 (P < 0.001) for the conventional and novel ultrasound devices, respectively. During vascular access in a vascular phantom model, the novel device decreased the time and the number of redirections significantly. The device successfully improved the efficiency of the ultrasound-guided vascular access technique. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. The pathobiology of vascular dementia

    PubMed Central

    Iadecola, Costantino

    2013-01-01

    Vascular cognitive impairment defines alterations in cognition, ranging from subtle deficits to full-blown dementia, attributable to cerebrovascular causes. Often coexisting with Alzheimer’s disease, mixed vascular and neurodegenerative dementia has emerged as the leading cause of age-related cognitive impairment. Central to the disease mechanism is the crucial role that cerebral blood vessels play in brain health, not only for the delivery of oxygen and nutrients, but also for the trophic signaling that links inextricably the well being of neurons and glia to that of cerebrovascular cells. This review will examine how vascular damage disrupts these vital homeostatic interactions, focusing on the hemispheric white matter, a region at heightened risk for vascular damage, and on the interplay between vascular factors and Alzheimer’s disease. Finally, preventative and therapeutic prospects will be examined, highlighting the importance of midlife vascular risk factor control in the prevention of late-life dementia. PMID:24267647

  19. Loss of the Endothelial Glycocalyx Links Albuminuria and Vascular Dysfunction

    PubMed Central

    Ferguson, Joanne K.; Burford, James L.; Gevorgyan, Haykanush; Nakano, Daisuke; Harper, Steven J.; Bates, David O.; Peti-Peterdi, Janos

    2012-01-01

    Patients with albuminuria and CKD frequently have vascular dysfunction but the underlying mechanisms remain unclear. Because the endothelial surface layer, a meshwork of surface-bound and loosely adherent glycosaminoglycans and proteoglycans, modulates vascular function, its loss could contribute to both renal and systemic vascular dysfunction in proteinuric CKD. Using Munich-Wistar-Fromter (MWF) rats as a model of spontaneous albuminuric CKD, multiphoton fluorescence imaging and single-vessel physiology measurements revealed that old MWF rats exhibited widespread loss of the endothelial surface layer in parallel with defects in microvascular permeability to both water and albumin, in both continuous mesenteric microvessels and fenestrated glomerular microvessels. In contrast to young MWF rats, enzymatic disruption of the endothelial surface layer in old MWF rats resulted in neither additional loss of the layer nor additional changes in permeability. Intravenous injection of wheat germ agglutinin lectin and its adsorption onto the endothelial surface layer significantly improved glomerular albumin permeability. Taken together, these results suggest that widespread loss of the endothelial surface layer links albuminuric kidney disease with systemic vascular dysfunction, providing a potential therapeutic target for proteinuric kidney disease. PMID:22797190

  20. Predicting the need for vascular surgeons in Canada.

    PubMed

    Lotfi, Shamim; Jetty, Prasad; Petrcich, William; Hajjar, George; Hill, Andrew; Kubelik, Dalibor; Nagpal, Sudhir; Brandys, Tim

    2017-03-01

    With the introduction of direct entry (0+5) residency programs in addition to the traditional (5+2) programs, the number of vascular surgery graduates across Canada is expected to increase significantly during the next 5 to 10 years. Society's need for these newly qualified surgeons is unclear. This study evaluated the predicted requirement for vascular surgeons across Canada to 2021. A program director survey was also performed to evaluate program directors' perceptions of the 0+5 residency program, the expected number of new trainees, and faculty recruitment and retirement. The estimated and projected Canadian population numbers for each year between 2013 and 2021 were determined by the Canadian Socio-economic Information and Management System (CANSIM), Statistics Canada's key socioeconomic database. The number of vascular surgery procedures performed from 2008 to 2012 stratified by age, gender, and province was obtained from the Canadian Institute for Health Information Discharge Abstract Database. The future need for vascular surgeons was calculated by two validated methods: (1) population analysis and (2) workload analysis. In addition, a 12-question survey was sent to each vascular surgery program director in Canada. The estimated Canadian population in 2013 was 35.15 million, and there were 212 vascular surgeons performing a total of 98,339 procedures. The projected Canadian population by 2021 is expected to be 38.41 million, a 9.2% increase from 2013; however, the expected growth rate in the age group 60+ years, who are more likely to require vascular procedures, is expected to be 30% vs 3.4% in the age group <60 years. Using population analysis modeling, there will be a surplus of 10 vascular surgeons in Canada by 2021; however, using workload analysis modeling (which accounts for the more rapid growth and larger proportion of procedures performed in the 60+ age group), there will be a deficit of 11 vascular surgeons by 2021. Program directors in

  1. Adverse Outcome Pathways for Embryonic Vascular Disruption and Alternative Methods to Identify Chemical Vascular Disruptor

    EPA Science Inventory

    Chemically induced vascular toxicity during embryonic development can result in a wide range of adverse prenatal outcomes. We used information from genetic mouse models linked to phenotypic outcomes and a vascular toxicity knowledge base to construct an embryonic vascular disrupt...

  2. Vascular cognitive impairment and dementia.

    PubMed

    Gorelick, Philip B; Counts, Scott E; Nyenhuis, David

    2016-05-01

    Vascular contributions to cognitive impairment are receiving heightened attention as potentially modifiable factors for dementias of later life. These factors have now been linked not only to vascular cognitive disorders but also Alzheimer's disease. In this chapter we review 3 related topics that address vascular contributions to cognitive impairment: 1. vascular pathogenesis and mechanisms; 2. neuropsychological and neuroimaging phenotypic manifestations of cerebrovascular disease; and 3. prospects for prevention of cognitive impairment of later life based on cardiovascular and stroke risk modification. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Inducible nitric oxide synthase and vascular injury.

    PubMed

    Kibbe, M; Billiar, T; Tzeng, E

    1999-08-15

    The role nitric oxide (NO) plays in the cardiovascular system is complex and diverse. Even more controversial is the role that the inducible NO synthase enzyme (iNOS) serves in mediating different aspects of cardiovascular pathophysiology. Following arterial injury, NO has been shown to serve many vasoprotective roles, including inhibition of platelet aggregation and adherence to the site of injury, inhibition of leukocyte adherence, inhibition of vascular smooth muscle cell (VSMC) proliferation and migration, and stimulation of endothelial cell (EC) growth. These properties function together to preserve a normal vascular environment following injury. In this review, we discuss what is known about the involvement of iNOS in the vascular injury response. Additionally, we discuss the beneficial role of iNOS gene transfer to the vasculature in preventing the development of neointimal thickening. Lastly, the pathophysiology of transplant vasculopathy is discussed as well as the role of iNOS in this setting.

  4. Vascular Variations Associated with Intracranial Aneurysms.

    PubMed

    Orakdogen, Metin; Emon, Selin Tural; Somay, Hakan; Engin, Taner; Is, Merih; Hakan, Tayfun

    2017-01-01

    To investigate the vascular variations in patients with intracranial aneurysm in circle of Willis. We used the data on 128 consecutive intracranial aneurysm cases. Cerebral angiography images were analyzed retrospectively. Arteries were grouped as anterior cerebral arterial system (ACS), posterior cerebral arterial system (PCS) and middle cerebral arterial system (MCS) for grouping vascular variations. Lateralization, being single/multiple, gender; and also any connection with accompanying aneurysms" number, localization, dimension, whether bleeding/incidental aneurysm has been inspected. Variations were demonstrated in 57.8% of the cases. The most common variation was A1 variation (34.4%). The rate of variations was 36.7%, 24.2% and 10.2% respectively in ACS, PCS and MCS. MCS variations were significantly higher in males. Anterior communicating artery (ACoA) aneurysm observance rates were significantly higher and posterior communicating artery (PCoA) aneurysm and middle cerebral artery (MCA) aneurysm observance rates were significantly lower when compared to "no ACS variation detected" cases. In "PCS variation detected" cases, PCoA aneurysm observance rates and coexistence of multiple variations were significantly higher. The rate of vascular variations in patients with aneurysms was 57.8%. Arterial hypoplasia and aplasia were the most common variations. ACS was the most common region that variations were located in; they were mostly detected on the right side. Coexistence of ACoA aneurysm was higher than PCoA and MCA aneurysms. In the PCS variations group, PCoA aneurysms were the most common aneurysms that accompanying the variation and multiple variations were more common than in the other two groups. The variations in MCS were most common in males.

  5. Early life stage trimethyltin exposure induces ADP-ribosylation factor expression and perturbs the vascular system in zebrafish.

    PubMed

    Chen, Jiangfei; Huang, Changjiang; Truong, Lisa; La Du, Jane; Tilton, Susan C; Waters, Katrina M; Lin, Kuanfei; Tanguay, Robert L; Dong, Qiaoxiang

    2012-12-16

    Trimethyltin chloride (TMT) is an organotin contaminant, widely detected in aqueous environments, posing potential human and environmental risks. In this study, we utilized the zebrafish model to investigate the impact of transient TMT exposure on developmental progression, angiogenesis, and cardiovascular development. Embryos were waterborne exposed to a wide TMT concentration range from 8 to 96 h post fertilization (hpf). The TMT concentration that led to mortality in 50% of the embryos (LC(50)) at 96 hpf was 8.2 μM; malformations in 50% of the embryos (EC(50)) was 2.8 μM. The predominant response observed in surviving embryos was pericardial edema. Additionally, using the Tg (fli1a: EGFP) y1 transgenic zebrafish line to non-invasively monitor vascular development, TMT exposure led to distinct disarrangements in the vascular system. The most susceptible developmental stage to TMT exposure was between 48 and 72 hpf. High density whole genome microarrays were used to identify the early transcriptional changes following TMT exposure from 48 to 60 hpf or 72 hpf. In total, 459 transcripts were differentially expressed at least 2-fold (P<0.05) by TMT compared to control. Using Ingenuity Pathway Analysis (IPA) tools, it was revealed that the transcripts misregulated by TMT exposure were clustered in numerous categories including metabolic and cardiovascular disease, cellular function, cell death, molecular transport, and physiological development. In situ localization of highly elevated transcripts revealed intense staining of ADP-ribosylation factors arf3 and arf5 in the head, trunk, and tail regions. When arf5 expression was blocked by morpholinos, the zebrafish did not display the prototypical TMT-induced vascular deficits, indicating that the induction of arf5 was necessary for TMT-induced vascular toxicity. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. The Role of Pathogen-Secreted Proteins in Fungal Vascular Wilt Diseases

    PubMed Central

    de Sain, Mara; Rep, Martijn

    2015-01-01

    A limited number of fungi can cause wilting disease in plants through colonization of the vascular system, the most well-known being Verticillium dahliae and Fusarium oxysporum. Like all pathogenic microorganisms, vascular wilt fungi secrete proteins during host colonization. Whole-genome sequencing and proteomics screens have identified many of these proteins, including small, usually cysteine-rich proteins, necrosis-inducing proteins and enzymes. Gene deletion experiments have provided evidence that some of these proteins are required for pathogenicity, while the role of other secreted proteins remains enigmatic. On the other hand, the plant immune system can recognize some secreted proteins or their actions, resulting in disease resistance. We give an overview of proteins currently known to be secreted by vascular wilt fungi and discuss their role in pathogenicity and plant immunity. PMID:26473835

  7. Injuries to the vascular endothelium: vascular wall and endothelial dysfunction.

    PubMed

    Fisher, Mark

    2008-01-01

    Vascular endothelial injury has multiple elements, and this article focuses on ischemia-related processes that have particular relevance to ischemic stroke. Distinctions between necrotic and apoptotic cell death provide a basic science context in which to better understand the significance of classical core and penumbra concepts of acute stroke, with apoptotic processes particularly prominent in the penumbra. The mitochondria are understood to serve as a reservoir of proteins that mediate apoptosis. Oxidative stress pathways generating reactive oxygen species (ROS) are prominent in endothelial injury, both ischemic and nonischemic, with prominent roles of enzyme- and nonenzymemediated pathways; mitochondria once again have a critical role, particularly in the nonenzymatic pathways generating ROS. Inflammation also contributes to vascular endothelial injury, and endothelial cells have the capacity to rapidly increase expression of inflammatory mediators following ischemic challenge; this leads to enhanced leukocyte-endothelial interactions mediated by selectins and adhesion molecules. Preconditioning consists of a minor version of an injurious event, which in turn may protect vascular endothelium from injury following a more substantial event. Presence of the blood-brain barrier creates unique responses to endothelial injury, with permeability changes due to impairment of endothelial-matrix interactions compounding altered vasomotor tone and tissue perfusion mediated by nitric oxide. Pharmacological protection against vascular endothelial injury can be provided by several of the phosphodiesterases (cilostazol and dipyridamole), along with statins. Optimal clinical responses for protection of brain vascular endothelium may use preconditioning as a model, and will likely require combined protection against apoptosis, ROS, and inflammation.

  8. Microparticles (CD146) and Arterial Stiffness Versus Carotid Intima Media Thickness as an Early Predictors of Vascular Affection in Systemic Lupus Patients.

    PubMed

    Nassef, Sahar; El Guindey, Hala; Fawzy, Mary; Nasser, Amal; Reffai, Rasha; Shemiy, Doa

    2016-03-01

    This study aims to evaluate cluster of differentiation 146 (CD146) and pulse wave velocity (PWV) as non-invasive methods for prediction of early vascular affection in systemic lupus erythematosus (SLE) patients without symptoms of vascular disease, to detect the outcome and reproducibility of these methods, and to correlate CD146 and PWV with lipid profile, intima media thickness (IMT), and ankle brachial index. Thirty female SLE patients (mean age 26.6±6.6 years; range 15 to 35 years) fulfilling the American College of Rheumatology 1997 revised criteria for SLE classification, and 15 age and sex matched healthy controls were included. All participants were performed full clinical assessments including measurement of Systemic Lupus Erythematosus Disease Activity Index, lipid profile, CD146, carotid IMT, PWV, and rise time as an indication of how fast the waveform rises. Cluster of differentiation 146 levels were elevated in patients with SLE compared to controls (p<0.001). There was a statistically significant difference between patients and controls in the femoral, lower thigh, and ankle rise time. There was a statistically significant correlation between IMT and ages of patients, Systemic Lupus Erythematosus Disease Activity Index, and brachial-below knee PWV, while there was no correlation between IMT and disease duration, lipid profile, brachial-femoral PWV, and brachial-ankle PWV. There was statistically significant correlations between brachial-femoral PWV and serum cholesterol level, and between brachial-ankle PWV and low density lipoprotein cholesterol. Our results showed that SLE vascular affection is more pronounced in small arteries. Also, elevated CD146 and brachial-femoral PWV are useful early markers of vascular affection in SLE as well as rise time may be a marker for arterial stiffness.

  9. Vascular Dysfunction in Mother and Offspring During Preeclampsia: Contributions from Latin-American Countries.

    PubMed

    Giachini, Fernanda Regina; Galaviz-Hernandez, Carlos; Damiano, Alicia E; Viana, Marta; Cadavid, Angela; Asturizaga, Patricia; Teran, Enrique; Clapes, Sonia; Alcala, Martin; Bueno, Julio; Calderón-Domínguez, María; Ramos, María P; Lima, Victor Vitorino; Sosa-Macias, Martha; Martinez, Nora; Roberts, James M; Escudero, Carlos

    2017-10-06

    Pregnancy is a physiologically stressful condition that generates a series of functional adaptations by the cardiovascular system. The impact of pregnancy on this system persists from conception beyond birth. Recent evidence suggests that vascular changes associated with pregnancy complications, such as preeclampsia, affect the function of the maternal and offspring vascular systems, after delivery and into adult life. Since the vascular system contributes to systemic homeostasis, defective development or function of blood vessels predisposes both mother and infant to future risk for chronic disease. These alterations in later life range from fertility problems to alterations in the central nervous system or immune system, among others. It is important to note that rates of morbi-mortality due to pregnancy complications including preeclampsia, as well as cardiovascular diseases, have a higher incidence in Latin-American countries than in more developed countries. Nonetheless, there is a lack both in the amount and impact of research conducted in Latin America. An impact, although smaller, can be seen when research in vascular disorders related to problems during pregnancy is analyzed. Therefore, in this review, information about preeclampsia and endothelial dysfunction generated from research groups based in Latin-American countries will be highlighted. We relate the need, as present in many other countries in the world, for increased effective regional and international collaboration to generate new data specific to our region on this topic.

  10. Vascular tissue engineering: the next generation.

    PubMed

    Cleary, Muriel A; Geiger, Erik; Grady, Conor; Best, Cameron; Naito, Yuji; Breuer, Christopher

    2012-07-01

    It is the ultimate goal of tissue engineering: an autologous tissue engineered vascular graft (TEVG) that is immunologically compatible, nonthrombogenic, and can grow and remodel. Currently, native vessels are the preferred vascular conduit for procedures such as coronary artery bypass (CABG) or peripheral bypass surgery. However, in many cases these are damaged, have already been harvested, or are simply unusable. The use of synthetic conduits is severely limited in smaller diameter vessels due to increased incidence of thrombosis, infection, and graft failure. Current research has therefore energetically pursued the development of a TEVG that can incorporate into a patient's circulatory system, mimic the vasoreactivity and biomechanics of the native vasculature, and maintain long-term patency. Copyright © 2012. Published by Elsevier Ltd.

  11. Visfatin and cardio-cerebro-vascular disease.

    PubMed

    Wang, Pei; Vanhoutte, Paul M; Miao, Chao-Yu

    2012-01-01

    Nicotinamide phosphoribosyltransferase is the rate-limiting enzyme that catalyzes the first step in the biosynthesis of nicotinamide adenine dinucleotide from nicotinamide. This protein was originally cloned as a putative pre-B cell colony-enhancing factor and also found to be a visceral fat-derived adipokine (visfatin). As a multifunctional protein, visfatin plays an important role in immunity, metabolism, aging, inflammation, and responses to stress. Visfatin also participates in several pathophysiological processes contributing to cardio-cerebro-vascular diseases, including hypertension, atherosclerosis, ischemic heart disease, and ischemic stroke. However, whether visfatin is a friend or a foe in these diseases remains uncertain. This brief review focuses on the current understanding of the complex role of visfatin in the cardio-cerebro-vascular system under normal and pathophysiological conditions.

  12. Vascular repair strategies in type 2 diabetes: novel insights

    PubMed Central

    Kuschnerus, Kira; Landmesser, Ulf

    2015-01-01

    Impaired functions of vascular cells are responsible for the majority of complications in patients with type 2 diabetes (T2D). Recently a better understanding of mechanisms contributing to development of vascular dysfunction and the role of systemic inflammatory activation and functional alterations of several secretory organs, of which adipose tissue has more recently been investigated, has been achieved. Notably, the progression of vascular disease within the context of T2D appears to be driven by a multitude of incremental signaling shifts. Hence, successful therapies need to target several mechanisms in parallel, and over a long time period. This review will summarize the latest molecular strategies and translational developments of cardiovascular therapy in patients with T2D. PMID:26543824

  13. Impact of Disease Duration on Vascular Surrogates of Early Atherosclerosis in Childhood-Onset Systemic Lupus Erythematosus.

    PubMed

    Barsalou, Julie; Bradley, Timothy J; Tyrrell, Pascal N; Slorach, Cameron; Ng, Lawrence W K; Levy, Deborah M; Silverman, Earl D

    2016-01-01

    To determine whether longer disease duration negatively impacts carotid intima-media thickness (CIMT), flow-mediated dilation (FMD), and pulse wave velocity (PWV) in a cohort of patients with childhood-onset systemic lupus erythematosus (SLE), and to compare CIMT, FMD, and PWV in patients with childhood-onset SLE with those in healthy children and explore determinants of vascular test results in childhood-onset SLE. Cross-sectional analysis was performed in a prospective longitudinal cohort of patients with childhood-onset SLE at the latest followup visit. Clinical and laboratory data were collected for patients with childhood-onset SLE. CIMT, FMD, and PWV were measured using standardized protocols in patients with childhood-onset SLE and healthy children. Correlations between disease duration and results of the 3 vascular tests were performed. Vascular data in patients with childhood-onset SLE were compared with those in healthy children. Multivariable linear regression was used to identify determinants of CIMT, FMD, and PWV in childhood-onset SLE. Patients with childhood-onset SLE (n = 149) and healthy controls (n = 178) were enrolled. The median age of the patients was 17.2 years (interquartile range [IQR] 15.7-17.9 years), and their median disease duration was 3.2 years (IQR 1.8-4.9 years). The median age of the healthy children was 14.7 years (IQR 13.1-15.9 years). Longer disease duration correlated with worse FMD (r = -0.2, P = 0.031) in patients with childhood-onset SLE. Patients with childhood-onset SLE had smaller (better) CIMT, higher (better) FMD, and similar PWV compared with healthy controls. Linear regression analysis explained <24% of the variation in vascular test results in patients with childhood-onset SLE, suggesting that other variables should be explored as important determinants of CIMT, FMD, and PWV. In this cohort of 149 patients with childhood-onset SLE, patients did not have worse CIMT, FMD, or PWV than did healthy controls

  14. Does a birthday predispose to vascular events?

    PubMed

    Saposnik, Gustavo; Baibergenova, Akerke; Dang, Jason; Hachinski, Vladimir

    2006-07-25

    To examine the influence of birthdays on the onset and course of vascular events such as stroke, TIA, and acute myocardial infarction (AMI). This population-based study included all emergency department (ED) admissions due to ischemic stroke, TIA, or AMI from April 2002 to March 2004 in Ontario, Canada. All cases were identified through the National Ambulatory Care Reporting System. Calculations of daily and weekly numbers of events were centered on the patient's birthday and the week of the birthday. Statistical analyses include binomial tests and logistic regression. During the study period, there were 24,315 ED admissions with acute stroke, 16,088 with TIAs, and 29,090 with AMI. The observed number of vascular events during the birthday was higher than the expected daily number of visits for stroke (87 vs 67; p = 0.009), TIA (58 vs 44; p = 0.02), and AMI (97 vs 80; p = 0.027) but not for selected control conditions (asthma, appendicitis, head trauma). Vascular events were more likely to occur on birthday (242 vs 191; odds ratio [OR] = 1.27). No significant differences were observed during the birthday week for any of the conditions. Multivariate logistic regression showed that birthday vascular events were more likely to occur in patients with a history of hypertension (OR = 1.88; 95% CI 1.09 to 3.24). Sensitivity analyses with alternative definitions of birthday week did not alter the results. Stress associated with birthdays may trigger vascular events in patients with predisposing conditions.

  15. Relational databases for rare disease study: application to vascular anomalies.

    PubMed

    Perkins, Jonathan A; Coltrera, Marc D

    2008-01-01

    To design a relational database integrating clinical and basic science data needed for multidisciplinary treatment and research in the field of vascular anomalies. Based on data points agreed on by the American Society of Pediatric Otolaryngology (ASPO) Vascular Anomalies Task Force. The database design enables sharing of data subsets in a Health Insurance Portability and Accountability Act (HIPAA)-compliant manner for multisite collaborative trials. Vascular anomalies pose diagnostic and therapeutic challenges. Our understanding of these lesions and treatment improvement is limited by nonstandard terminology, severity assessment, and measures of treatment efficacy. The rarity of these lesions places a premium on coordinated studies among multiple participant sites. The relational database design is conceptually centered on subjects having 1 or more lesions. Each anomaly can be tracked individually along with their treatment outcomes. This design allows for differentiation between treatment responses and untreated lesions' natural course. The relational database design eliminates data entry redundancy and results in extremely flexible search and data export functionality. Vascular anomaly programs in the United States. A relational database correlating clinical findings and photographic, radiologic, histologic, and treatment data for vascular anomalies was created for stand-alone and multiuser networked systems. Proof of concept for independent site data gathering and HIPAA-compliant sharing of data subsets was demonstrated. The collaborative effort by the ASPO Vascular Anomalies Task Force to create the database helped define a common vascular anomaly data set. The resulting relational database software is a powerful tool to further the study of vascular anomalies and the development of evidence-based treatment innovation.

  16. Embryonic exposure to sodium arsenite perturbs vascular development in zebrafish.

    PubMed

    McCollum, Catherine W; Hans, Charu; Shah, Shishir; Merchant, Fatima A; Gustafsson, Jan-Åke; Bondesson, Maria

    2014-07-01

    Exposure to arsenic in its inorganic form, arsenite, causes adverse effects to many different organs and tissues. Here, we have investigated arsenite-induced adverse effects on vascular tissues in the model organism zebrafish, Danio rerio. Zebrafish embryos were exposed to arsenite at different exposure windows and the susceptibility to vascular tissue damage was recorded at 72hours post fertilization (hpf). Intersegmental vessel sprouting and growth was most perturbed by exposure to arsenite during the 24-48hpf window, while disruption in the condensation of the caudal vein plexus was more often observed at the 48-72hpf exposure window, reflecting when these structures develop during normal embryogenesis. The vascular growth rate was decreased by arsenite exposure, and deviated from that of control embryos at around 24-26.5hpf. We further mapped changes in expression of key regulators of angiogenesis and vasculogenesis. Downregulation of vascular endothelial growth factor receptor 1/fms-related tyrosine kinase 1 (vegfr1/flt1) expression was evident already at 24hpf, coinciding with the decreased vascular growth rate. At later time points, matrix metalloproteinase 9 (mmp9) expression was upregulated, suggesting that arsenite affects the composition of the extracellular matrix. In total, the expression of eight key factors involved in different aspects of vascularization was significantly altered by arsenic exposure. In conclusion, our results show that arsenite is a potent vascular disruptor in the developing zebrafish embryo, a finding that calls for an evaluation of arsenite as a developmental vascular toxicant in mammalian model systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Investigation of Tumor Cell Behaviors on a Vascular Microenvironment-Mimicking Microfluidic Chip

    PubMed Central

    Huang, Rong; Zheng, Wenfu; Liu, Wenwen; Zhang, Wei; Long, Yunze; Jiang, Xingyu

    2015-01-01

    The extravasation of tumor cells is a key event in tumor metastasis. However, the mechanism underlying tumor cell extravasation remains unknown, mainly hindered by obstacles from the lack of complexity of biological tissues in conventional cell culture, and the costliness and ethical issues of in vivo experiments. Thus, a cheap, time and labor saving, and most of all, vascular microenvironment-mimicking research model is desirable. Herein, we report a microfluidic chip-based tumor extravasation research model which is capable of simultaneously simulating both mechanical and biochemical microenvironments of human vascular systems and analyzing their synergistic effects on the tumor extravasation. Under different mechanical conditions of the vascular system, the tumor cells (HeLa cells) had the highest viability and adhesion activity in the microenvironment of the capillary. The integrity of endothelial cells (ECs) monolayer was destroyed by tumor necrosis factor-α (TNF-α) in a hemodynamic background, which facilitated the tumor cell adhesion, this situation was recovered by the administration of platinum nanoparticles (Pt-NPs). This model bridges the gap between cell culture and animal experiments and is a promising platform for studying tumor behaviors in the vascular system. PMID:26631692

  18. Detrimental effect of systemic vascular risk factors on brain hemodynamic function assessed with MRI.

    PubMed

    King, Kevin S; Sheng, Min; Liu, Peiying; Maroules, Christopher D; Rubin, Craig D; Peshock, Ron M; McColl, Roderick W; Lu, Hanzhang

    2018-06-01

    Background and purpose Vascular risk factors have been associated with decreased cerebral blood flow (CBF) but this is etiologically nonspecific and may result from vascular insufficiency or a response to decreased brain metabolic activity. We apply new MRI techniques to measure oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen consumption (CMRO 2 ), hypothesizing that decreased CBF related to these vascular risk factors will be associated with increased OEF, confirming a primary vascular insufficiency. Methods 3T MRI was obtained on 70 community-based participants in this IRB-approved study with informed consent, with previous assessment of systolic blood pressure, hypertension medication, elevated serum triglycerides, low serum HDL, and diabetes mellitus. CBF was measured using phase contrast adjusted for brain volume (ml/100 g/min), OEF (%) was obtained from T2-Relaxation-Under-Spin-Tagging (TRUST), and CMRO 2 (μmol/100 g/min) was derived using the Fick principle. Stepwise linear regression identified optimal predictors of CBF with age, sex, and hematocrit included for adjustment. This predictive model was then evaluated against OEF and CMRO 2 . Results Hypertriglyceridemia was associated with low CBF and high OEF. High systolic blood pressure was associated with high CBF and low OEF, which was primarily attributable to those with pressures above 160 mmHg. Neither risk factor was associated with significant differences in cerebral metabolic rate. Conclusion Low CBF related to hypertriglyceridemia was accompanied by high OEF with no significant difference in CMRO 2 , confirming subclinical vascular insufficiency. High CBF related to high systolic blood pressure likely reflected limitations of autoregulation at higher blood pressures.

  19. Vascular and Inflammatory Factors in the Pathophysiology of Blast-Induced Brain Injury

    PubMed Central

    Elder, Gregory A.; Gama Sosa, Miguel A.; De Gasperi, Rita; Stone, James Radford; Dickstein, Dara L.; Haghighi, Fatemeh; Hof, Patrick R.; Ahlers, Stephen T.

    2015-01-01

    Blast-related traumatic brain injury (TBI) has received much recent attention because of its frequency in the conflicts in Iraq and Afghanistan. This renewed interest has led to a rapid expansion of clinical and animal studies related to blast. In humans, high-level blast exposure is associated with a prominent hemorrhagic component. In animal models, blast exerts a variety of effects on the nervous system including vascular and inflammatory effects that can be seen with even low-level blast exposures which produce minimal or no neuronal pathology. Acutely, blast exposure in animals causes prominent vasospasm and decreased cerebral blood flow along with blood-brain barrier breakdown and increased vascular permeability. Besides direct effects on the central nervous system, evidence supports a role for a thoracically mediated effect of blast; whereby, pressure waves transmitted through the systemic circulation damage the brain. Chronically, a vascular pathology has been observed that is associated with alterations of the vascular extracellular matrix. Sustained microglial and astroglial reactions occur after blast exposure. Markers of a central and peripheral inflammatory response are found for sustained periods after blast injury and include elevation of inflammatory cytokines and other inflammatory mediators. At low levels of blast exposure, a microvascular pathology has been observed in the presence of an otherwise normal brain parenchyma, suggesting that the vasculature may be selectively vulnerable to blast injury. Chronic immune activation in brain following vascular injury may lead to neurobehavioral changes in the absence of direct neuronal pathology. Strategies aimed at preventing or reversing vascular damage or modulating the immune response may improve the chronic neuropsychiatric symptoms associated with blast-related TBI. PMID:25852632

  20. A vascular disease educational program in the preclinical years of medical school increases student interest in vascular disease.

    PubMed

    Godshall, Christopher J; Moore, Phillip S; Fleming, Shawn H; Andrews, Jeanette S; Hansen, Kimberley J; Hoyle, John R; Edwards, Matthew S

    2010-09-01

    New training paradigms in vascular surgery necessitate medical student interest in vascular disease. We examined the effects of incorporation of a vascular disease educational program during the second year of the medical school curriculum on student acquisition of knowledge and interest in the treatment of vascular disease. We developed and administered a new educational program on vascular disease and delivered the program to all second-year medical students. The new program encompassed 9 didactic hours, including 7 traditional lecture hours and 2 hours of problem-based learning. After completing the program, students were surveyed regarding vascular disease-specific knowledge, interest in treating vascular disease, and career choices. Third-year students who were not exposed to the program were surveyed as a control group. We recorded the voluntary student enrollment in the vascular and endovascular surgery rotation during the following academic year. Voluntary enrollment of the students exposed to the vascular disease education program was compared with enrollment for the previous 8 years. Before the introduction of the new educational program, 946 total lecture hours were delivered to first- and second-year medical students, comprising 490 hours (52%) given by nonsurgeon physicians, 445 (47%) by nonphysicians, and 11 (1%) by surgeons. Survey response rate was 93% (112 of 121) for second-year students and 95% (39 of 41) for third-year students. After the vascular disease program, second-year students answered 7.1 +/- 1.4 of 9 vascular disease questions correctly, whereas unexposed third-year students answered 7.2 +/- 1.7 questions correctly (P = .96). Most second-year medical students described a "somewhat" or "much greater" interest in the medical (63%), procedural (59%), and overall (63%) management of vascular disease after exposure to the program. Most also had a "somewhat" or "much greater" interest in a vascular medicine (64%) or vascular and endovascular

  1. Vascular Damage and Kidney Transplant Outcomes: An Unfriendly and Harmful Link.

    PubMed

    Hernández, Domingo; Triñanes, Javier; Armas, Ana María; Ruiz-Esteban, Pedro; Alonso-Titos, Juana; Duarte, Ana; González-Molina, Miguel; Palma, Eulalia; Salido, Eduardo; Torres, Armando

    2017-07-01

    Kidney transplant (KT) is the treatment of choice for most patients with chronic kidney disease, but this has a high cardiovascular mortality due to traditional and nontraditional risk factors, including vascular calcification. Inflammation could precede the appearance of artery wall lesions, leading to arteriosclerosis and clinical and subclinical atherosclerosis in these patients. Additionally, mineral metabolism disorders and activation of the renin-angiotensin system could contribute to this vascular damage. Thus, understanding the vascular lesions that occur in KT recipients and the pathogenic mechanisms involved in their development could be crucial to optimize the therapeutic management and outcomes in survival of this population. This review focuses on the following issues: (1) epidemiological data framing the problem; (2) atheromatosis in KT patients: subclinical and clinical atheromatosis, involving ischemic heart disease, congestive heart failure, stroke and peripheral vascular disease; (3) arteriosclerosis and vascular calcifications; and (4) potential pathogenic mechanisms and their therapeutic targets. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  2. Expression of Vascular Endothelial Growth Factor Receptors in Benign Vascular Lesions of the Orbit: A Case Series.

    PubMed

    Atchison, Elizabeth A; Garrity, James A; Castillo, Francisco; Engman, Steven J; Couch, Steven M; Salomão, Diva R

    2016-01-01

    Vascular lesions of the orbit, although not malignant, can cause morbidity because of their location near critical structures in the orbit. For the same reason, they can be challenging to remove surgically. Anti-vascular endothelial growth factor (VEGF) drugs are increasingly being used to treat diseases with prominent angiogenesis. Our study aimed to determine to what extent VEGF receptors and their subtypes are expressed on selected vascular lesions of the orbit. Retrospective case series of all orbital vascular lesions removed by one of the authors (JAG) at the Mayo Clinic. A total of 52 patients who underwent removal of vascular orbital lesions. The pathology specimens from the patients were retrieved, their pathologic diagnosis was confirmed, demographic and clinical information were gathered, and sections from vascular tumors were stained with vascular endothelial growth factor receptor (VEGFR), vascular endothelial growth factor receptor type 1 (VEGFR1), vascular endothelial growth factor receptor type 2 (VEGFR2), and vascular endothelial growth factor receptor type 3 (VEGFR3). The existence and pattern of staining with VEGF and its subtypes on these lesions. There were 28 specimens of venous malformations, 4 capillary hemangiomas, 7 lymphatic malformations, and 6 lymphaticovenous malformations. All samples stained with VEGF, 55% stained with VEGFR1, 98% stained with VEGFR2, and 96% stained with VEGFR3. Most (94%) of the VEGFR2 staining was diffuse. Most orbital vascular lesions express VEGF receptors, which may suggest a future target for nonsurgical treatment. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  3. Reimbursement in hospital-based vascular surgery: Physician and practice perspective.

    PubMed

    Perri, Jennifer L; Zwolak, Robert M; Goodney, Philip P; Rutherford, Gretchen A; Powell, Richard J

    2017-07-01

    The purpose of this study was to determine change in value of a vascular surgery division to the health care system during 6 years at a hospital-based academic practice and to compare physician vs hospital revenue earned during this period. Total revenue generated by the vascular surgery service line at an academic medical center from 2010 through 2015 was evaluated. Total revenue was measured as the sum of physician (professional) and hospital (technical) net revenue for all vascular-related patient care. Adjustments were made for work performed, case complexity, and inflation. To reflect the effect of these variables, net revenue was indexed to work relative value units (wRVUs), case mix index, and consumer price index, which adjusted for work, case complexity, and inflation, respectively. Differences in physician and hospital net revenue were compared over time. Physician work, measured in RVUs per year, increased by 4%; case complexity, assessed with case mix index, increased by 10% for the 6-year measurement period. Despite stability in payer mix at 64% to 69% Medicare, both physician and hospital vascular-related revenue/wRVU decreased during this period. Unadjusted professional revenue/wRVU declined by 14.1% (P = .09); when considering case complexity, physician revenue/wRVU declined by 20.6% (P = .09). Taking into account both case complexity and inflation, physician revenue declined by 27.0% (P = .04). Comparatively, hospital revenue for vascular surgery services decreased by 13.8% (P = .07) when adjusting for unit work, complexity, and inflation. At medical centers where vascular surgeons are hospital based, vascular care reimbursement decreased substantially from 2010 to 2015 when case complexity and inflation were considered. Physician reimbursement (professional fees) decreased at a significantly greater rate than hospital reimbursement for vascular care. This trend has significant implications for salaried vascular surgeons in hospital

  4. Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons.

    PubMed

    Fortuna, Vitor; Pardanaud, Luc; Brunet, Isabelle; Ola, Roxana; Ristori, Emma; Santoro, Massimo M; Nicoli, Stefania; Eichmann, Anne

    2015-06-23

    The sympathetic nervous system controls smooth muscle tone and heart rate in the cardiovascular system. Postganglionic sympathetic neurons (SNs) develop in close proximity to the dorsal aorta (DA) and innervate visceral smooth muscle targets. Here, we use the zebrafish embryo to ask whether the DA is required for SN development. We show that noradrenergic (NA) differentiation of SN precursors temporally coincides with vascular mural cell (VMC) recruitment to the DA and vascular maturation. Blocking vascular maturation inhibits VMC recruitment and blocks NA differentiation of SN precursors. Inhibition of platelet-derived growth factor receptor (PDGFR) signaling prevents VMC differentiation and also blocks NA differentiation of SN precursors. NA differentiation is normal in cloche mutants that are devoid of endothelial cells but have VMCs. Thus, PDGFR-mediated mural cell recruitment mediates neurovascular interactions between the aorta and sympathetic precursors and promotes their noradrenergic differentiation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Vascular Sap Proteomics: Providing Insight into Long-Distance Signaling during Stress

    PubMed Central

    Carella, Philip; Wilson, Daniel C.; Kempthorne, Christine J.; Cameron, Robin K.

    2016-01-01

    The plant vascular system, composed of the xylem and phloem, is important for the transport of water, mineral nutrients, and photosynthate throughout the plant body. The vasculature is also the primary means by which developmental and stress signals move from one organ to another. Due to practical and technological limitations, proteomics analysis of xylem and phloem sap has been understudied in comparison to accessible sample types such as leaves and roots. However, recent advances in sample collection techniques and mass spectrometry technology are making it possible to comprehensively analyze vascular sap proteomes. In this mini-review, we discuss the emerging field of vascular sap proteomics, with a focus on recent comparative studies to identify vascular proteins that may play roles in long-distance signaling and other processes during stress responses in plants. PMID:27242852

  6. Patterning vascular networks in vivo for tissue engineering applications.

    PubMed

    Chaturvedi, Ritika R; Stevens, Kelly R; Solorzano, Ricardo D; Schwartz, Robert E; Eyckmans, Jeroen; Baranski, Jan D; Stapleton, Sarah Chase; Bhatia, Sangeeta N; Chen, Christopher S

    2015-05-01

    The ultimate design of functionally therapeutic engineered tissues and organs will rely on our ability to engineer vasculature that can meet tissue-specific metabolic needs. We recently introduced an approach for patterning the formation of functional spatially organized vascular architectures within engineered tissues in vivo. Here, we now explore the design parameters of this approach and how they impact the vascularization of an engineered tissue construct after implantation. We used micropatterning techniques to organize endothelial cells (ECs) into geometrically defined "cords," which in turn acted as a template after implantation for the guided formation of patterned capillaries integrated with the host tissue. We demonstrated that the diameter of the cords before implantation impacts the location and density of the resultant capillary network. Inclusion of mural cells to the vascularization response appears primarily to impact the dynamics of vascularization. We established that clinically relevant endothelial sources such as induced pluripotent stem cell-derived ECs and human microvascular endothelial cells can drive vascularization within this system. Finally, we demonstrated the ability to control the juxtaposition of parenchyma with perfused vasculature by implanting cords containing a mixture of both a parenchymal cell type (hepatocytes) and ECs. These findings define important characteristics that will ultimately impact the design of vasculature structures that meet tissue-specific needs.

  7. Congenital portosystemic vascular malformations.

    PubMed

    Guérin, Florent; Blanc, Thomas; Gauthier, Frédéric; Abella, Stephanie Franchi; Branchereau, Sophie

    2012-08-01

    Congenital portosystemic shunts are developmental abnormalities of the portal venous system resulting in the diversion of portal blood away from the liver to the systemic venous system. Such malformations are believed to come from an insult occurring between the fourth and eighth week of gestation during the development of hepatic and systemic venous systems, and could explain their frequent association with cardiac and other vascular anomalies. They are currently categorized into end-to-side shunts (type I) or side-to-side shunts (type II). This article aims to review the common symptoms and complications encountered in congenital portosystemic shunts, the surgical and endovascular treatment, and the role of liver transplantation in this disease. We will also focus on the current controversies and the areas where there is potential for future studies. Copyright © 2012. Published by Elsevier Inc.

  8. [Orbito-palpebral vascular pathology].

    PubMed

    Heran Dreyfus, F; Galatoire, O; Koskas, P; Lafitte, F; Nau, E; Bergès, O

    2016-11-01

    Orbito-palpebral vascular pathology represents 10% of all the diseases of this area. The lesion may be discovered during a brain CT scan or MRI, or because it causes clinical symptoms such as orbital mass, visual or oculomotor alteration, pain, proptosis, or acute bleeding due to a complication of the lesion (hemorrhage, thrombosis). We present these lesions using an anatomical, clinical, imaging and therapeutic approach. We distinguish four different entities. Vascular tumors have common imaging characteristics (hypersignal on T2 sequence, contrast enhancement, abnormal vascularization well depicted with ultrasound and Doppler, and possible bleeding). The main lesions are cavernous hemangiomas, the most frequent lesion of that type during adulthood; infantile hemangiomas, the most frequent vascular tumor in children; and more seldomly, hemangioperitcytomas. True vascular malformations are divided according to their flow. Low flow lesions are venous (orbital varix), capillarovenous or lymphatic (lymphangioma). High flow malformations, more rare, are either arteriovenous or arterial malformations (aneurisms). Complex malformations include both low and high flow elements. Lesions leading to modifications of the orbito-palpebral blood flow are mainly due to cavernous sinus abnormalities, either direct carotid-cavernous fistula affecting young adults after severe head trauma, or dural fistula, more insidious, found in older adults. The last section is devoted to congenital syndromic vascular malformations (Sturge-Weber, Rendu-Olser…). This classification allows for a better understanding of these pathologies and their specific imaging features. Copyright © 2016. Published by Elsevier Masson SAS.

  9. [Cerebellar infarction in vascular teritorry of arteria cerebelli superior].

    PubMed

    Savić, Dejan; Savić, Ljiljana

    2010-01-01

    Cerebellar vascular diseases are focal cerebrovascular diseases in posterior circulation--vertebrobasilar system. The cerebellum is supplied by three main arteries arising from the vertebrobasilar system: arteria cerebelli inferior posterior, arteria cerebelli inferior anterior and arteria cerebelli superior. Cerebelar infarctions are rare but unpredictable disorders. The aim of this study was determination of main risk factors, clinical presentation and prognosis of the cerebellar infarctions in distal vascular teritorry of the arteria cerebelli superior. We evaluated 60 patients hospitalized after acute cerebellar infarction among other hospitalized patients in five year period. In 18 patients computerized tomography demonstrated infarction in distal vascular teritorry of the arteria cerebelli superior. All patients underwent clinical and other diagnostic investigations (computerized tomography, electrocardyography and standard blood tests) and were questioned by phone after finishing hospital treatment. Cerebellar infarcts in distal vascular teritorry of arteria cerebell superior was 30% of all cerebellar infarcts. The most frequent risk factor was hypertension (66.7%). Symptomatology and clinical signs were heterogenous but the most frequent were instability (77.8%), vertigo (72.2%) and vomiting (55.6%) followed by ataxia of the limbs (77.8%) and the body (61.1%), nystagmus (55.6%) and disarthria (33.3%) in clinical presentation. All patients had good recovery in hospital and one year afterwards. Infarctions in distribution of arteria cerebelli superior are rare and have multiple risk factors and various clinical features in majority of other studies as in this one. Mass effects are present in several studies but none in this one which reflects contraversions present in other published investigations. Cerebellar infarctions in vascular teritorry of arteria cerebelli superior have multiple risk factors, mostly heterogenous clinical presentations with

  10. Open and endovascular aneurysm repair in the Society for Vascular Surgery Vascular Quality Initiative.

    PubMed

    Spangler, Emily L; Beck, Adam W

    2017-12-01

    The Society for Vascular Surgery Vascular Quality Initiative is a patient safety organization and a collection of procedure-based registries that can be utilized for quality improvement initiatives and clinical outcomes research. The Vascular Quality Initiative consists of voluntary participation by centers to collect data prospectively on all consecutive cases within specific registries which physicians and centers elect to participate. The data capture extends from preoperative demographics and risk factors (including indications for operation), through the perioperative period, to outcomes data at up to 1-year of follow-up. Additionally, longer-term follow-up can be achieved by matching with Medicare claims data, providing long-term longitudinal follow-up for a majority of patients within the Vascular Quality Initiative registries. We present the unique characteristics of the Vascular Quality Initiative registries and highlight important insights gained specific to open and endovascular abdominal aortic aneurysm repair. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System: risk stratification based on wound, ischemia, and foot infection (WIfI).

    PubMed

    Mills, Joseph L; Conte, Michael S; Armstrong, David G; Pomposelli, Frank B; Schanzer, Andres; Sidawy, Anton N; Andros, George

    2014-01-01

    Critical limb ischemia, first defined in 1982, was intended to delineate a subgroup of patients with a threatened lower extremity primarily because of chronic ischemia. It was the intent of the original authors that patients with diabetes be excluded or analyzed separately. The Fontaine and Rutherford Systems have been used to classify risk of amputation and likelihood of benefit from revascularization by subcategorizing patients into two groups: ischemic rest pain and tissue loss. Due to demographic shifts over the last 40 years, especially a dramatic rise in the incidence of diabetes mellitus and rapidly expanding techniques of revascularization, it has become increasingly difficult to perform meaningful outcomes analysis for patients with threatened limbs using these existing classification systems. Particularly in patients with diabetes, limb threat is part of a broad disease spectrum. Perfusion is only one determinant of outcome; wound extent and the presence and severity of infection also greatly impact the threat to a limb. Therefore, the Society for Vascular Surgery Lower Extremity Guidelines Committee undertook the task of creating a new classification of the threatened lower extremity that reflects these important considerations. We term this new framework, the Society for Vascular Surgery Lower Extremity Threatened Limb Classification System. Risk stratification is based on three major factors that impact amputation risk and clinical management: Wound, Ischemia, and foot Infection (WIfI). The implementation of this classification system is intended to permit more meaningful analysis of outcomes for various forms of therapy in this challenging, but heterogeneous population. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  12. Vascular dysfunction in preeclampsia.

    PubMed

    Brennan, Lesley J; Morton, Jude S; Davidge, Sandra T

    2014-01-01

    Preeclampsia is a complex disorder which affects an estimated 5% of all pregnancies worldwide. It is diagnosed by hypertension in the presence of proteinuria after the 20th week of pregnancy and is a prominent cause of maternal morbidity and mortality. As delivery is currently the only known treatment, preeclampsia is also a leading cause of preterm delivery. Preeclampsia is associated with maternal vascular dysfunction, leading to serious cardiovascular risk both during and following pregnancy. Endothelial dysfunction, resulting in increased peripheral resistance, is an integral part of the maternal syndrome. While the cause of preeclampsia remains unknown, placental ischemia resulting from aberrant placentation is a fundamental characteristic of the disorder. Poor placentation is believed to stimulate the release of a number of factors including pro- and antiangiogenic factors and inflammatory activators into the maternal systemic circulation. These factors are critical mediators of vascular function and impact the endothelium in distinctive ways, including enhanced endothelial oxidative stress. The mechanisms of action and the consequences on the maternal vasculature will be discussed in this review. © 2013 John Wiley & Sons Ltd.

  13. Phosphate toxicity and vascular mineralization.

    PubMed

    Razzaque, Mohammed S

    2013-01-01

    Vascular calcification or mineralization is a major complication seen in patients with advanced stages of chronic kidney disease (CKD), and it is associated with markedly increased morbidity and mortality. Most of the CKD-related vascular mineralization is attributable to abnormal mineral ion metabolism. Elevated serum calcium and phosphate levels, along with increased calcium-phosphorus byproduct, and the use of active vitamin D metabolites are thought to be the predisposing factors for developing vascular mineralization in patients with CKD. Recent experimental studies have shown that vascular mineralization can be suppressed by reducing serum phosphate levels, even in the presence of extremely high serum calcium and 1,25-dihydroxyvitamin D levels, indicating that reducing 'phosphate toxicity' should be the important therapeutic priority in CKD patients for minimizing the risk of developing vascular mineralization and the disease progression. Copyright © 2013 S. Karger AG, Basel.

  14. [Advance in study of vascular endothelial cell and smooth muscle cell co-culture system].

    PubMed

    Li, Yujie; Yang, Qing; Weng, Xiaogang; Chen, Ying; Ruan, Congxiao; Li, Dan; Zhu, Xiaoxing

    2012-02-01

    The interactions between endothelial cells (EC) and smooth muscle cells (SMC) contribute to vascular physiological functions and also cause the occurrence and development of different kinds of diseases. Currently, EC-SMC co-culture model is the best way to study the interactions between the two kinds of cells. This article summarizes existing EC-SMC co-culture models and their effects on the structure and functions of the two kinds of cells. Microscopically speaking, it provides a basis for in-depth studies on their interactions as well as a reference for the establishment of in vitro EC-SMC co-culture system that is closer to organic physiology or pathology state.

  15. Effects of alpha-lipoic acid on spatial learning and memory, oxidative stress, and central cholinergic system in a rat model of vascular dementia.

    PubMed

    Zhao, Ran-Ran; Xu, Fei; Xu, Xiao-Chen; Tan, Guo-Jun; Liu, Liang-Min; Wu, Ning; Zhang, Wen-Zhong; Liu, Ji-Xiang

    2015-02-05

    Brain oxidative stress due to chronic cerebral hypoperfusion was considered to be the major risk factor in the pathogenesis of vascular dementia. In this study, we investigated the protective efficacy of alpha-lipoic acid, an antioxidant, against vascular dementia in rats, as well as the potential mechanism. Bilateral common carotid arteries occlusion (BCCAO) induced severe cognitive deficits tested by Morris water maze (MWM), along with oxidative stress and disturbance of central cholinergic system. However, administration of alpha-lipoic acid (50mg/kg, i.p.) for 28 days significantly restored cognitive deficits induced by BCCAO. Biochemical determination revealed that alpha-lipoic acid markedly decreased the production of malondialdehyde (MDA) and the generation of reactive oxidative species (ROS), and increased the level of reduced glutathione (GSH) in the hippocampal tissue. Additionally, alpha-lipoic acid raised the level of acetylcholine (ACh) and choline acetyltransferase (ChAT) and decreased the activity of acetycholinesterase (AChE) in the hippocampus. These results indicated that treatment with alpha-lipoic acid significantly improved behavioral alterations, protected against oxidative stress, and restored central cholinergic system in the rat model of vascular dementia induced by BCCAO. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. ALDOSTERONE DYSREGULATION WITH AGING PREDICTS RENAL-VASCULAR FUNCTION AND CARDIO-VASCULAR RISK

    PubMed Central

    Brown, Jenifer M.; Underwood, Patricia C.; Ferri, Claudio; Hopkins, Paul N.; Williams, Gordon H.; Adler, Gail K.; Vaidya, Anand

    2014-01-01

    Aging and abnormal aldosterone regulation are both associated with vascular disease. We hypothesized that aldosterone dysregulation influences the age-related risk of renal- and cardio-vascular disease. We conducted an analysis of 562 subjects who underwent detailed investigations under conditions of liberal and restricted dietary sodium intake (1,124 visits) in a Clinical Research Center. Aldosterone regulation was characterized by the ratio of maximal suppression-to-stimulation (supine serum aldosterone on a liberal sodium diet divided by the same measure on a restricted sodium diet). We previously demonstrated that higher levels of this Sodium-modulated Aldosterone Suppression-Stimulation Index (SASSI) indicate greater aldosterone dysregulation. Renal plasma flow (RPF) was determined via p-aminohippurate clearance to assess basal renal hemodynamics, and the renal-vascular responses to dietary sodium manipulation and angiotensin II (AngII) infusion. Cardiovascular risk was calculated using the Framingham Risk Score. In univariate linear regression, older age (β= -4.60, p<0.0001) and higher SASSI (β= -58.63, p=0.001) predicted lower RPF and a blunted RPF response to sodium loading and AngII infusion. We observed a continuous, independent, multivariate-adjusted interaction between age and SASSI, where the inverse relationship between SASSI and RPF was most apparent with older age (p<0.05). Higher SASSI and lower RPF independently predicted higher Framingham Risk Score (p<0.0001) and together displayed an additive effect. Aldosterone regulation and age may interact to mediate renal-vascular disease. Our findings suggest that the combination of aldosterone dysregulation and renal-vascular dysfunction could additively increase the risk of future cardiovascular outcomes; therefore, aldosterone dysregulation may represent a modifiable mechanism of age-related vascular disease. PMID:24664291

  17. Vascular aging: Chronic oxidative stress and impairment of redox signaling—consequences for vascular homeostasis and disease

    PubMed Central

    Bachschmid, Markus M.; Schildknecht, Stefan; Matsui, Reiko; Zee, Rebecca; Haeussler, Dagmar; Cohen, Richard A.; Pimental, David; van der Loo, Bernd

    2013-01-01

    Characteristic morphological and molecular alterations such as vessel wall thickening and reduction of nitric oxide occur in the aging vasculature leading to the gradual loss of vascular homeostasis. Consequently, the risk of developing acute and chronic cardiovascular diseases increases with age. Current research of the underlying molecular mechanisms of endothelial function demonstrates a duality of reactive oxygen and nitrogen species in contributing to vascular homeostasis or leading to detrimental effects when formed in excess. Furthermore, changes in function and redox status of vascular smooth muscle cells contribute to age-related vascular remodeling. The age-dependent increase in free radical formation causes deterioration of the nitric oxide signaling cascade, alters and activates prostaglandin metabolism, and promotes novel oxidative posttranslational protein modifications that interfere with vascular and cell signaling pathways. As a result, vascular dysfunction manifests. Compensatory mechanisms are initially activated to cope with age-induced oxidative stress, but become futile, which results in irreversible oxidative modifications of biological macromolecules. These findings support the ‘free radical theory of aging’ but also show that reactive oxygen and nitrogen species are essential signaling molecules, regulating vascular homeostasis. PMID:22380696

  18. Consensus recommendations for essential vascular care in low- and middle-income countries

    PubMed Central

    Stewart, Barclay T; Gyedu, Adam; Giannou, Christos; Mishra, Brijesh; Rich, Norman; Wren, Sherry; Mock, Charles; Kushner, Adam L

    2016-01-01

    Introduction Many low- and middle-income countries (LMICs) are ill equipped to care for the large and growing burden of vascular conditions. We aimed to develop essential vascular care recommendations that would be feasible for implementation at nearly every setting worldwide, regardless of national income. Methods The normative Delphi method was used to achieve consensus on essential vascular care resources among 27 experts in multiple areas of vascular care and public health, as well as with experience in LMIC healthcare. Five anonymous, iterative rounds of survey with controlled feedback and a statistical response were used to reach consensus on essential vascular care resources. Results The matrices provide recommendations for 92 vascular care resources at each of the four levels of care in most LMICs (i.e. primary health centers, and first-level, referral, and tertiary hospitals). The recommendations include both essential and desirable resources and encompass the following categories: screening, counseling, and evaluation; diagnostics; medical care; surgical care; equipment and supplies; and medications. Conclusion The resources recommended have the potential to improve LMIC healthcare systems’ ability to respond to the large and growing burden of vascular conditions. Many of these resources can be provided with thoughtful planning and organization without significant increases in cost. However, the resources must be incorporated into a framework that includes surveillance of vascular conditions, monitoring and evaluation of vascular capacity and care, a well functioning pre- and inter-hospital transport system, and vascular training for both existing and future healthcare providers. PMID:27432199

  19. Acceleration of vascularized bone tissue-engineered constructs in a large animal model combining intrinsic and extrinsic vascularization.

    PubMed

    Weigand, Annika; Beier, Justus P; Hess, Andreas; Gerber, Thomas; Arkudas, Andreas; Horch, Raymund E; Boos, Anja M

    2015-05-01

    During the last decades, a range of excellent and promising strategies in Bone Tissue Engineering have been developed. However, the remaining major problem is the lack of vascularization. In this study, extrinsic and intrinsic vascularization strategies were combined for acceleration of vascularization. For optimal biomechanical stability of the defect site and simplifying future transition into clinical application, a primary stable and approved nanostructured bone substitute in clinically relevant size was used. An arteriovenous (AV) loop was microsurgically created in sheep and implanted, together with the bone substitute, in either perforated titanium chambers (intrinsic/extrinsic) for different time intervals of up to 18 weeks or isolated Teflon(®) chambers (intrinsic) for 18 weeks. Over time, magnetic resonance imaging and micro-computed tomography (CT) analyses illustrate the dense vascularization arising from the AV loop. The bone substitute was completely interspersed with newly formed tissue after 12 weeks of intrinsic/extrinsic vascularization and after 18 weeks of intrinsic/extrinsic and intrinsic vascularization. Successful matrix change from an inorganic to an organic scaffold could be demonstrated in vascularized areas with scanning electron microscopy and energy dispersive X-ray spectroscopy. Using the intrinsic vascularization method only, the degradation of the scaffold and osteoclastic activity was significantly lower after 18 weeks, compared with 12 and 18 weeks in the combined intrinsic-extrinsic model. Immunohistochemical staining revealed an increase in bone tissue formation over time, without a difference between intrinsic/extrinsic and intrinsic vascularization after 18 weeks. This study presents the combination of extrinsic and intrinsic vascularization strategies for the generation of an axially vascularized bone substitute in clinically relevant size using a large animal model. The additional extrinsic vascularization promotes tissue

  20. Social media in vascular surgery.

    PubMed

    Indes, Jeffrey E; Gates, Lindsay; Mitchell, Erica L; Muhs, Bart E

    2013-04-01

    There has been a tremendous growth in the use of social media to expand the visibility of various specialties in medicine. The purpose of this paper is to describe the latest updates on some current applications of social media in the practice of vascular surgery as well as existing limitations of use. This investigation demonstrates that the use of social networking sites appears to have a positive impact on vascular practice, as is evident through the incorporation of this technology at the Cleveland Clinic and by the Society for Vascular Surgery into their approach to patient care and physician communication. Overall, integration of social networking technology has current and future potential to be used to promote goals, patient awareness, recruitment for clinical trials, and professionalism within the specialty of vascular surgery. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  1. Caffeine's Vascular Mechanisms of Action

    PubMed Central

    Echeverri, Darío; Montes, Félix R.; Cabrera, Mariana; Galán, Angélica; Prieto, Angélica

    2010-01-01

    Caffeine is the most widely consumed stimulating substance in the world. It is found in coffee, tea, soft drinks, chocolate, and many medications. Caffeine is a xanthine with various effects and mechanisms of action in vascular tissue. In endothelial cells, it increases intracellular calcium stimulating the production of nitric oxide through the expression of the endothelial nitric oxide synthase enzyme. Nitric oxide is diffused to the vascular smooth muscle cell to produce vasodilation. In vascular smooth muscle cells its effect is predominantly a competitive inhibition of phosphodiesterase, producing an accumulation of cAMP and vasodilation. In addition, it blocks the adenosine receptors present in the vascular tissue to produce vasoconstriction. In this paper the main mechanisms of action of caffeine on the vascular tissue are described, in which it is shown that caffeine has some cardiovascular properties and effects which could be considered beneficial. PMID:21188209

  2. Highly controlled vascular syringes for pericardiocentesis.

    PubMed

    Ricciardi, Mark; Roldan, Carlos; Sibbitt, Randy; Sibbitt, Wilmer; Michael, Adrian; Palmer, Dennis

    2010-12-01

    The present study determined the utility and needle control characteristics of highly controlled vascular syringes for image-guided pericardiocentesis. Vascular syringes have been integrated into invasive cardiovascular procedures with improved patient safety, but to date have not been used in pericardiocentesis. To address this issue, we determined the method of use of vascular syringes for pericardiocentesis. A vascular syringe with reciprocating plungers, the reciprocating procedure device (RPD syringe), replaced the corresponding 10 ml and 20 ml conventional syringes in a standard pericardiocentesis tray. The vascular syringe is controlled with one hand, and can either aspirate or inject by pushing the corresponding aspiration or injection plunger. Four hundred and thirty seven subjects underwent vascular syringe procedures. The linear displacement method was used to precisely measure control of the needle tip in millimeters (mm) in vascular syringes compared to conventional syringes in 20 individual operators. Relative to the corresponding 10 ml and 20 ml conventional syringes, vascular syringes significantly reduced unintended forward penetration of the needle tip by 44% (7.0 ± 4.3 mm; p < 0.0001) and 53% (10.1 ± 5.5 mm; p < 0.0001), respectively, and reduced unintended retraction of the needle by 56% (2.7 ± 2.2 mm; p < 0.001) and 60% (3.5 ± 2.5 mm; p < 0.001), respectively. During pericardiocentesis, the mechanical syringe permitted facile one-handed aspiration and maintained the operator's ability to clear the needle. In the 437 vascular syringe procedures, there were no complications, with an estimated cost savings of $10-65 per procedure. Vascular syringes improve needle control in pericardiocentesis, promote patient safety and permit one-handed aspiration and injection.

  3. Disparate cardio-cerebral vascular modulation during standing in multiple system atrophy and Parkinson disease.

    PubMed

    Xu, Wei-Hai; Wang, Han; Wang, Bo; Niu, Fu-Sheng; Gao, Shan; Cui, Li-Ying

    2009-01-15

    The dynamic variance of cerebral blood flow velocity (CBFV), monitored by transcranial doppler (TCD), can reveal the integrated effects of cardio-cerebral vascular autoregulation. We investigated the characteristics of CBFV curve during active standing in multiple system atrophy (MSA), Parkinson's disease (PD) and healthy volunteers. The CBFV curve of middle cerebral arteries was recorded using TCD in 22 patients with probable MSA; 20 PD patients and 20 volunteers matched for age. All individuals started in a supine posture, followed by abrupt standing for 2 min before returning to supine. The features of CBFV curve were compared among the groups. In the healthy volunteers, the CBFV decreased following standing up but quickly rebounded and reached the same or greater level as the supine baseline. Afterwards, the CBFV decreased abruptly to a sustained level, lower than the supine baseline, forming a spike wave that appeared in CBFV curve. This spike wave was present in 5/22 of MSA, significantly less than PD patients (18/20) and volunteers (20/20) (P<0.001). The CBFV decrease after standing showed no significant difference between MSA than PD (9+/-7 vs. 6+/-3 cm/s, P=0.163). The different pattern of CBFV curves during active standing suggests MSA may possess cardio-cerebral vascular modulation different from PD. The clinical value of the CBFV curve in differentiating MSA from PD needs further investigation.

  4. Pulmonary vascular dysfunction in ARDS

    PubMed Central

    2014-01-01

    Acute respiratory distress syndrome (ARDS) is characterised by diffuse alveolar damage and is frequently complicated by pulmonary hypertension (PH). Multiple factors may contribute to the development of PH in this setting. In this review, we report the results of a systematic search of the available peer-reviewed literature for papers that measured indices of pulmonary haemodynamics in patients with ARDS and reported on mortality in the period 1977 to 2010. There were marked differences between studies, with some reporting strong associations between elevated pulmonary arterial pressure or elevated pulmonary vascular resistance and mortality, whereas others found no such association. In order to discuss the potential reasons for these discrepancies, we review the physiological concepts underlying the measurement of pulmonary haemodynamics and highlight key differences between the concepts of resistance in the pulmonary and systemic circulations. We consider the factors that influence pulmonary arterial pressure, both in normal lungs and in the presence of ARDS, including the important effects of mechanical ventilation. Pulmonary arterial pressure, pulmonary vascular resistance and transpulmonary gradient (TPG) depend not alone on the intrinsic properties of the pulmonary vascular bed but are also strongly influenced by cardiac output, airway pressures and lung volumes. The great variability in management strategies within and between studies means that no unified analysis of these papers was possible. Uniquely, Bull et al. (Am J Respir Crit Care Med 182:1123–1128, 2010) have recently reported that elevated pulmonary vascular resistance (PVR) and TPG were independently associated with increased mortality in ARDS, in a large trial with protocol-defined management strategies and using lung-protective ventilation. We then considered the existing literature to determine whether the relationship between PVR/TPG and outcome might be causal. Although we could identify

  5. Tofacitinib ameliorates murine lupus and its associated vascular dysfunction

    PubMed Central

    Furumoto, Yasuko; Smith, Carolyne K.; Blanco, Luz; Zhao, Wenpu; Brooks, Stephen R.; Thacker, Seth G; Abdalrahman, Zarzour; Sciumè, Giuseppe; Tsai, Wanxia L.; Trier, Anna M.; Nunez, Leti; Mast, Laurel; Hoffmann, Victoria; Remaley, Alan T.; O'Shea, John J.

    2016-01-01

    Objectives Dysregulation of innate and adaptive immune responses contributes to the pathogenesis of systemic lupus erythematosus (SLE) and its associated premature vascular damage. To date, no drug targets both systemic inflammatory disease and the cardiovascular complications of SLE. Tofacitinib is a Janus kinase (JAK) inhibitor that blocks signaling downstream of multiple cytokines implicated in lupus pathogenesis. While clinical trials have shown that tofacitinib exhibits significant clinical efficacy in various autoimmune diseases, its role in SLE and on its associated vascular pathology remains to be characterized. Methods MRL/lpr lupus-prone mice received tofacitinib or vehicle by gavage for 6 weeks (therapeutic arm) or 8 weeks (preventive arm). Nephritis, skin inflammation, serum autoantibody levels and cytokines, mononuclear cell phenotype and gene expression, neutrophil extracellular trap (NET) release, endothelium-dependent vasorelaxation and endothelial differentiation were compared in treated and untreated mice. Results Treatment with tofacitinib led to significant improvement in measures of disease activity including nephritis, skin inflammation, and autoantibody production. In addition, tofacitinib treatment reduced serum levels of pro-inflammatory cytokines and interferon responses in splenocytes and kidney tissue. Tofacitinib also modulated NET formation and significantly increased endothelium-dependent vasorelaxation and endothelial differentiation. The drug was effective as both preventive and therapeutic strategies. Conclusions Tofacitinib modulates the innate and adaptive immune responses, ameliorates murine lupus and improves vascular function. These results indicate that JAK inhibitors have the potential to be beneficial in SLE and its associated vascular damage. PMID:27429362

  6. Tofacitinib Ameliorates Murine Lupus and Its Associated Vascular Dysfunction.

    PubMed

    Furumoto, Yasuko; Smith, Carolyne K; Blanco, Luz; Zhao, Wenpu; Brooks, Stephen R; Thacker, Seth G; Abdalrahman, Zarzour; Sciumè, Giuseppe; Tsai, Wanxia L; Trier, Anna M; Nunez, Leti; Mast, Laurel; Hoffmann, Victoria; Remaley, Alan T; O'Shea, John J; Kaplan, Mariana J; Gadina, Massimo

    2017-01-01

    Dysregulation of innate and adaptive immune responses contributes to the pathogenesis of systemic lupus erythematosus (SLE) and its associated premature vascular damage. No drug to date targets both systemic inflammatory disease and the cardiovascular complications of SLE. Tofacitinib is a JAK inhibitor that blocks signaling downstream of multiple cytokines implicated in lupus pathogenesis. While clinical trials have shown that tofacitinib exhibits significant clinical efficacy in various autoimmune diseases, its role in SLE and the associated vascular pathology remains to be characterized. MRL/lpr lupus-prone mice were administered tofacitinib or vehicle by gavage for 6 weeks (therapeutic arm) or 8 weeks (preventive arm). Nephritis, skin inflammation, serum levels of autoantibodies and cytokines, mononuclear cell phenotype and gene expression, neutrophil extracellular traps (NETs) release, endothelium-dependent vasorelaxation, and endothelial differentiation were compared in treated and untreated mice. Treatment with tofacitinib led to significant improvement in measures of disease activity, including nephritis, skin inflammation, and autoantibody production. In addition, tofacitinib treatment reduced serum levels of proinflammatory cytokines and interferon responses in splenocytes and kidney tissue. Tofacitinib also modulated the formation of NETs and significantly increased endothelium-dependent vasorelaxation and endothelial differentiation. The drug was effective in both preventive and therapeutic strategies. Tofacitinib modulates the innate and adaptive immune responses, ameliorates murine lupus, and improves vascular function. These results indicate that JAK inhibitors have the potential to be beneficial in SLE and its associated vascular damage. © 2016, American College of Rheumatology.

  7. D-series resolvin attenuates vascular smooth muscle cell activation and neointimal hyperplasia following vascular injury

    PubMed Central

    Miyahara, Takuya; Runge, Sara; Chatterjee, Anuran; Chen, Mian; Mottola, Giorgio; Fitzgerald, Jonathan M.; Serhan, Charles N.; Conte, Michael S.

    2013-01-01

    Recent evidence suggests that specialized lipid mediators derived from polyunsaturated fatty acids control resolution of inflammation, but little is known about resolution pathways in vascular injury. We sought to determine the actions of D-series resolvin (RvD) on vascular smooth muscle cell (VSMC) phenotype and vascular injury. Human VSMCs were treated with RvD1 and RvD2, and phenotype was assessed by proliferation, migration, monocyte adhesion, superoxide production, and gene expression assays. A rabbit model of arterial angioplasty with local delivery of RvD2 (10 nM vs. vehicle control) was employed to examine effects on vascular injury in vivo. Local generation of proresolving lipid mediators (LC-MS/MS) and expression of RvD receptors in the vessel wall were assessed. RvD1 and RvD2 produced dose-dependent inhibition of VSMC proliferation, migration, monocyte adhesion, superoxide production, and proinflammatory gene expression (IC50≈0.1–1 nM). In balloon-injured rabbit arteries, cell proliferation (51%) and leukocyte recruitment (41%) were reduced at 3 d, and neointimal hyperplasia was attenuated (29%) at 28 d by RvD2. We demonstrate endogenous biosynthesis of proresolving lipid mediators and expression of receptors for RvD1 in the artery wall. RvDs broadly reduce VSMC responses and modulate vascular injury, suggesting that local activation of resolution mechanisms expedites vascular homeostasis.—Miyahara, T., Runge, S., Chatterjee, A., Chen, M., Mottola, G., Fitzgerald, J. M., Serhan, C. N., Conte, M. S. D-series resolvin attenuates vascular smooth muscle cell activation and neointimal hyperplasia following vascular injury. PMID:23407709

  8. Vascular, glial, and lymphatic immune gateways of the central nervous system.

    PubMed

    Engelhardt, Britta; Carare, Roxana O; Bechmann, Ingo; Flügel, Alexander; Laman, Jon D; Weller, Roy O

    2016-09-01

    Immune privilege of the central nervous system (CNS) has been ascribed to the presence of a blood-brain barrier and the lack of lymphatic vessels within the CNS parenchyma. However, immune reactions occur within the CNS and it is clear that the CNS has a unique relationship with the immune system. Recent developments in high-resolution imaging techniques have prompted a reassessment of the relationships between the CNS and the immune system. This review will take these developments into account in describing our present understanding of the anatomical connections of the CNS fluid drainage pathways towards regional lymph nodes and our current concept of immune cell trafficking into the CNS during immunosurveillance and neuroinflammation. Cerebrospinal fluid (CSF) and interstitial fluid are the two major components that drain from the CNS to regional lymph nodes. CSF drains via lymphatic vessels and appears to carry antigen-presenting cells. Interstitial fluid from the CNS parenchyma, on the other hand, drains to lymph nodes via narrow and restricted basement membrane pathways within the walls of cerebral capillaries and arteries that do not allow traffic of antigen-presenting cells. Lymphocytes targeting the CNS enter by a two-step process entailing receptor-mediated crossing of vascular endothelium and enzyme-mediated penetration of the glia limitans that covers the CNS. The contribution of the pathways into and out of the CNS as initiators or contributors to neurological disorders, such as multiple sclerosis and Alzheimer's disease, will be discussed. Furthermore, we propose a clear nomenclature allowing improved precision when describing the CNS-specific communication pathways with the immune system.

  9. [Menopause: Hypertension and vascular disease].

    PubMed

    Zilberman, J M

    Hypertension is the main cardiovascular risk factor affecting 25% of women. Hormone changes and hypertension after menopause may lead to higher target organ damage and cardiovascular disease such as increased arterial stiffness, coronary diseases, chronic heart failure and stroke. The physiopathological mechanisms involved in the development of hypertension and cardiovascular diseases in menopausal women are controversial. There are pharmacokinetic and pharmacodynamic differences in both sexes, the women have more coughing when using the converting-enzyme inhibitors, more cramps when using thiazide diuretics and more oedema in the inferior limbs when using calcium antagonists. The aim of this review is to analyse possible physiopathological mechanisms involved in hypertension after menopause and to gain a better understanding of the biological effects mediated by vascular ageing in women when the level of oestrogen protective effect decreases over the vascular system. Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Vascular anomalies and the growth of limbs: a review.

    PubMed

    Enjolras, Odile; Chapot, René; Merland, Jean Jacques

    2004-11-01

    Growth of the limb in a child can be impaired, with the coexistence of a vascular malformation. In these vascular bone syndromes, altered growth is manifest as overgrowth or hypotrophy. The vascular malformation is usually complex and gets progressively worse with time. The two types of vascular anomalies in limbs, fast-flow and slow-flow, can be associated with limb length discrepancies. The fast-flow vascular malformations together with arteriovenous fistulae are part of Parkes Weber syndrome, characterized by congenital red cutaneous staining, hypertrophy in girth and increasing of limb length, lymphedema, increasing skin alterations due to a distal vascular steal, and pain, all of which develop during childhood. Treatment is generally conservative. An affected lower extremity can be complicated by pelvic tilting and scoliosis because leg length discrepancy may reach 10 cm. To avoid such a course, stapling epiphysiodesis of the knee cartilages is often performed, but this orthopedic procedure may augment the worsening of the arterial venous malformation in the limb. Therefore, less aggressive orthopedic management is preferable. Slow-flow vascular anomalies associated with limb growth alteration include (1) a diffuse capillary malformation (port-wine stain) with congenital hypertrophy of the involved extremity which is non-progressive; (2) purely venous malformations invading skin, muscles and joints, with pain, functional impairment, a chronic localized intravascular coagulopathy requiring distinctive management, and usually a slight undergrowth of the affected extremity and progressing amyotrophy; (3) the triad of a port-wine stain, anomalous veins and overgrowth of the limb, often known as Klippel-Trenaunay syndrome, which requires orthopedic management to decide the optimal timing for epiphysiodesis (i.e. when leg length discrepancy is >2.5 cm). Varicose veins are sometimes surgically removed after ultrasonographic and Doppler evaluation has confirmed a

  11. Laceration of the Common Femoral Artery Following Deployment of the StarClose{sup TM} Vascular Closure System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gonsalves, Michael, E-mail: drmag1975@gmail.com; Walkden, Miles, E-mail: rwalkden@nhs.net; Belli, Anna Maria, E-mail: Anna.Belli@stgeorges.nhs.u

    2008-07-15

    StarClose is a novel arterial closure device which achieves hemostasis, following arteriotomy, via a nitinol clip deployed on the outer arterial wall. Since its introduction to the market, several studies have shown StarClose to be both safe and effective, with few major complications encountered. We report a case of common femoral artery laceration following deployment of the StarClose vascular closure system. We conclude that the injury occurred secondary to intravascular misplacement of the nitinol clip.

  12. Adverse Outcome Pathway for Embryonic Vascular Disruption and Alternative Methods to Identify Chemical Vascular Disruptors During Development

    EPA Science Inventory

    Chemically induced vascular toxicity during embryonic development can result in a wide range of adverse prenatal outcomes. We used information from genetic mouse models linked to phenotypic outcomes and a vascular toxicity knowledge base to construct an embryonic vascular disrupt...

  13. Influence of Fasciola hepatica on Serum Biochemical Parameters and Vascular and Biliary System of Sheep Liver

    PubMed Central

    Hodžić, A; Zuko, A; Avdić, R; Alić, A; Omeragić, J; Jažić, A

    2013-01-01

    Background The aim of this study was to evaluate the functional capacity of the liver based on the activity of specific enzymes and bilirubin in serum and also to investigate the influence of mechanical and toxic effects of Fasciola hepatica on the structures of the blood vessels and biliary tract in the sheep liver. Methods Blood samples and liver of 63 indigenous sheep of Pramenka breed, slaughtered in the period from March to December 2009 were used. Based on parasitological findings in the liver, all animals were divided into two groups: control (n = 34) and infected group (n = 29). For investigation and description of pathological changes in sheep liver, naturally infected with F. hepatica, corrosion cast technique was used. Results Biochemical analysis of tested parameters showed a significant elevation (P≤0.05) of serum gamma-glutamyl transferase (GGT), total bilirubin (TBIL) and direct bilirubin (DBIL) in infected sheep group comparing with the control group. No significant differences were observed for activity of aspartate aminotranferase (AST) between groups. Vascular and biliary systems of the liver were found to be affected. Conclusion Results of biochemical analysis are consistent with pathological findings and measuring of tested parameters could be used in early diagnosis of sheep fasciolosis and to test the effectiveness of anthelmintic therapy. Corrosion cast technique is very useful for investigation of pathological changes and neoangiogenesis of vascular and biliary system in sheep liver, caused by mechanical and toxic effects of F. hepatica. PMID:23682266

  14. Hypertonic Saline Reduces Vascular Leakage in a Mouse Model of Severe Dengue

    PubMed Central

    Tan, Kar Wai; Angeli, Veronique; Moochhala, Shabbir; Ooi, Eng Eong; Alonso, Sylvie

    2013-01-01

    Dengue (DEN) is a mosquito-borne viral disease and represents a serious public health threat and an economical burden throughout the tropics. Dengue clinical manifestations range from mild acute febrile illness to severe DEN hemorrhagic fever/DEN shock syndrome (DHF/DSS). Currently, resuscitation with large volumes of isotonic fluid remains the gold standard of care for DEN patients who develop vascular leakage and shock. Here, we investigated the ability of small volume of hypertonic saline (HTS) suspensions to control vascular permeability in a mouse model of severe DEN associated with vascular leakage. Several HTS treatment regimens were considered and our results indicated that a single bolus of 7.5% NaCl at 4 mL per kg of body weight administered at the onset of detectable vascular leakage rapidly and significantly reduced vascular leak for several days after injection. This transient reduction of vascular leakage correlated with reduced intestine and liver damage with restoration of the hepatic functions, and resulted in delayed death of the infected animals. Mechanistically, we showed that HTS did not directly impact on the viral titers but resulted in lower immune cells counts and decreased systemic levels of soluble mediators involved in vascular permeability. In addition, we demonstrated that neutrophils do not play a critical role in DEN-associated vascular leakage and that the therapeutic effect of HTS is not mediated by its impact on the neutrophil counts. Together our data indicate that HTS treatment can transiently but rapidly reduce dengue-associated vascular leakage, and support the findings of a recent clinical trial which evaluated the efficacy of a hypertonic suspension to impact on vascular permeability in DSS children. PMID:23637867

  15. Connexins and Pannexins in Vascular Function and Disease.

    PubMed

    Molica, Filippo; Figueroa, Xavier F; Kwak, Brenda R; Isakson, Brant E; Gibbins, Jonathan M

    2018-06-05

    Connexins (Cxs) and pannexins (Panxs) are ubiquitous membrane channel forming proteins that are critically involved in many aspects of vascular physiology and pathology. The permeation of ions and small metabolites through Panx channels, Cx hemichannels and gap junction channels confers a crucial role to these proteins in intercellular communication and in maintaining tissue homeostasis. This review provides an overview of current knowledge with respect to the pathophysiological role of these channels in large arteries, the microcirculation, veins, the lymphatic system and platelet function. The essential nature of these membrane proteins in vascular homeostasis is further emphasized by the pathologies that are linked to mutations and polymorphisms in Cx and Panx genes.

  16. Continuous exposure to low amplitude extremely low frequency electrical fields characterizing the vascular streaming potential alters elastin accumulation in vascular smooth muscle cells.

    PubMed

    Bergethon, Peter R; Kindler, Dean D; Hallock, Kevin; Blease, Susan; Toselli, Paul

    2013-07-01

    In normal development and pathology, the vascular system depends on complex interactions between cellular elements, biochemical molecules, and physical forces. The electrokinetic vascular streaming potential (EVSP) is an endogenous extremely low frequency (ELF) electrical field resulting from blood flowing past the vessel wall. While generally unrecognized, it is a ubiquitous electrical biophysical force to which the vascular tree is exposed. Extracellular matrix elastin plays a central role in normal blood vessel function and in the development of atherosclerosis. It was hypothesized that ELF fields of low amplitude would alter elastin accumulation, supporting a link between the EVSP and the biology of vascular smooth muscle cells. Neonatal rat aortic smooth muscle cell cultures were exposed chronically to electrical fields characteristic of the EVSP. Extracellular protein accumulation, DNA content, and electron microscopic (EM) evaluation were performed after 2 weeks of exposure. Stimulated cultures showed no significant change in cellular proliferation as measured by the DNA concentration. The per-DNA normalized protein in the extracellular matrix was unchanged while extracellular elastin accumulation decreased 38% on average. EM analysis showed that the stimulated cells had a 2.85-fold increase in mitochondrial number. These results support the formulation that ELF fields are a potential factor in both normal vessel biology and in the pathogenesis of atherosclerotic diseases including heart disease, stroke, and peripheral vascular disease. Copyright © 2013 Wiley Periodicals, Inc.

  17. Overgrowth syndromes with vascular anomalies.

    PubMed

    Blei, Francine

    2015-04-01

    Overgrowth syndromes with vascular anomalies encompass entities with a vascular anomaly as the predominant feature vs those syndromes with predominant somatic overgrowth and a vascular anomaly as a more minor component. The focus of this article is to categorize these syndromes phenotypically, including updated clinical criteria, radiologic features, evaluation, management issues, pathophysiology, and genetic information. A literature review was conducted in PubMed using key words "overgrowth syndromes and vascular anomalies" as well as specific literature reviews for each entity and supportive genetic information (e.g., somatic mosaicism). Additional searches in OMIM and Gene Reviews were conducted for each syndrome. Disease entities were categorized by predominant clinical features, known genetic information, and putative affected signaling pathway. Overgrowth syndromes with vascular anomalies are a heterogeneous group of disorders, often with variable clinical expression, due to germline or somatic mutations. Overgrowth can be focal (e.g., macrocephaly) or generalized, often asymmetrically (and/or mosaically) distributed. All germ layers may be affected, and the abnormalities may be progressive. Patients with overgrowth syndromes may be at an increased risk for malignancies. Practitioners should be attentive to patients having syndromes with overgrowth and vascular defects. These patients require proactive evaluation, referral to appropriate specialists, and in some cases, early monitoring for potential malignancies. Progress in identifying vascular anomaly-related overgrowth syndromes and their genetic etiology has been robust in the past decade and is contributing to genetically based prenatal diagnosis and new therapies targeting the putative causative genetic mutations. Copyright © 2015 Mosby, Inc. All rights reserved.

  18. Missile vascular injuries: 19-year experience.

    PubMed

    Ahanger, Abdul Gani; Wani, Mohd Lateef; Lone, Reyaz Ahmad; Singh, Shyam; Hussain, Zahur; Mir, Ishtiyak A; Irshad, Ifat; Ashraf, Hakeem Zubair; Dar, Abdul Majeed; Lone, Ghulam Nabi; Bhat, Mohammad Akbar; Sharma, Mukand Lal

    2010-03-01

    Missile vascular injuries have reached an epidemic proportion in Kashmir valley since the eruption of militancy. The present study was undertaken to analyze the mode, pattern, presentation, and management of missile vascular injuries. A retrospective study of patients with missile vascular injury from January 1990 to October 2008 was undertaken. Five hundred eighty patients with missile vascular injury were studied. All patients with vascular injury due to causes other than missiles were excluded from the study. Most of the patients were treated by interpositional saphenous vein graft or end-to-end anastomosis. The most common complication was wound infection (22.7%) followed by graft occlusion (3.8%). The amputation rate was 3.3% and was higher in patients with a delay of >6 hours to revascularization and associated fractures. Missile vascular injury requires prompt resuscitation and revascularization. Preoperative angiography is seldom necessary. Doppler study may sometimes be needed to aid in the diagnosis.

  19. Protective effect of crocin against apoptosis induced by subchronic exposure of the rat vascular system to diazinon.

    PubMed

    Razavi, Bibi Marjan; Hosseinzadeh, Hossein; Abnous, Khalil; Khoei, Alireza; Imenshahidi, Mohsen

    2016-07-01

    Research has suggested that natural antioxidant, crocin, an active ingredient of saffron, may protect against diazinon (DZN)-induced toxicity. Although increased production of lipid peroxidation by DZN in rat aorta has been shown previously, the effects of DZN on oxidative stress-induced apoptosis in vascular system have not been evaluated. In this study, the effect of crocin on DZN-induced apoptosis in rat vascular system was investigated. The rats were divided into 7 groups: corn oil (control), DZN (15 mg/kg/day, gavage), crocin (12.5, 25, and 50 mg/kg/day, intraperitoneally (i.p.)) + DZN, vitamin E (200 IU/kg, i.p., 3 days a week) + DZN, and crocin (50 mg/kg/day, i.p.). The treatments were continued for 4 weeks. Levels of apoptotic (Bax, caspase 3, and caspase 9) and antiapoptotic proteins (Bcl2) were analyzed by Western blotting. Transcript levels of Bax and Bcl2 genes were determined using quantitative real-time polymerase chain reaction. Results showed DZN-induced apoptosis by activation of caspase 9 and caspase 3 and by increasing the Bax/Bcl2 ratio (both protein and messenger RNA levels). Crocin and vitamin E inhibited apoptosis induced by DZN. In summary, subchronic exposure to DZN induced caspase-mediated apoptosis, and crocin reduced the toxic effects of DZN by inhibiting apoptosis in aortic tissue. © The Author(s) 2014.

  20. Integrated Fellowship in Vascular Surgery and Intervention Radiology

    PubMed Central

    Messina, Louis M.; Schneider, Darren B.; Chuter, Timothy A. M.; Reilly, Linda M.; Kerlan, Robert K.; LaBerge, Jeane M.; Wilson, Mark W.; Ring, Ernest J.; Gordon, Roy L.

    2002-01-01

    Objective To evaluate an integrated fellowship in vascular surgery and interventional radiology initiated to train vascular surgeons in endovascular techniques and to train radiology fellows in clinical aspects of vascular diseases. Summary Background Data The rapid evolution of endovascular techniques for the treatment of vascular diseases requires that vascular surgeons develop proficiency in these techniques and that interventional radiologists develop proficiency in the clinical evaluation and management of patients who are best treated with endovascular techniques. In response to this need the authors initiated an integrated fellowship in vascular surgery and interventional radiology and now report their interim results. Methods Since 1999 vascular fellows and radiology fellows performed an identical year-long fellowship in interventional radiology. During the fellowship, vascular surgery and radiology fellows perform both vascular and nonvascular interventional procedures. Both vascular surgery and radiology-based fellows spend one quarter of the year on the vascular service performing endovascular aortic aneurysm repairs and acquiring clinical experience in the vascular surgery inpatient and outpatient services. Vascular surgery fellows then complete an additional year-long fellowship in vascular surgery. To evaluate the type and number of interventional radiology procedures, the authors analyzed records of cases performed by all interventional radiology and vascular surgery fellows from a prospectively maintained database. The attitudes of vascular surgery and interventional radiology faculty and fellows toward the integrated fellowship were surveyed using a formal questionnaire. Results During the fellowship each fellow performed an average of 1,201 procedures, including 808 vascular procedures (236 diagnostic angiograms, 70 arterial interventions, 59 diagnostic venograms, 475 venous interventions, and 43 hemodialysis graft interventions) and 393

  1. Vascular knowledge in medieval times was the turning point for the humanistic trend.

    PubMed

    Ducasse, E; Speziale, F; Baste, J C; Midy, D

    2006-06-01

    Knowledge of the history of our surgical specialty may broaden our viewpoint for everyday practice. We illustrate the scientific progress made in medieval times relevant to the vascular system and blood circulation, progress made despite prevailing religious and philosophical dogma. We located all articles concerning vascular knowledge and historical reviews in databases such as MEDLINE, EMBASE and the database of abstracts of reviews (DARE). We also explored the database of the register from the French National Library, the French Medical Inter-University (BIUM), the Italian National Library and the French and Italian Libraries in the Vatican. All data were collected and analysed in chronological order. Medieval vascular knowledge was inherited from Greek via Byzantine and Arabic writings, the first controversies against the recognized vascular schema emanating from an Arabian physician in the 13th century. Dissection was forbidden and clerical rules instilled a fear of blood. Major contributions to scientific progress in the vascular field in medieval times came from Ibn-al-Nafis and Harvey. Vascular specialists today may feel proud to recall that once religious dogma declined in early medieval times, vascular anatomic and physiological discoveries led the way to scientific progress.

  2. 21 CFR 870.3250 - Vascular clip.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vascular clip. 870.3250 Section 870.3250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3250 Vascular clip. (a) Identification. A vascular...

  3. 21 CFR 870.3250 - Vascular clip.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vascular clip. 870.3250 Section 870.3250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3250 Vascular clip. (a) Identification. A vascular...

  4. Vitamin D in Vascular Calcification: A Double-Edged Sword?

    PubMed

    Wang, Jeffrey; Zhou, Jimmy J; Robertson, Graham R; Lee, Vincent W

    2018-05-22

    Vascular calcification (VC) as a manifestation of perturbed mineral balance, is associated with aging, diabetes and kidney dysfunction, as well as poorer patient outcomes. Due to the current limited understanding of the pathophysiology of vascular calcification, the development of effective preventative and therapeutic strategies remains a significant clinical challenge. Recent evidence suggests that traditional risk factors for cardiovascular disease, such as left ventricular hypertrophy and dyslipidaemia, fail to account for clinical observations of vascular calcification. Therefore, more complex underlying processes involving physiochemical changes to mineral balance, vascular remodelling and perturbed hormonal responses such as parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF-23) are likely to contribute to VC. In particular, VC resulting from modifications to calcium, phosphate and vitamin D homeostasis has been recently elucidated. Notably, deregulation of vitamin D metabolism, dietary calcium intake and renal mineral handling are associated with imbalances in systemic calcium and phosphate levels and endothelial cell dysfunction, which can modulate both bone and soft tissue calcification. This review addresses the current understanding of VC pathophysiology, with a focus on the pathogenic role of vitamin D that has provided new insights into the mechanisms of VC.

  5. Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

    PubMed

    Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

    2017-08-17

    Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

  6. Lack of sensitivity of measurements of Vd/Vt at rest and during exercise in detection of hemodynamically significant pulmonary vascular abnormalities in collagen vascular disease.

    PubMed

    Mohsenifar, Z; Tashkin, D P; Levy, S E; Bjerke, R D; Clements, P J; Furst, D

    1981-05-01

    Wasted ventilation fraction (Vd/Vt) normally declines substantially during exercise in persons without lung disease. Failure of Vd/Vt to decrease during exercise has been reported to be one of the earliest abnormalities in patients with dyspnea caused by pulmonary vaso-occlusive disease, suggesting that measurement of Vd/Vt at rest and during exercise are useful in the diagnosis of pulmonary vascular disorders. We studied pulmonary hemodynamic and Vd/Vt responses to exercise in 11 patients in the supine position with suspected pulmonary vascular involvement caused by progressive systemic sclerosis, systemic lupus erythematosus, or recurrent pulmonary emboli, 10 of whom had dyspnea at rest and/or on exertion. In contrast to previous reports of no change or an increase in Vd/Vt during exercise in patients with pulmonary vascular disease, we found Vd/Vt to decrease significantly during exercise in 8 of 9 patients in whom mean pulmonary artery pressures were abnormally elevated at rest and/or during exercise. Our findings suggest that normal responses of Vd/Vt to exercise do not exclude hemodynamically significant pulmonary vaso-occlusive disease.

  7. Vascular signaling abnormalities in Alzheimer disease.

    PubMed

    Grammas, Paula; Sanchez, Alma; Tripathy, Debjani; Luo, Ester; Martinez, Joseph

    2011-08-01

    Our laboratory has documented that brain microvessels derived from patients with Alzheimer disease (AD) express or release a myriad of factors that have been implicated in vascular activation and angiogenesis. In addition, we have documented that signaling cascades associated with vascular activation and angiogenesis are upregulated in AD-derived brain microvessels. These results are consistent with emerging data suggesting that factors and processes characteristic of vascular activation and angiogenesis are found in the AD brain. Despite increases in proangiogenic factors and signals in the AD brain, however, evidence for increased vascularity in AD is lacking. Cerebral hypoperfusion/hypoxia, a potent stimulus for vascular activation and angiogenesis, triggers hypometabolic, cognitive, and degenerative changes in the brain. In our working model, hypoxia stimulates the angiogenic process; yet, there is no new vessel growth. Therefore, there are no feedback signals to shut off vascular activation, and endothelial cells become irreversibly activated. This activation results in release of a large number of proteases, inflammatory proteins, and other gene products with biologic activity that can injure or kill neurons. Pathologic activation of brain vasculature may contribute noxious mediators that lead to neuronal injury and disease processes in AD brains. This concept is supported by preliminary experiments in our laboratory, which show that pharmacologic blockade of vascular activation improves cognitive function in an animal model of AD. Thus, "vascular activation" could be a novel, unexplored therapeutic target in AD.

  8. Peripheral arteriovenous fistula as vascular access for long-term chemotherapy.

    PubMed

    Kovalyov, Oleksiy O; Kostyuk, Oleksandr G; Tkachuk, Tetyana V

    To provide long-term vascular access in clinical oncology peripheral forearm veins (up to 95% of patients in Ukraine), central venous access and "complete implanted vascular systems" are used most often. Many oncology patients have contraindications to catheterization of superior vena cava. Besides, exploitation of central veins is associated with potential technical and infectious complications. The aim - to study short-term and long-term results of arteriovenous fistula exploitation as vascular access for continuous anticancer therapy. Peripheral venous bed status in 41 oncology patients taking long-term chemotherapy treatment is analyzed in the article. Doppler sonography, morphologic and immune histochemical analyses were used in the study. Doppler sonography found qualitative and quantitative changes in forearm veins at different time periods after initiation of chemotherapy in the majority of patients. The major morphologic manifestations of venous wall damage were chemical phlebitis, local or extended hardening of venous wall, venous thrombosis and extravasations with necrosis and subsequent paravasal tissue sclerosis. Alternative vascular access created in 12 patients completely met the adequacy criteria (safety, multiple use, longevity, realization of the designed therapy program). The conclusion was made about inapplicability of forearm veins for long-term administration of cytostatic agents. If it is impossible to use central veins, arteriovenous fistula can become an alternative vascular access.

  9. Vascular Access Tracking System: a Web-Based Clinical Tracking Tool for Identifying Catheter Related Blood Stream Infections in Interventional Radiology Placed Central Venous Catheters.

    PubMed

    Morrison, James; Kaufman, John

    2016-12-01

    Vascular access is invaluable in the treatment of hospitalized patients. Central venous catheters provide a durable and long-term solution while saving patients from repeated needle sticks for peripheral IVs and blood draws. The initial catheter placement procedure and long-term catheter usage place patients at risk for infection. The goal of this project was to develop a system to track and evaluate central line-associated blood stream infections related to interventional radiology placement of central venous catheters. A customized web-based clinical database was developed via open-source tools to provide a dashboard for data mining and analysis of the catheter placement and infection information. Preliminary results were gathered over a 4-month period confirming the utility of the system. The tools and methodology employed to develop the vascular access tracking system could be easily tailored to other clinical scenarios to assist in quality control and improvement programs.

  10. Pediatric Interventional Radiology: Vascular Interventions.

    PubMed

    Kandasamy, Devasenathipathy; Gamanagatti, Shivanand; Gupta, Arun Kumar

    2016-07-01

    Pediatric interventional radiology (PIR) comprises a range of minimally invasive diagnostic and therapeutic procedures that are performed using image guidance. PIR has emerged as an essential adjunct to various surgical and medical conditions. Over the years, technology has undergone dramatic and continuous evolution, making this speciality grow. In this review, the authors will discuss various vascular interventional procedures undertaken in pediatric patients. It is challenging for the interventional radiologist to accomplish a successful interventional procedure. There are many vascular interventional radiology procedures which are being performed and have changed the way the diseases are managed. Some of the procedures are life saving and have become the treatment of choice in those patients. The future is indeed bright for the practice and practitioners of pediatric vascular and non-vascular interventions. As more and more of the procedures that are currently being performed in adults get gradually adapted for use in the pediatric population, it may be possible to perform safe and successful interventions in many of the pediatric vascular lesions that are otherwise being referred for surgery.

  11. Vascular corrosion casting of normal and pre-eclamptic placentas.

    PubMed

    Yin, Geping; Chen, Ming; Li, Juan; Zhao, Xiaoli; Yang, Shujun; Li, Xiuyun; Yuan, Zheng; Wu, Aifang

    2017-12-01

    Pre-eclampsia is an important cause of maternal and fetal morbidity and mortality that is associated with decreased placental perfusion. In the present study, vascular corrosion casting was used to investigate the differences in structural changes of the fetoplacental vasculature between normal and pre-eclamptic placentas. An improved epoxy resin vascular casting technique was used in the present study. Casting media were infused into 40 normal and 40 pre-eclamptic placentas through umbilical arteries and veins in order to construct three dimensional fetoplacental vasculatures. The number of branches, diameter, morphology and peripheral artery-to-vein ratio were measured for each specimen. The results indicated that the venous system of normal placentas was divided into 5-7 grades of branches and the volume of the vascular bed was 155.5±45.3 ml. In severe pre-eclamptic placentas, the volume was 106.4±36.1 ml, which was significantly lower compared with normal placentas (P<0.01). The venous system of pre-eclamptic placentas was divided into 4-5 grades of branches, which was much more sparse compared with normal placentas. In additions, the diameters of grade 1-3 veins and grade 2-3 arteries were significantly smaller in severe pre-eclampsia (P<0.05). In conclusion, pre-eclamptic placentas displayed a decreased volume of vascular bed, smaller diameters of grade 1-3 veins and grade 2-3 arteries, and an increased peripheral artery-to-vein ratio, which may be a cause of the placental dysfunction during severe pre-eclampsia.

  12. Macro-to-micro cortical vascular imaging underlies regional differences in ischemic brain

    NASA Astrophysics Data System (ADS)

    Dziennis, Suzan; Qin, Jia; Shi, Lei; Wang, Ruikang K.

    2015-05-01

    The ability to non-invasively monitor and quantify hemodynamic responses down to the capillary level is important for improved diagnosis, treatment and management of neurovascular disorders, including stroke. We developed an integrated multi-functional imaging system, in which synchronized dual wavelength laser speckle contrast imaging (DWLS) was used as a guiding tool for optical microangiography (OMAG) to test whether detailed vascular responses to experimental stroke in male mice can be evaluated with wide range sensitivity from arteries and veins down to the capillary level. DWLS enabled rapid identification of cerebral blood flow (CBF), prediction of infarct area and hemoglobin oxygenation over the whole mouse brain and was used to guide the OMAG system to hone in on depth information regarding blood volume, blood flow velocity and direction, vascular architecture, vessel diameter and capillary density pertaining to defined regions of CBF in response to ischemia. OMAG-DWLS is a novel imaging platform technology to simultaneously evaluate multiple vascular responses to ischemic injury, which can be useful in improving our understanding of vascular responses under pathologic and physiological conditions, and ultimately facilitating clinical diagnosis, monitoring and therapeutic interventions of neurovascular diseases.

  13. Three-dimensional Hessian matrix-based quantitative vascular imaging of rat iris with optical-resolution photoacoustic microscopy in vivo

    NASA Astrophysics Data System (ADS)

    Zhao, Huangxuan; Wang, Guangsong; Lin, Riqiang; Gong, Xiaojing; Song, Liang; Li, Tan; Wang, Wenjia; Zhang, Kunya; Qian, Xiuqing; Zhang, Haixia; Li, Lin; Liu, Zhicheng; Liu, Chengbo

    2018-04-01

    For the diagnosis and evaluation of ophthalmic diseases, imaging and quantitative characterization of vasculature in the iris are very important. The recently developed photoacoustic imaging, which is ultrasensitive in imaging endogenous hemoglobin molecules, provides a highly efficient label-free method for imaging blood vasculature in the iris. However, the development of advanced vascular quantification algorithms is still needed to enable accurate characterization of the underlying vasculature. We have developed a vascular information quantification algorithm by adopting a three-dimensional (3-D) Hessian matrix and applied for processing iris vasculature images obtained with a custom-built optical-resolution photoacoustic imaging system (OR-PAM). For the first time, we demonstrate in vivo 3-D vascular structures of a rat iris with a the label-free imaging method and also accurately extract quantitative vascular information, such as vessel diameter, vascular density, and vascular tortuosity. Our results indicate that the developed algorithm is capable of quantifying the vasculature in the 3-D photoacoustic images of the iris in-vivo, thus enhancing the diagnostic capability of the OR-PAM system for vascular-related ophthalmic diseases in vivo.

  14. The effect of interstitial pressure on therapeutic agent transport: coupling with the tumor blood and lymphatic vascular systems

    PubMed Central

    Wu, Min; Frieboes, Hermann B.; Chaplain, Mark A.J.; McDougall, Steven R.; Cristini, Vittorio; Lowengrub, John

    2014-01-01

    Vascularized tumor growth is characterized by both abnormal interstitial fluid flow and the associated interstitial fluid pressure (IFP). Here, we study the effect that these conditions have on the transport of therapeutic agents during chemotherapy. We apply our recently developed vascular tumor growth model which couples a continuous growth component with a discrete angiogenesis model to show that hypertensive IFP is a physical barrier that may hinder vascular extravasation of agents through transvascular fluid flux convection, which drives the agents away from the tumor. This result is consistent with previous work using simpler models without blood flow or lymphatic drainage. We consider the vascular/interstitial/lymphatic fluid dynamics to show that tumors with larger lymphatic resistance increase the agent concentration more rapidly while also experiencing faster washout. In contrast, tumors with smaller lymphatic resistance accumulate less agents but are able to retain them for a longer time. The agent availability (area-under-the curve, or AUC) increases for less permeable agents as lymphatic resistance increases, and correspondingly decreases for more permeable agents. We also investigate the effect of vascular pathologies on agent transport. We show that elevated vascular hydraulic conductivity contributes to the highest AUC when the agent is less permeable, but leads to lower AUC when the agent is more permeable. We find that elevated interstitial hydraulic conductivity contributes to low AUC in general regardless of the transvascular agent transport capability. We also couple the agent transport with the tumor dynamics to simulate chemotherapy with the same vascularized tumor under different vascular pathologies. We show that tumors with an elevated interstitial hydraulic conductivity alone require the strongest dosage to shrink. We further show that tumors with elevated vascular hydraulic conductivity are more hypoxic during therapy and that the

  15. Submillimeter spectra of 2-hydroxyacetonitrile (glycolonitrile; HOCH2CN) and its searches in GBT PRIMOS observations of Sgr B2(N)

    NASA Astrophysics Data System (ADS)

    Margulès, L.; McGuire, B. A.; Senent, M. L.; Motiyenko, R. A.; Remijan, A.; Guillemin, J. C.

    2017-05-01

    Context. Recent experimental works have studied the possible formation of hydroxyacetonitrile on astrophysical grains. It was formed from hydrogen cyanide (HCN) and formaldehyde (H2CO) in the presence of water under interstellar medium conditions. Because these precursor molecules are abundant, hydroxyacetonitrile is an excellent target for interstellar detection. Aims: Previous studies of the rotational spectra were limited to 40 GHz, resulting in an inaccurate line list when predicted up to the millimeter-wave range. We measured and analyzed its spectra up to 600 GHz to enable is searches using cutting-edge millimeter and submillimeter observatories. Methods: The molecule 2-hydroxyacetonitrile exhibits large amplitude motion that is due to the torsion of the hydroxyl group. The analysis of the spectra was made using the RAS formalism available in the SPFIT program with Watson's S-reduction Hamiltonians. Results: The submillimeter spectra of hydroxyacetonitrile, an astrophysically interesting molecule, were analyzed. More than 5000 lines were fitted with quantum number values reaching 75 and 25 for J and Ka, respectively. An accurate line list and partition function were provided. A search for hydroxyacetonitrile in publicly available GBT PRIMOS project, IRAM 30 m, and Herschel HEXOS observations of the Sgr B2(N) high-mass star-forming region resulted in a non-detection; upper limits to the column density were determined. Hydroxyacetonitrile fit is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/601/A50

  16. Amplatzer Vascular Plug Anchoring Technique to Stabilize the Delivery System for Microcoil Embolization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Onozawa, Shiro, E-mail: onozawa@nms.ac.jp; Murata, Satoru, E-mail: genji@nms.ac.jp; Mine, Takahiko, E-mail: takahikomine@gmail.com

    PurposeTo evaluate the feasibility of a novel embolization technique, the Amplatzer vascular plug (AVP) anchoring technique, to stabilize the delivery system for microcoil embolization.Materials and methodsThree patients were enrolled in this study, including two cases of internal iliac artery aneurysms and one case of internal iliac arterial occlusion prior to endovascular aortic repair. An AVP was used in each case for embolization of one target artery, and the AVP was left in place. The AVP detachment wire was then used as an anchor to stabilize the delivery system for microcoil embolization to embolize the second target artery adjacent to themore » first target artery. The microcatheter for the microcoils was inserted parallel to the AVP detachment wire in the guiding sheath or catheter used for the AVP.ResultsThe AVP anchoring technique was achieved and the microcatheter was easily advanced to the second target artery in all three cases.ConclusionThe AVP anchoring technique was found to be feasible to advance the microcatheter into the neighboring artery of an AVP-embolized artery.« less

  17. Modulation of vascular function by diet and exercise.

    PubMed

    Jennings, G L; Chin-Dusting, J P; Kingwell, B A; Dart, A M; Cameron, J; Esler, M; Lewis, T V

    1997-01-01

    Clinical research is conducted in free living individuals who are always subject to the influences on vascular function and the major cardiovascular regulators of their lifestyle. The purpose of this paper is to review some lifestyle influences on cardiovascular function, particularly the sympathetic nervous system and endothelially mediated vasodilatation. There are highly differentiated sympathetic responses to feeding, and to acute exercise. Over a longer period obesity has a typical pattern of sympathetic activity. Reduced dietary salt intake elicits profound localised increases in sympathetic activity to the kidney. Marine oil supplementation attenuates the sympathetic responses to psychological stress and improves endothelially mediated vasodilatation in hypercholesterolaemics. Exercise training reduced total noradrenaline spillover, the major beds affected being the renal and skeletal muscle. These examples illustrate the dynamic nature of vascular dilatation and that, like the sympathetic nervous system, it is modulated by short, medium and long term influences. In both cases there is regulation both at a local and systemic level. Habitual, and recent, lifestyle can exert important cardiovascular effects which must be taken into account in clinical and epidemiological research.

  18. Outcomes of truncal vascular injuries in children

    PubMed Central

    Allison, Nathan D.; Anderson, Christopher M.; Shah, Shinil K.; Lally, Kevin P.; Hayes-Jordan, Andrea; Tsao, Kuo-Jen; Andrassy, Richard J.; Cox, Charles S.

    2011-01-01

    Background Pediatric truncal vascular injuries occur infrequently and have a reported mortality rate of 30% to 50%. This report examines the demographics, mechanisms of injury, associated trauma, and outcome of patients presenting for the past 10 years at a single institution with truncal vascular injuries. Methods A retrospective review (1997-2006) of a pediatric trauma registry at a single institution was undertaken. Results Seventy-five truncal vascular injuries occurred in 57 patients (age, 12 ± 3 years); the injury mechanisms were penetrating in 37%. Concomitant injuries occurred with 76%, 62%, and 43% of abdominal, thoracic, and neck vascular injuries, respectively. Nonvascular complications occurred more frequently in patients with abdominal vascular injuries who were hemodynamically unstable on presentation. All patients with thoracic vascular injuries presenting with hemodynamic instability died. In patients with neck vascular injuries, 1 of 2 patients who were hemodynamically unstable died, compared to 1 of 12 patients who died in those who presented hemodynamically stable. Overall survival was 75%. Conclusions Survival and complications of pediatric truncal vascular injury are related to hemodynamic status at the time of presentation. Associated injuries are higher with trauma involving the abdomen. PMID:19853755

  19. Vascular Hyperactivity in the Rat Renal Aorta Participates in the Association between Immune Complex-Mediated Glomerulonephritis and Systemic Hypertension.

    PubMed

    Pérez-Torres, Israel; Moguel-González, Bernardo; Soria-Castro, Elizabeth; Guarner-Lans, Verónica; Avila-Casado, María Del Carmen; Goes, Teresa Imelda Fortoul Vander

    2018-06-03

    Introduction : systemic hypertension (SH) involving endothelial dysfunction contributes to immune complex-mediated glomerulonephritis (ICGN). Objective, we demonstrate a relationship between ICGN and SH by analyzing vascular reactivity in renal aortic rings. Methods : 48 male Wistar rats were divided into four groups: (a) control (C); (b) injected with bovine serum albumin (BSA); (c) receiving 200 mg/L NAME (an analog of arginine that inhibits NO production) in drinking water; and (d) receiving BSA and 200 mg/L NAME. Rats were pre-immunized subcutaneously with BSA and Freund's adjuvant. After 10 days, groups (b) and (c) received 1 mg/mL of BSA in saline intravenous (IV) daily for 35 days. The urine of 24 h was measured at days 0, 15, 30 and 45. Results : vascular reactivity to norepinephrine (NE), acetylcholine (Ach) and NAME were tested. Creatinine clearance, vasodilatation, eNOS and elastic fibers were diminished ( p ≤ 0.001). Blood pressure, vasoconstriction, iNOS were increased, and glomerular alterations were observed in groups (b), (c) and (d) when compared to group (a) ( p ≤ 0.001). Conclusions: SH contributes to the development of progressive renal disease in ICGN. Alterations of the vascular reactivity are mediated by the endothelium in the renal aorta. Thus, the endothelium plays a determinant role in the production of vasoactive substances such as NO during this process.

  20. Open Problems in Computational Vascular Biomechanics: Hemodynamics and Arterial Wall Mechanics

    PubMed Central

    Taylor, C.A.; Humphrey, J.D.

    2009-01-01

    The vasculature consists of a complex network of vessels ranging from large arteries to arterioles, capillaries, venules, and veins. This network is vital for the supply of oxygen and nutrients to tissues and the removal of carbon dioxide and waste products from tissues. Because of its primary role as a pressure-driven chemomechanical transport system, it should not be surprising that mechanics plays a vital role in the development and maintenance of the normal vasculature as well as in the progression and treatment of vascular disease. This review highlights some past successes of vascular biomechanics, but emphasizes the need for research that synthesizes complementary advances in molecular biology, biomechanics, medical imaging, computational methods, and computing power for purposes of increasing our understanding of vascular physiology and pathophysiology as well as improving the design of medical devices and clinical interventions, including surgical procedures. That is, computational mechanics has great promise to contribute to the continued improvement of vascular health. PMID:20161129

  1. Vascular Cambium Development

    PubMed Central

    Nieminen, Kaisa; Blomster, Tiina; Helariutta, Ykä; Mähönen, Ari Pekka

    2015-01-01

    Secondary phloem and xylem tissues are produced through the activity of vascular cambium, the cylindrical secondary meristem which arises among the primary plant tissues. Most dicotyledonous species undergo secondary development, among them Arabidopsis. Despite its small size and herbaceous nature, Arabidopsis displays prominent secondary growth in several organs, including the root, hypocotyl and shoot. Together with the vast genetic resources and molecular research methods available for it, this has made Arabidopsis a versatile and accessible model organism for studying cambial development and wood formation. In this review, we discuss and compare the development and function of the vascular cambium in the Arabidopsis root, hypocotyl, and shoot. We describe the current understanding of the molecular regulation of vascular cambium and compare it to the function of primary meristems. We conclude with a look at the future prospects of cambium research, including opportunities provided by phenotyping and modelling approaches, complemented by studies of natural variation and comparative genetic studies in perennial and woody plant species. PMID:26078728

  2. Low vascularity predicts favourable outcomes in leiomyoma patients treated with uterine artery embolization.

    PubMed

    Tang, Yixin; Chen, Chunlin; Duan, Hui; Ma, Ben; Liu, Ping

    2016-10-01

    To investigate the clinical factors predicting outcomes of leiomyoma treated with uterine artery embolization (UAE). A total of 183 uterine leiomyoma patients undergoing UAE were retrospectively analyzed. Patient age, characteristics of vascular supply in magnetic resonance imaging (MRI)/digital subtraction angiography (DSA), number, size and location of leiomyoma were recorded. Leiomyoma regrowth, new leiomyoma appearance and recurrence of any previously reported symptoms were carefully monitored over a mean follow-up of 30 months (median 32 months, range 12-80). Potential recurrence risk factors were analyzed by univariate and multivariate cox regression analysis. Twenty-three recurrences were recorded. The difference in the vascularity classification systems between MRI and DSA was not statistically significant (P = 0.059). High vascularity in MRI, high vascularity in DSA and multiple leiomyoma showed a significant risk of recurrence using univariate and multivariate analysis (P = 0.004, P < 0.001 and P = 0.023, respectively). The other factors were not significantly associated with leiomyoma recurrence (P > 0.05). Low vascularity and solitary leiomyoma indicated favourable outcomes in patients treated with UAE. • Low vascularity and solitary mass predicted favourable outcomes in UAE-treated patients. • MRI might provide information on vascularity in leiomyoma before UAE. • Variations in vascular supply, age, size, location were not associated with recurrence.

  3. Endothelial and Smooth Muscle Cell Ion Channels in Pulmonary Vasoconstriction and Vascular Remodeling

    PubMed Central

    Makino, Ayako; Firth, Amy L.; Yuan, Jason X.-J.

    2017-01-01

    The pulmonary circulation is a low resistance and low pressure system. Sustained pulmonary vasoconstriction and excessive vascular remodeling often occur under pathophysiological conditions such as in patients with pulmonary hypertension. Pulmonary vasoconstriction is a consequence of smooth muscle contraction. Many factors released from the endothelium contribute to regulating pulmonary vascular tone, while the extracellular matrix in the adventitia is the major determinant of vascular wall compliance. Pulmonary vascular remodeling is characterized by adventitial and medial hypertrophy due to fibroblast and smooth muscle cell proliferation, neointimal proliferation, intimal, and plexiform lesions that obliterate the lumen, muscularization of precapillary arterioles, and in situ thrombosis. A rise in cytosolic free Ca2+ concentration ([Ca2+]cyt) in pulmonary artery smooth muscle cells (PASMC) is a major trigger for pulmonary vasoconstriction, while increased release of mitogenic factors, upregulation (or downregulation) of ion channels and transporters, and abnormalities in intracellular signaling cascades are key to the remodeling of the pulmonary vasculature. Changes in the expression, function, and regulation of ion channels in PASMC and pulmonary arterial endothelial cells play an important role in the regulation of vascular tone and development of vascular remodeling. This article will focus on describing the ion channels and transporters that are involved in the regulation of pulmonary vascular function and structure and illustrating the potential pathogenic role of ion channels and transporters in the development of pulmonary vascular disease. PMID:23733654

  4. Pathophysiological consequences of VEGF-induced vascular permeability

    NASA Astrophysics Data System (ADS)

    Weis, Sara M.; Cheresh, David A.

    2005-09-01

    Although vascular endothelial growth factor (VEGF) induces angiogenesis, it also disrupts vascular barrier function in diseased tissues. Accordingly, VEGF expression in cancer and ischaemic disease has unexpected pathophysiological consequences. By uncoupling endothelial cell-cell junctions VEGF causes vascular permeability and oedema, resulting in extensive injury to ischaemic tissues after stroke or myocardial infarction. In cancer, VEGF-mediated disruption of the vascular barrier may potentiate tumour cell extravasation, leading to widespread metastatic disease. Therefore, by blocking the vascular permeability promoting effects of VEGF it may be feasible to reduce tissue injury after ischaemic disease and minimize the invasive properties of circulating tumour cells.

  5. Systemic lupus erythematosus in a multiethnic US cohort (LUMINA L II): relationship between vascular events and the use of hormone replacement therapy in postmenopausal women.

    PubMed

    Fernández, Mónica; Calvo-Alén, Jaime; Bertoli, Ana M; Bastian, Holly M; Fessler, Barri J; McGwin, Gerald; Reveille, John D; Vilá, Luis M; Alarcón, Graciela S

    2007-10-01

    To examine the influence of hormone replacement therapy (HRT) in the occurrence of vascular arterial and venous thrombotic events in postmenopausal women with systemic lupus erythematosus (SLE). SLE women aged > or =16 years, disease duration < or =5 years from LUMINA, a multiethnic, longitudinal outcome study, were included. Menopause was defined at disease onset as the presence of amenorrhea >6 months and/or oophorectomy, and/or increased follicle stimulating hormone values, and/or HRT use regardless of the presence or absence of climacteric symptoms (hot flashes). Patients were divided into HRT ever users and nonusers. Patients with positive antiphospholipid antibodies (n = 9) or vascular arterial events (n = 1) occurring before HRT use were excluded. The occurrence of vascular arterial and venous thrombotic events was compared between HRT users and HRT nonusers and its role examined by logistic regression after adjusting for "confounding by indication" using propensity score or logistic regression analyses. Seventy-two postmenopausal women, 32 (44%) HRT users and 40 (56%) HRT nonusers, were studied. HRT use was associated with fewer vascular arterial but not venous thrombotic events (P = 0.021) in the univariable analyses. However, after adjusting for the propensity score, HRT use was no longer significant (P = 0.064). Comparable results were obtained by logistic regression. HRT use was not associated with the occurrence of vascular arterial events in the LUMINA patients. HRT use in women with SLE should be individualized, but our data suggest its use may be safe if antiphospholipid antibodies are not present or vascular arterial events have not previously occurred.

  6. Novel Paradigms for Dialysis Vascular Access: Downstream Vascular Biology–Is There a Final Common Pathway?

    PubMed Central

    2013-01-01

    Summary Vascular access dysfunction is a major cause of morbidity and mortality in hemodialysis patients. The most common cause of vascular access dysfunction is venous stenosis from neointimal hyperplasia within the perianastomotic region of an arteriovenous fistula and at the graft-vein anastomosis of an arteriovenous graft. There have been few, if any, effective treatments for vascular access dysfunction because of the limited understanding of the pathophysiology of venous neointimal hyperplasia formation. This review will (1) describe the histopathologic features of hemodialysis access stenosis; (2) discuss novel concepts in the pathogenesis of neointimal hyperplasia development, focusing on downstream vascular biology; (3) highlight future novel therapies for treating downstream biology; and (4) discuss future research areas to improve our understanding of downstream biology and neointimal hyperplasia development. PMID:23990166

  7. Urticarial Reactions: Vascular Erythema, Urticaria, Vasculitis

    PubMed Central

    Sibbald, R. Gary

    1987-01-01

    Vascular erythemas, including urticaria and vasculitis, represent diagnostic and therapeutic challenges. A careful systemic approach to history and physical examination should be followed by appropriate investigations to rule out systemic disease. Chronic urticaria patients should be physically tested to identify cholinergic, dermagraphic, and cold-induced responses. Food diaries and careful drug history may be important to identify exacerbating factors in chronic urticaria. A skin biopsy is necessary to diagnose vasculitis. Therapy of any underlying cause is supplemented with H1 antihistamines in urticaria patients, while vasculitis requires a different anti-inflammatory approach. PMID:21263956

  8. Molecular parallels between neural and vascular development.

    PubMed

    Eichmann, Anne; Thomas, Jean-Léon

    2013-01-01

    The human central nervous system (CNS) features a network of ~400 miles of blood vessels that receives >20% of the body's cardiac output and uses most of its blood glucose. Many human diseases, including stroke, retinopathy, and cancer, are associated with the biology of CNS blood vessels. These vessels originate from extrinsic cell populations, including endothelial cells and pericytes that colonize the CNS and interact with glia and neurons to establish the blood-brain barrier and control cerebrovascular exchanges. Neurovascular interactions also play important roles in adult neurogenic niches, which harbor a unique population of neural stem cells that are intimately associated with blood vessels. We here review the cellular and molecular mechanisms required to establish the CNS vascular network, with a special focus on neurovascular interactions and the functions of vascular endothelial growth factors.

  9. Principal component analysis of indocyanine green fluorescence dynamics for diagnosis of vascular diseases

    NASA Astrophysics Data System (ADS)

    Seo, Jihye; An, Yuri; Lee, Jungsul; Choi, Chulhee

    2015-03-01

    Indocyanine green (ICG), a near-infrared fluorophore, has been used in visualization of vascular structure and non-invasive diagnosis of vascular disease. Although many imaging techniques have been developed, there are still limitations in diagnosis of vascular diseases. We have recently developed a minimally invasive diagnostics system based on ICG fluorescence imaging for sensitive detection of vascular insufficiency. In this study, we used principal component analysis (PCA) to examine ICG spatiotemporal profile and to obtain pathophysiological information from ICG dynamics. Here we demonstrated that principal components of ICG dynamics in both feet showed significant differences between normal control and diabetic patients with vascula complications. We extracted the PCA time courses of the first three components and found distinct pattern in diabetic patient. We propose that PCA of ICG dynamics reveal better classification performance compared to fluorescence intensity analysis. We anticipate that specific feature of spatiotemporal ICG dynamics can be useful in diagnosis of various vascular diseases.

  10. Suitability of Exoseal Vascular Closure Device for Antegrade Femoral Artery Puncture Site Closure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schmelter, Christopher, E-mail: christopher.schmelter@klinikum-ingolstadt.de; Liebl, Andrea; Poullos, Nektarios

    Purpose. To assess the efficacy and safety of the Exoseal vascular closure device for antegrade puncture of the femoral artery. Methods. In a prospective study from February 2011 to January 2012, a total of 93 consecutive patients received a total of 100 interventional procedures via an antegrade puncture of the femoral artery. An Exoseal vascular closure device (6F) was used for closure in all cases. Puncture technique, duration of manual compression, and use of compression bandages were documented. All patients were monitored by vascular ultrasound and color-coded duplex sonography of their respective femoral artery puncture site within 12 to 36more » h after angiography to check for vascular complications. Results. In 100 antegrade interventional procedures, the Exoseal vascular closure device was applied successfully for closure of the femoral artery puncture site in 96 cases (96 of 100, 96.0 %). The vascular closure device could not be deployed in one case as a result of kinking of the vascular sheath introducer and in three cases because the bioabsorbable plug was not properly delivered to the extravascular space adjacent to the arterial puncture site, but instead fully removed with the delivery system (4.0 %). Twelve to 36 h after the procedure, vascular ultrasound revealed no complications at the femoral artery puncture site in 93 cases (93.0 %). Minor vascular complications were found in seven cases (7.0 %), with four cases (4.0 %) of pseudoaneurysm and three cases (3.0 %) of significant late bleeding, none of which required surgery. Conclusion. The Exoseal vascular closure device was safely used for antegrade puncture of the femoral artery, with a high rate of procedural success (96.0 %), a low rate of minor vascular complications (7.0 %), and no major adverse events.« less

  11. S1P1 inhibits sprouting angiogenesis during vascular development.

    PubMed

    Ben Shoham, Adi; Malkinson, Guy; Krief, Sharon; Shwartz, Yulia; Ely, Yona; Ferrara, Napoleone; Yaniv, Karina; Zelzer, Elazar

    2012-10-01

    Coordination between the vascular system and forming organs is essential for proper embryonic development. The vasculature expands by sprouting angiogenesis, during which tip cells form filopodia that incorporate into capillary loops. Although several molecules, such as vascular endothelial growth factor A (Vegfa), are known to induce sprouting, the mechanism that terminates this process to ensure neovessel stability is still unknown. Sphingosine-1-phosphate receptor 1 (S1P(1)) has been shown to mediate interaction between endothelial and mural cells during vascular maturation. In vitro studies have identified S1P(1) as a pro-angiogenic factor. Here, we show that S1P(1) acts as an endothelial cell (EC)-autonomous negative regulator of sprouting angiogenesis during vascular development. Severe aberrations in vessel size and excessive sprouting found in limbs of S1P(1)-null mouse embryos before vessel maturation imply a previously unknown, mural cell-independent role for S1P(1) as an anti-angiogenic factor. A similar phenotype observed when S1P(1) expression was blocked specifically in ECs indicates that the effect of S1P(1) on sprouting is EC-autonomous. Comparable vascular abnormalities in S1p(1) knockdown zebrafish embryos suggest cross-species evolutionary conservation of this mechanism. Finally, genetic interaction between S1P(1) and Vegfa suggests that these factors interplay to regulate vascular development, as Vegfa promotes sprouting whereas S1P(1) inhibits it to prevent excessive sprouting and fusion of neovessels. More broadly, because S1P, the ligand of S1P(1), is blood-borne, our findings suggest a new mode of regulation of angiogenesis, whereby blood flow closes a negative feedback loop that inhibits sprouting angiogenesis once the vascular bed is established and functional.

  12. [Oral contraception and the vascular risk].

    PubMed

    Garnier, L F; Gruel, Y

    1989-01-01

    Vascular risk, mainly thromboembolitic risk, attributed to oral contraceptives (OCs) since 1962, has been primarily linked to ethinyl estradiol (EE). OCs which combine estrogen and have been associated with cerebral vascular accidents. A 1977 study showed a 40% increase of mortality due to cardiovascular complications in women taking OCs. There were of both an arterial and a venous character. The risk of myocardial infarction was 3 times more frequent among OC users. Deep venous thrombosis and pulmonary embolism were more numerous. Some other risk factors include smoking, hypertension, diabetes, and age 35. The risk of heart attack vanishes a few years after stopping OC use. The reduction of EE (and similarly progesterone) dosage from 100-50 mcg also lower the risk of hypertension, cerebral vascular accidents, and venous thrombosis. Prolonged use of OCs causes disorders of hemostasis affecting the walls of blood vessels, modifying the viscosity of blood flow (increase of hematocrits, reduction of venous tonus), modifying plasmatic coagulation (increase of platelets, increase of factors VII and X and plasma fibrinogen, and decrease of antithrombin III activity), and increased fibrinolysis. These anomalies are exclusively associated with high doses of estrogens. 5% of women using OCs develop moderate hypertension of 5-10 mm Hg of systolic pressure 5 years later, but after cessation it is reversed. OCs stimulate the renin-angiotensin-aldosterone system causing accelerated production of angiotensin II with the resultant forceful vasotension. 3 months after quitting OC use, high blood pressure returns to normal. EE can provoke diabetes; it increases very low density lipoprotein (VLDL) and high density lipoprotein (HDL) production, but total cholesterol is hardly affected. The androgenic property of progestogens reduces HDL. Combined OCs are contraindicated for women with hypertension, hyperlipidemia, diabetes, and a family history of vascular accidents.

  13. Vascular Diseases

    MedlinePlus

    ... vessels, such as diabetes or high cholesterol Smoking Obesity Losing weight, eating healthy foods, being active and not smoking can help vascular disease. Other treatments include medicines and surgery.

  14. Mechanistic insights into the vascular effects of blueberries: Evidence from recent studies.

    PubMed

    Cutler, Brett Ronald; Petersen, Chrissa; Anandh Babu, Pon Velayutham

    2017-06-01

    Cardiovascular disease is the leading cause of death in the United States. Dietary habits influence a variety of cardiovascular complications such as peripheral artery disease, heart failure, and kidney disease. We along with others have previously reported the cardiovascular beneficial effects of dietary flavonoids. Anthocyanins, one class of flavonoids widely available in berries, have recently drawn wide scientific attention because of their diverse health benefits. Epidemiological, clinical, and animal studies indicate that blueberry anthocyanins exert protection against cardiovascular complications by acting on multiple targets in the vascular system. These include activating endothelial nitric oxide synthase signaling, reducing oxidative stress, improving inflammatory pathways, and ameliorating dyslipidemia. Anthocyanins are extensively metabolized in humans suggesting that their vascular benefits are likely mediated by their circulating metabolites. However, the bioactivities of blueberry metabolites are unknown. Evaluating the bioactivities of metabolites, analyzing their structure-activity relationship, and well-designed human trials are needed to understand the potential vascular effects of blueberries and their metabolites. Understanding the vascular effects will provide a solid scientific foundation to recommend blueberries to improve vascular health. This review highlights the recent developments in the understanding of the vascular effects of blueberries with special emphasis on the molecular mechanisms involved. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. The use of Intravenous Laser Blood Irradiation (ILBI) at 630–640 nm to prevent vascular diseases and to increase life expectancy

    PubMed Central

    2015-01-01

    Background and Aims: The mortality rate from vascular diseases is one of the highest. The use of Intravenous Laser Blood Irradiation (ILBI) within the last 30 years has demonstrated high efficacy in the treatment of vascular, cardiac and other systemic diseases. Rationale: Laser energy at 630-640 nanometers is arguably the most effective for irradiation of blood and the vascular wall. Photons at this wavelength are absorbed by oxygen, improve microcirculation, can change the viscosity of the blood and affect vascular endothelium. Conclusions: In summary, more than 25 years of experience of using laser energy at 630-640 nm has shown that this waveband directly influences the parameters of all cells in the blood, blood plasma, the coagulation process and all the structural components of the vascular wall. Additionally, ILBI directly or indirectly affects the cells of the immune system, hormones, and exchange processes in an organism, thereby not only improving the function of the vascular system, but also the other systems of an organism. It can finally lead to lower the incidence and number of vascular diseases, and indirectly to the reduction of the number of diseases in other organs and even systemically, thus helping to prolong the lifespan. PMID:25941421

  16. Device and method for treatment of openings in vascular and septal walls

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Singhal, Pooja; Wilson, Thomas S.; Cosgriff-Hernandez, Elizabeth

    A device, system and method for treatment of an opening in vascular and/or septal walls including patent foramen ovale. The device has wings/stops on either end, an axis core covered in a shape memory foam and is deliverable via a catheter to the affected opening, finally expanding into a vascular or septal opening where it is held in place by the expandable shape memory stops or wings.

  17. The effect of interstitial pressure on therapeutic agent transport: coupling with the tumor blood and lymphatic vascular systems.

    PubMed

    Wu, Min; Frieboes, Hermann B; Chaplain, Mark A J; McDougall, Steven R; Cristini, Vittorio; Lowengrub, John S

    2014-08-21

    Vascularized tumor growth is characterized by both abnormal interstitial fluid flow and the associated interstitial fluid pressure (IFP). Here, we study the effect that these conditions have on the transport of therapeutic agents during chemotherapy. We apply our recently developed vascular tumor growth model which couples a continuous growth component with a discrete angiogenesis model to show that hypertensive IFP is a physical barrier that may hinder vascular extravasation of agents through transvascular fluid flux convection, which drives the agents away from the tumor. This result is consistent with previous work using simpler models without blood flow or lymphatic drainage. We consider the vascular/interstitial/lymphatic fluid dynamics to show that tumors with larger lymphatic resistance increase the agent concentration more rapidly while also experiencing faster washout. In contrast, tumors with smaller lymphatic resistance accumulate less agents but are able to retain them for a longer time. The agent availability (area-under-the curve, or AUC) increases for less permeable agents as lymphatic resistance increases, and correspondingly decreases for more permeable agents. We also investigate the effect of vascular pathologies on agent transport. We show that elevated vascular hydraulic conductivity contributes to the highest AUC when the agent is less permeable, but to lower AUC when the agent is more permeable. We find that elevated interstitial hydraulic conductivity contributes to low AUC in general regardless of the transvascular agent transport capability. We also couple the agent transport with the tumor dynamics to simulate chemotherapy with the same vascularized tumor under different vascular pathologies. We show that tumors with an elevated interstitial hydraulic conductivity alone require the strongest dosage to shrink. We further show that tumors with elevated vascular hydraulic conductivity are more hypoxic during therapy and that the response

  18. Vascular Morphogenesis in the Context of Inflammation: Self-Organization in a Fibrin-Based 3D Culture System.

    PubMed

    Rüger, Beate M; Buchacher, Tanja; Giurea, Alexander; Kubista, Bernd; Fischer, Michael B; Breuss, Johannes M

    2018-01-01

    Introduction: New vessel formation requires a continuous and tightly regulated interplay between endothelial cells with cells of the perivascular microenvironment supported by mechanic-physical and chemical cues from the extracellular matrix. Aim: Here we investigated the potential of small fragments of synovial tissue to form de novo vascular structures in the context of inflammation within three dimensional (3D) fibrin-based matrices in vitro , and assessed the contribution of mesenchymal stromal cell (MSC)-immune cell cross-talk to neovascularization considering paracrine signals in a fibrin-based co-culture model. Material and Methods: Synovial tissue fragments from patients with rheumatoid arthritis (RA) and inflammatory osteoarthritis (OA) were cultivated within 3D fibrin matrices for up to 4 weeks. Cellular and structural re-arrangement of the initially acellular matrix were documented by phase contrast microscopy and characterized by confocal laser-scanning microscopy of topographically intact 3D cultures and by immunohistochemistry. MSC-peripheral blood mononuclear cell (PBMC) co-cultures in the 3D fibrin system specifically addressed the influence of perivascular cell interactions to neo-vessel formation in a pro-inflammatory microenvironment. Cytokine levels in the supernatants of cultured explant tissues and co-cultures were evaluated by the Bio-Plex cytokine assay and ELISA. Results: Vascular outgrowth from the embedded tissue into the fibrin matrix was preceded by leukocyte egress from the tissue fragments. Neo-vessels originating from both the embedded sample and from clusters locally formed by emigrated mononuclear cells were consistently associated with CD45 + leukocytes. MSC and PBMC in co-culture formed vasculogenic clusters. Clusters and cells with endothelial phenotype emerging from them, were surrounded by a collagen IV scaffold. No vascular structures were observed in control 3D monocultures of PBMC or MSC. Paracrine signals released by

  19. Accreditation status and geographic location of outpatient vascular testing facilities among Medicare beneficiaries: the VALUE (Vascular Accreditation, Location & Utilization Evaluation) study.

    PubMed

    Rundek, Tatjana; Brown, Scott C; Wang, Kefeng; Dong, Chuanhui; Farrell, Mary Beth; Heller, Gary V; Gornik, Heather L; Hutchisson, Marge; Needleman, Laurence; Benenati, James F; Jaff, Michael R; Meier, George H; Perese, Susana; Bendick, Phillip; Hamburg, Naomi M; Lohr, Joann M; LaPerna, Lucy; Leers, Steven A; Lilly, Michael P; Tegeler, Charles; Alexandrov, Andrei V; Katanick, Sandra L

    2014-10-01

    There is limited information on the accreditation status and geographic distribution of vascular testing facilities in the US. The Centers for Medicare & Medicaid Services (CMS) provide reimbursement to facilities regardless of accreditation status. The aims were to: (1) identify the proportion of Intersocietal Accreditation Commission (IAC) accredited vascular testing facilities in a 5% random national sample of Medicare beneficiaries receiving outpatient vascular testing services; (2) describe the geographic distribution of these facilities. The VALUE (Vascular Accreditation, Location & Utilization Evaluation) Study examines the proportion of IAC accredited facilities providing vascular testing procedures nationally, and the geographic distribution and utilization of these facilities. The data set containing all facilities that billed Medicare for outpatient vascular testing services in 2011 (5% CMS Outpatient Limited Data Set (LDS) file) was examined, and locations of outpatient vascular testing facilities were obtained from the 2011 CMS/Medicare Provider of Services (POS) file. Of 13,462 total vascular testing facilities billing Medicare for vascular testing procedures in a 5% random Outpatient LDS for the US in 2011, 13% (n=1730) of facilities were IAC accredited. The percentage of IAC accredited vascular testing facilities in the LDS file varied significantly by US region, p<0.0001: 26%, 12%, 11%, and 7% for the Northeast, South, Midwest, and Western regions, respectively. Findings suggest that the proportion of outpatient vascular testing facilities that are IAC accredited is low and varies by region. Increasing the number of accredited vascular testing facilities to improve test quality is a hypothesis that should be tested in future research. © The Author(s) 2014.

  20. Partial contribution of the Keap1–Nrf2 system to cadmium-mediated metallothionein expression in vascular endothelial cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shinkai, Yasuhiro; Kimura, Tomoki; Itagaki, Ayaka

    Cadmium is an environmental electrophile that modifies protein reactive thiols such as Kelch-like ECH-associated protein 1 (Keap1), a negative regulator of nuclear factor-erythroid 2-related factor 2 (Nrf2). In the present study, we investigated a role of the Keap1–Nrf2 system in cellular response to cadmium in vascular endothelial cells. Exposure of bovine aortic endothelial cells to cadmium resulted in modification of Keap1 and Nrf2 activation, thereby up-regulating not only its typical downstream proteins but also metallothionein-1/2. Experiments with siRNA-mediated knockdown of Nrf2 or Keap1 supported participation of the Keap1–Nrf2 system in the modulation of metallothionein-1/2 expression. Furthermore, chromatin immunoprecipitation assay showedmore » that Nrf2 was recruited to the antioxidant response element of the promoter region of the bovine metallothionein-2 gene in the presence of cadmium. These results suggest that the transcription factor Nrf2 plays, at least in part, a role in the changes in metallothionein expression mediated by exposure to cadmium. - Highlights: • Role of the Keap1–Nrf2 system in cellular response to cadmium was examined. • We used bovine aortic endothelial cells as a model of the vascular endothelium. • Exposure of cells to cadmium resulted in modification of Keap1 and Nrf2 activation. • Keap1–Nrf2 system participated in the modulation of metallothionein-1/2 expression. • Nrf2 was recruited to the antioxidant response element of MT2 promoter region.« less

  1. Strategies for the Segmentation of Subcutaneous Vascular Patterns in Thermographic Images

    NASA Astrophysics Data System (ADS)

    Chan, Eric K. Y.; Pearce, John A.

    1989-05-01

    Computer-assisted segmentation of vascular patterns in thermographic images provides the clinician with graphic outlines of thermally significant subcutaneous blood vessels. Segmentation strategies compared here consist of image smoothing protocols followed by thresholding and zero-crossing edge detectors. Median prefiltering followed by the Frei-Chen algorithm gave the most reproducible results, with an execution time of 143 seconds for 256 X 256 images. The Laplacian of Gaussian operator was not suitable due to streak artifacts in the thermographic imaging system. This computerized process may be adopted in a fast paced clinical environment to aid in the diagnosis and assessment of peripheral circulatory diseases, Raynaud's Disease3, phlebitis, varicose veins, as well as diseases of the autonomic nervous system. The same methodology may be applied to enhance the appearance of abnormal breast vascular patterns, and hence serve as an adjunct to mammography in the diagnosis of breast cancer. The automatically segmented vascular patterns, which have a hand drawn appearance, may also be used as a data reduction precursor to higher level pattern analysis and classification tasks.

  2. Systemic lupus erythematosus in a multiethnic US cohort (LUMINA): XXI. Disease activity, damage accrual, and vascular events in pre- and postmenopausal women.

    PubMed

    Fernández, Mónica; Calvo-Alén, Jaime; Alarcón, Graciela S; Roseman, Jeffrey M; Bastian, Holly M; Fessler, Barri J; McGwin, Gerald; Vilá, Luis M; Sanchez, Martha L; Reveille, John D

    2005-06-01

    To determine the differences in clinical manifestations, disease activity, damage accrual, and medication use in systemic lupus erythematosus (SLE) patients as a function of menopausal status at disease onset. Women with SLE as per the criteria of the American College of Rheumatology, with disease duration of 6 months, and/or oophorectomy, and/or increased follicle-stimulating hormone values for reproductive-age women, and/or treatment with hormone replacement therapy. Patients were divided into premenopausal and postmenopausal categories. Socioeconomic status, cumulative clinical manifestations, disease activity (at study entry or time 0, last visit, and over time), as measured by the Systemic Lupus Activity Measure, and damage accrual, as measured by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index (at time 0 and at last visit) were compared between the 2 groups of women. Multivariable models were then examined making adjustments for all possible known confounders. Dependent variables in the models were renal involvement, damage accrual, arterial vascular events, and venous thrombosis. Five hundred eighteen women from the LUMINA cohort were included; 436 (84.2%) were premenopausal and 82 (15.8%) were postmenopausal. Disease onset after menopause was more common among Caucasians. Renal involvement was more common in premenopausal women, whereas vascular arterial events were more frequent in postmenopausal women. All other disease manifestations, as well as disease activity, were comparable between both groups. The presence of damage accrual at time 0 and study end was more frequent in

  3. Vascular gene expression: a hypothesis

    PubMed Central

    Martínez-Navarro, Angélica C.; Galván-Gordillo, Santiago V.; Xoconostle-Cázares, Beatriz; Ruiz-Medrano, Roberto

    2013-01-01

    The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular tissues. This tissue-specific expression in Arabidopsis is predicted by the overrepresentation of GA/CT-rich motifs in gene promoters. In this work we have searched for common motifs in upstream regions of the homologous genes from plants considered to possess a “primitive” vascular tissue (a lycophyte), as well as from others that lack a true vascular tissue (a bryophyte), and finally from chlorophytes. Both lycophyte and bryophyte display motifs similar to those found in Arabidopsis with a significantly low E-value, while the chlorophytes showed either a different conserved motif or no conserved motif at all. These results suggest that these same genes are expressed coordinately in non-vascular plants; this coordinate expression may have been one of the prerequisites for the development of conducting tissues in plants. We have also analyzed the phylogeny of conserved proteins that may be involved in phloem function and development. The presence of CmPP16, APL, FT, and YDA in chlorophytes suggests the recruitment of ancient regulatory networks for the development of the vascular tissue during evolution while OPS is a novel protein specific to vascular plants. PMID:23882276

  4. Inter-arm systolic blood pressure differences, relations with future vascular events and mortality in patients with and without manifest vascular disease.

    PubMed

    Kranenburg, Guido; Spiering, Wilko; de Jong, Pim A; Kappelle, L Jaap; de Borst, Gert Jan; Cramer, Maarten J; Visseren, Frank L J; Aboyans, Victor; Westerink, Jan

    2017-10-01

    Inter-arm systolic blood pressure difference (SBPD) is an easily obtained patient characteristic which relates to vascular disease. We aimed to identify determinants of large inter-arm SBPD and to investigate the relation between inter-arm SBPD and vascular events in patients with and without manifest vascular disease. In a cohort of 7344 patients with manifest vascular disease or vascular risk factors alone enrolled in the Second Manifestations of ARTerial disease (SMART) study, single bilateral non-simultaneous blood pressure measurements were performed. Logistic and Cox regression was used to identify determinants of large inter-arm SBPD (≥15mmHg) and to investigate the relation between inter-arm SBPD and vascular events (composite of non-fatal myocardial infarction, stroke, and vascular mortality) and all-cause mortality. In all patients the median inter-arm SBPD was 7mmHg (IQR 3-11) and 1182 (16%) patients had inter-arm SBPD ≥15mmHg. Higher age, higher systolic blood pressure, diabetes mellitus, peripheral artery disease, carotid artery stenosis, higher carotid intima-media thickness, and lower ankle-brachial indices were related to large inter-arm SBPD (≥15mmHg). Each 5mmHg increase in inter-arm SBPD was related to a 12% higher risk of vascular events in patients without manifest vascular disease (HR 1.12; 95% CI 1.00-1.27), whereas no relation was apparent in patients with manifest vascular disease (HR 0.98; 95% CI 0.93-1.04, interaction p-value 0.036). Inter-arm SBPD was not related to all-cause mortality (HR 1.05; 95% CI 0.93-1.19). Inter-arm SBPD relates to a higher risk of vascular events in patients without manifest vascular disease, whereas this relation is not apparent in patients with manifest vascular disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. VESGEN Software for Mapping and Quantification of Vascular Regulators

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia A.; Vickerman, Mary B.; Keith, Patricia A.

    2012-01-01

    VESsel GENeration (VESGEN) Analysis is an automated software that maps and quantifies effects of vascular regulators on vascular morphology by analyzing important vessel parameters. Quantification parameters include vessel diameter, length, branch points, density, and fractal dimension. For vascular trees, measurements are reported as dependent functions of vessel branching generation. VESGEN maps and quantifies vascular morphological events according to fractal-based vascular branching generation. It also relies on careful imaging of branching and networked vascular form. It was developed as a plug-in for ImageJ (National Institutes of Health, USA). VESGEN uses image-processing concepts of 8-neighbor pixel connectivity, skeleton, and distance map to analyze 2D, black-and-white (binary) images of vascular trees, networks, and tree-network composites. VESGEN maps typically 5 to 12 (or more) generations of vascular branching, starting from a single parent vessel. These generations are tracked and measured for critical vascular parameters that include vessel diameter, length, density and number, and tortuosity per branching generation. The effects of vascular therapeutics and regulators on vascular morphology and branching tested in human clinical or laboratory animal experimental studies are quantified by comparing vascular parameters with control groups. VESGEN provides a user interface to both guide and allow control over the users vascular analysis process. An option is provided to select a morphological tissue type of vascular trees, network or tree-network composites, which determines the general collections of algorithms, intermediate images, and output images and measurements that will be produced.

  6. Covariance of lichen and vascular plant floras

    USGS Publications Warehouse

    Bennett, J.P.; Wetmore, C.M.

    1999-01-01

    The geographic relationships among taxonomic groups are important to study to determine patterns of biodiversity and whether or not associations occur between large groups, e.g., birds and vascular plants. This study was undertaken to determine relationships between higher plants and lower plants, specifically vascular plant and lichen floras in nine national parks of the Great Lakes region. No significant relationship was found between vascular plant floras and lichen floras in this area, which spans 1200 km longitudinally, or between an additional 19 areas from North America that were less than 1000 km(2) in area. For areas larger than 1000 km(2), however, a significant positive relationship existed for 33 areas that span one to approximately 150 million km(2). The ratio of numbers of vascular plants to lichens appeared to average just over 6 across the 33 areas. In the Great Lakes parks, between 28-30% of either the vascular plant or lichen species were singletons (occurring in only one park), but the parks that contained the most singletons were not congruent: Isle Royale had the most singleton lichens, while Indiana Dunes had the most vascular plant singletons. Fewer lichen species (2%) than vascular plants (4%) occurred in all nine parks. Latitude appeared to explain some of the variation between the two groups: vascular plants decreased with increasing latitude, while lichens increased.

  7. ETS transcription factor ETV2/ER71/Etsrp in hematopoietic and vascular development, injury, and regeneration.

    PubMed

    Zhao, Haiyong; Xu, Canxin; Lee, Tae-Jin; Liu, Fang; Choi, Kyunghee

    2017-04-01

    The major goal in regenerative medicine is to repair and restore injured, diseased or aged tissue function, thereby promoting general health. As such, the field of regenerative medicine has great translational potential in undertaking many of the health concerns and needs that we currently face. In particular, hematopoietic and vascular systems supply oxygen and nutrients and thus play critical roles in tissue development and tissue regeneration. Additionally, tissue vasculature serves as a tissue stem cell niche and thus contributes to tissue homeostasis. Notably, hematopoietic and vascular systems are sensitive to injury and subject to regeneration. As such, successful hematopoietic and vascular regeneration is prerequisite for efficient tissue repair and organismal survival and health. Recent studies have established that the interplay among the ETS transcription factor ETV2, vascular endothelial growth factor, and its receptor VEGFR2/FLK1 is essential for hematopoietic and vascular development. Emerging studies also support the role of these three factors and possible interplay in hematopoietic and vascular regeneration. Comprehensive understanding of the molecular mechanisms involved in the regulation and function of these three factors may lead to more effective approaches in promoting tissue repair and regeneration. Developmental Dynamics 246:318-327, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Non-contact continuous-wave diffuse optical tomographic system to capture vascular dynamics in the foot

    NASA Astrophysics Data System (ADS)

    Hoi, Jennifer W.; Kim, Hyun K.; Khalil, Michael A.; Fong, Christopher J.; Marone, Alessandro; Shrikhande, Gautam; Hielscher, Andreas H.

    2015-03-01

    Dynamic optical tomographic imaging has shown promise in diagnosing and monitoring peripheral arterial disease (PAD), which affects 8 to 12 million in the United States. PAD is the narrowing of the arteries that supply blood to the lower extremities. Prolonged reduced blood flow to the foot leads to ulcers and gangrene, which makes placement of optical fibers for contact-based optical tomography systems difficult and cumbersome. Since many diabetic PAD patients have foot wounds, a non-contact interface is highly desirable. We present a novel non-contact dynamic continuous-wave optical tomographic imaging system that images the vasculature in the foot for evaluating PAD. The system images at up to 1Hz by delivering 2 wavelengths of light to the top of the foot at up to 20 source positions through collimated source fibers. Transmitted light is collected with an electron multiplying charge couple device (EMCCD) camera. We demonstrate that the system can resolve absorbers at various locations in a phantom study and show the system's first clinical 3D images of total hemoglobin changes in the foot during venous occlusion at the thigh. Our initial results indicate that this system is effective in capturing the vascular dynamics within the foot and can be used to diagnose and monitor treatment of PAD in diabetic patients.

  9. Molecular Parallels between Neural and Vascular Development

    PubMed Central

    Eichmann, Anne; Thomas, Jean-Léon

    2013-01-01

    The human central nervous system (CNS) features a network of ∼400 miles of blood vessels that receives >20% of the body’s cardiac output and uses most of its blood glucose. Many human diseases, including stroke, retinopathy, and cancer, are associated with the biology of CNS blood vessels. These vessels originate from extrinsic cell populations, including endothelial cells and pericytes that colonize the CNS and interact with glia and neurons to establish the blood–brain barrier and control cerebrovascular exchanges. Neurovascular interactions also play important roles in adult neurogenic niches, which harbor a unique population of neural stem cells that are intimately associated with blood vessels. We here review the cellular and molecular mechanisms required to establish the CNS vascular network, with a special focus on neurovascular interactions and the functions of vascular endothelial growth factors. PMID:23024177

  10. Overview of the 2016 U.S. Food and Drug Administration Circulatory System Devices Advisory Panel Meeting on the Absorb Bioresorbable Vascular Scaffold System.

    PubMed

    Steinvil, Arie; Rogers, Toby; Torguson, Rebecca; Waksman, Ron

    2016-09-12

    This study aims to describe the discussions and recommendations made during the U.S. Food and Drug Administration (FDA) Circulatory System Device Panel pre-market approval application for the Absorb Bioresorbable Vascular Scaffold (BVS) System. The Absorb BVS System is a first-of-its-kind fully bioresorbable percutaneous coronary intervention technology. The absorb BVS was studied in the ABSORB III (A Clinical Evaluation of Absorb BVS, the Everolimus Eluting Bioresorbable Vascular Scaffold in the Treatment of Subjects with de Novo Native Coronary Artery Lesions) trial, the pivotal U.S. investigational device exemption trial. Observational report of the FDA Circulatory System Device Panel pre-market approval application meeting held on March 15, 2016. The U.S. FDA Circulatory System Device Panel members reviewed the ABSROB III trial outcomes and additional post hoc analyses presented by the sponsor and the FDA. The ABSORB III trial met the primary endpoint of noninferiority of Absorb BVS compared with the control, XIENCE drug-eluting stent, for target lesion failure at 1 year. Although a higher numerical trend for adverse outcomes was reported for the Absorb BVS, there were no statistical differences between Absorb BVS and XIENCE for any safety or effectiveness components for target lesion failure or for the secondary pre-specified outcomes. Panel members raised concerns with regard to the ABSORB III results and post hoc analyses focusing mainly on the noninferiority design of the trial, the apparent safety issues of the Absorb BVS in small vessels, the mismatch of visually versus intravascular imaging assessed vessel size found in ABSORB III and its implications on the adequate device labeling, the safety of Absorb BVS in specific patient and lesion subsets, and the post-approval commitments of the sponsor. Following panel discussions and the evidence presented, the panel voted for approval of the device. Copyright © 2016 American College of Cardiology Foundation

  11. Theories of schizophrenia: a genetic-inflammatory-vascular synthesis

    PubMed Central

    Hanson, Daniel R; Gottesman, Irving I

    2005-01-01

    Background Schizophrenia, a relatively common psychiatric syndrome, affects virtually all brain functions yet has eluded explanation for more than 100 years. Whether by developmental and/or degenerative processes, abnormalities of neurons and their synaptic connections have been the recent focus of attention. However, our inability to fathom the pathophysiology of schizophrenia forces us to challenge our theoretical models and beliefs. A search for a more satisfying model to explain aspects of schizophrenia uncovers clues pointing to genetically mediated CNS microvascular inflammatory disease. Discussion A vascular component to a theory of schizophrenia posits that the physiologic abnormalities leading to illness involve disruption of the exquisitely precise regulation of the delivery of energy and oxygen required for normal brain function. The theory further proposes that abnormalities of CNS metabolism arise because genetically modulated inflammatory reactions damage the microvascular system of the brain in reaction to environmental agents, including infections, hypoxia, and physical trauma. Damage may accumulate with repeated exposure to triggering agents resulting in exacerbation and deterioration, or healing with their removal. There are clear examples of genetic polymorphisms in inflammatory regulators leading to exaggerated inflammatory responses. There is also ample evidence that inflammatory vascular disease of the brain can lead to psychosis, often waxing and waning, and exhibiting a fluctuating course, as seen in schizophrenia. Disturbances of CNS blood flow have repeatedly been observed in people with schizophrenia using old and new technologies. To account for the myriad of behavioral and other curious findings in schizophrenia such as minor physical anomalies, or reported decreased rates of rheumatoid arthritis and highly visible nail fold capillaries, we would have to evoke a process that is systemic such as the vascular and immune

  12. 3D bioprinting for vascularized tissue fabrication

    PubMed Central

    Richards, Dylan; Jia, Jia; Yost, Michael; Markwald, Roger; Mei, Ying

    2016-01-01

    3D bioprinting holds remarkable promise for rapid fabrication of 3D tissue engineering constructs. Given its scalability, reproducibility, and precise multi-dimensional control that traditional fabrication methods do not provide, 3D bioprinting provides a powerful means to address one of the major challenges in tissue engineering: vascularization. Moderate success of current tissue engineering strategies have been attributed to the current inability to fabricate thick tissue engineering constructs that contain endogenous, engineered vasculature or nutrient channels that can integrate with the host tissue. Successful fabrication of a vascularized tissue construct requires synergy between high throughput, high-resolution bioprinting of larger perfusable channels and instructive bioink that promotes angiogenic sprouting and neovascularization. This review aims to cover the recent progress in the field of 3D bioprinting of vascularized tissues. It will cover the methods of bioprinting vascularized constructs, bioink for vascularization, and perspectives on recent innovations in 3D printing and biomaterials for the next generation of 3D bioprinting for vascularized tissue fabrication. PMID:27230253

  13. Evidence for altered placental blood flow and vascularity in compromised pregnancies

    PubMed Central

    Reynolds, Lawrence P; Caton, Joel S; Redmer, Dale A; Grazul-Bilska, Anna T; Vonnahme, Kimberly A; Borowicz, Pawel P; Luther, Justin S; Wallace, Jacqueline M; Wu, Guoyao; Spencer, Thomas E

    2006-01-01

    The placenta is the organ that transports nutrients, respiratory gases, and wastes between the maternal and fetal systems. Consequently, placental blood flow and vascular development are essential components of normal placental function and are critical to fetal growth and development. Normal fetal growth and development are important to ensure optimum health of offspring throughout their subsequent life course. In numerous sheep models of compromised pregnancy, in which fetal or placental growth, or both, are impaired, utero-placental blood flows are reduced. In the models that have been evaluated, placental vascular development also is altered. Recent studies found that treatments designed to increase placental blood flow can ‘rescue’ fetal growth that was reduced due to low maternal dietary intake. Placental blood flow and vascular development are thus potential therapeutic targets in compromised pregnancies. PMID:16469783

  14. Building vascular networks.

    PubMed

    Bae, Hojae; Puranik, Amey S; Gauvin, Robert; Edalat, Faramarz; Carrillo-Conde, Brenda; Peppas, Nicholas A; Khademhosseini, Ali

    2012-11-14

    Only a few engineered tissues-skin, cartilage, bladder-have achieved clinical success, and biomaterials designed to replace more complex organs are still far from commercial availability. This gap exists in part because biomaterials lack a vascular network to transfer the oxygen and nutrients necessary for survival and integration after transplantation. Thus, generation of a functional vasculature is essential to the clinical success of engineered tissue constructs and remains a key challenge for regenerative medicine. In this Perspective, we discuss recent advances in vascularization of biomaterials through the use of biochemical modification, exogenous cells, or microengineering technology.

  15. Building Vascular Networks

    PubMed Central

    Bae, Hojae; Puranik, Amey S.; Gauvin, Robert; Edalat, Faramarz; Carrillo-Conde, Brenda; Peppas, Nicholas A.; Khademhosseini, Ali

    2013-01-01

    Only a few engineered tissues—skin, cartilage, bladder—have achieved clinical success, and biomaterials designed to replace more complex organs are still far from commercial availability. This gap exists in part because biomaterials lack a vascular network to transfer the oxygen and nutrients necessary for survival and integration after transplantation. Thus, generation of a functional vasculature is essential to the clinical success of engineered tissue constructs and remains a key challenge for regenerative medicine. In this Perspective, we discuss recent advances in vascularization of biomaterials through the use of biochemical modification, exogenous cells, or microengineering technology. PMID:23152325

  16. Photoacoustic discrimination of vascular and pigmented lesions using classical and Bayesian methods

    NASA Astrophysics Data System (ADS)

    Swearingen, Jennifer A.; Holan, Scott H.; Feldman, Mary M.; Viator, John A.

    2010-01-01

    Discrimination of pigmented and vascular lesions in skin can be difficult due to factors such as size, subungual location, and the nature of lesions containing both melanin and vascularity. Misdiagnosis may lead to precancerous or cancerous lesions not receiving proper medical care. To aid in the rapid and accurate diagnosis of such pathologies, we develop a photoacoustic system to determine the nature of skin lesions in vivo. By irradiating skin with two laser wavelengths, 422 and 530 nm, we induce photoacoustic responses, and the relative response at these two wavelengths indicates whether the lesion is pigmented or vascular. This response is due to the distinct absorption spectrum of melanin and hemoglobin. In particular, pigmented lesions have ratios of photoacoustic amplitudes of approximately 1.4 to 1 at the two wavelengths, while vascular lesions have ratios of about 4.0 to 1. Furthermore, we consider two statistical methods for conducting classification of lesions: standard multivariate analysis classification techniques and a Bayesian-model-based approach. We study 15 human subjects with eight vascular and seven pigmented lesions. Using the classical method, we achieve a perfect classification rate, while the Bayesian approach has an error rate of 20%.

  17. Engineering clinically relevant volumes of vascularized bone

    PubMed Central

    Roux, Brianna M; Cheng, Ming-Huei; Brey, Eric M

    2015-01-01

    Vascularization remains one of the most important challenges that must be overcome for tissue engineering to be consistently implemented for reconstruction of large volume bone defects. An extensive vascular network is needed for transport of nutrients, waste and progenitor cells required for remodelling and repair. A variety of tissue engineering strategies have been investigated in an attempt to vascularize tissues, including those applying cells, soluble factor delivery strategies, novel design and optimization of bio-active materials, vascular assembly pre-implantation and surgical techniques. However, many of these strategies face substantial barriers that must be overcome prior to their ultimate translation into clinical application. In this review recent progress in engineering vascularized bone will be presented with an emphasis on clinical feasibility. PMID:25877690

  18. Hedgehog and Resident Vascular Stem Cell Fate

    PubMed Central

    Mooney, Ciaran J.; Hakimjavadi, Roya; Fitzpatrick, Emma; Kennedy, Eimear; Walls, Dermot; Morrow, David; Redmond, Eileen M.; Cahill, Paul A.

    2015-01-01

    The Hedgehog pathway is a pivotal morphogenic driver during embryonic development and a key regulator of adult stem cell self-renewal. The discovery of resident multipotent vascular stem cells and adventitial progenitors within the vessel wall has transformed our understanding of the origin of medial and neointimal vascular smooth muscle cells (SMCs) during vessel repair in response to injury, lesion formation, and overall disease progression. This review highlights the importance of components of the Hh and Notch signalling pathways within the medial and adventitial regions of adult vessels, their recapitulation following vascular injury and disease progression, and their putative role in the maintenance and differentiation of resident vascular stem cells to vascular lineages from discrete niches within the vessel wall. PMID:26064136

  19. Hypoxic stress, brain vascular system, and β-amyloid: a primary cell culture study.

    PubMed

    Muche, Abebe; Bürger, Susanne; Arendt, Thomas; Schliebs, Reinhard

    2015-01-01

    This study stresses the hypothesis whether hypoxic events contribute to formation and deposition of β-amyloid (Aβ) in cerebral blood vessels by affecting the processing of endothelial amyloid precursor protein (APP). Therefore, cerebral endothelial cells (ECs) derived from transgenic Tg2576 mouse brain, were subjected to short periods of hypoxic stress, followed by assessment of formation and secretion of APP cleavage products sAPPα, sAPPβ, and Aβ as well as the expression of endothelial APP. Hypoxic stress of EC leads to enhanced secretion of sAPPβ into the culture medium as compared to normoxic controls, which is accompanied by increased APP expression, induction of vascular endothelial growth factor (VEGF) synthesis, nitric oxide production, and differential changes in endothelial p42/44 (ERK1/2) expression. The hypoxia-mediated up-regulation of p42/44 at a particular time of incubation was accompanied by a corresponding down-regulation of the phosphorylated form of p42/44. To reveal any role of hypoxia-induced VEGF in endothelial APP processing, ECs were exposed by VEGF. VEGF hardly affected the amount of sAPPβ and Aβ(1-40) secreted into the culture medium, whereas the suppression of the VEGF receptor action by SU-5416 resulted in decreased release of sAPPβ and Aβ(1-40) in comparison to control incubations, suggesting a role of VEGF in controlling the activity of γ-secretase, presumably via the VEGF receptor-associated tyrosine kinase. The data suggest that hypoxic stress represents a mayor risk factor in causing Aβ deposition in the brain vascular system by favoring the amyloidogenic route of endothelial APP processing. The hypoxic-stress-induced changes in β-secretase activity are presumably mediated by altering the phosphorylation status of p42/44, whereas the stress-induced up-regulation of VEGF appears to play a counteracting role by maintaining the balance of physiological APP processing.

  20. Mechanisms underlying caloric restriction and life span regulation: implications for vascular aging

    PubMed Central

    Ungvari, Zoltan; Parrado-Fernandez, Cristina; Csiszar, Anna; de Cabo, Rafael

    2008-01-01

    This review focuses on the emerging evidence that attenuation of the production of reactive oxygen species (ROS) and inhibition of inflammatory pathways play a central role in the anti-aging cardiovascular effects of caloric restriction (CR). Particular emphasis is placed on the potential role of the plasma membrane redox system in CR-induced pathways responsible for sensing oxidative stress and increasing cellular oxidative stress resistance. We propose that CR increases bioavailability of NO, decreases vascular ROS generation, activates the Nrf2/ARE pathway inducing ROS detoxification systems, exerts anti-inflammatory effects and, thereby, suppresses initiation/progression of vascular disease that accompany aging. PMID:18340017

  1. [Peripheral vascular injuries in polytrauma].

    PubMed

    Richter, A; Silbernik, D; Oestreich, K; Karaorman, M; Storz, L W

    1995-09-01

    Between 1972 und 1993 a total of 68 patients were treated at the Department of Surgery of the University Clinic of Mannheim for peripheral vascular injury resulting from multiple trauma. The average age of these patients was 31.3 years, and most of them were male (88.2%; n = 60). The injured vessels were localized evenly in all the extremities: 31 patients (45.5%) presented with arterial damage of the upper extremity, and 37 (54.5%) showed lesions along the femoro-popliteal arteries. The most frequent location of injured vessels in the multiply traumatized patient was the popliteal artery (n = 18, 26.5%), the distal part of the superficial femoral artery (n = 12, 17.6%), the brachial artery (n = 14, 20.6%) and the axillary artery (n = 10, 14.6%). The dominant cause, of trauma was road traffic accidents (72%), and 20 patients (29%) acquired their vascular injuries as motorcyclists. There were also 13 occupational accidents (19%) involving vascular injuries. In addition to a vascular trauma 34 patients (50%) had complicated fractures, and a further 34 patients (50%) had multiple fractures: 12 (17.6%) had head and brain damage, 5 (7.3%) had blunt abdominal trauma and 6 (8.8%) had blunt thoracic injury. The general amputation rate was 2.9% (n = 2). One patient died on the table of a torn off subclavian artery combined with multiple other injuries. Paresis of the plexus is a particular problem after vascular lesions of the upper extremity: in 22 patients (71%) paresis of the plexus persisted after successful vascular reconstruction (follow-up period between 3 months and 16 years, median time 3.45 years).(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Implantation of Vascular Grafts Lined with Genetically Modified Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Wilson, James M.; Birinyi, Louis K.; Salomon, Robert N.; Libby, Peter; Callow, Allan D.; Mulligan, Richard C.

    1989-06-01

    The possibility of using the vascular endothelial cell as a target for gene replacement therapy was explored. Recombinant retroviruses were used to transduce the lacZ gene into endothelial cells harvested from mongrel dogs. Prosthetic vascular grafts seeded with the genetically modified cells were implanted as carotid interposition grafts into the dogs from which the original cells were harvested. Analysis of the graft 5 weeks after implantation revealed genetically modified endothelial cells lining the luminal surface of the graft. This technology could be used in the treatment of atherosclerosis disease and the design of new drug delivery systems.

  3. VASCULAR ACTIONS OF ESTROGENS: FUNCTIONAL IMPLICATIONS

    PubMed Central

    Miller, Virginia M.; Duckles, Sue P.

    2009-01-01

    The impact of estrogen exposure in preventing or treating cardiovascular disease is controversial. But it is clear that estrogen has important effects on vascular physiology and pathophysiology, with potential therapeutic implications. Therefore, it is the goal of this review to summarize, using an integrated approach, current knowledge of the vascular effects of estrogen, both in humans and in experimental animals. Aspects of estrogen synthesis and receptors, as well as general mechanisms of estrogenic action are reviewed with an emphasis on issues particularly relevant to the vascular system. Recent understanding of the impact of estrogen on mitochondrial function suggests that the longer lifespan of women compared to men may depend in part on the ability of estrogen to decrease production of reactive oxygen species in mitochondria. Mechanisms by which estrogen increases endothelial vasodilator function, promotes angiogenesis and modulates autonomic function are summarized. Key aspects of the relevant pathophysiology of inflammation, atherosclerosis, stroke, migraine and thrombosis are reviewed concerning current knowledge of estrogenic effects. A number of emerging concepts are addressed throughout. These include the importance of estrogenic formulation and route of administration and the impact of genetic polymorphisms, either in estrogen receptors or in enzymes responsible for estrogen metabolism, on responsiveness to hormone treatment. The importance of local metabolism of estrogenic precursors and the impact of timing for initiation of treatment and its duration are also considered. While consensus opinions are emphasized, controversial views are presented in order to stimulate future research. PMID:18579753

  4. Systemic Hypoxia Changes the Organ-Specific Distribution of Vascular Endothelial Growth Factor and Its Receptors

    NASA Astrophysics Data System (ADS)

    Marti, Hugo H.; Risau, Werner

    1998-12-01

    Vascular endothelial growth factor (VEGF) plays a key role in physiological blood vessel formation and pathological angiogenesis such as tumor growth and ischemic diseases. Hypoxia is a potent inducer of VEGF in vitro. Here we demonstrate that VEGF is induced in vivo by exposing mice to systemic hypoxia. VEGF induction was highest in brain, but also occurred in kidney, testis, lung, heart, and liver. In situ hybridization analysis revealed that a distinct subset of cells within a given organ, such as glial cells and neurons in brain, tubular cells in kidney, and Sertoli cells in testis, responded to the hypoxic stimulus with an increase in VEGF expression. Surprisingly, however, other cells at sites of constitutive VEGF expression in normal adult tissues, such as epithelial cells in the choroid plexus and kidney glomeruli, decreased VEGF expression in response to the hypoxic stimulus. Furthermore, in addition to VEGF itself, expression of VEGF receptor-1 (VEGFR-1), but not VEGFR-2, was induced by hypoxia in endothelial cells of lung, heart, brain, kidney, and liver. VEGF itself was never found to be up-regulated in endothelial cells under hypoxic conditions, consistent with its paracrine action during normoxia. Our results show that the response to hypoxia in vivo is differentially regulated at the level of specific cell types or layers in certain organs. In these tissues, up- or down-regulation of VEGF and VEGFR-1 during hypoxia may influence their oxygenation after angiogenesis or modulate vascular permeability.

  5. Vascular depression consensus report - a critical update.

    PubMed

    Aizenstein, Howard J; Baskys, Andrius; Boldrini, Maura; Butters, Meryl A; Diniz, Breno S; Jaiswal, Manoj Kumar; Jellinger, Kurt A; Kruglov, Lev S; Meshandin, Ivan A; Mijajlovic, Milija D; Niklewski, Guenter; Pospos, Sarah; Raju, Keerthy; Richter, Kneginja; Steffens, David C; Taylor, Warren D; Tene, Oren

    2016-11-03

    Vascular depression is regarded as a subtype of late-life depression characterized by a distinct clinical presentation and an association with cerebrovascular damage. Although the term is commonly used in research settings, widely accepted diagnostic criteria are lacking and vascular depression is absent from formal psychiatric manuals such as the Diagnostic and Statistical Manual of Mental Disorders, 5 th edition - a fact that limits its use in clinical settings. Magnetic resonance imaging (MRI) techniques, showing a variety of cerebrovascular lesions, including extensive white matter hyperintensities, subcortical microvascular lesions, lacunes, and microinfarcts, in patients with late life depression, led to the introduction of the term "MRI-defined vascular depression". This diagnosis, based on clinical and MRI findings, suggests that vascular lesions lead to depression by disruption of frontal-subcortical-limbic networks involved in mood regulation. However, despite multiple MRI approaches to shed light on the spatiotemporal structural changes associated with late life depression, the causal relationship between brain changes, related lesions, and late life depression remains controversial. While postmortem studies of elderly persons who died from suicide revealed lacunes, small vessel, and Alzheimer-related pathologies, recent autopsy data challenged the role of these lesions in the pathogenesis of vascular depression. Current data propose that the vascular depression connotation should be reserved for depressed older patients with vascular pathology and evident cerebral involvement. Based on current knowledge, the correlations between intra vitam neuroimaging findings and their postmortem validity as well as the role of peripheral markers of vascular disease in late life depression are discussed. The multifold pathogenesis of vascular depression as a possible subtype of late life depression needs further elucidation. There is a need for correlative clinical

  6. Antenatal Hypoxia and Pulmonary Vascular Function and Remodeling

    PubMed Central

    Papamatheakis, Demosthenes G.; Blood, Arlin B.; Kim, Joon H.; Wilson, Sean M.

    2015-01-01

    This review provides evidence that antenatal hypoxia, which represents a significant and worldwide problem, causes prenatal programming of the lung. A general overview of lung development is provided along with some background regarding transcriptional and signaling systems of the lung. The review illustrates that antenatal hypoxic stress can induce a continuum of responses depending on the species examined. Fetuses and newborns of certain species and specific human populations are well acclimated to antenatal hypoxia. However, antenatal hypoxia causes pulmonary vascular disease in fetuses and newborns of most mammalian species and humans. Disease can range from mild pulmonary hypertension, to severe vascular remodeling and dangerous elevations in pressure. The timing, length, and magnitude of the intrauterine hypoxic stress are important to disease development, however there is also a genetic-environmental relationship that is not yet completely understood. Determining the origins of pulmonary vascular remodeling and pulmonary hypertension and their associated effects is a challenging task, but is necessary in order to develop targeted therapies for pulmonary hypertension in the newborn due to antenatal hypoxia that can both treat the symptoms and curtail or reverse disease progression. PMID:24063380

  7. Effects of Occupational Noise Exposure on 24-Hour Ambulatory Vascular Properties in Male Workers

    PubMed Central

    Chang, Ta-Yuan; Su, Ta-Chen; Lin, Shou-Yu; Jain, Ruei-Man; Chan, Chang-Chuan

    2007-01-01

    Background Epidemiologic studies have demonstrated that occupational noise exposure is associated with hypertension, but the related mechanism in vascular structural changes is unclear. Objective This panel study aimed to investigate effects of occupational noise exposure on ambulatory vascular structural properties in male workers. Methods We recruited 20 volunteers and divided them into a high-noise–exposure group of 15 and a low-noise–exposure group of 5 based on environmental noise measurement in an automobile manufacturing company. We determined individual noise exposure and measured personal ambulatory vascular property parameters simultaneously during 24 hr. Linear mixed-effects regression models were used to estimate transient and sustained effects of noise exposure on vascular parameters by adjusting some confounders collected from self-administrated questionnaires and health checkups. Results The high-noise–exposed (85 ± 8 dBA) workers had significantly higher systemic vascular resistance (SVR) than the low-noise–exposed workers (59 ± 4 dBA) during work and sleep periods. Contrarily, low-noise–exposed workers had significantly higher brachial artery compliance (BAC), brachial artery distensibility (BAD), and systemic vascular compliance (SVC; marginal, p = 0.07) than high-noise–exposed workers during off-duty periods. We also found that high-noise–exposed workers had significantly lower BAC (1.38 ± 0.55 %mL/mmHg) and BAD (1.29 ± 0.51 %/mmHg), as well as lower SVC (0.24 ± 0.10 mL/L/mmHg), but higher SVR (1.93 ± 0.67 mL/L/min) compared with low-noise–exposed workers over a 24-hr period. Conclusions Our findings suggest that in automobile workers, occupational noise exposure may have sustained, not transient, effects on vascular properties and also enhances the development of hypertension. PMID:18008000

  8. Peripheral vascular dysfunction in migraine: a review

    PubMed Central

    2013-01-01

    Numerous studies have indicated an increased risk of vascular disease among migraineurs. Alterations in endothelial and arterial function, which predispose to atherosclerosis and cardiovascular diseases, have been suggested as an important link between migraine and vascular disease. However, the available evidence is inconsistent. We aimed to review and summarize the published evidence about the peripheral vascular dysfunction of migraineurs. We systematically searched in BIOSIS, the Cochrane database, Embase, Google scholar, ISI Web of Science, and Medline to identify articles, published up to April 2013, evaluating the endothelial and arterial function of migraineurs. Several lines of evidence for vascular dysfunction were reported in migraineurs. Findings regarding endothelial function are particularly controversial since studies variously indicated the presence of endothelial dysfunction in migraineurs, the absence of any difference in endothelial function between migraineurs and non-migraineurs, and even an enhanced endothelial function in migraineurs. Reports on arterial function are more consistent and suggest that functional properties of large arteries are altered in migraineurs. Peripheral vascular function, particularly arterial function, is a promising non-invasive indicator of the vascular health of subjects with migraine. However, further targeted research is needed to understand whether altered arterial function explains the increased risk of vascular disease among patients with migraine. PMID:24083826

  9. Intraspecific scaling laws of vascular trees.

    PubMed

    Huo, Yunlong; Kassab, Ghassan S

    2012-01-07

    A fundamental physics-based derivation of intraspecific scaling laws of vascular trees has not been previously realized. Here, we provide such a theoretical derivation for the volume-diameter and flow-length scaling laws of intraspecific vascular trees. In conjunction with the minimum energy hypothesis, this formulation also results in diameter-length, flow-diameter and flow-volume scaling laws. The intraspecific scaling predicts the volume-diameter power relation with a theoretical exponent of 3, which is validated by the experimental measurements for the three major coronary arterial trees in swine (where a least-squares fit of these measurements has exponents of 2.96, 3 and 2.98 for the left anterior descending artery, left circumflex artery and right coronary artery trees, respectively). This scaling law as well as others agrees very well with the measured morphometric data of vascular trees in various other organs and species. This study is fundamental to the understanding of morphological and haemodynamic features in a biological vascular tree and has implications for vascular disease.

  10. Retinal vascular segmentation using superpixel-based line operator and its application to vascular topology estimation.

    PubMed

    Na, Tong; Xie, Jianyang; Zhao, Yitian; Zhao, Yifan; Liu, Yue; Wang, Yongtian; Liu, Jiang

    2018-05-09

    Automatic methods of analyzing of retinal vascular networks, such as retinal blood vessel detection, vascular network topology estimation, and arteries/veins classification are of great assistance to the ophthalmologist in terms of diagnosis and treatment of a wide spectrum of diseases. We propose a new framework for precisely segmenting retinal vasculatures, constructing retinal vascular network topology, and separating the arteries and veins. A nonlocal total variation inspired Retinex model is employed to remove the image intensity inhomogeneities and relatively poor contrast. For better generalizability and segmentation performance, a superpixel-based line operator is proposed as to distinguish between lines and the edges, thus allowing more tolerance in the position of the respective contours. The concept of dominant sets clustering is adopted to estimate retinal vessel topology and classify the vessel network into arteries and veins. The proposed segmentation method yields competitive results on three public data sets (STARE, DRIVE, and IOSTAR), and it has superior performance when compared with unsupervised segmentation methods, with accuracy of 0.954, 0.957, and 0.964, respectively. The topology estimation approach has been applied to five public databases (DRIVE,STARE, INSPIRE, IOSTAR, and VICAVR) and achieved high accuracy of 0.830, 0.910, 0.915, 0.928, and 0.889, respectively. The accuracies of arteries/veins classification based on the estimated vascular topology on three public databases (INSPIRE, DRIVE and VICAVR) are 0.90.9, 0.910, and 0.907, respectively. The experimental results show that the proposed framework has effectively addressed crossover problem, a bottleneck issue in segmentation and vascular topology reconstruction. The vascular topology information significantly improves the accuracy on arteries/veins classification. © 2018 American Association of Physicists in Medicine.

  11. Radiation hazards to vascular surgeon and scrub nurse in mobile fluoroscopy equipped hybrid vascular room

    PubMed Central

    Kim, Jong Bin; Lee, Jaehoon

    2017-01-01

    Purpose The aim of the present study was to identify the radiation hazards to vascular surgeons and scrub nurses working in mobile fluoroscopy equipped hybrid vascular operation rooms; additionally, to estimate cumulative cancer risk due to certain exposure dosages. Methods The study was conducted prospectively in 71 patients (53 men and 18 women) who had undergone vascular intervention at our hybrid vascular theater for 6 months. OEC 9900 fluoroscopy was used as mobile C-arm. Exposure dose (ED) was measured by attaching optically stimulated luminescence at in and outside of the radiation protectors. To measure X-ray scatter with the anthropomorphic phantom model, the dose was measured at 3 distances (20, 50, 100 cm) and 3 angles (horizontal, upward 45°, downward 45°) using a personal gamma radiation dosimeter, Ecotest CARD DKG-21, for 1, 3, 5, 10 minutes. Results Lifetime attributable risk of cancer was estimated using the approach of the Biological Effects of Ionizing Radiation report VII. The 6-month ED of vascular surgeons and scrub nurses were 3.85, 1.31 mSv, respectively. The attenuation rate of lead apron, neck protector and goggle were 74.6%, 60.6%, and 70.1%, respectively. All cancer incidences among surgeons and scrub nurses correspond to 2,355 and 795 per 100,000 persons. The 10-minute dose at 100-cm distance was 0.004 mSv at horizontal, 0.009 mSv at downward 45°, 0.003 mSv at upward 45°. Conclusion Although yearly radiation hazards for vascular surgeons and scrub nurses are still within safety guidelines, protection principles can never be too stringent when aiming to minimize the cumulative harmful effects. PMID:28289670

  12. Constructal Law of Vascular Trees for Facilitation of Flow

    PubMed Central

    Razavi, Mohammad S.; Shirani, Ebrahim; Salimpour, Mohammad Reza; Kassab, Ghassan S.

    2014-01-01

    Diverse tree structures such as blood vessels, branches of a tree and river basins exist in nature. The constructal law states that the evolution of flow structures in nature has a tendency to facilitate flow. This study suggests a theoretical basis for evaluation of flow facilitation within vascular structure from the perspective of evolution. A novel evolution parameter (Ev) is proposed to quantify the flow capacity of vascular structures. Ev is defined as the ratio of the flow conductance of an evolving structure (configuration with imperfection) to the flow conductance of structure with least imperfection. Attaining higher Ev enables the structure to expedite flow circulation with less energy dissipation. For both Newtonian and non-Newtonian fluids, the evolution parameter was developed as a function of geometrical shape factors in laminar and turbulent fully developed flows. It was found that the non-Newtonian or Newtonian behavior of fluid as well as flow behavior such as laminar or turbulent behavior affects the evolution parameter. Using measured vascular morphometric data of various organs and species, the evolution parameter was calculated. The evolution parameter of the tree structures in biological systems was found to be in the range of 0.95 to 1. The conclusion is that various organs in various species have high capacity to facilitate flow within their respective vascular structures. PMID:25551617

  13. Engineering vascularized soft tissue flaps in an animal model using human adipose–derived stem cells and VEGF+PLGA/PEG microspheres on a collagen-chitosan scaffold with a flow-through vascular pedicle

    PubMed Central

    Zhang, Qixu; Hubenak, Justin; Iyyanki, Tejaswi; Alred, Erik; Turza, Kristin C.; Davis, Greg; Chang, Edward I.; Branch-Brooks, Cynthia D.; Beahm, Elisabeth K.; Butler, Charles E.

    2015-01-01

    Insufficient neovascularization is associated with high levels of resorption and necrosis in autologous and engineered fat grafts. We tested the hypothesis that incorporating angiogenic growth factor into a scaffold–stem cell construct and implanting this construct around a vascular pedicle improves neovascularization and adipogenesis for engineering soft tissue flaps. Poly(lactic-co-glycolic-acid/polyethylene glycol (PLGA/PEG) microspheres containing vascular endothelial growth factor (VEGF) were impregnated into collagen-chitosan scaffolds seeded with human adipose-derived stem cells (hASCs). This setup was analyzed in vitro and then implanted into isolated chambers around a discrete vascular pedicle in nude rats. Engineered tissue samples within the chambers were harvested and analyzed for differences in vascularization and adipose tissue growth. In vitro testing showed that the collagen-chitosan scaffold provided a supportive environment for hASC integration and proliferation. PLGA/PEG microspheres with slow-release VEGF had no negative effect on cell survival in collagen-chitosan scaffolds. In vivo, the system resulted in a statistically significant increase in neovascularization that in turn led to a significant increase in adipose tissue persistence after 8 weeks versus control constructs. These data indicate that our model—hASCs integrated with a collagen-chitosan scaffold incorporated with VEGF-containing PLGA/PEG microspheres supported by a predominant vascular vessel inside a chamber—provides a promising, clinically translatable platform for engineering vascularized soft tissue flap. The engineered adipose tissue with a vascular pedicle could conceivably be transferred as a vascularized soft tissue pedicle flap or free flap to a recipient site for the repair of soft-tissue defects. PMID:26410787

  14. Multimodality Intra-Arterial Imaging Assessment of the Vascular Trauma Induced by Balloon-Based and Nonballoon-Based Renal Denervation Systems.

    PubMed

    Karanasos, Antonios; Van Mieghem, Nicolas; Bergmann, Martin W; Hartman, Eline; Ligthart, Jurgen; van der Heide, Elco; Heeger, Christian-H; Ouhlous, Mohamed; Zijlstra, Felix; Regar, Evelyn; Daemen, Joost

    2015-07-01

    Renal denervation is a new treatment considered for several possible indications. As new systems are introduced, the incidence of acute renal artery wall injury with relation to the denervation method is unknown. We investigated the acute repercussion of renal denervation on the renal arteries of patients treated with balloon-based and nonballoon-based denervation systems by quantitative angiography, intravascular ultrasound, and optical coherence tomography (OCT). Twenty-five patients (50 renal arteries) underwent bilateral renal denervation with 5 different systems, 3 of which balloon-based (Paradise [n=5], Oneshot [n=6], and Vessix V2 [n=5)]) and 2 nonballoon-based (Symplicity [n=6] and EnligHTN [n=3]). Analysis included quantitative angiography and morphometric intravascular ultrasound measurements pre and post procedure and assessment of vascular trauma (dissection, edema, or thrombus) by OCT after denervation. A significant reduction in lumen size by quantitative angiography and intravascular ultrasound was observed in nonballoon denervation but not in balloon denervation. By postdenervation OCT, dissection was seen in 14 arteries (32.6%). The percentage of frames with dissection was higher in balloon-based denervation catheters. Thrombus and edema were detected in 35 (81.4%) and 32 (74.4%) arteries, respectively. In arteries treated with balloon-based denervation that had dissection by OCT, the balloon/artery ratio was higher (1.24 [1.17-1.32] versus 1.10 [1.04-1.18]; P<0.01). A varying extent of vascular injury was observed after renal denervation in all systems; however, different patterns were identified in balloon-based and in nonballoon-based denervation systems. In balloon denervation, the presence of dissections by OCT was associated with a higher balloon/artery ratio. © 2015 American Heart Association, Inc.

  15. Sirtuins, Cell Senescence, and Vascular Aging.

    PubMed

    Kida, Yujiro; Goligorsky, Michael S

    2016-05-01

    The sirtuins (SIRTs) constitute a class of proteins with nicotinamide adenine dinucleotide-dependent deacetylase or adenosine diphosphate-ribosyltransferase activity. Seven SIRT family members have been identified in mammals, from SIRT1, the best studied for its role in vascular aging, to SIRT7. SIRT1 and SIRT2 are localized in the nucleus and cytoplasm. SIRT3, SIRT4, and SIRT5 are mitochondrial, and SIRT6 and SIRT7 are nuclear. Extensive studies have clearly revealed that SIRT proteins regulate diverse cell functions and responses to stressors. Vascular aging involves the aging process (senescence) of endothelial and vascular smooth muscle cells. Two types of cell senescence have been identified: (1) replicative senescence with telomere attrition; and (2) stress-induced premature senescence without telomere involvement. Both types of senescence induce vascular cell growth arrest and loss of vascular homeostasis, and contribute to the initiation and progression of cardiovascular diseases. Previous mechanistic studies have revealed in detail that SIRT1, SIRT3, and SIRT6 show protective functions against vascular aging, and definite vascular function of other SIRTs is under investigation. Thus, direct SIRT modulation and nicotinamide adenine dinucleotide stimulation of SIRT are promising candidates for cardiovascular disease therapy. A small number of pilot studies have been conducted to assess SIRT modulation in humans. These clinical studies have not yet provided convincing evidence that SIRT proteins alleviate morbidity and mortality in patients with cardiovascular diseases. The outcomes of multiple ongoing clinical trials are awaited to define the efficacy of SIRT modulators and SIRT activators in cardiovascular diseases, along with the potential adverse effects of chronic SIRT modulation. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  16. [Vascular aging, arterial hypertension and physical activity].

    PubMed

    Schmidt-Trucksäss, A; Weisser, B

    2011-11-01

    The present review delineates the significance of intima-media-thickness, arterial stiffness and endothelial function for vascular aging. There is profound evidence for an increase in intima-media-thickness and vascular stiffness not only during healthy aging but induced also by cardiovascular risk factors. There is a central role of arterial hypertension for this progression in both structural factors. In addition, both parameters are strongly associated with cardiovascular risk. Endothelial function measured as postischemic flow-mediated vasodilatation is a functional parameter which is decreased both in healthy aging and by cardiovascular risk factors. Physical activity modifies the influence of aging and risk factors on endothelial function. A positive influence of endurance exercise on vascular stiffness and endothelial function has been demonstrated in numerous studies. In long-term studies, regular physical activity has been shown to reduce the progression of intima-media-thickness. Thus, arterial hypertension accelerates vascular aging, while physical activity has a positive influence on a variety of vascular parameters associated with vascular aging. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Redox signaling, Nox5 and vascular remodeling in hypertension.

    PubMed

    Montezano, Augusto C; Tsiropoulou, Sofia; Dulak-Lis, Maria; Harvey, Adam; Camargo, Livia De Lucca; Touyz, Rhian M

    2015-09-01

    Extensive data indicate a role for reactive oxygen species (ROS) and redox signaling in vascular damage in hypertension. However, molecular mechanisms underlying these processes remain unclear, but oxidative post-translational modification of vascular proteins is critical. This review discusses how proteins are oxidatively modified and how redox signaling influences vascular smooth muscle cell growth and vascular remodeling in hypertension. We also highlight Nox5 as a novel vascular ROS-generating oxidase. Oxidative stress in hypertension leads to oxidative imbalance that affects vascular cell function through redox signaling. Many Nox isoforms produce ROS in the vascular wall, and recent findings show that Nox5 may be important in humans. ROS regulate signaling by numerous processes including cysteine oxidative post-translational modification such as S-nitrosylation, S-glutathionylation and sulfydration. In vascular smooth muscle cells, this influences cellular responses to oxidative stimuli promoting changes from a contractile to a proliferative phenotype. In hypertension, Nox-induced ROS production is increased, leading to perturbed redox signaling through oxidative modifications of vascular proteins. This influences mitogenic signaling and cell cycle regulation, leading to altered cell growth and vascular remodeling in hypertension.

  18. Vascular nanomedicine: Site specific delivery of elastin stabilizing therapeutics to damaged arteries

    NASA Astrophysics Data System (ADS)

    Sinha, Aditi

    Elastin, a structural protein in the extra-cellular matrix, plays a critical role in the normal functioning of blood vessels. Apart from performing its primary function of providing resilience to arteries, it also plays major role in regulating cell-cell and cell-matrix interactions, response to injury, and morphogenesis. Medial arterial calcification (MAC) and abdominal aortic aneurysm (AAA) are two diseases where the structural and functional integrity of elastin is severely compromised. Although the clinical presentation of MAC and AAA differ, they have one common underlying causative mechanism---pathological degradation of elastin. Hence prevention of elastin degradation in the early stages of MAC and AAA can mitigate, partially if not wholly, the fatal consequences of both the diseases. The work presented here is motivated by the overwhelming statistics of people afflicted by elastin associated cardiovascular diseases and the unavailability of cure for the same. Overall goal of our research is to understand role of elastin degradation in cardiovascular diseases and to develop a targeted vascular drug delivery system that is minimally invasive, biodegradable, and non-toxic, that prevents elastin from degradation. Our hope is that such treatment will also help regenerate elastin, thereby providing a multi-fold treatment option for elasto-degenerative vascular diseases. For this purpose, we have first confirmed the combined role of degraded elastin and hyperglycemia in the pathogenesis of MAC. We have shown that in the absence of degraded elastin and TGF-beta1 (abundantly present in diabetic arteries) vascular smooth muscle cells maintain their homeostatic state, regardless of environmental glucose concentrations. However simultaneous exposure to glucose, elastin peptides and TGF-beta1 causes the pathological transgenesis of vascular cells to osteoblast-like cells. We show that plant derived polyphenols bind to vascular elastin with great affinity resulting in

  19. Structural and immunohistochemical changes in the hepatic vascular system in compensated and decompensated stenosis of the pulmonary trunk.

    PubMed

    Novikov, Yu V; Shormanov, S V; Kulikov, S V

    2012-01-01

    Modeling of pulmonary trunk stenosis leads to an increase in hepatic vascular resistance because of veno-arterial and veno-venous reactions. During the compensation phase, bundles of intimal musculature and myoelastic sphincters appear in the arteries, while in the efferent veins hypertrophy of the muscle rolls is observed. The decompensation phase of stenosis is characterized by relaxation of hepatic vascular walls, reduction of the number of arteries with intimal muscles and sphincter structures, and atrophy of muscle rolls in hepatic veins. Sclerotic changes develop in the vascular bed. Failure of the compensatory reactions results in development of chronic hepatic venous plethora with typical morphological manifestations.

  20. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange

    PubMed Central

    Porter, William Ruger; Witmer, Lawrence M.

    2015-01-01

    Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature

  1. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    PubMed

    Porter, William Ruger; Witmer, Lawrence M

    2015-01-01

    Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature

  2. Lipidomics in vascular health: current perspectives.

    PubMed

    Kolovou, Genovefa; Kolovou, Vana; Mavrogeni, Sophie

    2015-01-01

    Identifying the mechanisms that convert a healthy vascular wall to an atherosclerotic wall is of major importance since the consequences may lead to a shortened lifespan. Classical risk factors (age, smoking, obesity, diabetes mellitus, hypertension, and dyslipidemia) may result in the progression of atherosclerotic lesions by processes including inflammation and lipid accumulation. Thus, the evaluation of blood lipids and the full lipid complement produced by cells, organisms, or tissues (lipidomics) is an issue of importance. In this review, we shall describe the recent progress in vascular health research using lipidomic advances. We will begin with an overview of vascular wall biology and lipids, followed by a short analysis of lipidomics. Finally, we shall focus on the clinical implications of lipidomics and studies that have examined lipidomic approaches and vascular health.

  3. Vascular Cures

    MedlinePlus

    ... SV Gives Search ©2017 Vascular Cures is a tax-exempt, nonprofit organization tax ID#: 94-2825216 as described in the Section ... 3) of the Internal Revenue Code. Donations are tax deductible. 274 Redwood Shores Parkway, #717, Redwood City, ...

  4. [Vascular and neurological complications of supracondylar humeral fractures in children].

    PubMed

    Masár, J

    2007-10-01

    The author reports two cases of pediatric patients with supracondylar humeral fractures complicated by concomitant vascular injury. One of the patients also presented with neurological symptoms from compression of the ulnar and median nerves. In the case of vascular injury only, it was necessary to resect a 1-cm segment of the brachial artery which was thrombosed due to intimal disruption. In the other case, surgery was not indicated immediately; however, liberation of the nervus ulnaris and nervus medianus was later required because of nerve compression by the scar and bone. The author considers the exact diagnosis, precise reduction and stable fixation of a fracture to be most important for a good outcome of treatment. Any associated vascular injury is indicated for surgery only after a thorough diagnostic consideration, and may not be needed in every case. The most decisive factor is the clinical presentation. Injury to the nerve system is indicated for surgical treatment at a later period, at 3 months post-injury at the earliest.

  5. Vascular endothelial growth factors: A comparison between invertebrates and vertebrates.

    PubMed

    Kipryushina, Yulia O; Yakovlev, Konstantin V; Odintsova, Nelly A

    2015-12-01

    This review aims to summarize recent data concerning the structure and role of the members of the vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGFR) families in the context of early development, organogenesis and regeneration, with a particular emphasis on the role of these factors in the development of invertebrates. Homologs of VEGF and/or VEGFR have been found in all Eumetazoa, in both Radiata and Bilateria, where they are expressed in the descendants of different germ layers and play a pivotal role in the development of animals with and without a vascular system. VEGF is a well-known angiogenesis regulator, but this factor also control cell migration during neurogenesis and the development of branching organs (the trachea) in invertebrate and vertebrate species. A possible explanation for the origin of Vegf/Vegfr in the animal kingdom and a pathway of Vegf/Vegfr evolution are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. [Vascular access guidelines for hemodialysis].

    PubMed

    Rodríguez Hernández, J A; González Parra, E; Julián Gutiérrez, J M; Segarra Medrano, A; Almirante, B; Martínez, M T; Arrieta, J; Fernández Rivera, C; Galera, A; Gallego Beuter, J; Górriz, J L; Herrero, J A; López Menchero, R; Ochando, A; Pérez Bañasco, V; Polo, J R; Pueyo, J; Ruiz, Camps I; Segura Iglesias, R

    2005-01-01

    Quality of vascular access (VA) has a remarkable influence in hemodialysis patients outcomes. Dysfunction of VA represents a capital cause of morbi-mortality of these patients as well an increase in economical. Spanish Society of Neprhology, aware of the problem, has decided to carry out a revision of the issue with the aim of providing help in comprehensión and treatment related with VA problems, and achieving an homogenization of practices in three mayor aspects: to increase arteriovenous fistula utilization as first vascular access, to increment vascular access monitoring practice and rationalise central catheters use. We present a consensus document elaborated by a multidisciplinar group composed by nephrologists, vascular surgeons, interventional radiologysts, infectious diseases specialists and nephrological nurses. Along six chapters that cover patient education, creation of VA, care, monitoring, complications and central catheters, we present the state of the art and propose guidelines for the best practice, according different evidence based degrees, with the intention to provide help at the professionals in order to make aproppiate decissions. Several quality standars are also included.

  7. MicroRNA-133 controls vascular smooth muscle cell phenotypic switch in vitro and vascular remodeling in vivo.

    PubMed

    Torella, Daniele; Iaconetti, Claudio; Catalucci, Daniele; Ellison, Georgina M; Leone, Angelo; Waring, Cheryl D; Bochicchio, Angela; Vicinanza, Carla; Aquila, Iolanda; Curcio, Antonio; Condorelli, Gianluigi; Indolfi, Ciro

    2011-09-30

    MicroRNA (miR)-1 and -133 play a crucial role in skeletal and cardiac muscle biology and pathophysiology. However, their expression and regulation in vascular cell physiology and disease is currently unknown. The aim of the present study was to evaluate the role, if any, of miR-1 and miR-133 in vascular smooth muscle cell (VSMC) phenotypic switch in vitro and in vivo. We demonstrate here that miR-133 is robustly expressed in vascular smooth muscle cells (VSMCs) in vitro and in vivo, whereas miR-1 vascular levels are negligible. miR-133 has a potent inhibitory role on VSMC phenotypic switch in vitro and in vivo, whereas miR-1 does not have any relevant effect per se. miR-133 expression is regulated by extracellular signal-regulated kinase 1/2 activation and is inversely correlated with VSMC growth. Indeed, miR-133 decreases when VSMCs are primed to proliferate in vitro and following vascular injury in vivo, whereas it increases when VSMCs are coaxed back to quiescence in vitro and in vivo. miR-133 loss- and gain-of-function experiments show that miR-133 plays a mechanistic role in VSMC growth. Accordingly, adeno-miR-133 reduces but anti-miR-133 exacerbates VSMC proliferation and migration in vitro and in vivo. miR-133 specifically suppresses the transcription factor Sp-1 expression in vitro and in vivo and through Sp-1 repression regulates smooth muscle gene expression. Our data show that miR-133 is a key regulator of vascular smooth muscle cell phenotypic switch in vitro and in vivo, suggesting its potential therapeutic application for vascular diseases.

  8. The Arabidopsis gene MONOPTEROS encodes a transcription factor mediating embryo axis formation and vascular development.

    PubMed Central

    Hardtke, C S; Berleth, T

    1998-01-01

    The vascular tissues of flowering plants form networks of interconnected cells throughout the plant body. The molecular mechanisms directing the routes of vascular strands and ensuring tissue continuity within the vascular system are not known, but are likely to depend on general cues directing plant cell orientation along the apical-basal axis. Mutations in the Arabidopsis gene MONOPTEROS (MP) interfere with the formation of vascular strands at all stages and also with the initiation of the body axis in the early embryo. Here we report the isolation of the MP gene by positional cloning. The predicted protein product contains functional nuclear localization sequences and a DNA binding domain highly similar to a domain shown to bind to control elements of auxin inducible promoters. During embryogenesis, as well as organ development, MP is initially expressed in broad domains that become gradually confined towards the vascular tissues. These observations suggest that the MP gene has an early function in the establishment of vascular and body patterns in embryonic and post-embryonic development. PMID:9482737

  9. Methodology for the evaluation of vascular surgery manpower in France.

    PubMed

    Berger, L; Mace, J M; Ricco, J B; Saporta, G

    2013-01-01

    The French population is growing and ageing. It is expected to increase by 2.7% by 2020, and the number of individuals over 65 years of age is expected to increase by 3.3 million, a 33% increase, between 2005 and 2020. As the number of vascular surgery procedures is closely associated with the age of a population, it is anticipated that there will be a significant increase in the workload of vascular surgeons. A model is presented to predict changes in vascular surgery activity according to population ageing, including other parameters that could affect workload evolution. Three types of arterial procedures were studied: infrarenal abdominal aortic aneurysm (AAA) surgery, peripheral arterial occlusive disease (PAOD) procedures and carotid artery (CEA) procedures. Data were selected and extracted from the national PMSI (Medical Information System Program) database. Data obtained from 2000 were used to predict data based on an ageing population for 2008. From this model, a weighted index was defined for each group by comparing expected and observed workloads. According to the model, over this 8-year period, there was an overall increase in vascular procedures of 52.2%, with an increase of 89% in PAOD procedures. Between 2000 and 2009, the total increase was 58.0%, with 3.9% for AAA procedures, 101.7% for PAOD procedures and 13.2% for CEA procedures. The weighted model based on an ageing population and corrected by a weighted factor predicted this increase. This weighted model is able to predict the workload of vascular surgeons over the coming years. An ageing population and other factors could result in a significant increase in demand for vascular surgical services. Copyright © 2012 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  10. Vascular oxidative stress: a key factor in the development of hypertension associated with ethanol consumption.

    PubMed

    Ceron, Carla S; Marchi, Katia C; Muniz, Jaqueline J; Tirapelli, Carlos R

    2014-01-01

    The observation that the excessive consumption of ethyl alcohol (ethanol) is associated with high blood pressure is nearing its centennial mark. Mechanisms linking ethanol consumption and hypertension are complex and not fully understood. It is established that chronic ethanol consumption leads to hypertension and that this process is a multimediated event involving increased sympathetic activity, stimulation of the renin-angiotensin-aldosterone system with a subsequent increase in vascular oxidative stress and endothelial dysfunction. Under physiological conditions, reactive oxygen species (ROS) play an important role as a signaling molecule in the control of vascular tone and endothelial function. Increased ROS bioavailability is associated with important processes underlying vascular injury in cardiovascular disease such as endothelial dysfunction, vascular remodeling, and inflammation. Studies focusing on molecular mechanisms showed a link between overproduction of ROS in the vasculature and ethanol-induced hypertension. Of the ROS generated in vascular cells, superoxide anion (O2(-)) and hydrogen peroxide (H2O2) appear to be especially important. Ethanol-mediated generation of O2(-) and H2O2 in vascular tissues is associated with elevations in intracellular calcium ([Ca(2+)]i), reduced nitric oxide (NO) bioavailability, endothelial dysfunction and vasoconstriction. O2(-) can also act as a vascular signaling molecule regulating signaling pathways that lead to vascular contraction. Thus, through increased generation of ROS and activation of redox-sensitive pathways, ethanol induces vascular dysfunction, a response that might contribute to the hypertension associated with ethanol consumption. The present article reviews the role of ROS in vascular (patho)biology of ethanol.

  11. Characterization of vascular lesions in pigs affected by porcine circovirus type 2-systemic disease.

    PubMed

    Resendes, A R; Segalés, J

    2015-05-01

    Vascular lesions and their association with porcine circovirus type 2 (PCV2) were evaluated in multiple organs from 10 pigs affected with PCV2-systemic disease (PCV2-SD). Animals had vascular lesions in multiple organs, consisting of lymphohistiocytic lymphangitis and/or phlebitis, mild to severe necrotizing arteritis, and thrombosis within splenic arterioles and choroid plexus capillaries. Variable amounts of PCV2 nucleic acid detected by in situ hybridization were present within endothelial cells, tunica media myocytes, and perivascular and/or intralesional inflammatory cell infiltrates. PCV2 nucleic acid was detected within endothelial cells of both lymphatic and blood vessels without lesions in the associated tissues. Necrotizing arteritis was principally present in lymph nodes and kidney and consisted of degeneration, necrosis, and pyknosis of myocytes, often with intracytoplasmic, brightly eosinophilic inclusion bodies that were strongly positive for PCV2 nucleic acid. Segmental or circumferential fibrinoid necrosis was mainly present in vessels of the lymph node, spleen, and choroid plexus and was variably associated with PCV2 nucleic acid. Severe lymphangitis associated with strong intralesional PCV2 labeling was frequently detected within the mesenteric and mediastinal lymph nodes and the lamina propria of the ileum. In most tissues, medium and large lymphatics and/or veins often had disruption of the intima and mild mononuclear inflammatory cell infiltration that was variably associated with PCV2 nucleic acid. The present study indicates that vasculitis is a frequent finding in natural cases of PCV2-SD and that PCV2 may have a direct cytopathic effect on tunica media myocytes of small- and medium-sized arteries as well as endothelium. © The Author(s) 2014.

  12. Targeting vascular (endothelial) dysfunction

    PubMed Central

    Steven, Sebastian; Weber, Alina; Shuvaev, Vladimir V.; Muzykantov, Vladimir R.; Laher, Ismail; Li, Huige; Lamas, Santiago

    2016-01-01

    Abstract Cardiovascular diseases are major contributors to global deaths and disability‐adjusted life years, with hypertension a significant risk factor for all causes of death. The endothelium that lines the inner wall of the vasculature regulates essential haemostatic functions, such as vascular tone, circulation of blood cells, inflammation and platelet activity. Endothelial dysfunction is an early predictor of atherosclerosis and future cardiovascular events. We review the prognostic value of obtaining measurements of endothelial function, the clinical techniques for its determination, the mechanisms leading to endothelial dysfunction and the therapeutic treatment of endothelial dysfunction. Since vascular oxidative stress and inflammation are major determinants of endothelial function, we have also addressed current antioxidant and anti‐inflammatory therapies. In the light of recent data that dispute the prognostic value of endothelial function in healthy human cohorts, we also discuss alternative diagnostic parameters such as vascular stiffness index and intima/media thickness ratio. We also suggest that assessing vascular function, including that of smooth muscle and even perivascular adipose tissue, may be an appropriate parameter for clinical investigations. Linked Articles This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc PMID:27187006

  13. Imaging Retinal Vascular Changes in the Mouse Model of Oxygen-Induced Retinopathy

    PubMed Central

    Furtado, João M.; Davies, Michael H.; Choi, Dongseok; Lauer, Andreas K.; Appukuttan, Binoy; Bailey, Steven T.; Rahman, Hassan T.; Payne, John F.; Stempel, Andrew J.; Mohs, Kathleen; Powers, Michael R.; Yeh, Steven; Smith, Justine R.

    2012-01-01

    Purpose Oxygen-induced retinopathy in the mouse is the standard experimental model of retinopathy of prematurity. Assessment of the pathology involves in vitro analysis of retinal vaso-obliteration and retinal neovascularization. The authors studied the clinical features of oxygen-induced retinopathy in vivo using topical endoscopy fundus imaging (TEFI), in comparison to standard investigations, and evaluated a system for grading these features. Methods Postnatal day (P)7 mice were exposed to 75% oxygen for five days to induce retinopathy or maintained in room air as controls. Retinal vascular competence was graded against standard photographs by three masked graders. Retinal photographs were obtained at predetermined ages using TEFI. Postmortem, retinal vaso-obliteration was measured in whole mounts with labeled vasculature, and retinal neovascularization was quantified in hematoxylin- and eosin-stained ocular cross sections. Results Fundus photography by TEFI was possible from P15, when retinal vascular incompetence, including dilatation and tortuosity, was significant in mice with oxygen-induced retinopathy in comparison to controls. Vascular incompetence peaked in severity at P17 and persisted through P25. Comparison with in vitro analyses indicated that vascular changes were most severe after retinal avascularity had begun to decrease in area, and coincident with the maximum of retinal neovascularization. A weighted Fleiss-Cohen kappa indicated good intra- and interobserver agreement for a 5-point grading system. Conclusions Topical endoscopy fundus imaging demonstrates retinal vascular incompetence in mice with oxygen-induced retinopathy. The technique complements standard postmortem analysis for following the course of the model. Translational Relevance Topical endoscopy fundus imaging has application in the evaluation of novel biologic drugs for retinopathy of prematurity. PMID:24049705

  14. Retinal vascular geometry in Asian persons with diabetes and retinopathy.

    PubMed

    Cheung, Carol Yim-lui; Lamoureux, Ecosse; Ikram, M Kamran; Sasongko, M Bayu; Ding, Jie; Zheng, Yingfeng; Mitchell, Paul; Wang, Jie Jin; Wong, Tien Yin

    2012-05-01

    Our purpose was to examine the relationship of retinal vascular parameters with diabetes and retinopathy in an older Asian population. Retinal photographs from participants of a population-based survey of Asian Malay persons aged 40-80 years were analyzed. Specific retinal vascular parameters (tortuosity, branching angle, fractal dimension, and caliber) were measured using a semiautomated computer-based program. Diabetes was defined as random plasma glucose ≥ 11.1 mmol/liter, the use of diabetes medication, or physician-diagnosed diabetes. Retinopathy signs were graded from photographs using the modified Airlie House classification system. A total of 2735 persons were included in the study. Persons with diabetes (n = 594) were more likely to have straighter (less tortuous) arterioles and wider arteriolar and venular caliber than those without diabetes (n = 2141). Among subjects with diabetes, those with retinopathy had wider venular caliber than those without retinopathy (211.3 versus 204.9 mm, p = .001). Among nondiabetic subjects, however, those with retinopathy had more tortuous venules than those without retinopathy [5.19(×10(4)) versus 4.27(×10(4)), p < .001]. Retinal vascular parameters varied by diabetes and retinopathy status in this older Asian cohort. Our findings suggest that subtle alterations in retinal vascular architecture are influenced by diabetes. © 2012 Diabetes Technology Society.

  15. [Vascular anatomy of donor and recipient in living kidney transplantation].

    PubMed

    Zhang, Jiqing; Zhang, Xiaodong

    2009-09-01

    To review the vascular anatomy of the donor and the recipient for the living kidney transplantation. The recent literature about the vessels of donor and recipient in clinical applications was extensively reviewed. The pertinent vascular anatomy of the donor and recipient was essential for the screening of the proper candidates, surgical planning and long-term outcome. Early branching and accessory renal artery of the donor were particularly important to deciding the side of nephrectomy, surgical technique and anastomosing pattern, and their injuries were the most frequent factor of the conversion from laparoscopic to open surgery. With increase of laparoscopic nephrectomy in donors, accurate venous anatomy was paid more and more attention to because venous bleeding could also lead to conversion to open nephrectomy. Multidetector CT (MDCT) could supplant the conventional excretory urography and renal catheter angiography and could accurately depict the donors' vessels, vascular variations. In addition, MDCT can excellently evaluate the status of donor kidney, collecting system and other pertinent anatomy details. Accurate master of related vascular anatomy can facilitate operation plan and success of operation and can contribute to the rapid development of living donor kidney transplantation. MDCT has become the choice of preoperative one-stop image assessment for living renal donors.

  16. Vasa Vasorum Arteriopathy: Relationship With Systemic Arterial Hypertension and Other Vascular Lesions in Cats.

    PubMed

    Kohnken, R; Scansen, B A; Premanandan, C

    2017-05-01

    The vasa vasorum is a delicate network of small arterioles that supplies nutrients to the adventitia and outer media of large arteries. In humans, dysfunction of the vasa vasorum contributes to the pathogenesis of aortic dissection and atherosclerosis. Twenty-four cats from 1 to 18 years of age were prospectively evaluated. Cases were divided into 3 cohorts-with systemic hypertension, without systemic hypertension, and uncertain. Histologic sections of the aorta and main pulmonary artery, as well as sections of kidney and lung, were blindly examined by 2 pathologists. The severity of vasa vasorum arteriopathy was compared to the presence of renal arteriosclerosis, aortic medial degeneration, subintimal fibroplasia of the main pulmonary artery, and blood pressure. We found that vasa vasorum arteriopathy correlated strongly with hypertensive status, degree of renal arteriosclerosis, and lesions in the great vessels. The positive predictive value of a severe vasa vasorum score for systemic hypertension was 84.6%. Lesions of vasa vasorum arteriopathy were predictive of renal arteriosclerosis with 100% sensitivity and 64.7% specificity. The positive predictive value of a severe vasa vasorum score for the presence of aortic lesions was 69.2% vs 91.6% for lesions in the main pulmonary artery. The vasa vasorum appears to be an important responder to systemic hypertension in cats, and arteriopathy of this vascular bed has significant implications for the integrity of the great vessels.

  17. Revascularization of diaphyseal bone segments by vascular bundle implantation.

    PubMed

    Nagi, O N

    2005-11-01

    Vascularized bone transfer is an effective, established treatment for avascular necrosis and atrophic or infected nonunions. However, limited donor sites and technical difficulty limit its application. Vascular bundle transplantation may provide an alternative. However, even if vascular ingrowth is presumed to occur in such situations, its extent in aiding revascularization for ultimate graft incorporation is not well understood. A rabbit tibia model was used to study and compare vascularized, segmental, diaphyseal, nonvascularized conventional, and vascular bundle-implanted grafts with a combination of angiographic, radiographic, histopathologic, and bone scanning techniques. Complete graft incorporation in conventional grafts was observed at 6 months, whereas it was 8 to 12 weeks with either of the vascularized grafts. The pattern of radionuclide uptake and the duration of graft incorporation between vascular segmental bone grafts (with intact endosteal blood supply) and vascular bundle-implanted segmental grafts were similar. A vascular bundle implanted in the recipient bone was found to anastomose extensively with the intraosseous circulation at 6 weeks. Effective revascularization of bone could be seen when a simple vascular bundle was introduced into a segment of bone deprived of its normal blood supply. This simple technique offers promise for improvement of bone graft survival in clinical circumstances.

  18. [Hemangiomas and vascular malformations of the head and neck].

    PubMed

    Hassmann-Poznańska, Elibieta; Kurzyna, Agnieszka

    2006-01-01

    This paper presents the review of current knowledge regarding vascular lesions of the head and neck. For many years the term hemangioma was used to describe all vascular lesions. Mulliken and Glowacki classified congenital vascular lesions and recognized two distinct entities, hemangiomas-vascular tumors and vascular malformations. Hemangiomas are usually not present at birth, proliferate during first year of life and then involute. They are composed of proliferating endothelial cells. Vascular malformations are always present at birth although not always apparent, increase slowly in size throughout whole life and never involute. They enlarge by hypertrophy of malformed vessels. Vascular malformations can be further subdivided according to the type of involved vessels as arterial, arteriovenous, venous, capillary or lymphatic. Accurate diagnosis of hemangiomas and vascular malformations remains a challenge for physicians. Although majority of hemangiomas are self limiting lesions some of them may develop complications such as; ulceration, airway obstruction, ophthalmic complications, psychosocial consequences. Segmental hemangiomas are associated with the risk of structural anomalies such as those that occur in PHACE syndrome. Clinical presentation and forms of treatment of various forms of vascular malformations are presented. Vascular malformations have to be treated according to their histopathology and location, as well as their hemodynamic features shown by radiological examinations.

  19. Hepatic vascular shunts: embryology and imaging appearances

    PubMed Central

    Bhargava, P; Vaidya, S; Kolokythas, O; Katz, D S; Dighe, M

    2011-01-01

    The purpose of this pictorial review is to understand the embryological basis of the development of congenital hepatic vascular shunts and to review the multimodality imaging appearances of congenital and acquired hepatic vascular shunts. Hepatic vascular shunts are commonly seen in imaging. Familiarity with their characteristic appearances is important in order to accurately characterise these shunts and diagnose the underlying disorders. PMID:22101582

  20. Diet Bioactive Compounds: Implications for Oxidative Stress and Inflammation in the Vascular System.

    PubMed

    Gabriele, Morena; Pucci, Laura

    2017-11-16

    Increasing evidence has demonstrated that dietary products and their active components are independently or jointly responsible for the apparent reduction of the cardiovascular diseases (CVDs) risk. Nowadays, there is a growing attention in the use of nutraceuticals as a new approach for the prevention and management of many diseases, as well as for controlling rising of chronic illnesses with minimal side effects. Food-derived peptides, as well as peptide-rich protein hydrolysates, represent new and valuable tools for the prevention of metabolic and cardiovascular diseases, acting as modulators of oxidative stress, inflammation, and overactivity of the renin-angiotensin system (RAS). This review summarizes the recently published data on antioxidant, anti-inflammatory, and vascular protective properties of nutraceuticals, notably on the effects of food-derived bioactive peptides and protein hydrolysates, paying particular attention to those derived from fermented foods. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. The protective role of Sirt1 in vascular tissue: its relationship to vascular aging and atherosclerosis.

    PubMed

    Kitada, Munehiro; Ogura, Yoshio; Koya, Daisuke

    2016-10-15

    Cardiovascular disease (CVD) due to atherosclerosis is the main cause of death in both the elderly and patients with metabolic diseases, including diabetes. Aging processes contribute to the pathogenesis of atherosclerosis. Calorie restriction (CR) is recognized as a dietary intervention for promoting longevity and delaying age-related diseases, including atherosclerosis. Sirt1, an NAD + -dependent deacetylase, is considered an anti-aging molecule and is induced during CR. Sirt1 deacetylates target proteins and is linked to cellular metabolism, the redox state and survival pathways. Sirt1 expression/activation is decreased in vascular tissue undergoing senescence. Sirt1 deficiency in endothelial cells (ECs), vascular smooth muscle cells (VSMCs) and monocytes/macrophages contributes to increased oxidative stress, inflammation, foam cell formation, senescences impaired nitric oxide production and autophagy, thereby promoting vascular aging and atherosclerosis. Endothelial dysfunction, activation of monocytes/macrophages, and the functional and phenotypical plasticity of VSMCs are critically implicated in the pathogenesis of atherosclerosis through multiple mechanisms. Therefore, the activation of Sirt1 in vascular tissue, which includes ECs, monocytes/macrophages and VSMCs, may be a new therapeutic strategy against atherosclerosis and the increasing resistance to the metabolic disorder-related causal factors of CVD. In this review, we discuss the protective role of Sirt1 in the pathophysiology of vascular aging and atherosclerosis.

  2. The protective role of Sirt1 in vascular tissue: its relationship to vascular aging and atherosclerosis

    PubMed Central

    Kitada, Munehiro; Ogura, Yoshio; Koya, Daisuke

    2016-01-01

    Cardiovascular disease (CVD) due to atherosclerosis is the main cause of death in both the elderly and patients with metabolic diseases, including diabetes. Aging processes contribute to the pathogenesis of atherosclerosis. Calorie restriction (CR) is recognized as a dietary intervention for promoting longevity and delaying age-related diseases, including atherosclerosis. Sirt1, an NAD+-dependent deacetylase, is considered an anti-aging molecule and is induced during CR. Sirt1 deacetylates target proteins and is linked to cellular metabolism, the redox state and survival pathways. Sirt1 expression/activation is decreased in vascular tissue undergoing senescence. Sirt1 deficiency in endothelial cells (ECs), vascular smooth muscle cells (VSMCs) and monocytes/macrophages contributes to increased oxidative stress, inflammation, foam cell formation, senescences impaired nitric oxide production and autophagy, thereby promoting vascular aging and atherosclerosis. Endothelial dysfunction, activation of monocytes/macrophages, and the functional and phenotypical plasticity of VSMCs are critically implicated in the pathogenesis of atherosclerosis through multiple mechanisms. Therefore, the activation of Sirt1 in vascular tissue, which includes ECs, monocytes/macrophages and VSMCs, may be a new therapeutic strategy against atherosclerosis and the increasing resistance to the metabolic disorder-related causal factors of CVD. In this review, we discuss the protective role of Sirt1 in the pathophysiology of vascular aging and atherosclerosis. PMID:27744418

  3. Comprehensive automatic assessment of retinal vascular abnormalities for computer-assisted retinopathy grading.

    PubMed

    Joshi, Vinayak; Agurto, Carla; VanNess, Richard; Nemeth, Sheila; Soliz, Peter; Barriga, Simon

    2014-01-01

    One of the most important signs of systemic disease that presents on the retina is vascular abnormalities such as in hypertensive retinopathy. Manual analysis of fundus images by human readers is qualitative and lacks in accuracy, consistency and repeatability. Present semi-automatic methods for vascular evaluation are reported to increase accuracy and reduce reader variability, but require extensive reader interaction; thus limiting the software-aided efficiency. Automation thus holds a twofold promise. First, decrease variability while increasing accuracy, and second, increasing the efficiency. In this paper we propose fully automated software as a second reader system for comprehensive assessment of retinal vasculature; which aids the readers in the quantitative characterization of vessel abnormalities in fundus images. This system provides the reader with objective measures of vascular morphology such as tortuosity, branching angles, as well as highlights of areas with abnormalities such as artery-venous nicking, copper and silver wiring, and retinal emboli; in order for the reader to make a final screening decision. To test the efficacy of our system, we evaluated the change in performance of a newly certified retinal reader when grading a set of 40 color fundus images with and without the assistance of the software. The results demonstrated an improvement in reader's performance with the software assistance, in terms of accuracy of detection of vessel abnormalities, determination of retinopathy, and reading time. This system enables the reader in making computer-assisted vasculature assessment with high accuracy and consistency, at a reduced reading time.

  4. Axon guidance molecules in vascular patterning.

    PubMed

    Adams, Ralf H; Eichmann, Anne

    2010-05-01

    Endothelial cells (ECs) form extensive, highly branched and hierarchically organized tubular networks in vertebrates to ensure the proper distribution of molecular and cellular cargo in the vertebrate body. The growth of this vascular system during development, tissue repair or in disease conditions involves the sprouting, migration and proliferation of endothelial cells in a process termed angiogenesis. Surprisingly, specialized ECs, so-called tip cells, which lead and guide endothelial sprouts, share many feature with another guidance structure, the axonal growth cone. Tip cells are motile, invasive and extend numerous filopodial protrusions sensing growth factors, extracellular matrix and other attractive or repulsive cues in their tissue environment. Axonal growth cones and endothelial tip cells also respond to signals belonging to the same molecular families, such as Slits and Roundabouts, Netrins and UNC5 receptors, Semaphorins, Plexins and Neuropilins, and Eph receptors and ephrin ligands. Here we summarize fundamental principles of angiogenic growth, the selection and function of tip cells and the underlying regulation by guidance cues, the Notch pathway and vascular endothelial growth factor signaling.

  5. Intervisceral artery origins in patients with abdominal aortic aneurysmal disease; evidence for systemic vascular remodelling.

    PubMed

    Bailey, Damian M; Evans, Tom G; Thomas, Kate Gower; White, Richard D; Twine, Chistopher P; Lewis, Michael H; Williams, Ian M

    2016-08-01

    What is the central question of this study? To what extent focal abdominal aortic aneurysmal (AAA) disease is associated with systemic remodelling of the vascular tree remains unknown. The present study examined whether anatomical differences exist between distances of the intervisceral artery origins and AAA location/size in patients with disease compared with healthy patients. What is the main finding and its importance? Intervisceral artery distances were shown to be consistently greater in AAA patients, highlighting the systemic nature of AAA disease that extends proximally to the abdominal aorta and its branches. The anatomical description of the natural variation in visceral artery origins has implications for the design of stent grafts and planning complex open aortic surgery. The initial histopathology of abdominal aortic aneurysmal (AAA) disease is atherosclerotic, later diverting towards a distinctive dilating rather than occlusive aortic phenotype. To what extent focal AAA disease is associated with systemic remodelling of the vascular tree remains unknown. The present study examined whether anatomical differences exist between the intervisceral artery origins and AAA location/size in patients with AAA disease (AAA+) relative to those without (AAA-). Preoperative contrast-enhanced computerized tomograms were reviewed in 90 consecutive AAA+ patients scheduled for open repair who underwent an infrarenal (n = 45), suprarenal (n = 26) or supracoeliac clamp (n = 19). These were compared with 39 age-matched AAA- control patients. Craniocaudal measurements were recorded from the distal origin of the coeliac artery to the superior mesenteric artery and from the origin of the superior mesenteric artery to both renal artery origins. Serial blood samples were obtained for estimation of the glomerular filtration rate before and after surgery. Intervisceral artery origins were shown to be consistently greater in AAA+ patients (P < 0.05 versus AAA-), although

  6. Vascularized bone graft for scaphoid nonunions.

    PubMed

    Mih, Alexander D

    2004-09-01

    Scaphoid fracture nonunion remains a challenging problem that may persist despite traditional methods of bone grafting and internal fixation. The alteration of wrist mechanics created by nonunion as well as the development of avascular necrosis leads to degenerative change of the radiocarpal joint accompanied by loss of motion and pain. The use of a vascularized bone graft has the theoretical benefit of increased blood flow that exceeds that of nonvascularized grafts. Numerous sources of vascularized bone graft have been described, including those from remote sites as well as from the carpus and distal radius. Knowledge of the blood supply to the distal radius has allowed for development of several vascularized bone graft harvest sites. The results of vascularized bone grafting from the distal radius have been encouraging, with numerous authors reporting the successful treatment of scaphoid nonunions.

  7. Involvement of glutathione/glutathione S-transferase antioxidant system in butyrate-inhibited vascular smooth muscle cell proliferation.

    PubMed

    Ranganna, Kasturi; Mathew, Omana P; Yatsu, Frank M; Yousefipour, Zivar; Hayes, Barbara E; Milton, Shirlette G

    2007-11-01

    Vascular smooth muscle cell (VSMC) proliferation is an important etiological factor in vascular proliferative diseases such as primary atherosclerosis, hypertension, arterial and in-stent restenosis, and transplant vasculopathy. Our studies established that butyrate, a bacterial fermentation product of dietary fiber and a chromatin modulator, is a potent inhibitor of VSMC proliferation. The cardiovascular health benefits of a high-fiber diet, the principle source of butyrate in the body, have been known for a long time, however, very little is known about the antiatherogenic potential of butyrate. Because oxidative stress plays an important role in the pathogenesis of atherosclerosis, we examined involvement of the glutathione/glutathione S-transferase (GST) antioxidant system in butyrate's inhibition of VSMC proliferation. Treatment of proliferating VSMCs with butyrate leads to the induction of several GSTs. Interestingly, our study also demonstrated the nuclear localization of GST-P1 (GST-7-7), which is considered to be a cytosolic protein; this was demonstrated using immunostaining and was corroborated by western blotting. Also, the butyrate-induced antiproliferative action, and the induction of GST-P1 and its nuclear localization are downregulated when butyrate is withdrawn. Furthermore, assessment of intracellular glutathione levels reveals their augmentation by butyrate. Conversely, butyrate treatment reduces the levels of reactive oxygen species in VSMCs. Collectively, the butyrate-treatment-related increase in glutathione content, the reduction in reactive oxygen species, the upregulation of GST and the nuclear localization of GST-P1 in growth-arrested VSMCs imply that butyrate's antiproliferative action involves modulation of the cellular redox state. Thus, induction of the glutathione/GST antioxidant system appears to have other regulatory role(s) besides detoxification and regulation of the cellular redox state, for example, cell-cycle control and cell

  8. A Dual-Mode Bioreactor System for Tissue Engineered Vascular Models.

    PubMed

    Bono, N; Meghezi, S; Soncini, M; Piola, M; Mantovani, D; Fiore, Gianfranco Beniamino

    2017-06-01

    In the past decades, vascular tissue engineering has made great strides towards bringing engineered vascular tissues to the clinics and, in parallel, obtaining in-lab tools for basic research. Herein, we propose the design of a novel dual-mode bioreactor, useful for the fabrication (construct mode) and in vitro stimulation (culture mode) of collagen-based tubular constructs. Collagen-based gels laden with smooth muscle cells (SMCs) were molded directly within the bioreactor culture chamber. Based on a systematic characterization of the bioreactor culture mode, constructs were subjected to 10% cyclic strain at 0.5 Hz for 5 days. The effects of cyclic stimulation on matrix re-arrangement and biomechanical/viscoelastic properties were examined and compared vs. statically cultured constructs. A thorough comparison of cell response in terms of cell localization and expression of contractile phenotypic markers was carried out as well. We found that cyclic stimulation promoted cell-driven collagen matrix bi-axial compaction, enhancing the mechanical strength of strained samples with respect to static controls. Moreover, cyclic strain positively affected SMC behavior: cells maintained their contractile phenotype and spread uniformly throughout the whole wall thickness. Conversely, static culture induced a noticeable polarization of cell distribution to the outer rim of the constructs and a sharp reduction in total cell density. Overall, coupling the use of a novel dual-mode bioreactor with engineered collagen-gel-based tubular constructs demonstrated to be an interesting technology to investigate the modulation of cell and tissue behavior under controlled mechanically conditioned in vitro maturation.

  9. FGF-dependent metabolic control of vascular development.

    PubMed

    Yu, Pengchun; Wilhelm, Kerstin; Dubrac, Alexandre; Tung, Joe K; Alves, Tiago C; Fang, Jennifer S; Xie, Yi; Zhu, Jie; Chen, Zehua; De Smet, Frederik; Zhang, Jiasheng; Jin, Suk-Won; Sun, Lele; Sun, Hongye; Kibbey, Richard G; Hirschi, Karen K; Hay, Nissim; Carmeliet, Peter; Chittenden, Thomas W; Eichmann, Anne; Potente, Michael; Simons, Michael

    2017-05-11

    Blood and lymphatic vasculatures are intimately involved in tissue oxygenation and fluid homeostasis maintenance. Assembly of these vascular networks involves sprouting, migration and proliferation of endothelial cells. Recent studies have suggested that changes in cellular metabolism are important to these processes. Although much is known about vascular endothelial growth factor (VEGF)-dependent regulation of vascular development and metabolism, little is understood about the role of fibroblast growth factors (FGFs) in this context. Here we identify FGF receptor (FGFR) signalling as a critical regulator of vascular development. This is achieved by FGF-dependent control of c-MYC (MYC) expression that, in turn, regulates expression of the glycolytic enzyme hexokinase 2 (HK2). A decrease in HK2 levels in the absence of FGF signalling inputs results in decreased glycolysis, leading to impaired endothelial cell proliferation and migration. Pan-endothelial- and lymphatic-specific Hk2 knockouts phenocopy blood and/or lymphatic vascular defects seen in Fgfr1/Fgfr3 double mutant mice, while HK2 overexpression partly rescues the defects caused by suppression of FGF signalling. Thus, FGF-dependent regulation of endothelial glycolysis is a pivotal process in developmental and adult vascular growth and development.

  10. Intraocular and systemic levels of vascular endothelial growth factor in advanced cases of retinopathy of prematurity

    PubMed Central

    Velez-Montoya, Raul; Clapp, Carmen; Rivera, Jose Carlos; Garcia-Aguirre, Gerardo; Morales-Cantón, Virgilio; Fromow-Guerra, Jans; Guerrero-Naranjo, Jose Luis; Quiroz-Mercado, Hugo

    2010-01-01

    Purpose: To measure vitreous, aqueous, subretinal fluid and plasma levels of vascular endothelial growth factor in late stages of retinopathy of prematurity. Methods: Interventional study. We enrolled patients with clinical diagnoses of bilateral stage V retinopathy of prematurity, confirmed by b-scan ultrasound and programmed for vitrectomy. During surgery we took samples from blood, aqueous, vitreous, and subretinal fluids. The vascular endothelial growth factor concentration in each sample was measured by ELISA reaction. A control sample of aqueous, vitreous and blood was taken from patients with congenital cataract programmed for phacoemulsification. For statistical analysis, a Mann–Whitney and a Wilcoxon W test was done with a significant P value of 0.05. Results: We took samples of 16 consecutive patients who met the inclusion criteria. The vascular endothelial growth factor levels in the study group were: aqueous, 76.81 ± 61.89 pg/mL; vitreous, 118.53 ± 65.87 pg/mL; subretinal fluid, 1636.58 ± 356.47 pg/mL; and plasma, 74.64 ± 43.94 pg/mL. There was a statistical difference between the study and the control group (P < 0.001) in the aqueous and vitreous samples. Conclusion: Stage 5 retinopathy of prematurity has elevated intraocular levels of vascular endothelial growth factor, which remains high despite severe retinal lesion. There was no statistical difference in plasma levels of the molecule between the control and study group. PMID:20856587

  11. Tissue vascularization through 3D printing: Will technology bring us flow?

    PubMed

    Paulsen, S J; Miller, J S

    2015-05-01

    Though in vivo models provide the most physiologically relevant environment for studying tissue function, in vitro studies provide researchers with explicit control over experimental conditions and the potential to develop high throughput testing methods. In recent years, advancements in developmental biology research and imaging techniques have significantly improved our understanding of the processes involved in vascular development. However, the task of recreating the complex, multi-scale vasculature seen in in vivo systems remains elusive. 3D bioprinting offers a potential method to generate controlled vascular networks with hierarchical structure approaching that of in vivo networks. Bioprinting is an interdisciplinary field that relies on advances in 3D printing technology along with advances in imaging and computational modeling, which allow researchers to monitor cellular function and to better understand cellular environment within the printed tissue. As bioprinting technologies improve with regards to resolution, printing speed, available materials, and automation, 3D printing could be used to generate highly controlled vascularized tissues in a high throughput manner for use in regenerative medicine and the development of in vitro tissue models for research in developmental biology and vascular diseases. © 2015 Wiley Periodicals, Inc.

  12. Engineering clinically relevant volumes of vascularized bone.

    PubMed

    Roux, Brianna M; Cheng, Ming-Huei; Brey, Eric M

    2015-05-01

    Vascularization remains one of the most important challenges that must be overcome for tissue engineering to be consistently implemented for reconstruction of large volume bone defects. An extensive vascular network is needed for transport of nutrients, waste and progenitor cells required for remodelling and repair. A variety of tissue engineering strategies have been investigated in an attempt to vascularize tissues, including those applying cells, soluble factor delivery strategies, novel design and optimization of bio-active materials, vascular assembly pre-implantation and surgical techniques. However, many of these strategies face substantial barriers that must be overcome prior to their ultimate translation into clinical application. In this review recent progress in engineering vascularized bone will be presented with an emphasis on clinical feasibility. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  13. Engineering vascularized soft tissue flaps in an animal model using human adipose-derived stem cells and VEGF+PLGA/PEG microspheres on a collagen-chitosan scaffold with a flow-through vascular pedicle.

    PubMed

    Zhang, Qixu; Hubenak, Justin; Iyyanki, Tejaswi; Alred, Erik; Turza, Kristin C; Davis, Greg; Chang, Edward I; Branch-Brooks, Cynthia D; Beahm, Elisabeth K; Butler, Charles E

    2015-12-01

    Insufficient neovascularization is associated with high levels of resorption and necrosis in autologous and engineered fat grafts. We tested the hypothesis that incorporating angiogenic growth factor into a scaffold-stem cell construct and implanting this construct around a vascular pedicle improves neovascularization and adipogenesis for engineering soft tissue flaps. Poly(lactic-co-glycolic-acid/polyethylene glycol (PLGA/PEG) microspheres containing vascular endothelial growth factor (VEGF) were impregnated into collagen-chitosan scaffolds seeded with human adipose-derived stem cells (hASCs). This setup was analyzed in vitro and then implanted into isolated chambers around a discrete vascular pedicle in nude rats. Engineered tissue samples within the chambers were harvested and analyzed for differences in vascularization and adipose tissue growth. In vitro testing showed that the collagen-chitosan scaffold provided a supportive environment for hASC integration and proliferation. PLGA/PEG microspheres with slow-release VEGF had no negative effect on cell survival in collagen-chitosan scaffolds. In vivo, the system resulted in a statistically significant increase in neovascularization that in turn led to a significant increase in adipose tissue persistence after 8 weeks versus control constructs. These data indicate that our model-hASCs integrated with a collagen-chitosan scaffold incorporated with VEGF-containing PLGA/PEG microspheres supported by a predominant vascular vessel inside a chamber-provides a promising, clinically translatable platform for engineering vascularized soft tissue flap. The engineered adipose tissue with a vascular pedicle could conceivably be transferred as a vascularized soft tissue pedicle flap or free flap to a recipient site for the repair of soft-tissue defects. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Vascular calcification: When should we interfere in chronic kidney disease patients and how?

    PubMed Central

    Sharaf El Din, Usama Abdel Azim; Salem, Mona Mansour; Abdulazim, Dina Ossama

    2016-01-01

    Chronic kidney disease (CKD) patients are endangered with the highest mortality rate compared to other chronic diseases. Cardiovascular events account for up to 60% of the fatalities. Cardiovascular calcifications affect most of the CKD patients. Most of this calcification is related to disturbed renal phosphate handling. Fibroblast growth factor 23 and klotho deficiency were incriminated in the pathogenesis of vascular calcification through different mechanisms including their effects on endothelium and arterial wall smooth muscle cells. In addition, deficient klotho gene expression, a constant feature of CKD, promotes vascular pathology and shares in progression of the CKD. The role of gut in the etio-pathogenesis of systemic inflammation and vascular calcification is a newly discovered mechanism. This review will cover the medical history, prevalence, pathogenesis, clinical relevance, different tools used to diagnose, the ideal timing to prevent or to withhold the progression of vascular calcification and the different medications and medical procedures that can help to prolong the survival of CKD patients. PMID:27648404

  15. Diagnostic criteria for vascular cognitive disorders: a VASCOG statement.

    PubMed

    Sachdev, Perminder; Kalaria, Raj; O'Brien, John; Skoog, Ingmar; Alladi, Suvarna; Black, Sandra E; Blacker, Deborah; Blazer, Dan G; Chen, Christopher; Chui, Helena; Ganguli, Mary; Jellinger, Kurt; Jeste, Dilip V; Pasquier, Florence; Paulsen, Jane; Prins, Niels; Rockwood, Kenneth; Roman, Gustavo; Scheltens, Philip

    2014-01-01

    Several sets of diagnostic criteria have been published for vascular dementia since the 1960s. The continuing ambiguity in vascular dementia definition warrants a critical reexamination. Participants at a special symposium of the International Society for Vascular Behavioral and Cognitive Disorders (VASCOG) in 2009 critiqued the current criteria. They drafted a proposal for a new set of criteria, later reviewed through multiple drafts by the group, including additional experts and the members of the Neurocognitive Disorders Work Group of the fifth revision of Diagnostic and Statistical Manual (DSM-5) Task Force. Cognitive disorders of vascular etiology are a heterogeneous group of disorders with diverse pathologies and clinical manifestations, discussed broadly under the rubric of vascular cognitive disorders (VCD). The continuum of vascular cognitive impairment is recognized by the categories of Mild Vascular Cognitive Disorder, and Vascular Dementia or Major Vascular Cognitive Disorder. Diagnostic thresholds are defined. Clinical and neuroimaging criteria are proposed for establishing vascular etiology. Subtypes of VCD are described, and the frequent cooccurrence of Alzheimer disease pathology emphasized. The proposed criteria for VCD provide a coherent approach to the diagnosis of this diverse group of disorders, with a view to stimulating clinical and pathologic validation studies. These criteria can be harmonized with the DSM-5 criteria such that an international consensus on the criteria for VCD may be achieved.

  16. Detailed Vascular Anatomy of the Human Retina by Projection-Resolved Optical Coherence Tomography Angiography

    NASA Astrophysics Data System (ADS)

    Campbell, J. P.; Zhang, M.; Hwang, T. S.; Bailey, S. T.; Wilson, D. J.; Jia, Y.; Huang, D.

    2017-02-01

    Optical coherence tomography angiography (OCTA) is a noninvasive method of 3D imaging of the retinal and choroidal circulations. However, vascular depth discrimination is limited by superficial vessels projecting flow signal artifact onto deeper layers. The projection-resolved (PR) OCTA algorithm improves depth resolution by removing projection artifact while retaining in-situ flow signal from real blood vessels in deeper layers. This novel technology allowed us to study the normal retinal vasculature in vivo with better depth resolution than previously possible. Our investigation in normal human volunteers revealed the presence of 2 to 4 distinct vascular plexuses in the retina, depending on location relative to the optic disc and fovea. The vascular pattern in these retinal plexuses and interconnecting layers are consistent with previous histologic studies. Based on these data, we propose an improved system of nomenclature and segmentation boundaries for detailed 3-dimensional retinal vascular anatomy by OCTA. This could serve as a basis for future investigation of both normal retinal anatomy, as well as vascular malformations, nonperfusion, and neovascularization.

  17. Potential Therapeutics for Vascular Cognitive Impairment and Dementia.

    PubMed

    Sun, Miao-Kun

    2017-10-16

    As the human lifespan increases, the number of people affected by age-related dementia is growing at an epidemic pace. Vascular pathology dramatically affects cognitive profiles, resulting in dementia and cognitive impairment. While vascular dementia itself constitutes a medical challenge, hypoperfusion/vascular risk factors enhance amyloid toxicity and other memory-damaging factors and hasten Alzheimer's disease (AD) and other memory disorders' progression, as well as negatively affect treatment outcome. Few therapeutic options are, however, currently available to improve the prognosis of patients with vascular dementia and cognitive impairment, mixed AD dementia with vascular pathology, or other memory disorders. Emerging evidence, however, indicates that, like AD and other memory disorders, synaptic impairment underlies much of the memory impairment in the cognitive decline of vascular cognitive impairment and vascular dementia. Effective rescues of the memory functions might be achieved through synaptic and memory therapeutics, targeting distinct molecular signaling pathways that support the formation of new synapses and maintaining their connections. Potential therapeutic agents include: 1) memory therapeutic agents that rescue synaptic and memory functions after the brain insults; 2) anti-pathologic therapeutics and an effective management of vascular risk factors; and 3) preventative therapeutic agents that achieve memory therapy through functional enhancement. Their development and potential as clinically effective memory therapeutics for vascular cognitive impairment and dementia are discussed in this review. These therapeutic agents are also likely to benefit patients with AD and/or other types of memory disorders. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. [A new specialty is born: Vascular medicine].

    PubMed

    Laroche, J-P

    2016-05-01

    On the 4th of December 2015, the French authorities officially recognized the birth of a specialty in vascular medicine entitled CO-DES cardiology-vascular/vascular Medicine. France is the 7th country to obtain this specialty after Switzerland, Germany, Austria, Czech Republic, Slovakia and Slovenia, six countries in the EEC. It has taken years to achieve a long but exciting experience: we went from hopes to disappointments, sometimes with the blues, but lobbying helping… with sustained confidence. This article tells the story of 30 years of struggle to achieve this vascular medicine specialty. Gaston Bachelard wrote: "Nothing is obvious, nothing is given, all is built." For the construction of vascular medicine, we had to overcome many obstacles, nothing was given to us, everything was conquered. Beware "The specialist is one who knows more and more things about an increasingly restricted field, up to 'knowing everything about nothing"' recalled Ralph Barton Ferry, philosopher; so there is room for modesty and humility but also convictions. The physical examination will remain the basis of our exercise. But let us recall the contributions of all those vascular physicians who practiced in the past, together with those currently active, who built day after day, year after year, a vascular medicine of quality. It is because of the trust of our colleagues and our patients that we can occupy the place that is ours today. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. New aspects of vascular remodelling: the involvement of all vascular cell types.

    PubMed

    McGrath, John C; Deighan, Clare; Briones, Ana M; Shafaroudi, Majid Malekzadeh; McBride, Melissa; Adler, Jeremy; Arribas, Silvia M; Vila, Elisabet; Daly, Craig J

    2005-07-01

    Conventionally, the architecture of arteries is based around the close-packed smooth muscle cells and extracellular matrix. However, the adventitia and endothelium are now viewed as key players in vascular growth and repair. A new dynamic picture has emerged of blood vessels in a constant state of self-maintenance. Recent work raises fundamental questions about the cellular heterogeneity of arteries and the time course and triggering of normal and pathological remodelling. A common denominator emerging in hypertensive remodelling is an early increase in adventitial cell density suggesting that adventitial cells drive remodelling and may initiate subsequent changes such as re-arrangement of smooth muscle cells and extracellular matrix. The organization of vascular smooth muscle cells follows regular arrangements that can be modelled mathematically. In hypertension, new patterns can be quantified in these terms and give insights to how structure affects function. As with smooth muscle, little is known about the organization of the vascular endothelium, or its role in vascular remodelling. Current observations suggest that there may be a close relationship between the helical organization of smooth muscle cells and the underlying pattern of endothelial cells. The function of myoendothelial connections is a topic of great current interest and may relate to the structure of the internal elastic lamina through which the connections must pass. In hypertensive remodelling this must present an organizational challenge. The objective of this paper is to show how the functions of blood vessels depend on their architecture and a continuous interaction of different cell types and extracellular proteins.

  20. KLF2 and KLF4 control endothelial identity and vascular integrity

    PubMed Central

    Sangwung, Panjamaporn; Zhou, Guangjin; Nayak, Lalitha; Chan, E. Ricky; Kang, Dong-Won; Zhang, Rongli; Lu, Yuan; Sugi, Keiki; Fujioka, Hisashi; Shi, Hong; Lapping, Stephanie D.; Ghosh, Chandra C.; Higgins, Sarah J.; Parikh, Samir M.; Jain, Mukesh K.

    2017-01-01

    Maintenance of vascular integrity in the adult animal is needed for survival, and it is critically dependent on the endothelial lining, which controls barrier function, blood fluidity, and flow dynamics. However, nodal regulators that coordinate endothelial identity and function in the adult animal remain poorly characterized. Here, we show that endothelial KLF2 and KLF4 control a large segment of the endothelial transcriptome, thereby affecting virtually all key endothelial functions. Inducible endothelial-specific deletion of Klf2 and/or Klf4 reveals that a single allele of either gene is sufficient for survival, but absence of both (EC-DKO) results in acute death from myocardial infarction, heart failure, and stroke. EC-DKO animals exhibit profound compromise in vascular integrity and profound dysregulation of the coagulation system. Collectively, these studies establish an absolute requirement for KLF2/4 for maintenance of endothelial and vascular integrity in the adult animal. PMID:28239661

  1. The primary vascular dysregulation syndrome: implications for eye diseases

    PubMed Central

    2013-01-01

    Vascular dysregulation refers to the regulation of blood flow that is not adapted to the needs of the respective tissue. We distinguish primary vascular dysregulation (PVD, formerly called vasospastic syndrome) and secondary vascular dysregulation (SVD). Subjects with PVD tend to have cold extremities, low blood pressure, reduced feeling of thirst, altered drug sensitivity, increased pain sensitivity, prolonged sleep onset time, altered gene expression in the lymphocytes, signs of oxidative stress, slightly increased endothelin-1 plasma level, low body mass index and often diffuse and fluctuating visual field defects. Coldness, emotional or mechanical stress and starving can provoke symptoms. Virtually all organs, particularly the eye, can be involved. In subjects with PVD, retinal vessels are stiffer and more irregular, and both neurovascular coupling and autoregulation capacity are reduced while retinal venous pressure is often increased. Subjects with PVD have increased risk for normal-tension glaucoma, optic nerve compartment syndrome, central serous choroidopathy, Susac syndrome, retinal artery and vein occlusions and anterior ischaemic neuropathy without atherosclerosis. Further characteristics are their weaker blood–brain and blood-retinal barriers and the higher prevalence of optic disc haemorrhages and activated astrocytes. Subjects with PVD tend to suffer more often from tinnitus, muscle cramps, migraine with aura and silent myocardial ischaemic and are at greater risk for altitude sickness. While the main cause of vascular dysregulation is vascular endotheliopathy, dysfunction of the autonomic nervous system is also involved. In contrast, SVD occurs in the context of other diseases such as multiple sclerosis, retrobulbar neuritis, rheumatoid arthritis, fibromyalgia and giant cell arteritis. Taking into consideration the high prevalence of PVD in the population and potentially linked pathologies, in the current article, the authors provide

  2. Endothelial C-type natriuretic peptide maintains vascular homeostasis

    PubMed Central

    Moyes, Amie J.; Khambata, Rayomand S.; Villar, Inmaculada; Bubb, Kristen J.; Baliga, Reshma S.; Lumsden, Natalie G.; Xiao, Fang; Gane, Paul J.; Rebstock, Anne-Sophie; Worthington, Roberta J.; Simone, Michela I.; Mota, Filipa; Rivilla, Fernando; Vallejo, Susana; Peiró, Concepción; Sánchez Ferrer, Carlos F.; Djordjevic, Snezana; Caulfield, Mark J.; MacAllister, Raymond J.; Selwood, David L.; Ahluwalia, Amrita; Hobbs, Adrian J.

    2014-01-01

    The endothelium plays a fundamental role in maintaining vascular homeostasis by releasing factors that regulate local blood flow, systemic blood pressure, and the reactivity of leukocytes and platelets. Accordingly, endothelial dysfunction underpins many cardiovascular diseases, including hypertension, myocardial infarction, and stroke. Herein, we evaluated mice with endothelial-specific deletion of Nppc, which encodes C-type natriuretic peptide (CNP), and determined that this mediator is essential for multiple aspects of vascular regulation. Specifically, disruption of CNP leads to endothelial dysfunction, hypertension, atherogenesis, and aneurysm. Moreover, we identified natriuretic peptide receptor–C (NPR-C) as the cognate receptor that primarily underlies CNP-dependent vasoprotective functions and developed small-molecule NPR-C agonists to target this pathway. Administration of NPR-C agonists promotes a vasorelaxation of isolated resistance arteries and a reduction in blood pressure in wild-type animals that is diminished in mice lacking NPR-C. This work provides a mechanistic explanation for genome-wide association studies that have linked the NPR-C (Npr3) locus with hypertension by demonstrating the importance of CNP/NPR-C signaling in preserving vascular homoeostasis. Furthermore, these results suggest that the CNP/NPR-C pathway has potential as a disease-modifying therapeutic target for cardiovascular disorders. PMID:25105365

  3. The power of VEGF (vascular endothelial growth factor) family molecules.

    PubMed

    Thomas, Jean-Leon; Eichmann, Anne

    2013-05-01

    Vascular endothelial growth factors (VEGFs) and their high-affinity tyrosine kinase VEGF receptors (VEGFRs) are key regulators of both angiogenesis and neurogenesis. The current issue of CMLS discusses recent literature and work implementing these signals in nervous system development, maintenance and disease pathology.

  4. Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish

    EPA Science Inventory

    Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish Tamara Tal, Integrated Systems Toxicology Division, U.S. EPA Background: There are tens of thousands of chemicals that have yet to be fully evaluated for their toxicity by validated in vivo testing ...

  5. Incorporating simulation in vascular surgery education.

    PubMed

    Bismuth, Jean; Donovan, Michael A; O'Malley, Marcia K; El Sayed, Hosam F; Naoum, Joseph J; Peden, Eric K; Davies, Mark G; Lumsden, Alan B

    2010-10-01

    The traditional apprenticeship model introduced by Halsted of "learning by doing" may just not be valid in the modern practice of vascular surgery. The model is often criticized for being somewhat unstructured because a resident's experience is based on what comes through the "door." In an attempt to promote uniformity of training, multiple national organizations are currently delineating standard curricula for each trainee to govern the knowledge and cases required in a vascular residency. However, the outcomes are anything but uniform. This means that we graduate vascular specialists with a surprisingly wide spectrum of abilities. Use of simulation may benefit trainees in attaining a level of technical expertise that will benefit themselves and their patients. Furthermore, there is likely a need to establish a simulation-based certification process for graduating trainees to further ascertain minimum technical abilities. Copyright © 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  6. Effect of histidine on sorafenib-induced vascular damage: Analysis using novel medaka fish model.

    PubMed

    Shinagawa-Kobayashi, Yoko; Kamimura, Kenya; Goto, Ryo; Ogawa, Kohei; Inoue, Ryosuke; Yokoo, Takeshi; Sakai, Norihiro; Nagoya, Takuro; Sakamaki, Akira; Abe, Satoshi; Sugitani, Soichi; Yanagi, Masahiko; Fujisawa, Koichi; Nozawa, Yoshizu; Koyama, Naoto; Nishina, Hiroshi; Furutani-Seiki, Makoto; Sakaida, Isao; Terai, Shuji

    2018-02-05

    Sorafenib (SFN) is an anti-angiogenic chemotherapeutic that prolongs survival of patients with hepatocellular carcinoma (HCC); its side effects, including vascular damages such as hand-foot syndrome (HFS), are a major cause of therapy discontinuation. We previously reported that maintenance of peripheral blood flow by intake of dried bonito broth (DBB) significantly prevented HFS and prolonged the administration period. The amino acids contained in DBB probably contribute to its effects, but the mechanism has not been clarified. We hypothesized that histidine, the largest component among the amino acids contained in DBB, has effects on SFN-induced vascular damage, and evaluated this possibility using a novel medaka fish model. The fli::GFP transgenic medaka fish model has a fluorescently visible systemic vasculature. We fed the fish with SFN with and without histidine to compare blood flow and vascular structure among the differently fed models. The vascular cross-sectional area of each fish was measured to determine vascular diameter changes. Our results demonstrated that SFN-fed medaka developed a narrower vascular diameter. In addition, this narrowing was counteracted by addition of histidine to the medaka diet. We observed no positive effect of histidine on regeneration of cut vessels or on cell growth of endothelial cells and HCC cell lines. We proved the efficacy of the medaka model to assess vascular changes after administration of specific chemicals. And our results suggest that SFN causes vascular damage by narrowing peripheral vessel diameter, and that histidine effectively counteracts these changes to maintain blood flow. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Three-dimensional vascular mapping of the breast by using contrast-enhanced MRI: association of unilateral increased vascularity with ipsilateral breast cancer.

    PubMed

    Orgüç, Şebnem; Başara, Işıl; Coşkun, Teoman; Pekindil, Gökhan

    2012-01-01

    We aimed to retrospectively compare three-dimensional vascular maps of both breasts obtained by dynamic magnetic resonance imaging (MRI) and determine the association of one-sided vascular prominence with ipsilateral breast cancer. MRI was performed using gadolinium in 194 cases. Two readers scored vascular density using maximum intensity projections (MIPs). Dynamic fat-saturated T1-weighted gradientecho MIPs were acquired. Two readers evaluated the MIPs, and vessels greater than 2 mm in diameter and longer than 3 cm were counted. The difference in vessel numbers detected in the two breasts determined the score. A total of 54 patients had malignant lesions (prevalence, 28%), including invasive ductal carcinoma (n=40), invasive mixed ductal-lobular carcinoma (n=5), invasive lobular carcinoma (n=3), ductal carcinoma in situ (n=3), mucinous carcinoma (n=1), medullary carcinoma (n=1), and leukemic metastasis (n=1). In 62 patients, there were benign lesions (fibroadenomas, fibrocysts), and four patients had inflammation (granulomatous mastitis in two patients, breast tuberculosis in two patients). There were 78 normal cases. When a difference of at least two vessels was scored as vascular asymmetry, the sensitivity, specificity, positive likelihood ratio (+LR), and negative (-LR) of unilaterally increased vascularity associated with ipsilateral malignancy were 69%, 92%, 8.72, and 0.34, respectively. When four infection and three post-operative cases with vascular asymmetry were excluded; prevalence, specificity, and +LR increased to 29%, 97%, and 22.8, respectively, with the same sensitivity and -LR. Differences in mean vascularity scores were evaluated with regard to tumor size. T1 and T2 tumors were not significantly different from each other. The mean score of T3 tumors differed significantly from T1 and T2 tumors. MRI vascular mapping is an effective method for determining breast tissue vascularization. Ipsilateral increased vascularity was commonly associated with

  8. 3D-Printed Biodegradable Polymeric Vascular Grafts.

    PubMed

    Melchiorri, A J; Hibino, N; Best, C A; Yi, T; Lee, Y U; Kraynak, C A; Kimerer, L K; Krieger, A; Kim, P; Breuer, C K; Fisher, J P

    2016-02-04

    Congenital heart defect interventions may benefit from the fabrication of patient-specific vascular grafts because of the wide array of anatomies present in children with cardiovascular defects. 3D printing is used to establish a platform for the production of custom vascular grafts, which are biodegradable, mechanically compatible with vascular tissues, and support neotissue formation and growth. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Mapping and Quantification of Vascular Branching in Plants, Animals and Humans by VESGEN Software

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia A.; Vickerman, Mary B.; Keith, Patricia A.

    2010-01-01

    Humans face daunting challenges in the successful exploration and colonization of space, including adverse alterations in gravity and radiation. The Earth-determined biology of humans, animals and plants is significantly modified in such extraterrestrial environments. One physiological requirement shared by humans with larger plants and animals is a complex, highly branching vascular system that is dynamically responsive to cellular metabolism, immunological protection and specialized cellular/tissue function. The VESsel GENeration (VESGEN) Analysis has been developed as a mature beta version, pre-release research software for mapping and quantification of the fractal-based complexity of vascular branching. Alterations in vascular branching pattern can provide informative read-outs of altered vascular regulation. Originally developed for biomedical applications in angiogenesis, VESGEN 2D has provided novel insights into the cytokine, transgenic and therapeutic regulation of angiogenesis, lymphangiogenesis and other microvascular remodeling phenomena. Vascular trees, networks and tree-network composites are mapped and quantified. Applications include disease progression from clinical ophthalmic images of the human retina; experimental regulation of vascular remodeling in the mouse retina; avian and mouse coronary vasculature, and other experimental models in vivo. We envision that altered branching in the leaves of plants studied on ISS such as Arabidopsis thaliana cans also be analyzed.

  10. Mapping and Quantification of Vascular Branching in Plants, Animals and Humans by VESGEN Software

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, P. A.; Vickerman, M. B.; Keith, P. A.

    2010-01-01

    Humans face daunting challenges in the successful exploration and colonization of space, including adverse alterations in gravity and radiation. The Earth-determined biology of plants, animals and humans is significantly modified in such extraterrestrial environments. One physiological requirement shared by larger plants and animals with humans is a complex, highly branching vascular system that is dynamically responsive to cellular metabolism, immunological protection and specialized cellular/tissue function. VESsel GENeration (VESGEN) Analysis has been developed as a mature beta version, pre-release research software for mapping and quantification of the fractal-based complexity of vascular branching. Alterations in vascular branching pattern can provide informative read-outs of altered vascular regulation. Originally developed for biomedical applications in angiogenesis, VESGEN 2D has provided novel insights into the cytokine, transgenic and therapeutic regulation of angiogenesis, lymphangiogenesis and other microvascular remodeling phenomena. Vascular trees, networks and tree-network composites are mapped and quantified. Applications include disease progression from clinical ophthalmic images of the human retina; experimental regulation of vascular remodeling in the mouse retina; avian and mouse coronary vasculature, and other experimental models in vivo. We envision that altered branching in the leaves of plants studied on ISS such as Arabidopsis thaliana cans also be analyzed.

  11. Mixed vascular nevus syndrome: a report of four new cases and a literature review.

    PubMed

    Ruggieri, Martino; Polizzi, Agata; Strano, Serena; Schepis, Carmelo; Morano, Massimiliano; Belfiore, Giuseppe; Palmucci, Stefano; Foti, Pietro Valerio; Pirrone, Concetta; Sofia, Vito; David, Emanuele; Salpietro, Vincenzo; Mankad, Kshitij; Milone, Pietro

    2016-10-01

    Mixed vascular nevus (or nevus vascularis mixtus) represents an admixture of cutaneous vascular malformations of the telangiectatic type and angiospastic spots of nevus anemicus. It can occur as an purely cutaneous trait or as a hallmark of a neurocutaneous phenotype (mixed vascular nevus syndrome) characterised by the combination of: (I) paired vascular (telangiectatic and anemic) twin nevi and brain abnormalities of the Dyke-Davidoff-Masson type (i.e., crossed cerebral/cerebellar hemiatrophy with hypoplasia of the ipsilateral cerebral vessels and homolateral hypertrophy of the skull and sinuses (hyperpneumatisation) with contralateral hemispheric hypertrophy); or (II) paired vascular twin nevi and brain malformations of the Dyke-Davidoff-Masson type in association with systemic abnormalities consisting in facial asymmetry, skeletal anomalies (i.e., Legg-Calvé-Perthes-like disease) and disorders of autoimmunity (i.e., diabetes, thyroiditis). In 2014, Happle proposed to name the syndrome with the eponym Ruggieri-Leech syndrome. Review of the existing literature on nevus vascularis mixtus and information on our personal experience on new cases and follow-up of previously reported cases by some of us. The existing literature revealed 4 previous studies including 33 cases with an inferred purely cutaneous trait and 3 cases with a combination of paired vascular twin nevi and brain malformation of the Dyke-Davidoff-Masson type. Our personal experience includes 4 unpublished patients (1 female and 3 males; currently aged 2 to 34 years) seen and followed-up at our Institutions in Italy who had: paired vascular nevi involving either the face (n=2) or the face and parts of the body (n=2); facial asymmetry (n=4); mild to moderate facial dysmorphic features (n=2); developmental delay (n=3); seizures/stroke-like episodes and associated hemiplegia (n=4); muscular hypotrophy (n=2); mild to moderate hemispheric atrophy (n=4); skull osseous hypertrophy (n=4); hyperpneumatisation

  12. Effects of Disturbed Flow on Vascular Endothelium: Pathophysiological Basis and Clinical Perspectives

    PubMed Central

    Chiu, Jeng-Jiann; Chien, Shu

    2013-01-01

    Vascular endothelial cells (ECs) are exposed to hemodynamic forces, which modulate EC functions and vascular biology/pathobiology in health and disease. The flow patterns and hemodynamic forces are not uniform in the vascular system. In straight parts of the arterial tree, blood flow is generally laminar and wall shear stress is high and directed; in branches and curvatures, blood flow is disturbed with nonuniform and irregular distribution of low wall shear stress. Sustained laminar flow with high shear stress upregulates expressions of EC genes and proteins that are protective against atherosclerosis, whereas disturbed flow with associated reciprocating, low shear stress generally upregulates the EC genes and proteins that promote atherogenesis. These findings have led to the concept that the disturbed flow pattern in branch points and curvatures causes the preferential localization of atherosclerotic lesions. Disturbed flow also results in postsurgical neointimal hyperplasia and contributes to pathophysiology of clinical conditions such as in-stent restenosis, vein bypass graft failure, and transplant vasculopathy, as well as aortic valve calcification. In the venous system, disturbed flow resulting from reflux, outflow obstruction, and/or stasis leads to venous inflammation and thrombosis, and hence the development of chronic venous diseases. Understanding of the effects of disturbed flow on ECs can provide mechanistic insights into the role of complex flow patterns in pathogenesis of vascular diseases and can help to elucidate the phenotypic and functional differences between quiescent (nonatherogenic/nonthrombogenic) and activated (atherogenic/thrombogenic) ECs. This review summarizes the current knowledge on the role of disturbed flow in EC physiology and pathophysiology, as well as its clinical implications. Such information can contribute to our understanding of the etiology of lesion development in vascular niches with disturbed flow and help to generate

  13. Aortic Stenosis and Vascular Calcifications in Alkaptonuria

    PubMed Central

    Hannoush, Hwaida; Introne, Wendy J.; Chen, Marcus Y.; Lee, Sook-Jin; O'Brien, Kevin; Suwannarat, Pim; Kayser, Michael A.; Gahl, William A.; Sachdev, Vandana

    2011-01-01

    Alkaptonuria is a rare metabolic disorder of tyrosine catabolism in which homogentisic acid (HGA) accumulates and is deposited throughout the spine, large joints, cardiovascular system, and various tissues throughout the body. In the cardiovascular system, pigment deposition has been described in the heart valves, endocardium, pericardium, aortic intima and coronary arteries. The prevalence of cardiovascular disease in patients with alkaptonuria varies in previous reports . We present a series of 76 consecutive adult patients with alkaptonuria who underwent transthoracic echocardiography between 2000 and 2009. A subgroup of 40 patients enrolled in a treatment study underwent non-contrast CT scans and these were assessed for vascular calcifications. Six of the 76 patients had aortic valve replacement. In the remaining 70 patients, 12 patients had aortic sclerosis and 7 patients had aortic stenosis. Unlike degenerative aortic valve disease, we found no correlation with standard cardiac risk factors. There was a modest association between the severity of aortic valve disease and joint involvement, however, we saw no correlation with urine HGA levels. Vascular calcifications were seen in the coronaries, cardiac valves, aortic root, descending aorta and iliac arteries. These findings suggest an important role for echocardiographic screening of alkaptonuria patients to detect valvular heart disease and cardiac CT to detect coronary artery calcifications. PMID:22100375

  14. Aortic stenosis and vascular calcifications in alkaptonuria.

    PubMed

    Hannoush, Hwaida; Introne, Wendy J; Chen, Marcus Y; Lee, Sook-Jin; O'Brien, Kevin; Suwannarat, Pim; Kayser, Michael A; Gahl, William A; Sachdev, Vandana

    2012-02-01

    Alkaptonuria is a rare metabolic disorder of tyrosine catabolism in which homogentisic acid (HGA) accumulates and is deposited throughout the spine, large joints, cardiovascular system, and various tissues throughout the body. In the cardiovascular system, pigment deposition has been described in the heart valves, endocardium, pericardium, aortic intima and coronary arteries. The prevalence of cardiovascular disease in patients with alkaptonuria varies in previous reports. We present a series of 76 consecutive adult patients with alkaptonuria who underwent transthoracic echocardiography between 2000 and 2009. A subgroup of 40 patients enrolled in a treatment study underwent non-contrast CT scans and these were assessed for vascular calcifications. Six of the 76 patients had aortic valve replacement. In the remaining 70 patients, 12 patients had aortic sclerosis and 7 patients had aortic stenosis. Unlike degenerative aortic valve disease, we found no correlation with standard cardiac risk factors. There was a modest association between the severity of aortic valve disease and joint involvement, however, we saw no correlation with urine HGA levels. Vascular calcifications were seen in the coronaries, cardiac valves, aortic root, descending aorta and iliac arteries. These findings suggest an important role for echocardiographic screening of alkaptonuria patients to detect valvular heart disease and cardiac CT to detect coronary artery calcifications. Published by Elsevier Inc.

  15. Forskolin modifies retinal vascular development in Mrp4-knockout mice.

    PubMed

    Matsumiya, Wataru; Kusuhara, Sentaro; Hayashibe, Keiko; Maruyama, Kazuichi; Kusuhara, Hiroyuki; Tagami, Mizuki; Schuetz, John D; Negi, Akira

    2012-12-07

    Multidrug resistance protein 4 (MRP4) effluxes a wide variety of endogenous compounds, including cyclic adenosine monophosphate (cAMP), and is exclusively expressed in vascular endothelial cells (ECs) of the retina. This study aimed to investigate the role of MRP4 in retinal vascular development. The retinal vascular phenotype of Mrp4(-/-) mice was examined by whole-mount immunohistochemistry at P3, P6, and P14. The retinas from P6 pups that received an intraperitoneal injection of either solvent control or forskolin, an inducer of intracellular cAMP formation, at P4 and P5 were analyzed in terms of their vascular formation (vascular length, vascular branching, vascular density, and the number of tip cells), cell proliferation and apoptosis, and vessel stability. The Mrp4(-/-) mice exhibited no overt abnormalities in the development of the retinal vasculature, but retinal vascular development in the Mrp4(-/-) mice was suppressed in response to forskolin administration. There was a significant decrease in the vascular length, vascular branching, and vascular density, and inhibited tip cell formation at the vascular front. The forskolin-treated Mrp4(-/-) mice showed an increased number of Ki67-positive and cleaved caspase 3-positive ECs, a significant decrease in the amount of pericyte coverage, and a reduced number of empty sleeves. In pups exposed to hyperoxia (75% oxygen) from P7 to P12, the Mrp4(-/-) mice showed a significant increase in the unvascularized retinal area. Mrp4(-/-) mice exhibited suppressed retinal vascular development in response to forskolin treatment. Thus, Mrp4 might have protective roles in retinal vascular development by regulating the intracellular cAMP level.

  16. FGF-dependent metabolic control of vascular development

    PubMed Central

    Yu, Pengchun; Alves, Tiago C.; Fang, Jennifer S.; Xie, Yi; Zhu, Jie; Chen, Zehua; De Smet, Frederik; Zhang, Jiasheng; Jin, Suk-Won; Sun, Lele; Sun, Hongye; Kibbey, Richard G.; Hirschi, Karen K.; Hay, Nissim; Carmeliet, Peter; Chittenden, Thomas W.; Eichmann, Anne; Potente, Michael; Simons, Michael

    2017-01-01

    Blood and lymphatic vasculatures are intimately involved in tissue oxygenation and fluid homeostasis maintenance. Assembly of these vascular networks involves sprouting, migration and proliferation of endothelial cells. Recent studies have suggested that changes in cellular metabolism are of importance to these processes1. While much is known about vascular endothelial growth factor (VEGF)-dependent regulation of vascular development and metabolism2,3, little is understood about the role of fibroblast growth factors (FGFs) in this context4. Here we identify FGF receptor (FGFR) signaling as a critical regulator of vascular development. This is achieved by FGF-dependent control of c-MYC (MYC) expression that, in turn, regulates expression of the glycolytic enzyme hexokinase 2 (HK2). A decrease in HK2 levels in the absence of FGF signaling inputs results in decreased glycolysis leading to impaired endothelial cell proliferation and migration. Pan-endothelial- and lymphatic-specific Hk2 knockouts phenocopy blood and/or lymphatic vascular defects seen in Fgfr1/r3 double mutant mice while HK2 overexpression partially rescues the defects caused by suppression of FGF signaling. Thus, FGF-dependent regulation of endothelial glycolysis is a pivotal process in developmental and adult vascular growth and development. PMID:28467822

  17. Developmental regulation of vascular endothelial growth/permeability factor messenger ribonucleic acid levels in and vascularization of the villous placenta during baboon pregnancy.

    PubMed

    Hildebrandt, V A; Babischkin, J S; Koos, R D; Pepe, G J; Albrecht, E D

    2001-05-01

    Vascular endothelial growth/permeability factor (VEG/PF) has an important role in angiogenesis; however, very little is known about the developmental regulation of VEG/PF and the vascular system within the placenta during human pregnancy. In the present study, therefore, a developmental approach was used in the baboon to determine the placental source of VEG/PF and its fms-like tyrosine kinase (flt-1) and kinase-insert domain containing (KDR/flk-1) receptors, and whether the rise in estrogen with advancing pregnancy was associated with a corresponding increase in placental VEG/PF expression and vascularization. VEG/PF messenger RNA (mRNA) levels were determined by competitive RT-PCR in villous cell fractions isolated by Percoll gradient centrifugation from placentas obtained on days 45 and 54 (very early), 60 (early), 100 (mid), and 165-170 (late) of baboon pregnancy (term = 184 days). Maternal peripheral serum estradiol increased from very low concentrations early in gestation (0.15-0.20 ng/ml) to an early surge of over 2.5 ng/ml on days 60-85, and peak levels of 4-6 ng/ml late in baboon pregnancy. VEG/PF mRNA was expressed in low level in the syncytiotrophoblast (<2,000 attomol/microgram total RNA), and values in this fraction did not change significantly with advancing gestation. VEG/PF mRNA expression was slightly greater in the inner villous core cell fraction; however, levels decreased (P < 0.05) between early and late gestation. Cytotrophoblasts were a major source of VEG/PF mRNA and levels increased (P < 0.01) from 3,631 +/- 844 attomol/microgram total RNA on day 45 to 25,807 +/- 5,873 attomol/microgram total RNA on day 170. VEG/PF protein expression determined by immunocytochemistry was abundant in cytotrophoblasts and lower in the syncytiotrophoblast and inner villous core cells. The flt-1 and KDR/flk-1 receptors were expressed in the vascular endothelial cells of the baboon villous placenta. The percentage of villous placenta occupied by blood vessels

  18. Diagnosis and Treatment of Vascular Surgery Related Infection

    PubMed Central

    Zhang, Yong-Gan; Guo, Xue-Li; Song, Yan; Miao, Chao-Feng; Zhang, Chuang; Chen, Ning-Heng

    2015-01-01

    Surgical site infection (SSI) is an important component of infections acquired from hospital. The most significant feature of vascular surgery different from other surgeries is frequent application of artificial grafts. Once SSI occurs after vascular operations with grafts, it might results in a serious disaster. Staphylococcus aureus and coagulase-negative Staphylococcus are the most common pathogenic bacteria for SSI after vascular surgery. Although SSI in vascular surgery often lacks of typical clinical characters, some clinical symptoms, laboratory data and certain imaging procedures may help to diagnose. In most cases of SSI after vascular procedures, the artificial grafts must be removed and sensitive antibiotics should be administered. However, for different cases, personalized management plan should be made depending on the severity and location of SSI. PMID:26628937

  19. The SK3 channel promotes placental vascularization by enhancing secretion of angiogenic factors.

    PubMed

    Rada, Cara C; Murray, Grace; England, Sarah K

    2014-11-15

    Proper placental perfusion is essential for fetal exchange of oxygen, nutrients, and waste with the maternal circulation. Impairment of uteroplacental vascular function can lead to pregnancy complications, including preeclampsia and intrauterine growth restriction (IUGR). Potassium channels have been recognized as regulators of vascular proliferation, angiogenesis, and secretion of vasoactive factors, and their dysfunction may underlie pregnancy-related vascular diseases. Overexpression of one channel in particular, the small-conductance calcium-activated potassium channel 3 (SK3), is known to increase vascularization in mice, and mice overexpressing the SK3 channel (SK3(T/T) mice) have a high rate of fetal demise and IUGR. Here, we show that overexpression of SK3 causes fetal loss through abnormal placental vascularization. We previously reported that, at pregnancy day 14, placentas isolated from SK3(T/T) mice are smaller than those obtained from wild-type mice. In this study, histological analysis reveals that SK3(T/-) placentas at this stage have abnormal placental morphology, and microcomputed tomography shows that these placentas have significantly larger and more blood vessels than those from wild-type mice. To identify the mechanism by which these vascularization defects occur, we measured levels of vascular endothelial growth factor (VEGF), placental growth factor, and the soluble form of VEGF receptor 1 (sFlt-1), which must be tightly regulated to ensure proper placental development. Our data reveal that overexpression of SK3 alters systemic and placental ratios of the angiogenic factor VEGF to antiangiogenic factor sFlt-1 throughout pregnancy. Additionally, we observe increased expression of hypoxia-inducing factor 2α in SK3(T/-) placentas. We conclude that the SK3 channel modulates placental vascular development and fetal health by altering VEGF signaling. Copyright © 2014 the American Physiological Society.

  20. Comparison of external catheters with subcutaneous vascular access ports for chronic vascular access in a porcine model.

    PubMed

    Chuang, Marc; Orvieto, Marcelo; Laven, Brett; Gerber, Glenn; Wardrip, Craig; Ritch, Chad; Shalhav, Arieh

    2005-03-01

    We sought to compare the outcomes of two chronic vascular access techniques, the externalized catheter and the subcutaneous vascular access port, in pigs. Female farm pigs (n = 30) underwent placement of a chronic vascular access device in the jugular vein for a research protocol: 18 of the animals underwent placement of a tunneled Hickman catheter (THC), and the remaining 12 animals underwent placement of a subcutaneous vascular access port (VAP) without external components. After placement of the devices, animals underwent serial blood sampling. All animals were given identical antibiotic prophylaxis. VAP access required the use of a restraint sling for Huber needle insertion, whereas THC access required no additional equipment. Animals were euthanatized 1 month after placement of the device. In the VAP group, the port was retrieved, cleaned, and steam-autoclaved for reuse. In the THC group, 13 (72%) animals developed infectious complications, and blood and wound cultures were often polymicrobial. One animal was euthanatized secondary to overwhelming sepsis. In addition, three (17%) animals developed thromboembolic complications. In contrast, no thromboembolic complications were noted in the VAP group, and only one animal developed a transient fever which resolved spontaneously; no septic complications or abscesses developed. Blood draws with no anesthesia were successful in both groups. We conclude that subcutaneous vascular access ports are a safe and efficient method for obtaining reliable chronic vascular access for a 1-month period in pigs. The subcutaneous devices were associated with low morbidity. In contrast, externalized catheters can be associated with considerable morbidity.

  1. Multifunctional silk-heparin biomaterials for vascular tissue engineering applications

    PubMed Central

    Seib, F. Philipp; Herklotz, Manuela; Burke, Kelly A.; Maitz, Manfred F.; Werner, Carsten; Kaplan, David L.

    2013-01-01

    Over the past 30 years, silk has been proposed for numerous biomedical applications that go beyond its traditional use as a suture material. Silk sutures are well tolerated in humans, but the use of silk for vascular engineering applications still requires extensive biocompatibility testing. Some studies have indicated a need to modify silk to yield a hemocompatible surface. This study examined the potential of low molecular weight heparin as a material for refining silk properties by acting as a carrier for vascular endothelial growth factor (VEGF) and improving silk hemocompatibility. Heparinized silk showed a controlled VEGF release over 6 days; the released VEGF was bioactive and supported the growth of human endothelial cells. Silk samples were then assessed using a humanized hemocompatibility system that employs whole blood and endothelial cells. The overall thrombogenic response for silk was very low and similar to the clinical reference material polytetrafluoroethylene. Despite an initial inflammatory response to silk, apparent as complement and leukocyte activation, the endothelium was maintained in a resting, anticoagulant state. The low thrombogenic response and the ability to control VEGF release support the further development of silk for vascular applications. PMID:24099708

  2. Vascular rarefaction mediates whitening of brown fat in obesity

    PubMed Central

    Shimizu, Ippei; Aprahamian, Tamar; Kikuchi, Ryosuke; Shimizu, Ayako; Papanicolaou, Kyriakos N.; MacLauchlan, Susan; Maruyama, Sonomi; Walsh, Kenneth

    2014-01-01

    Brown adipose tissue (BAT) is a highly vascularized organ with abundant mitochondria that produce heat through uncoupled respiration. Obesity is associated with a reduction of BAT function; however, it is unknown how obesity promotes dysfunctional BAT. Here, using a murine model of diet-induced obesity, we determined that obesity causes capillary rarefaction and functional hypoxia in BAT, leading to a BAT “whitening” phenotype that is characterized by mitochondrial dysfunction, lipid droplet accumulation, and decreased expression of Vegfa. Targeted deletion of Vegfa in adipose tissue of nonobese mice resulted in BAT whitening, supporting a role for decreased vascularity in obesity-associated BAT. Conversely, introduction of VEGF-A specifically into BAT of obese mice restored vascularity, ameliorated brown adipocyte dysfunction, and improved insulin sensitivity. The capillary rarefaction in BAT that was brought about by obesity or Vegfa ablation diminished β-adrenergic signaling, increased mitochondrial ROS production, and promoted mitophagy. These data indicate that overnutrition leads to the development of a hypoxic state in BAT, causing it to whiten through mitochondrial dysfunction and loss. Furthermore, these results link obesity-associated BAT whitening to impaired systemic glucose metabolism. PMID:24713652

  3. Precise correlation of histopathological and fluorescein angiographic morphology using retinal vascular casting.

    PubMed

    Bek, T; Prause, J U

    1996-12-01

    The histopathology of three eyes obtained post mortem from 2 patients with age-related macular degeneration was correlated with the pre mortem fluorescein angiographic morphology. A precise point-by-point correlation between histopathology and the corresponding angiographic appearance was ensured by using the cast retinal vascular system as a pattern of reference. The study showed that both the photoreceptors, the pigment epithelium, and substances accumulated between the retinal and the choroidal vascular systems, may have a blocking effect on choroidal background fluorescence as seen on fluorescein angiograms. Furthermore, it is confirmed that fluorescein angiographic hyperfluorescence may be due to a lack of blocking of the choroidal fluorescence because of a window defect in the retinal photoreceptor layer and/or the pigment epithelium.

  4. Epithelioid Hemangioendothelioma: A Rare Vascular Tumor

    PubMed Central

    Lakshmi, S Vidya; Prabhavathy, D; Jayakumar, S; Janaki, C; Tharini, G K

    2012-01-01

    Epithelioid hemangioendothelioma is an intermediate-grade vascular tumor arising from the vascular endothelium, which usually arises in soft tissue, and skin involvement is extremely rare. We report a case that presented with primary cutaneous tumor involving the whole limb and was present since birth. PMID:22470212

  5. Hemodynamics and Vascular Hypertrophy in African Americans and Caucasians With High Blood Pressure.

    PubMed

    Hill, LaBarron K; Sherwood, Andrew; Blumenthal, James A; Hinderliter, Alan L

    2016-12-01

    Hypertension in African Americans is characterized by greater systemic vascular resistance (SVR) compared with Caucasian Americans, but the responsible mechanisms are not known. The present study sought to determine if peripheral vascular hypertrophy is a potential mechanism contributing to elevated SVR in African Americans with high blood pressure (BP). In a biracial sample of 80 men and women between the ages of 25 and 45 years, with clinic BP in the range 130/85-160/99mm Hg, we assessed cardiac output and SVR, in addition to BP. Minimum forearm vascular resistance (MFVR), a marker of vascular hypertrophy, also was assessed. SVR was elevated in African Americans compared with Caucasians (P < 0.001). Regression models indicated that age, body mass index, 24-hour diastolic BP, and ethnicity were significant predictors of SVR. There was also a significant interaction between ethnicity and MFVR in explaining SVR in the study sample. In particular, there was a significant positive association between MFVR and SVR among African Americans (P = 0.002), whereas the association was inverse and not statistically significant among Caucasians (P = 0.601). Hypertrophy of the systemic microvasculature may contribute to the elevated SVR that is characteristic of the early stages of hypertension in African American compared with Caucasians. © American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  6. A first vascularized skin equivalent as an alternative to animal experimentation.

    PubMed

    Groeber, Florian; Engelhardt, Lisa; Lange, Julia; Kurdyn, Szymon; Schmid, Freia F; Rücker, Christoph; Mielke, Stephan; Walles, Heike; Hansmann, Jan

    2016-01-01

    Tissue-engineered skin equivalents mimic key aspects of the human skin, and can thus be employed as wound coverage for large skin defects or as in vitro test systems as an alternative to animal models. However, current skin equivalents lack a functional vasculature limiting clinical and research applications. This study demonstrates the generation of a vascularized skin equivalent with a perfused vascular network by combining a biological vascularized scaffold (BioVaSc) based on a decellularized segment of a porcine jejunum and a tailored bioreactor system. Briefly, the BioVaSc was seeded with human fibroblasts, keratinocytes, and human microvascular endothelial cells. After 14 days at the air-liquid interface, hematoxylin & eosin and immunohistological staining revealed a specific histological architecture representative of the human dermis and epidermis including a papillary-like architecture at the dermal-epidermal-junction. The formation of the skin barrier was measured non-destructively using impedance spectroscopy. Additionally, endothelial cells lined the walls of the formed vessels that could be perfused with a physiological volume flow. Due to the presence of a complex in-vivo-like vasculature, the here shown skin equivalent has the potential for skin grafting and represents a sophisticated in vitro model for dermatological research.

  7. Forskolin Modifies Retinal Vascular Development in Mrp4-Knockout Mice

    PubMed Central

    Matsumiya, Wataru; Kusuhara, Sentaro; Hayashibe, Keiko; Maruyama, Kazuichi; Kusuhara, Hiroyuki; Tagami, Mizuki; Schuetz, John D.; Negi, Akira

    2012-01-01

    Purpose. Multidrug resistance protein 4 (MRP4) effluxes a wide variety of endogenous compounds, including cyclic adenosine monophosphate (cAMP), and is exclusively expressed in vascular endothelial cells (ECs) of the retina. This study aimed to investigate the role of MRP4 in retinal vascular development. Methods. The retinal vascular phenotype of Mrp4−/− mice was examined by whole-mount immunohistochemistry at P3, P6, and P14. The retinas from P6 pups that received an intraperitoneal injection of either solvent control or forskolin, an inducer of intracellular cAMP formation, at P4 and P5 were analyzed in terms of their vascular formation (vascular length, vascular branching, vascular density, and the number of tip cells), cell proliferation and apoptosis, and vessel stability. Results. The Mrp4−/− mice exhibited no overt abnormalities in the development of the retinal vasculature, but retinal vascular development in the Mrp4−/− mice was suppressed in response to forskolin administration. There was a significant decrease in the vascular length, vascular branching, and vascular density, and inhibited tip cell formation at the vascular front. The forskolin-treated Mrp4−/− mice showed an increased number of Ki67-positive and cleaved caspase 3–positive ECs, a significant decrease in the amount of pericyte coverage, and a reduced number of empty sleeves. In pups exposed to hyperoxia (75% oxygen) from P7 to P12, the Mrp4−/− mice showed a significant increase in the unvascularized retinal area. Conclusions. Mrp4−/− mice exhibited suppressed retinal vascular development in response to forskolin treatment. Thus, Mrp4 might have protective roles in retinal vascular development by regulating the intracellular cAMP level. PMID:23154460

  8. Skin integrated with perfusable vascular channels on a chip.

    PubMed

    Mori, Nobuhito; Morimoto, Yuya; Takeuchi, Shoji

    2017-02-01

    This paper describes a method for fabricating perfusable vascular channels coated with endothelial cells within a cultured skin-equivalent by fixing it to a culture device connected to an external pump and tubes. A histological analysis showed that vascular channels were constructed in the skin-equivalent, which showed a conventional dermal/epidermal morphology, and the endothelial cells formed tight junctions on the vascular channel wall. The barrier function of the skin-equivalent was also confirmed. Cell distribution analysis indicated that the vascular channels supplied nutrition to the skin-equivalent. Moreover, the feasibility of a skin-equivalent containing vascular channels as a model for studying vascular absorption was demonstrated by measuring test molecule permeation from the epidermal layer into the vascular channels. The results suggested that this skin-equivalent can be used for skin-on-a-chip applications including drug development, cosmetics testing, and studying skin biology. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Drinking citrus fruit juice inhibits vascular remodeling in cuff-induced vascular injury mouse model.

    PubMed

    Ohnishi, Arika; Asayama, Rie; Mogi, Masaki; Nakaoka, Hirotomo; Kan-No, Harumi; Tsukuda, Kana; Chisaka, Toshiyuki; Wang, Xiao-Li; Bai, Hui-Yu; Shan, Bao-Shuai; Kukida, Masayoshi; Iwanami, Jun; Horiuchi, Masatsugu

    2015-01-01

    Citrus fruits are thought to have inhibitory effects on oxidative stress, thereby attenuating the onset and progression of cancer and cardiovascular disease; however, there are few reports assessing their effect on vascular remodeling. Here, we investigated the effect of drinking the juice of two different citrus fruits on vascular neointima formation using a cuff-induced vascular injury mouse model. Male C57BL6 mice were divided into five groups as follows: 1) Control (water) (C), 2) 10% Citrus unshiu (CU) juice (CU10), 3) 40% CU juice (CU40), 4) 10% Citrus iyo (CI) juice (CI10), and 5) 40% CI juice (CI40). After drinking them for 2 weeks from 8 weeks of age, cuff injury was induced by polyethylene cuff placement around the femoral artery. Neointima formation was significantly attenuated in CU40, CI10 and CI40 compared with C; however, no remarkable preventive effect was observed in CU10. The increases in levels of various inflammatory markers including cytokines such as monocyte chemotactic protein-1, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in response to vascular injury did not differ significantly between C, CU10 and CI10. The increases in cell proliferation and superoxide anion production were markedly attenuated in CI10, but not in CU10 compared with C. The increase in phosphorylated ERK expression was markedly attenuated both in CU10 and CI10 without significant difference between CU10 and CI10. Accumulation of immune cells did not differ between CU10 and CI10. These results indicate that drinking citrus fruit juice attenuates vascular remodeling partly via a reduction of oxidative stress. Interestingly, the preventive efficacy on neointima formation was stronger in CI than in CU at least in part due to more prominent inhibitory effects on oxidative stress by CI.

  10. Drinking Citrus Fruit Juice Inhibits Vascular Remodeling in Cuff-Induced Vascular Injury Mouse Model

    PubMed Central

    Ohnishi, Arika; Asayama, Rie; Mogi, Masaki; Nakaoka, Hirotomo; Kan-no, Harumi; Tsukuda, Kana; Chisaka, Toshiyuki; Wang, Xiao-Li; Bai, Hui-Yu; Shan, Bao-Shuai; Kukida, Masayoshi; Iwanami, Jun; Horiuchi, Masatsugu

    2015-01-01

    Citrus fruits are thought to have inhibitory effects on oxidative stress, thereby attenuating the onset and progression of cancer and cardiovascular disease; however, there are few reports assessing their effect on vascular remodeling. Here, we investigated the effect of drinking the juice of two different citrus fruits on vascular neointima formation using a cuff-induced vascular injury mouse model. Male C57BL6 mice were divided into five groups as follows: 1) Control (water) (C), 2) 10% Citrus unshiu (CU) juice (CU10), 3) 40% CU juice (CU40), 4) 10% Citrus iyo (CI) juice (CI10), and 5) 40% CI juice (CI40). After drinking them for 2 weeks from 8 weeks of age, cuff injury was induced by polyethylene cuff placement around the femoral artery. Neointima formation was significantly attenuated in CU40, CI10 and CI40 compared with C; however, no remarkable preventive effect was observed in CU10. The increases in levels of various inflammatory markers including cytokines such as monocyte chemotactic protein-1, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in response to vascular injury did not differ significantly between C, CU10 and CI10. The increases in cell proliferation and superoxide anion production were markedly attenuated in CI10, but not in CU10 compared with C. The increase in phosphorylated ERK expression was markedly attenuated both in CU10 and CI10 without significant difference between CU10 and CI10. Accumulation of immune cells did not differ between CU10 and CI10. These results indicate that drinking citrus fruit juice attenuates vascular remodeling partly via a reduction of oxidative stress. Interestingly, the preventive efficacy on neointima formation was stronger in CI than in CU at least in part due to more prominent inhibitory effects on oxidative stress by CI. PMID:25692290

  11. Differential roles of NADPH oxidases in vascular physiology and pathophysiology

    PubMed Central

    Amanso, Angelica M.; Griendling, Kathy K.

    2012-01-01

    Reactive oxygen species (ROS) are produced by all vascular cells and regulate the major physiological functions of the vasculature. Production and removal of ROS are tightly controlled and occur in discrete subcellular locations, allowing for specific, compartmentalized signaling. Among the many sources of ROS in the vessel wall, NADPH oxidases are implicated in physiological functions such as control of vasomotor tone, regulation of extracellular matrix and phenotypic modulation of vascular smooth muscle cells. They are involved in the response to injury, whether as an oxygen sensor during hypoxia, as a regulator of protein processing, as an angiogenic stimulus, or as a mechanism of wound healing. These enzymes have also been linked to processes leading to disease development, including migration, proliferation, hypertrophy, apoptosis and autophagy. As a result, NADPH oxidases participate in atherogenesis, systemic and pulmonary hypertension and diabetic vascular disease. The role of ROS in each of these processes and diseases is complex, and a more full understanding of the sources, targets, cell-specific responses and counterbalancing mechanisms is critical for the rational development of future therapeutics. PMID:22202108

  12. IR imaging of blood circulation of patients with vascular disease

    NASA Astrophysics Data System (ADS)

    Wang, Hsin; Wade, Dwight R., Jr.; Kam, Jack

    2004-04-01

    We conducted a preliminary IR imaging study of blood circulation in patients with peripheral vascular diseases. Abnormal blood flow is common in older adults, especially those with elevated blood lipids, diabetes, hypertension, and a history of smoking. All of these conditions have a high prevalence in our population, often with more than one condition in the same individual. The differences in blood flow is revealed by temperature differences in areas of the extremities as well as other regions of the body. However, what is needed is an imaging technique that is relatively inexpensive and can reveal the blood flow in real time. The IR imaging can show detailed venous system and small tempearture changes associated with blood flow. Six patients with vascular diseases were tested in a clinic set up. Their legs and feet were imaged. We observed large temperature differences (cooling of more than 10° C) at the foot, especially toes. More valuable information were obtained from the temperature distribution maps. IR thermography is potentially a very valuable tool for medical application, especially for vascular diseases.

  13. Modulation of 11β-hydroxysteroid dehydrogenase as a strategy to reduce vascular inflammation.

    PubMed

    Hadoke, Patrick W F; Kipari, Tiina; Seckl, Jonathan R; Chapman, Karen E

    2013-05-01

    Atherosclerosis is a chronic inflammatory disease in which initial vascular damage leads to extensive macrophage and lymphocyte infiltration. Although acutely glucocorticoids suppress inflammation, chronic glucocorticoid excess worsens atherosclerosis, possibly by exacerbating systemic cardiovascular risk factors. However, glucocorticoid action within the lesion may reduce neointimal proliferation and inflammation. Glucocorticoid levels within cells do not necessarily reflect circulating levels due to pre-receptor metabolism by 11β-hydroxysteroid dehydrogenases (11β-HSDs). 11β-HSD2 converts active glucocorticoids into inert 11-keto forms. 11β-HSD1 catalyses the reverse reaction, regenerating active glucocorticoids. 11β-HSD2-deficiency/inhibition causes hypertension, whereas deficiency/inhibition of 11β-HSD1 generates a cardioprotective lipid profile and improves glycemic control. Importantly, 11β-HSD1-deficiency/inhibition is atheroprotective, whereas 11β-HSD2-deficiency accelerates atherosclerosis. These effects are largely independent of systemic risk factors, reflecting modulation of glucocorticoid action and inflammation within the vasculature. Here, we consider whether evidence linking the 11β-HSDs to vascular inflammation suggests these isozymes are potential therapeutic targets in vascular injury and atherosclerosis.

  14. 3D Printed Vascular Networks Enhance Viability in High-Volume Perfusion Bioreactor.

    PubMed

    Ball, Owen; Nguyen, Bao-Ngoc B; Placone, Jesse K; Fisher, John P

    2016-12-01

    There is a significant clinical need for engineered bone graft substitutes that can quickly, effectively, and safely repair large segmental bone defects. One emerging field of interest involves the growth of engineered bone tissue in vitro within bioreactors, the most promising of which are perfusion bioreactors. Using bioreactor systems, tissue engineered bone constructs can be fabricated in vitro. However, these engineered constructs lack inherent vasculature and once implanted, quickly develop a necrotic core, where no nutrient exchange occurs. Here, we utilized COMSOL modeling to predict oxygen diffusion gradients throughout aggregated alginate constructs, which allowed for the computer-aided design of printable vascular networks, compatible with any large tissue engineered construct cultured in a perfusion bioreactor. We investigated the effect of 3D printed macroscale vascular networks with various porosities on the viability of human mesenchymal stem cells in vitro, using both gas-permeable, and non-gas permeable bioreactor growth chamber walls. Through the use of 3D printed vascular structures in conjunction with a tubular perfusion system bioreactor, cell viability was found to increase by as much as 50% in the core of these constructs, with in silico modeling predicting construct viability at steady state.

  15. 3D Printed Vascular Networks Enhance Viability in High-Volume Perfusion Bioreactor

    PubMed Central

    Ball, Owen; Nguyen, Bao-Ngoc B.; Placone, Jesse K.; Fisher, John P.

    2016-01-01

    There is a significant clinical need for engineered bone graft substitutes that can quickly, effectively, and safely repair large segmental bone defects. One emerging field of interest involves the growth of engineered bone tissue in vitro within bioreactors, the most promising of which are perfusion bioreactors. Using bioreactor systems, tissue engineered bone constructs can be fabricated in vitro. However, these engineered constructs lack inherent vasculature and once implanted, quickly develop a necrotic core, where no nutrient exchange occurs. Here, we utilized COMSOL modeling to predict oxygen diffusion gradients throughout aggregated alginate constructs, which allowed for the computer-aided design of printable vascular networks, compatible with any large tissue engineered construct cultured in a perfusion bioreactor. We investigated the effect of 3D printed macroscale vascular networks with various porosities on the viability of human mesenchymal stem cells in vitro, using both gas-permeable, and non-gas permeable bioreactor growth chamber walls. Through the use of 3D printed vascular structures in conjunction with a tubular perfusion system bioreactor, cell viability was found to increase by as much as 50% in the core of these constructs, with in silico modeling predicting construct viability at steady state. PMID:27272210

  16. Detection of vascularity in wrist tenosynovitis: power doppler ultrasound compared with contrast-enhanced grey-scale ultrasound.

    PubMed

    Klauser, Andrea S; Franz, Magdalena; Arora, Rohit; Feuchtner, Gudrun M; Gruber, Johann; Schirmer, Michael; Jaschke, Werner R; Gabl, Markus F

    2010-01-01

    We sought to assess vascularity in wrist tenosynovitis by using power Doppler ultrasound (PDUS) and to compare detection of intra- and peritendinous vascularity with that of contrast-enhanced grey-scale ultrasound (CEUS). Twenty-six tendons of 24 patients (nine men, 15 women; mean age ± SD, 54.4 ± 11.8 years) with a clinical diagnosis of tenosynovitis were examined with B-mode ultrasonography, PDUS, and CEUS by using a second-generation contrast agent, SonoVue (Bracco Diagnostics, Milan, Italy) and a low-mechanical-index ultrasound technique. Thickness of synovitis, extent of vascularized pannus, intensity of peritendinous vascularisation, and detection of intratendinous vessels was incorporated in a 3-score grading system (grade 0 to 2). Interobserver variability was calculated. With CEUS, a significantly greater extent of vascularity could be detected than by using PDUS (P < 0.001). In terms of peri- and intratendinous vessels, CEUS was significantly more sensitive in the detection of vascularization compared with PDUS (P < 0.001). No significant correlation between synovial thickening and extent of vascularity could be found (P = 0.089 to 0.097). Interobserver reliability was calculated to be excellent when evaluating the grading score (κ = 0.811 to 1.00). CEUS is a promising tool to detect tendon vascularity with higher sensitivity than PDUS by improved detection of intra- and peritendinous vascularity.

  17. Neutrophil subsets and their gene signature associate with vascular inflammation and coronary atherosclerosis in lupus

    PubMed Central

    Carlucci, Philip M.; Purmalek, Monica M.; Dey, Amit K.; Temesgen-Oyelakin, Yenealem; Sakhardande, Simantini; Joshi, Aditya A.; Lerman, Joseph B.; Fike, Alice; Davis, Michael; Chung, Jonathan H.; Playford, Martin P.; Naqi, Mohammad; Mistry, Pragnesh; Gutierrez-Cruz, Gustavo; Dell’Orso, Stefania; Naz, Faiza; Salahuddin, Taufiq; Natarajan, Balaji; Tsai, Wanxia L.; Gupta, Sarthak; Grayson, Peter; Chen, Marcus Y.; Sun, Hong-Wei; Hasni, Sarfaraz; Mehta, Nehal N.

    2018-01-01

    BACKGROUND. Systemic lupus erythematosus (SLE) is associated with enhanced risk of atherosclerotic cardiovascular disease not explained by Framingham risk score (FRS). Immune dysregulation associated to a distinct subset of lupus proinflammatory neutrophils (low density granulocytes; LDGs) may play key roles in conferring enhanced CV risk. This study assessed if lupus LDGs are associated with in vivo vascular dysfunction and inflammation and coronary plaque. METHODS. SLE subjects and healthy controls underwent multimodal phenotyping of vascular disease by quantifying vascular inflammation (18F-fluorodeoxyglucose–PET/CT [18F-FDG–PET/CT]), arterial dysfunction (EndoPAT and cardio-ankle vascular index), and coronary plaque burden (coronary CT angiography). LDGs were quantified by flow cytometry. Cholesterol efflux capacity was measured in high-density lipoprotein–exposed (HDL-exposed) radioactively labeled cell lines. Whole blood RNA sequencing was performed to assess associations between transcriptomic profiles and vascular phenotype. RESULTS. Vascular inflammation, arterial stiffness, and noncalcified plaque burden (NCB) were increased in SLE compared with controls even after adjustment for traditional risk factors. In SLE, NCB directly associated with LDGs and associated negatively with cholesterol efflux capacity in fully adjusted models. A neutrophil gene signature reflective of the most upregulated genes in lupus LDGs associated with vascular inflammation and NCB. CONCLUSION. Individuals with SLE demonstrate vascular inflammation, arterial dysfunction, and NCB, which may explain the higher reported risk for acute coronary syndromes. The association of LDGs and neutrophil genes with vascular disease supports the hypothesis that distinct neutrophil subsets contribute to vascular damage and unstable coronary plaque in SLE. Results also support previous observations that neutrophils may disrupt HDL function and thereby promote atherogenesis. TRIAL REGISTRATION

  18. Longitudinal visualization of vascular occlusion, reperfusion, and remodeling in a zebrafish model of retinal vascular leakage using OCT angiography

    NASA Astrophysics Data System (ADS)

    Spitz, Kathleen; Bozic, Ivan; Desai, Vineet; Rao, Gopikrishna M.; Pollock, Lana M.; Anand-Apte, Bela; Tao, Yuankai K.

    2017-02-01

    Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are two of the leading causes of blindness and visual impairment in the world. Neovascularization results in severe vision loss in DR and AMD and, thus, there is an unmet need to identify mechanisms of pathogenesis and novel anti-angiogenic therapies. Zebrafish is a leading model organism for studying human disease pathogenesis, and the highly conserved drug activity between zebrafish and humans and their ability to readily absorb small molecules dissolved in water has benefited pharmaceutical discovery. Here, we use optical coherence tomography (OCT) and OCT angiography (OCT-A) to perform noninvasive, in vivo retinal imaging in a zebrafish model of vascular leakage. Zebrafish were treated with diethylaminobenzaldehyde (DEAB) to induce vascular leakage and imaged with OCT and OCT-A at six time points over two weeks: baseline one day before treatment and one, three, six, eight, and ten days post treatment. Longitudinal functional imaging showed significant vascular response immediately after DEAB treatment. Observed vascular changes included partial or complete vascular occlusion immediately after treatment and reperfusion during a two-week period. Increased vascular tortuosity several days post treatment indicated remodeling, and bifurcations and collateral vessel formation were also observed. In addition, significant treatment response variabilities were observed in the contralateral eye of the same animal. Anatomical and functional normalization was observed in most animals by ten days post treatment. These preliminary results motivate potential applications of OCT-A as a tool for studying pathogenesis and therapeutic screening in zebrafish models of retinal vascular disease.

  19. Diagnostic criteria for vascular cognitive disorders: a VASCOG statement

    PubMed Central

    Sachdev, Perminder; Kalaria, Raj; O’Brien, John; Skoog, Ingmar; Alladi, Suvarna; Black, Sandra E; Blacker, Deborah; Blazer, Dan; Chen, Christopher; Chui, Helena; Ganguli, Mary; Jellinger, Kurt; Jeste, Dilip V.; Pasquier, Florence; Paulsen, Jane; Prins, Niels; Rockwood, Kenneth; Roman, Gustavo; Scheltens, Philip

    2014-01-01

    Background Several sets of diagnostic criteria have been published for vascular dementia (VaD) since the 1960s. The continuing ambiguity in VaD definition warrants a critical re-examination. Methods Participants at a special symposium of the International Society for Vascular Behavioral and Cognitive Disorders (VASCOG) in 2009 critiqued the current criteria. They drafted a proposal for a new set of criteria, later reviewed through multiple drafts by the group, including additional experts and the members of the Neurocognitive Disorders Work Group of the DSM-5 Task Force. Results Cognitive disorders of vascular etiology are a heterogeneous group of disorders with diverse pathologies and clinical manifestations, discussed broadly under the rubric of vascular cognitive disorders (VCD). The continuum of vascular cognitive impairment is recognized by the categories of Mild Vascular Cognitive Disorder, and Vascular Dementia or Major Vascular Cognitive Disorder. Diagnostic thresholds are defined. Clinical and neuroimaging criteria are proposed for establishing vascular etiology. Subtypes of VCD are described, and the frequent co-occurrence of Alzheimer’s disease pathology emphasized. Conclusions The proposed criteria for VCD provide a coherent approach to the diagnosis of this diverse group of disorders, with a view to stimulating clinical and pathological validation studies. These criteria can be harmonized with the DSM-5 criteria such that an international consensus on the criteria for VCD may be achieved. PMID:24632990

  20. Virtual-Reality Simulator System for Double Interventional Cardiac Catheterization Using Fractional-Order Vascular Access Tracker and Haptic Force Producer

    PubMed Central

    Chen, Guan-Chun; Lin, Chia-Hung; Hsieh, Kai-Sheng; Du, Yi-Chun; Chen, Tainsong

    2015-01-01

    This study proposes virtual-reality (VR) simulator system for double interventional cardiac catheterization (ICC) using fractional-order vascular access tracker and haptic force producer. An endoscope or a catheter for diagnosis and surgery of cardiovascular disease has been commonly used in minimally invasive surgery. It needs specific skills and experiences for young surgeons or postgraduate year (PGY) students to operate a Berman catheter and a pigtail catheter in the inside of the human body and requires avoiding damaging vessels. To improve the training in inserting catheters, a double-catheter mechanism is designed for the ICC procedures. A fractional-order vascular access tracker is used to trace the senior surgeons' consoled trajectories and transmit the frictional feedback and visual feedback during the insertion of catheters. Based on the clinical feeling through the aortic arch, vein into the ventricle, or tortuous blood vessels, haptic force producer is used to mock the elasticity of the vessel wall using voice coil motors (VCMs). The VR establishment with surgeons' consoled vessel trajectories and hand feeling is achieved, and the experimental results show the effectiveness for the double ICC procedures. PMID:26171419

  1. Regionalization of services improves access to emergency vascular surgical care.

    PubMed

    Roche-Nagle, G; Bachynski, K; Nathens, A B; Angoulvant, D; Rubin, B B

    2013-04-01

    Management of vascular surgical emergencies requires rapid access to a vascular surgeon and hospital with the infrastructure necessary to manage vascular emergencies. The purpose of this study was to assess the impact of regionalization of vascular surgery services in Toronto to University Health Network (UHN) and St Michael's Hospital (SMH) on the ability of CritiCall Ontario to transfer patients with life- and limb-threatening vascular emergencies for definitive care. A retrospective review of the CritiCall Ontario database was used to assess the outcome of all calls to CritiCall regarding patients with vascular disease from April 2003 to March 2010. The number of patients with vascular emergencies referred via CritiCall and accepted in transfer by the vascular centers at UHN or SMH increased 500% between 1 April 2003-31 December 2005 and 1 January 2006-31 March 2010. Together, the vascular centers at UHN and SMH accepted 94.8% of the 1002 vascular surgery patients referred via CritiCall from other hospitals between 1 January 2006 and 31 March 2010, and 72% of these patients originated in hospitals outside of the Toronto Central Local Health Integration Network. Across Ontario, the number of physicians contacted before a patient was accepted in transfer fell from 2.9 ± 0.4 before to 1.7 ± 0.3 after the vascular centers opened. In conclusion, the vascular surgery centers at UHN and SMH have become provincial resources that enable the efficient transfer of patients with vascular surgical emergencies from across Ontario. Regionalization of services is a viable model to increase access to emergent care.

  2. Vascular dysfunction in women with a history of preeclampsia and intrauterine growth restriction: insights into future vascular risk.

    PubMed

    Yinon, Yoav; Kingdom, John C P; Odutayo, Ayodele; Moineddin, Rahim; Drewlo, Sascha; Lai, Vesta; Cherney, David Z I; Hladunewich, Michelle A

    2010-11-02

    Women with a history of placental disease are at increased risk for the future development of vascular disease. It is unknown whether preexisting endothelial dysfunction underlies both the predisposition to placental disease and the later development of vascular disease. The aim of this study was to assess vascular function in postpartum women and to determine whether differences emerged depending on the presentation of placental disease. Women with a history of early-onset preeclampsia (n=15), late-onset preeclampsia (n=9), intrauterine growth restriction without preeclampsia (n=9), and prior normal pregnancy (n=16) were studied 6 to 24 months postpartum. Flow-mediated vasodilatation and flow-independent (glyceryl trinitrate-induced) vasodilatation were studied through the use of high-resolution vascular ultrasound examination of the brachial artery. Arterial stiffness was assessed by pulse-wave analysis (augmentation index). Laboratory assessment included circulating angiogenic factors (vascular endothelial growth factor, soluble fms-like tyrosine kinase 1, placental growth factor, and soluble endoglin). Flow-mediated vasodilatation was significantly reduced in women with previous early-onset preeclampsia and intrauterine growth restriction compared with women with previous late-onset preeclampsia and control subjects (3.2±2.7% and 2.1±1.2% versus 7.9±3.8% and 9.1±3.5%, respectively; P<0.0001). Flow-independent vasodilatation was similar among all groups. Similarly, the radial augmentation index was significantly increased among women with previous early-onset preeclampsia and intrauterine growth restriction, but not among late preeclamptic women and control subjects (P=0.0105). Circulating angiogenic factors were similar in all groups. Only women with a history of early-onset preeclampsia or intrauterine growth restriction without preeclampsia exhibit impaired vascular function, which might explain their predisposition to placental disease and their higher

  3. Ghrelin attenuates vascular calcification in diabetic patients with amputation.

    PubMed

    Xu, Suining; Ye, Fei; Li, Lihua; Yan, Jinchuan; Bao, Zhengyang; Sun, Zhen; Xu, Liangjie; Zhu, Jie; Wang, Zhongqun

    2017-07-01

    Vascular calcification is established to be a critical factor in diabetes mellitus, which causes cardiovascular and amputation complication of diabetic patients. OPG/RANKL/RANK axis serves as a regulatory role in vascular calcification. Ghrelin, an endogenous ligand of growth hormone secretagogue receptor (GHSR), has been reported to exhibit potent cardiovascular protective effects. However, the role of ghrelin in the regulation of diabetic vascular calcification is still elusive. Here, we reported the role of ghrelin and its relationship with OPG/RANKL/RANK system in patients with diabetic foot amputation. In vivo and in vitro investigations were performed. Sixty type 2 diabetic patients with foot amputation were enrolled in vivo investigation, and they were divided into three groups through Doppler ultrasound: mild stenosis group (n=20), moderate stenosis group (n=20), and severe stenosis/occlusion group (n=20). Morphological analysis results showed diffused calcium depositions in the anterior tibial artery of diabetic amputees. Compared with the mild and moderate stenosis group, the severe stenosis/occlusion group had more spotty calcium depositions in atherosclerotic plaques. Western blot analysis indicated the expressions of osteoprotegerin (OPG) and ghrelin were downregulated, while the expression of receptor activator of nuclear factor kappa B ligand (RANKL) was upregulated with the vascular stenosis aggravation. Pearson correlation analysis revealed a negative correlation between calcium content and ghrelin levels (r=-0.58, P<0.001), as well as the ghrelin levels and sRANKL levels (r=-0.57, P<0.001). Meanwhile, OPG levels were positively correlated with ghrelin levels (r=0.63, P<0.001). From in vitro investigation, we found that the high-glucose (HG), high-lipid (HL), and β-glycerophosphate (β-GP) considerably increased the total calcium content, ALP activity, and expression of osteogenic markers in vascular smooth muscle cells (VSMCs). Ghrelin blunted

  4. Vascular tumors of the iris in 45 patients: the 2009 Helen Keller Lecture.

    PubMed

    Shields, Jerry A; Bianciotto, Carlos; Kligman, Brad E; Shields, Carol L

    2010-09-01

    To report on a series of vascular tumors of the iris. Noncomparative case series. A retrospective medical record review of all patients with an iris vascular tumor was performed to identify the clinical features and develop a simple classification of these lesions. Included were demographics, clinical features, systemic associations, complications, management, and histopathology. There were 54 eyes in 45 patients with an iris vascular tumor. These were categorized as racemose hemangioma (41 eyes: 29 simple and 12 complex), cavernous hemangioma (3 eyes: 2 localized and 1 systemic), capillary hemangioma (1 eye, localized), varix (3 eyes, localized), and microhemangiomatosis (6 eyes, localized). The hemangiomas occurred in adults at a median age of 55 years, whereas capillary hemangioma occurred in infancy and cavernous hemangioma with systemic involvement occurred in a child. Of the 41 eyes with iris racemose hemangioma, none showed systemic involvement. Of all 54 eyes, transient hyphema was the main complication, found at some point in 30% or more of each affected eye except for iris capillary and racemose hemangioma. Surgical resection was necessary in 1 cavernous hemangioma and 1 varix. The remainder were managed with observation. There are now well-documented examples of iris racemose hemangioma, cavernous hemangioma, capillary hemangioma, varix, and microhemangiomatosis. Transient hyphema is the main complication. Observation is usually advised. Most are solitary lesions confined to the iris and some (cavernous hemangioma and microhemangiomatosis) can have important systemic associations.

  5. Cues for cellular assembly of vascular elastin networks

    NASA Astrophysics Data System (ADS)

    Kothapalli, Chandrasekhar R.

    LOX protein synthesis (2.5-fold); these cues also enhanced deposition of mature elastic fibers (˜1 mum diameter) within these cultures. Interestingly, instead of copper salt addition, even release of Cu 2+ ions (˜0.1 M) from copper nanoparticles (400 ng/mL), concurrent with HA oligomers, promoted crosslinking of elastin into mature matrix, with multiple bundles of highly-crosslinked elastin fiber formation observed (diameter ˜200-500 nm). These results strongly attest to the potential individual and combined benefits of these cues to faithful elastin matrix regeneration by healthy, patient-derived cells within tissue-engineered vascular constructs. When these cues (TGF-beta1 and HA oligomers) were added to TNF-alpha-stimulated SMC cultures, model cell culture systems mimicking phenotypically-altered cells within aneurysms, they upregulated elastin matrix production, organized elastin protein into fibers, and simultaneously stabilized this matrix by attenuating production of elastolytic enzymes. Similarly these cues also attenuated inflammatory cytokines release within cells isolated from induced-aortic aneurysms in rats, and significantly upregulated elastin synthesis and matrix formation by upregulating LOX and desmosine protein amounts. The cues were also highly effective in organizing the elastin into fibrous matrix structures mimicking the native elastin deposition process. The outcomes of this study might be of tremendous use in optimizing design of HA constructs to modulate vascular healing and matrix synthesis following revascularization, and in enabling repair of elastin networks within diseased or inflammatory (aneurysmal) adult vascular tissues.

  6. Postural vascular response in human skin: passive and active reactions to alteration of transmural pressure.

    PubMed

    Jepsen, H; Gaehtgens, P

    1993-09-01

    Laser-Doppler (LD) fluxmetry was performed in the palmar finger skin of healthy subjects to study the mechanisms contributing to the postural vascular response. Local transmural pressure in the skin blood vessels of the region studied was altered for 1 min in two experimental series either by passive movement of the arm to different vertical hand positions relative to heart level or by application of external pressure (-120-180 mmHg) to the finger. Heart and respiratory rate, arterial blood pressure, and LD flux in the contralateral finger (kept at heart level) were measured. The measurements suggest a compound reaction of local (myogenic) and systemic (neurogenic) mechanisms: the local regulatory component appears as a graded active vascular response elicited by passive vessel distension or compression. A systemic component, associated with a single deep inspiration, is frequently observed during the actual movement of the arm. In addition, prolonged holding of the test hand in a given vertical position also elicits a delayed vascular response in the control hand at heart level, which may be generated by volume receptors in the intrathoracic low-pressure system.

  7. Platelet chemokines in vascular disease

    PubMed Central

    Gleissner, Christian A.; von Hundelshausen, Philipp; Ley, Klaus

    2009-01-01

    Platelets are a rich source of different chemokines and express chemokine receptors. CXCL4 is highly abundant in platelets and involved in promoting monocyte arrest from rolling and monocyte differentiation to macrophages. CXCL4 can also associate with CCL5 and amplify its effect on monocytes. The megakaryocyte CXCL7 gene product is proteolytically cleaved into the strong neutrophil chemoattractant, NAP-2, which has also been implicated in repair cell homing to vascular lesions. Platelet adhesion can induce release of CCL2 and CXCL8 from endothelial cells. Conversely, the chemokines CCL17, CCL22 and CXCL12 made by other cells amplify platelet activation. Platelet chemokines enhance recruitment of various hematopoietic cells to the vascular wall, fostering processes such as neointima formation, atherosclerosis, and thrombosis but also vessel repair and regeneration after vascular injury. PMID:18723831

  8. Vascular trauma and prostacyclin release.

    PubMed

    Jeremy, J Y; Mikhailidis, D P; Dandona, P

    1984-10-01

    The effect of trauma on prostacyclin (PGI2) secretion by rat aorta was examined. Whereas cutting and puncturing markedly increased PGI2 secretion, sonication and stretch had no effect. Cutting and puncturing were also effective in stimulating further endogenous secretion of PGI2 from 'exhausted' aortic segments in whom PGI2 production had dwindled to a negligible rate. These experiments show that trauma is an important stimulator of PGI2 secretion, the exhaustion of PGI2 secretion by vascular segments is not due to the depletion of substrate (arachidonic acid) and that an unusually traumatic venepuncture may invalidate the subsequent assays of PGI2 and its stable metabolite, 6-oxo-PGF1 alpha, in plasma. The close relationship of vascular trauma to PGI2 release also suggests a possible cytoprotective effect of this prostanoid on vascular endothelium.

  9. Systemic oxidoreductive balance and vascular function in individuals without clinical manifestation of atherosclerosis

    PubMed Central

    Majer, Marcin; Gackowski, Daniel; Różalski, Rafał; Siomek-Górecka, Agnieszka; Oliński, Ryszard; Budzyński, Jacek

    2017-01-01

    Introduction Endothelial dysfunction is recognized as the earliest disorder in the development of atherosclerosis, in the pathogenesis of which oxidative stress plays a crucial role. The aim of this study was to determine the relationships between non-invasive parameters of vascular dysfunction and oxidative stress. Material and methods Forty-eight individuals without clinical manifestation of atherosclerosis were studied. The plasma concentrations of the following were determined in all 48 subjects: retinol, ascorbic acid, α-tocopherol and uric acid, as well as the products of oxidative DNA damage repair: 8-oxo-7,8-dihydro-2’-deoxyguanosine (8-oxodG) in blood leukocytes and urine, and 8-oxo-7,8-dihydroguanine (8-oxoGua) in urine. The following parameters of vascular dysfunction were also examined: flow- (FMD) and nitroglycerin- (NMD) mediated dilatation of the brachial artery, pulse pressure (PP), distensibility coefficient (DC), pulsation (PI) and resistance (RI) index, carotid intima-media thickness (cIMT), and ankle-brachial index (ABI). Results Individuals with an FMD value of ≥ 8.8% had significantly higher blood concentrations of antioxidative vitamins and lower concentrations of 8-oxodG in their urine and blood leukocytes than their counterparts. Blood concentration of alpha-tocopherol or ascorbic acid positively correlated with FMD, PI, RI, DC and ABI and negatively with PP and cIMT. The reverse was the case for 8-oxodG in urine and leukocytes. In multiple regression analysis, markers of oxidative DNA damage positively determined the variance in PP and ABI. Conclusions In persons without clinical manifestation of atherosclerosis, oxidative stress was an independent factor associated with vascular wall dysfunction, and a better predictor than smoking and blood concentrations of glucose, lipids and creatinine. PMID:29242843

  10. Mechanosensitive β-catenin signaling regulates lymphatic vascular development

    PubMed Central

    Cha, Boksik; Srinivasan, R. Sathish

    2016-01-01

    The Wnt/β-catenin signaling is an evolutionarily conserved pathway that plays a pivotal role in embryonic development and adult homeostasis. However, we have limited information about the involvement of Wnt/β-catenin signaling in the lymphatic vascular system that regulates fluid homeostasis by absorbing interstitial fluid and returning it to blood circulation. In this recent publication we report that canonical Wnt/β-catenin signaling is highly active and critical for the formation of lymphovenus valves (LVVs) and lymphatic valves (LVs). β-catenin directly associates with the regulatory elements of the lymphedema-associated transcription factor, FOXC2 and activates its expression in an oscillatory shear stress (OSS)-dependent manner. The phenotype of β-catenin null embryos was rescued by FOXC2 overexpression. These results suggest that Wnt/β-catenin signaling is a mechanotransducer that links fluid force with lymphatic vascular development. [BMB Reports 2016; 49(8): 403-404] PMID:27418286

  11. VESsel GENeration Analysis (VESGEN): Innovative Vascular Mappings for Astronaut Exploration Health Risks and Human Terrestrial Medicine

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia; Kao, David; Valizadegan, Hamed; Martin, Rodney; Murray, Matthew C.; Ramesh, Sneha; Sekaran, Srinivaas

    2017-01-01

    Currently, astronauts face significant health risks in future long-duration exploration missions such as colonizing the Moon and traveling to Mars. Numerous risks include greatly increased radiation exposures beyond the low earth orbit (LEO) of the ISS, and visual and ocular impairments in response to microgravity environments. The cardiovascular system is a key mediator in human physiological responses to radiation and microgravity. Moreover, blood vessels are necessarily involved in the progression and treatment of vascular-dependent terrestrial diseases such as cancer, coronary vessel disease, wound-healing, reproductive disorders, and diabetes. NASA developed an innovative, globally requested beta-level software, VESsel GENeration Analysis (VESGEN) to map and quantify vascular remodeling for application to astronaut and terrestrial health challenges. VESGEN mappings of branching vascular trees and networks are based on a weighted multi-parametric analysis derived from vascular physiological branching rules. Complex vascular branching patterns are determined by biological signaling mechanisms together with the fluid mechanics of multi-phase laminar blood flow.

  12. Vascular Effects of Estrogenic Menopausal Hormone Therapy

    PubMed Central

    Reslan, Ossama M.; Khalil, Raouf A.

    2011-01-01

    Cardiovascular disease (CVD) is more common in men and postmenopausal women (Post-MW) than premenopausal women (Pre-MW). Despite recent advances in preventive measures, the incidence of CVD in women has shown a rise that matched the increase in the Post-MW population. The increased incidence of CVD in Post-MW has been related to the decline in estrogen levels, and hence suggested vascular benefits of endogenous estrogen. Experimental studies have identified estrogen receptor ERα, ERβ and a novel estrogen binding membrane protein GPR30 (GPER) in blood vessels of humans and experimental animals. The interaction of estrogen with vascular ERs mediates both genomic and non-genomic effects. Estrogen promotes endothelium-dependent relaxation by increasing nitric oxide, prostacyclin, and hyperpolarizing factor. Estrogen also inhibits the mechanisms of vascular smooth muscle (VSM) contraction including [Ca2+]i, protein kinase C and Rho-kinase. Additional effects of estrogen on the vascular cytoskeleton, extracellular matrix, lipid profile and the vascular inflammatory response have been reported. In addition to the experimental evidence in animal models and vascular cells, initial observational studies in women using menopausal hormonal therapy (MHT) have suggested that estrogen may protect against CVD. However, randomized clinical trials (RCTs) such as the Heart and Estrogen/progestin Replacement Study (HERS) and the Women’s Health Initiative (WHI), which examined the effects of conjugated equine estrogens (CEE) in older women with established CVD (HERS) or without overt CVD (WHI), failed to demonstrate protective vascular effects of estrogen treatment. Despite the initial set-back from the results of MHT RCTs, growing evidence now supports the ‘timing hypothesis’, which suggests that MHT could increase the risk of CVD if started late after menopause, but may produce beneficial cardiovascular effects in younger women during the perimenopausal period. The choice of

  13. Maternal exposure to cadmium during gestation perturbs the vascular system of the adult rat offspring

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ronco, Ana Maria, E-mail: amronco@inta.cl; Montenegro, Marcela; Castillo, Paula

    2011-03-01

    Several cardiovascular diseases (CVD) observed in adulthood have been associated with environmental influences during fetal growth. Here, we show that maternal exposure to cadmium, a ubiquitously distributed heavy metal and main component of cigarette smoke is able to induce cardiovascular morpho-functional changes in the offspring at adult age. Heart morphology and vascular reactivity were evaluated in the adult offspring of rats exposed to 30 ppm of cadmium during pregnancy. Echocardiographic examination shows altered heart morphology characterized by a concentric left ventricular hypertrophy. Also, we observed a reduced endothelium-dependent reactivity in isolated aortic rings of adult offspring, while endothelium-independent reactivity remainedmore » unaltered. These effects were associated with an increase of hem-oxygenase 1 (HO-1) expression in the aortas of adult offspring. The expression of HO-1 was higher in females than males, a finding likely related to the sex-dependent expression of the vascular cell adhesion molecule 1 (VCAM-1), which was lower in the adult female. All these long-term consequences were observed along with normal birth weights and absence of detectable levels of cadmium in fetal and adult tissues of the offspring. In placental tissues however, cadmium levels were detected and correlated with increased NF-{kappa}B expression - a transcription factor sensitive to inflammation and oxidative stress - suggesting a placentary mechanism that affect genes related to the development of the cardiovascular system. Our results provide, for the first time, direct experimental evidence supporting that exposure to cadmium during pregnancy reprograms cardiovascular development of the offspring which in turn may conduce to a long term increased risk of CVD.« less

  14. Bone vascularization: a way to study bone microarchitecture?

    NASA Astrophysics Data System (ADS)

    Blery, P.; Autrusseau, F.; Crauste, E.; Freuchet, Erwan; Weiss, Pierre; Guédon, J.-P.; Amouriq, Y.

    2014-03-01

    Trabecular bone and its microarchitecture are of prime importance for health. Studying vascularization helps to better know the relationship between bone and vascular microarchitecture. This research is an animal study (nine Lewis rats), based on the perfusion of vascularization by a contrast agent (a mixture of 50% barium sulfate with 1.5% of gelatin) before euthanasia. The samples were studied by micro CT at a resolution of 9μm. Softwares were used to show 3D volumes of bone and vessels, to calculate bone and vessels microarchitecture parameters. This study aims to understand simultaneously the bone microarchitecture and its vascular microarchitecture.

  15. Descriptive study of relationship between cardio-ankle vascular index and biomarkers in vascular-related diseases.

    PubMed

    Liu, Jinbo; Liu, Huan; Zhao, Hongwei; Shang, Guangyun; Zhou, Yingyan; Li, Lihong; Wang, Hongyu

    2017-01-01

    Cardio-ankle vascular index (CAVI) was supposed to be an independent predictor for vascular-related events. Biomarkers such as homocysteine (Hcy), N-terminal pro-brain natriuretic peptide (NT-proBNP), and urine albumin(microalbumin) (UAE) have involved the pathophysiological development of arteriosclerosis. The present study was to investigate relationship between CAVI and biomarkers in vascular-related diseases. A total of 656 subjects (M/F 272/384) from department of Vascular Medicine were enrolled into our study. They were divided into four groups according to the numbers of suffered diseases, healthy group (group 0: subjects without diseases of hypertension, diabetes mellitus (DM), coronary heart disease (CHD); n = 186), group 1 (with one of diseases of hypertension, CHD, DM; n = 237), group 2 (with two of diseases of hypertension, CHD, DM; n = 174), and group 3 (with all diseases of hypertension, CHD, DM; n = 59). CAVI was measured by VS-1000 apparatus. CAVI was increasing with increasing numbers of suffered vascular-related diseases. Similar results were found in the parameters of biomarkers such as Hcy, log NT-ProBNP, and log UAE. There were positive correlation between log NT-proBNP, Hcy, log UAE, and CAVI in the entire study group and nonhealthy group. Positive correlation between log UAE and CAVI were found in the entire study group after adjusting for age, body mass index (BMI), blood pressure, uric acid, and lipids. Multivariate analysis showed that log UAE was an independent associating factor of CAVI in all subjects. CAVI was significantly higher in subjects with hypertension, CHD, and DM. There was correlation between arterial stiffness and biomarkers such as NT-proBNP, Hcy, and UAE.

  16. [Localized purpura revealing vascular prosthetic graft infection].

    PubMed

    Boureau, A S; Lescalie, F; Cassagnau, E; Clairand, R; Connault, J

    2013-07-01

    Prosthetic graft infection after vascular reconstruction is a rare but serious complication. We report a case of infection occurring late after implantation of an iliofemoral prosthetic vascular graft. The Staphylococcus aureus infection was revealed by vascular purpura localized on the right leg 7 years after implantation of a vascular prosthesis. This case illustrates an uncommonly late clinical manifestation presenting as an acute infection 7 years after the primary operation. In this situation, the presentation differs from early infection, which generally occurs within the first four postoperative months. Diagnosis and treatment remain a difficult challenge because prosthetic graft infection is a potentially life-threatening complication. Morbidity and mortality rates are high. Here we detail specific aspects of the clinical and radiological presentation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  17. Concurrent generation of functional smooth muscle and endothelial cells via a vascular progenitor.

    PubMed

    Marchand, Melanie; Anderson, Erica K; Phadnis, Smruti M; Longaker, Michael T; Cooke, John P; Chen, Bertha; Reijo Pera, Renee A

    2014-01-01

    Smooth muscle cells (SMCs) and endothelial cells (ECs) are typically derived separately, with low efficiencies, from human pluripotent stem cells (hPSCs). The concurrent generation of these cell types might lead to potential applications in regenerative medicine to model, elucidate, and eventually treat vascular diseases. Here we report a robust two-step protocol that can be used to simultaneously generate large numbers of functional SMCs and ECs from a common proliferative vascular progenitor population via a two-dimensional culture system. We show here that coculturing hPSCs with OP9 cells in media supplemented with vascular endothelial growth factor, basic fibroblast growth factor, and bone morphogenetic protein 4 yields a higher percentage of CD31(+)CD34(+) cells on day 8 of differentiation. Upon exposure to endothelial differentiation media and SM differentiation media, these vascular progenitors were able to differentiate and mature into functional endothelial cells and smooth muscle cells, respectively. Furthermore, we were able to expand the intermediate population more than a billion fold to generate sufficient numbers of ECs and SMCs in parallel for potential therapeutic transplantations.

  18. Retinal vascular imaging in early life: insights into processes and risk of cardiovascular disease

    PubMed Central

    Li, Ling‐Jun; Ikram, Mohammad Kamran

    2015-01-01

    Abstract Cardiovascular disease (CVD) is the leading cause of morbidity and mortality globally. In recent years, studies have shown that the origins of CVD may be traced to vascular and metabolic processes in early life. Retinal vascular imaging is a new technology that allows detailed non‐invasive in vivo assessment and monitoring of the microvasculature. In this systematic review, we described the application of retinal vascular imaging in children and adolescents, and we examined the use of retinal vascular imaging in understanding CVD risk in early life. We reviewed all publications with quantitative retinal vascular assessment in two databases: PubMed and Scopus. Early life CVD risk factors were classified into four groups: birth risk factors, environmental risk factors, systemic risk factors and conditions linked to future CVD development. Retinal vascular changes were associated with lower birth weight, shorter gestational age, low‐fibre and high‐sugar diet, lesser physical activity, parental hypertension history, childhood hypertension, childhood overweight/obesity, childhood depression/anxiety and childhood type 1 diabetes mellitus. In summary, there is increasing evidence supporting the view that structural changes in the retinal microvasculature are associated with CVD risk factors in early life. Thus, the retina is a useful site for pre‐clinical assessment of microvascular processes that may underlie the future development of CVD in adulthood. PMID:26435039

  19. [Oxidative stress and vascular function].

    PubMed

    Urbański, Karol; Nowak, Michal; Guzik, Tomasz J

    2013-01-01

    The maintenance of blood vessel homeostasis is closely associated with Reactive Oxygen and Nitrogen Species (ROS and RNS) production in the blood vessel wall. The main molecules taking part in this process are nitric oxide (NO), superoxide anion (O2*-), hydrogen peroxide (H2O2) and their derivatives. The production of these factors occurs in health and disease, however the increased ROS release is often referred to as oxidative stress. While initially oxidative stress was considered systemically, recent data indicate that it occurs locally in subcellular spaces and may be a result of dysfunction of individual enzyme systems. Oxidative stress induces inflammation, proliferation and migration of vascular smooth muscle cells, may regulate apoptosis and the function of the cells of vascular wall, finally leading to dysfunction of endothelium, media and adventitia, leading to cardiovascular diseases such as atherosclerosis, hypertension or heart failure. It is believed that a family of NADPH oxidases is the main source of ROS in the vessel wall, but also in other organs and tissues. It consists of seven known and quite precisely characterized homologues (NOX1, NOX2, NOX3, NOX4, NOX5, DUOX1 and DUOX2) which often have very distinct activity and cellular localization and function. Besides harmful actions, we are beginning to understand the protective effects of ROS and RNS. They have many functions regulating redox-sensitive gene expression and influencing a proper function of cells and vessels. NOX4 has been particularly well characterized in this respect. Thus, the maintenance of the right homeostasis depends not only on ROS removing capabilities, but especially on preserving the adequate level of ROS production.

  20. Structural and functional imaging for vascular targeted photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Li, Buhong; Gu, Ying; Wilson, Brian C.

    2017-02-01

    Vascular targeted photodynamic therapy (V-PDT) has been widely used for the prevention or treatment of vascular-related diseases, such as localized prostate cancer, wet age-related macular degeneration, port wine stains, esophageal varices and bleeding gastrointestinal mucosal lesions. In this study, the fundamental mechanisms of vascular responses during and after V-PDT will be introduced. Based on the V-PDT treatment of blood vessels in dorsal skinfold window chamber model, the structural and functional imaging, which including white light microscopy, laser speckle imaging, singlet oxygen luminescence imaging, and fluorescence imaging for evaluating vascular damage will be presented, respectively. The results indicate that vessel constriction and blood flow dynamics could be considered as the crucial biomarkers for quantitative evaluation of vascular damage. In addition, future perspectives of non-invasive optical imaging for evaluating vascular damage of V-PDT will be discussed.

  1. Bilaterally symmetric axes with rhizoids composed the rooting structure of the common ancestor of vascular plants.

    PubMed

    Hetherington, Alexander J; Dolan, Liam

    2018-02-05

    There are two general types of rooting systems in extant land plants: gametophyte rhizoids and sporophyte root axes. These structures carry out the rooting function in the free-living stage of almost all land plant gametophytes and sporophytes, respectively. Extant vascular plants develop a dominant, free-living sporophyte on which roots form, with the exception of a small number of taxa that have secondarily lost roots. However, fossil evidence indicates that early vascular plants did not develop sporophyte roots. We propose that the common ancestor of vascular plants developed a unique rooting system-rhizoidal sporophyte axes. Here we present a synthesis and reinterpretation of the rootless sporophytes of Horneophyton lignieri , Aglaophyton majus , Rhynia gwynne-vaughanii and Nothia aphylla preserved in the Rhynie chert. We show that the sporophyte rooting structures of all four plants comprised regions of plagiotropic (horizontal) axes that developed unicellular rhizoids on their underside. These regions of axes with rhizoids developed bilateral symmetry making them distinct from the other regions which were radially symmetrical. We hypothesize that rhizoidal sporophyte axes constituted the rooting structures in the common ancestor of vascular plants because the phylogenetic positions of these plants span the origin of the vascular lineage.This article is part of a discussion meeting issue 'The Rhynie cherts: our earliest terrestrial ecosystem revisited'. © 2017 The Authors.

  2. Commentary on: "Vascular distensibilities have minor effects on intracardiac shunt patterns in reptiles" by Filogonio et al. (2017).

    PubMed

    Hillman, Stanley S; Hedrick, Michael S; Kohl, Zachary F

    2017-06-01

    The recent study by Filogonio et al. (2017) suggested that net cardiac shunt patterns in two species of reptiles (Trachemys scripta and Crotalus durissus) were not significantly influenced by the vascular distensibilities of the systemic and pulmonary vasculatures. This is in contrast to a previously published study (Hillman et al., 2014) in the toad (Rhinella marina) in which net cardiac shunts were predicted primarily by the physical properties of vascular distensibility rather than physiological control of resistance of the systemic and pulmonary vasculature. We analyze the data and conclusions reached by Filogonio et al. (2017) regarding the role of vascular distensibilities in determining net cardiac shunt patterns in reptiles in comparison with toads. In our view, the conclusions reached by Filogonio et al. (2017) are not supported by the data primarily because vascular distensibilities were not measured in the reptiles analyzed in their study. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. Management of Major Vascular Injury: Open.

    PubMed

    Tisherman, Samuel A

    2016-06-01

    Major blood vessels are in proximity to other vital structures in the neck and base of skull. Infections and tumors of the head and neck can invade vascular structures. Vascular injuries can lead to massive hemorrhage, cerebral ischemia, or stroke. Emergency and definitive management can be challenging. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Three-dimensional photoacoustic imaging of vascular anatomy in small animals using an optical detection system

    NASA Astrophysics Data System (ADS)

    Zhang, Edward Z.; Laufer, Jan; Beard, Paul

    2007-02-01

    A 3D photoacoustic imaging instrument for characterising small animal models of human disease processes has been developed. The system comprises an OPO excitation source and a backward-mode planar ultrasound imaging head based upon a Fabry Perot polymer film sensing interferometer (FPI). The mirrors of the latter are transparent between 590 - 1200nm but highly reflective between 1500-1600nm. This enables nanosecond excitation laser pulses in the former wavelength range, where biological tissues are relatively transparent, to be transmitted through the sensor head into the tissue. The resulting photoacoustic signals arrive at the sensor where they modulate the optical thickness of the FPI and therefore its reflectivity. By scanning a CW focused interrogating laser beam at 1550nm across the surface of the sensor, the spatial-temporal distribution of the photoacoustic signals can therefore be mapped in 2D enabling a 3D photoacoustic image to be reconstructed. To demonstrate the application of the system to imaging small animals such as mice, 3D images of the vascular anatomy of the mouse brain and the microvasculature in the skin around the abdomen were obtained non invasively. It is considered that this system provides a practical alternative to photoacoustic scanners based upon piezoelectric detectors for high resolution non invasive small animal imaging.

  5. Mixed vascular nevus syndrome: a report of four new cases and a literature review

    PubMed Central

    Polizzi, Agata; Strano, Serena; Schepis, Carmelo; Morano, Massimiliano; Belfiore, Giuseppe; Palmucci, Stefano; Foti, Pietro Valerio; Pirrone, Concetta; Sofia, Vito; David, Emanuele; Salpietro, Vincenzo; Mankad, Kshitij; Milone, Pietro

    2016-01-01

    Background Mixed vascular nevus (or nevus vascularis mixtus) represents an admixture of cutaneous vascular malformations of the telangiectatic type and angiospastic spots of nevus anemicus. It can occur as an purely cutaneous trait or as a hallmark of a neurocutaneous phenotype (mixed vascular nevus syndrome) characterised by the combination of: (I) paired vascular (telangiectatic and anemic) twin nevi and brain abnormalities of the Dyke-Davidoff-Masson type (i.e., crossed cerebral/cerebellar hemiatrophy with hypoplasia of the ipsilateral cerebral vessels and homolateral hypertrophy of the skull and sinuses (hyperpneumatisation) with contralateral hemispheric hypertrophy); or (II) paired vascular twin nevi and brain malformations of the Dyke-Davidoff-Masson type in association with systemic abnormalities consisting in facial asymmetry, skeletal anomalies (i.e., Legg-Calvé-Perthes-like disease) and disorders of autoimmunity (i.e., diabetes, thyroiditis). In 2014, Happle proposed to name the syndrome with the eponym Ruggieri-Leech syndrome. Methods Review of the existing literature on nevus vascularis mixtus and information on our personal experience on new cases and follow-up of previously reported cases by some of us. Results The existing literature revealed 4 previous studies including 33 cases with an inferred purely cutaneous trait and 3 cases with a combination of paired vascular twin nevi and brain malformation of the Dyke-Davidoff-Masson type. Our personal experience includes 4 unpublished patients (1 female and 3 males; currently aged 2 to 34 years) seen and followed-up at our Institutions in Italy who had: paired vascular nevi involving either the face (n=2) or the face and parts of the body (n=2); facial asymmetry (n=4); mild to moderate facial dysmorphic features (n=2); developmental delay (n=3); seizures/stroke-like episodes and associated hemiplegia (n=4); muscular hypotrophy (n=2); mild to moderate hemispheric atrophy (n=4); skull osseous hypertrophy

  6. A national survey of evolving management patterns for vascular injury.

    PubMed

    Burkhardt, Gabriel E; Rasmussen, Todd E; Propper, Brandon W; Lopez, Peter L; Gifford, Shaun M; Clouse, W Darrin

    2009-01-01

    The modern era has witnessed an increase in endovascular techniques used by physicians to treat vascular injury and age-related disease. As a consequence, the number of open vascular operations available for general surgical education has decreased dramatically. This changing paradigm threatens competence in vascular injury management achieved during surgical residency. The objective of this study is to sample perceptions on vascular injury treatment in the United States to highlight the need for planning for this important tenet of surgical education. An electronic survey was extended to board-certified surgeons through 3 professional societies, the Peripheral Vascular Surgery Society (PVSS), the Eastern Association for the Surgery of Trauma (EAST), and the American College of Surgeons (ACS). A total of 520 respondents were self-categorized as trauma (59%; n = 307), vascular (17%; n = 90), or general (19%; n = 99) surgeons. Respondents reported that general surgeons currently manage less than 10% of vascular injuries at their respective institutions. A 2.5-fold increase in endovascular treatment of vascular injury during the past decade was reported with interventional radiologists now involved in the management of up to 25% of injuries. Few general or trauma surgeons surveyed possessed a catheter-based skill set, although 38% of trauma surgeons expressed great interest in endovascular training. Additionally, a cadre of vascular surgeons (67%) affirmed a commitment to teaching vascular injury management. The results of this study confirm a diminished role for non-fellowship-trained surgeons in managing vascular injury. Despite an increased acceptance of endovascular techniques to manage trauma, general and trauma surgeons do not possess the skill set. Collaboration between surgical communities will be especially important to maintain high standards in vascular injury management.

  7. A Novel Human Tissue-Engineered 3-D Functional Vascularized Cardiac Muscle Construct

    PubMed Central

    Valarmathi, Mani T.; Fuseler, John W.; Davis, Jeffrey M.; Price, Robert L.

    2017-01-01

    Organ tissue engineering, including cardiovascular tissues, has been an area of intense investigation. The major challenge to these approaches has been the inability to vascularize and perfuse the in vitro engineered tissue constructs. Attempts to provide oxygen and nutrients to the cells contained in the biomaterial constructs have had varying degrees of success. The aim of this current study is to develop a three-dimensional (3-D) model of vascularized cardiac tissue to examine the concurrent temporal and spatial regulation of cardiomyogenesis in the context of postnatal de novo vasculogenesis during stem cell cardiac regeneration. In order to achieve the above aim, we have developed an in vitro 3-D functional vascularized cardiac muscle construct using human induced pluripotent stem cell-derived embryonic cardiac myocytes (hiPSC-ECMs) and human mesenchymal stem cells (hMSCs). First, to generate the prevascularized scaffold, human cardiac microvascular endothelial cells (hCMVECs) and hMSCs were co-cultured onto a 3-D collagen cell carrier (CCC) for 7 days under vasculogenic culture conditions. In this milieu, hCMVECs/hMSCs underwent maturation, differentiation, and morphogenesis characteristic of microvessels, and formed extensive plexuses of vascular networks. Next, the hiPSC-ECMs and hMSCs were co-cultured onto this generated prevascularized CCCs for further 7 or 14 days in myogenic culture conditions. Finally, the vascular and cardiac phenotypic inductions were analyzed at the morphological, immunological, biochemical, molecular, and functional levels. Expression and functional analyses of the differentiated cells revealed neo-angiogenesis and neo-cardiomyogenesis. Thus, our unique 3-D co-culture system provided us the apt in vitro functional vascularized 3-D cardiac patch that can be utilized for cellular cardiomyoplasty. PMID:28194397

  8. The Effects of Endurance Exercise Training on the Coronary Vascular Responsiveness to Intracoronary Acetylcholine in Swine

    DTIC Science & Technology

    1993-04-09

    systems. The mechanisms of sympathet ic innervation involve a-adrenergic-mediated coronary vascular smooth muscle contraction, and (1- adrenergic-mediated...may cause muscarinic-mediated relaxation or contraction of vascular smooth muscle , depending on the animal species and presence of endothelial...both cardiac muscle layers receive equal flows over a cardiac cycle, regardless of the differences from systo lic compression (Buckberg and Kattus

  9. Arterial ageing: from endothelial dysfunction to vascular calcification.

    PubMed

    Tesauro, M; Mauriello, A; Rovella, V; Annicchiarico-Petruzzelli, M; Cardillo, C; Melino, G; Di Daniele, N

    2017-05-01

    Complex structural and functional changes occur in the arterial system with advancing age. The aged artery is characterized by changes in microRNA expression patterns, autophagy, smooth muscle cell migration and proliferation, and arterial calcification with progressively increased mechanical vessel rigidity and stiffness. With age the vascular smooth muscle cells modify their phenotype from contractile to 'synthetic' determining the development of intimal thickening as early as the second decade of life as an adaptive response to forces acting on the arterial wall. The increased permeability observed in intimal thickening could represent the substrate on which low-level atherosclerotic stimuli can promote the development of advanced atherosclerotic lesions. In elderly patients the atherosclerotic plaques tend to be larger with increased vascular stenosis. In these plaques there is a progressive accumulation of both lipids and collagen and a decrease of inflammation. Similarly the plaques from elderly patients show more calcification as compared with those from younger patients. The coronary artery calcium score is a well-established marker of adverse cardiovascular outcomes. The presence of diffuse calcification in a severely stenotic segment probably induces changes in mechanical properties and shear stress of the arterial wall favouring the rupture of a vulnerable lesion in a less stenotic adjacent segment. Oxidative stress and inflammation appear to be the two primary pathological mechanisms of ageing-related endothelial dysfunction even in the absence of clinical disease. Arterial ageing is no longer considered an inexorable process. Only a better understanding of the link between ageing and vascular dysfunction can lead to significant advances in both preventative and therapeutic treatments with the aim that in the future vascular ageing may be halted or even reversed. © 2017 The Association for the Publication of the Journal of Internal Medicine.

  10. Chronic psychological stress induces vascular inflammation in rabbits.

    PubMed

    Lu, Xiao Ting; Liu, Yun Fang; Zhao, Li; Li, Wen Jing; Yang, Rui Xue; Yan, Fang Fang; Zhao, Yu Xia; Jiang, Fan

    2013-01-01

    Psychological stress is associated with a systemic inflammatory response. It is unclear, however, whether psychological stress contributes to vascular inflammation. Here, we examined the effects of unpredictable chronic mild stress (UCMS) on vascular inflammation in rabbits. One hundred rabbits were randomly divided into control and stress groups. UCMS was induced by a set of defined adverse conditions applied in a shuffled order for 4, 8, 12, or 16 weeks, and rabbits were killed 24 h after the end of the UCMS protocol. Expression of different inflammatory molecules was analyzed by real-time polymerase chain reaction, immunohistochemistry, or enzyme-linked immunosorbent assay. UCMS resulted in depression-like behaviors, decreased body weight gain, and hypertension with no significant effects on serum lipids. Aortic mRNA and protein expression for tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), monocyte chemoattractant protein-1 (MCP-1), macrophage migration inhibitory factor, and expression of intercellular adhesion molecule-1 (ICAM-1) protein were increased. UCMS increased circulating concentrations of corticosterone, TNF-α, and CRP throughout. Moreover, stress downregulated the expression of endothelial nitric oxide synthase. At 16 weeks of UCMS, macrophage infiltration and lipid accumulation in the subendothelial space were detected in the aorta. In cultured murine vascular smooth muscle cells, treatment with serum from stressed rabbits significantly increased phosphorylation of p38 and c-Jun N-terminal kinase (JNK), and upregulated expression of MCP-1 and ICAM-1 mRNAs, in which the effect was blunted by a TNF-α neutralizing antibody or p38 and JNK inhibitors. Our results indicate that chronic psychological stress induces vascular inflammation via TNF-α and p38/JNK pathways, which may contribute to the development of atherosclerosis.

  11. Vascular plugs - A key companion to Interventionists - 'Just Plug it'.

    PubMed

    Ramakrishnan, Sivasubramanian

    2015-01-01

    Vascular plugs are ideally suited to close extra-cardiac, high flowing vascular communications. The family of vascular plugs has expanded. Vascular plugs in general have a lower profile and the newer variants can be delivered even through a diagnostic catheter. These features make them versatile and easy to use. The Amplatzer vascular plugs are also used for closing intracardiac defects including coronary arterio-venous fistula and paravalvular leakage in an off-label fashion. In this review, the features of currently available vascular plugs are reviewed along with tips and tricks of using them in the cardiac catheterization laboratory. Copyright © 2015. Published by Elsevier B.V.

  12. Design and development of multilayer vascular graft

    NASA Astrophysics Data System (ADS)

    Madhavan, Krishna

    2011-07-01

    Vascular graft is a widely-used medical device for the treatment of vascular diseases such as atherosclerosis and aneurysm as well as for the use of vascular access and pediatric shunt, which are major causes of mortality and morbidity in this world. Dysfunction of vascular grafts often occurs, particularly for grafts with diameter less than 6mm, and is associated with the design of graft materials. Mechanical strength, compliance, permeability, endothelialization and availability are issues of most concern for vascular graft materials. To address these issues, we have designed a biodegradable, compliant graft made of hybrid multilayer by combining an intimal equivalent, electrospun heparin-impregnated poly-epsilon-caprolactone nanofibers, with a medial equivalent, a crosslinked collagen-chitosan-based gel scaffold. The intimal equivalent is designed to build mechanical strength and stability suitable for in vivo grafting and to prevent thrombosis. The medial equivalent is designed to serve as a scaffold for the activity of the smooth muscle cells important for vascular healing and regeneration. Our results have shown that genipin is a biocompatible crosslinker to enhance the mechanical properties of collagen-chitosan based scaffolds, and the degradation time and the activity of smooth muscle cells in the scaffold can be modulated by the crosslinking degree. For vascular grafting and regeneration in vivo, an important design parameter of the hybrid multilayer is the interface adhesion between the intimal and medial equivalents. With diametrically opposite affinities to water, delamination of the two layers occurs. Physical or chemical modification techniques were thus used to enhance the adhesion. Microscopic examination and graft-relevant functional characterizations have been performed to evaluate these techniques. Results from characterization of microstructure and functional properties, including burst strength, compliance, water permeability and suture

  13. Graph analysis of cell clusters forming vascular networks

    NASA Astrophysics Data System (ADS)

    Alves, A. P.; Mesquita, O. N.; Gómez-Gardeñes, J.; Agero, U.

    2018-03-01

    This manuscript describes the experimental observation of vasculogenesis in chick embryos by means of network analysis. The formation of the vascular network was observed in the area opaca of embryos from 40 to 55 h of development. In the area opaca endothelial cell clusters self-organize as a primitive and approximately regular network of capillaries. The process was observed by bright-field microscopy in control embryos and in embryos treated with Bevacizumab (Avastin), an antibody that inhibits the signalling of the vascular endothelial growth factor (VEGF). The sequence of images of the vascular growth were thresholded, and used to quantify the forming network in control and Avastin-treated embryos. This characterization is made by measuring vessels density, number of cell clusters and the largest cluster density. From the original images, the topology of the vascular network was extracted and characterized by means of the usual network metrics such as: the degree distribution, average clustering coefficient, average short path length and assortativity, among others. This analysis allows to monitor how the largest connected cluster of the vascular network evolves in time and provides with quantitative evidence of the disruptive effects that Avastin has on the tree structure of vascular networks.

  14. Aluminum exposure for one hour decreases vascular reactivity in conductance and resistance arteries in rats

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schmidt, Patrícia Medeiros; Escobar, Alyne Goulart

    vascular system. - Highlights: • One hour of aluminum exposure decreases vascular reactivity. • Vascular imbalance after aluminum exposure is related to increased oxidative stress. • Enhanced NO release is the first step against the effects of Al at vascular system.« less

  15. Current and future initiatives for vascular health management in clinical practice

    PubMed Central

    Cameron, James D; Asmar, Roland; Struijker-Boudier, Harry; Shirai, Kohji; Sirenko, Yuriy; Kotovskaya, Yulia; Topouchian, Jirar

    2013-01-01

    Central arterial structure and function comprise a primary determinant of vascular health, and are integral to the important concept of ventriculo-vascular coupling or interaction. Central aortic stiffening is a major influence on central blood pressure, and directly relates to coronary perfusion. The joint session of the International Society of Vascular Health (Eastern Region) and the Ukrainian Congress of Cardiology was held in Kiev, Ukraine, on September 23, 2011; it provided an expert forum to discuss arterial evaluations, clinical applications, and progress toward translating arterial protection into cardiovascular benefits. The conclusions of the expert panel were: Aortic stiffness is not presently a treatment target but may be useful for substratifying cardiovascular risk in individuals in order to better target the intensity of conventional therapy, and it may be useful in assessing response to treatment.Crosstalk between macro- and microcirculation in hypertension has important implications for pharmacological treatment. An antihypertensive regimen should abolish the vicious cycle between the increased resistance in the microcirculation and the increased stiffness of the larger arteries. Such treatment should be based on drugs with multiple actions on the vascular tree, or on drug combinations that target the various segments of the arterial system.Several blood pressure-independent mechanisms of large artery stiffness exist. Future considerations for clinical understanding of large artery stiffness should involve new drugs and new evaluation methods – with a focus on vascular health, for the initiation of cardiovascular prevention, for newly designed studies for treatment evaluation, and for new studies of drug combinations.Arterial stiffening is a sign of cardiovascular aging and is a major factor affecting the biomechanics of large arteries. Arterial stiffness is an attractive therapeutic target in terms of vascular aging. Healthy lifestyle, physical

  16. Vascular surgical data registries for small computers.

    PubMed

    Kaufman, J L; Rosenberg, N

    1984-08-01

    Recent designs for computer-based vascular surgical registries and clinical data bases have employed large centralized systems with formal programming and mass storage. Small computers, of the types created for office use or for word processing, now contain sufficient speed and memory storage capacity to allow construction of decentralized office-based registries. Using a standardized dictionary of terms and a method of data organization adapted to word processing, we have created a new vascular surgery data registry, "VASREG." Data files are organized without programming, and a limited number of powerful logical statements in English are used for sorting. The capacity is 25,000 records with current inexpensive memory technology. VASREG is adaptable to computers made by a variety of manufacturers, and interface programs are available for conversion of the word processor formated registry data into forms suitable for analysis by programs written in a standard programming language. This is a low-cost clinical data registry available to any physician. With a standardized dictionary, preparation of regional and national statistical summaries may be facilitated.

  17. Hydrogels for Engineering of Perfusable Vascular Networks

    PubMed Central

    Liu, Juan; Zheng, Huaiyuan; Poh, Patrina S. P.; Machens, Hans-Günther; Schilling, Arndt F.

    2015-01-01

    Hydrogels are commonly used biomaterials for tissue engineering. With their high-water content, good biocompatibility and biodegradability they resemble the natural extracellular environment and have been widely used as scaffolds for 3D cell culture and studies of cell biology. The possible size of such hydrogel constructs with embedded cells is limited by the cellular demand for oxygen and nutrients. For the fabrication of large and complex tissue constructs, vascular structures become necessary within the hydrogels to supply the encapsulated cells. In this review, we discuss the types of hydrogels that are currently used for the fabrication of constructs with embedded vascular networks, the key properties of hydrogels needed for this purpose and current techniques to engineer perfusable vascular structures into these hydrogels. We then discuss directions for future research aimed at engineering of vascularized tissue for implantation. PMID:26184185

  18. Comparative characterization of stromal vascular cells derived from three types of vascular wall and adipose tissue.

    PubMed

    Yang, Santsun; Eto, Hitomi; Kato, Harunosuke; Doi, Kentaro; Kuno, Shinichiro; Kinoshita, Kahori; Ma, Hsu; Tsai, Chi-Han; Chou, Wan-Ting; Yoshimura, Kotaro

    2013-12-01

    Multipotent stem/progenitor cells localize perivascularly in many organs and vessel walls. These tissue-resident stem/progenitor cells differentiate into vascular endothelial cells, pericytes, and other mesenchymal lineages, and participate in physiological maintenance and repair of vasculatures. In this study, we characterized stromal vascular cells obtained through the explant culture method from three different vessel walls in humans: arterial wall (ART; >500 μm in diameter), venous wall (VN; >500 μm in diameter), and small vessels in adipose tissue (SV; arterioles and venules, <100 μm in diameter). These were examined for functionality and compared with adipose-derived stem/stromal cells (ASCs). All stromal vascular cells of different origins presented fibroblast-like morphology and we could not visually discriminate one population from another. Flow cytometry showed that the cultured population heterogeneously expressed a variety of surface antigens associated with stem/progenitor cells, but CD105 was expressed by most cells in all groups, suggesting that the cells generally shared the characteristics of mesenchymal stem cells. Our histological and flow cytometric data suggested that the main population of vessel wall-derived stromal vascular cells were CD34(+)/CD31(-) and came from the tunica adventitia and areola tissue surrounding the adventitia. CD271 (p75NTR) was expressed by the vasa vasorum in the VN adventitia and by a limited population in the adventitia of SV. All three populations differentiated into multiple lineages as did ASCs. ART cells induced the largest quantity of calcium formation in the osteogenic medium, whereas ASCs showed the greatest adipogenic differentiation. SV and VN stromal cells had greater potency for network formation than did ART stromal cells. In conclusion, the three stromal vascular populations exhibited differential functional properties. Our results have clinical implications for vascular diseases such as

  19. Identification of Biomarkers for Patients With Vascular Anomalies

    ClinicalTrials.gov

    2018-02-12

    Vascular Anomaly; Generalized Lymphatic Anomaly; Kaposiform Hemangioendothelioma; Kaposiform Lymphangiomatosis; Gorham-Stout Disease; Klippel Trenaunay Syndrome; Congenital Lipomatous Overgrowth, Vascular Malformations, and Epidermal Nevi

  20. THE VASCULAR PATHOPHYSIOLOGY OF AN IRRADIATED GRAFT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rubin, P.; Casarett, G.; Grise, J.W.

    1960-06-01

    The difference in the vascularization of grafted and normal skin forms a reasonable basis for explaining the differences in the radiation reactions of these structures. The radioisotope half time of disappearance following subcutaneous injection is an index of vascular integrity of the graft and serves as a parameter to predict its radioresponsiveness. In developing a concept of the spectrum of reactions of grafted skin to ionizing irradiation, knowledge of the radiopathologic changes in capillaries must be utilized with knowledge of the histophysiology of the vascularity of an autograft. (auth)

  1. Vascular ring complicates accidental button battery ingestion.

    PubMed

    Mercer, Ronald W; Schwartz, Matthew C; Stephany, Joshua; Donnelly, Lane F; Franciosi, James P; Epelman, Monica

    2015-01-01

    Button battery ingestion can lead to dangerous complications, including vasculoesophageal fistula formation. The presence of a vascular ring may complicate battery ingestion if the battery lodges at the level of the ring and its important vascular structures. We report a 4-year-old boy with trisomy 21 who was diagnosed with a vascular ring at the time of button battery ingestion and died 9 days after presentation due to massive upper gastrointestinal bleeding from esophageal erosion and vasculoesophageal fistula formation. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Transcatheter aortic valve replacement and vascular complications definitions.

    PubMed

    Van Mieghem, Nicolas M; Généreux, Philippe; van der Boon, Robert M A; Kodali, Susheel; Head, Stuart; Williams, Matthew; Daneault, Benoit; Kappetein, Arie-Pieter; de Jaegere, Peter P; Leon, Martin B; Serruys, Patrick W

    2014-03-20

    Transcatheter aortic valve replacement (TAVR) requires large calibre catheters and is therefore associated with increased vascular complications. The aim of this study was to illustrate the impact of the different definitions of major vascular complications on their incidence and to underscore the importance of uniform reporting. We pooled dedicated databases of consecutive patients undergoing TAVR from two tertiary care facilities and looked for the incidence of major vascular complications using various previously reported definitions. The level of agreement (Kappa statistic) between the respective definitions and the Valve Academic Research Consortium (VARC) consensus definition of vascular complications was assessed. A total of 345 consecutive patients underwent transfemoral TAVR and were included in this analysis. A completely percutaneous access and closure technique was applied in 96% of cases. Arterial sheath size ranged between 18 and 24 Fr, the majority being 18 Fr (60%). Procedural success was reached in 94.5%. Depending on the definition used, major vascular complications occurred in 5.2-15.9% of patients. According to the VARC definitions, the rate of major and minor vascular complications was 9.0% and 9.6%, respectively. Major vascular complications according to VARC criteria demonstrated at least a substantial level of agreement with the SOURCE registry (k 0.80), the UK registry (k 0.82) the Italian registry (k 0.72) and "FRANCE" registry (k 0.70) definitions, compared to a moderate level of agreement with the definitions used in the German registry ( 0.47) and the 18 Fr Safety and Efficacy study (k 0.42). Minor complications according to VARC demonstrated a moderate agreement only with vascular complications using the German registry definition (k 0.54). Non-uniformity in how vascular complications are defined precludes any reliable comparison between previously reported TAVR registries. The VARC consensus document offers standardised endpoint

  3. Physics of vascular brachytherapy.

    PubMed

    Jani, S K

    1999-08-01

    Basic physics plays an important role in understanding the clinical utility of radioisotopes in brachytherapy. Vascular brachytherapy is a very unique application of localized radiation in that dose levels very close to the source are employed to treat tissues within the arterial wall. This article covers basic physics of radioactivity and differentiates between beta and gamma radiations. Physical parameters such as activity, half-life, exposure and absorbed dose have been explained. Finally, the dose distribution around a point source and a linear source is described. The principles of basic physics are likely to play an important role in shaping the emerging technology and its application in vascular brachytherapy.

  4. Co-delivery of vascular endothelial growth factor and angiopoietin-1 using injectable microsphere/hydrogel hybrid systems for therapeutic angiogenesis.

    PubMed

    Shin, Seung-Hwa; Lee, Jangwook; Ahn, Dong-Gyun; Lee, Kuen Yong

    2013-08-01

    We hypothesized that combined delivery of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) using microsphere/hydrogel hybrid systems could enhance mature vessel formation compared with administration of each factor alone. Hybrid delivery systems composed of alginate hydrogels and poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres containing angiogenic factors were prepared. The release behavior of angiogenic factors from hybrid systems was monitored in vitro. The hybrid systems were injected into an ischemic rodent model, and blood vessel formation at the ischemic site was evaluated. The sustained release over 4 weeks of both VEGF and Ang-1 from hybrid systems was achieved in vitro. Co-delivery of VEGF and Ang-1 was advantageous to retain muscle tissues and significantly induced vessel enlargement at the ischemic site, compared to mice treated with either VEGF or Ang-1 alone. Sustained and combined delivery of VEGF and Ang-1 significantly enhances vessel enlargement at the ischemic site, compared with sustained delivery of either factor alone. Microsphere/hydrogel hybrid systems may be a promising vehicle for delivery of multiple drugs for many therapeutic applications.

  5. Simulation of minimally invasive vascular interventions for training purposes.

    PubMed

    Alderliesten, Tanja; Konings, Maurits K; Niessen, Wiro J

    2004-01-01

    To master the skills required to perform minimally invasive vascular interventions, proper training is essential. A computer simulation environment has been developed to provide such training. The simulation is based on an algorithm specifically developed to simulate the motion of a guide wire--the main instrument used during these interventions--in the human vasculature. In this paper, the design and model of the computer simulation environment is described and first results obtained with phantom and patient data are presented. To simulate minimally invasive vascular interventions, a discrete representation of a guide wire is used which allows modeling of guide wires with different physical properties. An algorithm for simulating the propagation of a guide wire within a vascular system, on the basis of the principle of minimization of energy, has been developed. Both longitudinal translation and rotation are incorporated as possibilities for manipulating the guide wire. The simulation is based on quasi-static mechanics. Two types of energy are introduced: internal energy related to the bending of the guide wire, and external energy resulting from the elastic deformation of the vessel wall. A series of experiments were performed on phantom and patient data. Simulation results are qualitatively compared with 3D rotational angiography data. The results indicate plausible behavior of the simulation.

  6. Vinpocetine Attenuates the Osteoblastic Differentiation of Vascular Smooth Muscle Cells

    PubMed Central

    Chen, Xiu-Juan; Wang, Na; Yi, Peng-Fei; Song, Min; Zhang, Bo; Wang, Yu-Zhong; Liang, Qiu-Hua

    2016-01-01

    Vascular calcification is an active process of osteoblastic differentiation of vascular smooth muscle cells; however, its definite mechanism remains unknown. Vinpocetine, a derivative of the alkaloid vincamine, has been demonstrated to inhibit the high glucose-induced proliferation of vascular smooth muscle cells; however, it remains unknown whether vinpocetine can affect the osteoblastic differentiation of vascular smooth muscle cells. We hereby investigated the effect of vinpocetine on vascular calcification using a beta-glycerophosphate-induced cell model. Our results showed that vinpocetine significantly reduced the osteoblast-like phenotypes of vascular smooth muscle cells including ALP activity, osteocalcin, collagen type I, Runx2 and BMP-2 expression as well as the formation of mineralized nodule. Vinpocetine, binding to translocation protein, induced phosphorylation of extracellular signal-related kinase and Akt and thus inhibited the translocation of nuclear factor-kappa B into the nucleus. Silencing of translocator protein significantly attenuated the inhibitory effect of vinpocetine on osteoblastic differentiation of vascular smooth muscle cells. Taken together, vinpocetine may be a promising candidate for the clinical therapy of vascular calcification. PMID:27589055

  7. Vinpocetine Attenuates the Osteoblastic Differentiation of Vascular Smooth Muscle Cells.

    PubMed

    Ma, Yun-Yun; Sun, Lin; Chen, Xiu-Juan; Wang, Na; Yi, Peng-Fei; Song, Min; Zhang, Bo; Wang, Yu-Zhong; Liang, Qiu-Hua

    2016-01-01

    Vascular calcification is an active process of osteoblastic differentiation of vascular smooth muscle cells; however, its definite mechanism remains unknown. Vinpocetine, a derivative of the alkaloid vincamine, has been demonstrated to inhibit the high glucose-induced proliferation of vascular smooth muscle cells; however, it remains unknown whether vinpocetine can affect the osteoblastic differentiation of vascular smooth muscle cells. We hereby investigated the effect of vinpocetine on vascular calcification using a beta-glycerophosphate-induced cell model. Our results showed that vinpocetine significantly reduced the osteoblast-like phenotypes of vascular smooth muscle cells including ALP activity, osteocalcin, collagen type I, Runx2 and BMP-2 expression as well as the formation of mineralized nodule. Vinpocetine, binding to translocation protein, induced phosphorylation of extracellular signal-related kinase and Akt and thus inhibited the translocation of nuclear factor-kappa B into the nucleus. Silencing of translocator protein significantly attenuated the inhibitory effect of vinpocetine on osteoblastic differentiation of vascular smooth muscle cells. Taken together, vinpocetine may be a promising candidate for the clinical therapy of vascular calcification.

  8. Vascular heterogeneity in the kidney.

    PubMed

    Molema, Grietje; Aird, William C

    2012-03-01

    Blood vessels and their endothelial lining are uniquely adapted to the needs of the underlying tissue. The structure and function of the vasculature varies both between and within different organs. In the kidney, the vascular architecture is designed to function both in oxygen/nutrient delivery and filtration of blood according to the homeostatic needs of the body. Here, we review spatial and temporal differences in renal vascular phenotypes in both health and disease. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. VEGF (Vascular Endothelial Growth Factor) and Fibrotic Lung Disease.

    PubMed

    Barratt, Shaney L; Flower, Victoria A; Pauling, John D; Millar, Ann B

    2018-04-24

    Interstitial lung disease (ILD) encompasses a group of heterogeneous diseases characterised by varying degrees of aberrant inflammation and fibrosis of the lung parenchyma. This may occur in isolation, such as in idiopathic pulmonary fibrosis (IPF) or as part of a wider disease process affecting multiple organs, such as in systemic sclerosis. Anti-Vascular Endothelial Growth Factor (anti-VEGF) therapy is one component of an existing broad-spectrum therapeutic option in IPF (nintedanib) and may become part of the emerging therapeutic strategy for other ILDs in the future. This article describes our current understanding of VEGF biology in normal lung homeostasis and how changes in its bioavailability may contribute the pathogenesis of ILD. The complexity of VEGF biology is particularly highlighted with an emphasis on the potential non-vascular, non-angiogenic roles for VEGF in the lung, in both health and disease.

  10. Joint Global War on Terror (GWOT) Vascular Injury Study 2

    DTIC Science & Technology

    2017-02-01

    trauma, vascular injury management, survey , OIF, OEF, Iraq, Afghanistan, Iraq, deployment, training 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...injury, extremity, vascular injury, vascular trauma, vascular injury management, survey , OIF, OEF, Iraq, Afghanistan, Iraq, deployment, training...Phase II will be analyzed to provide comprehensive descriptive information on the patient cohort pertaining to demographics, injury information and

  11. The vascular basement membrane in the healthy and pathological brain.

    PubMed

    Thomsen, Maj S; Routhe, Lisa J; Moos, Torben

    2017-10-01

    The vascular basement membrane contributes to the integrity of the blood-brain barrier (BBB), which is formed by brain capillary endothelial cells (BCECs). The BCECs receive support from pericytes embedded in the vascular basement membrane and from astrocyte endfeet. The vascular basement membrane forms a three-dimensional protein network predominantly composed of laminin, collagen IV, nidogen, and heparan sulfate proteoglycans that mutually support interactions between BCECs, pericytes, and astrocytes. Major changes in the molecular composition of the vascular basement membrane are observed in acute and chronic neuropathological settings. In the present review, we cover the significance of the vascular basement membrane in the healthy and pathological brain. In stroke, loss of BBB integrity is accompanied by upregulation of proteolytic enzymes and degradation of vascular basement membrane proteins. There is yet no causal relationship between expression or activity of matrix proteases and the degradation of vascular matrix proteins in vivo. In Alzheimer's disease, changes in the vascular basement membrane include accumulation of Aβ, composite changes, and thickening. The physical properties of the vascular basement membrane carry the potential of obstructing drug delivery to the brain, e.g. thickening of the basement membrane can affect drug delivery to the brain, especially the delivery of nanoparticles.

  12. Nanotechnology in vascular tissue engineering: from nanoscaffolding towards rapid vessel biofabrication.

    PubMed

    Mironov, Vladimir; Kasyanov, Vladimir; Markwald, Roger R

    2008-06-01

    The existing methods of biofabrication for vascular tissue engineering are still bioreactor-based, extremely expensive, laborious and time consuming and, furthermore, not automated, which would be essential for an economically successful large-scale commercialization. The advances in nanotechnology can bring additional functionality to vascular scaffolds, optimize internal vascular graft surface and even help to direct the differentiation of stem cells into the vascular cell phenotype. The development of rapid nanotechnology-based methods of vascular tissue biofabrication represents one of most important recent technological breakthroughs in vascular tissue engineering because it dramatically accelerates vascular tissue assembly and, importantly, also eliminates the need for a bioreactor-based scaffold cellularization process.

  13. Management of bleeding in vascular surgery.

    PubMed

    Chee, Y E; Liu, S E; Irwin, M G

    2016-09-01

    Management of acute coagulopathy and blood loss during major vascular procedures poses a significant haemostatic challenge to anaesthetists. The acute coagulopathy is multifactorial in origin with tissue injury and hypotension as the precipitating factors, followed by dilution, hypothermia, acidemia, hyperfibrinolysis and systemic inflammatory response, all acting as a self-perpetuating spiral of events. The problem is confounded by the high prevalence of antithrombotic agent use in these patients and intraoperative heparin administration. Trials specifically examining bleeding management in vascular surgery are lacking, and much of the literature and guidelines are derived from studies on patients with trauma. In general, it is recommended to adopt permissive hypotension with a restrictive fluid strategy, using a combination of crystalloid and colloid solutions up to one litre during the initial resuscitation, after which blood products should be administered. A restrictive transfusion trigger for red cells remains the mainstay of treatment except for the high-risk patients, where the trigger should be individualized. Transfusion of blood components should be initiated by clinical evidence of coagulopathy such as diffuse microvascular bleeding, and then guided by either laboratory or point-of-care coagulation testing. Prophylactic antifibrinolytic use is recommended for all surgery where excessive bleeding is anticipated. Fibrinogen and prothrombin complex concentrates administration are recommended during massive transfusion, whereas rFVIIa should be reserved until all means have failed. While debates over the ideal resuscitative strategy continue, the approach to vascular haemostasis should be scientific, rational, and structured. As far as possible, therapy should be monitored and goal directed. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Vascular anomalies: classification, imaging characteristics and implications for interventional radiology treatment approaches

    PubMed Central

    Prajapati, H J S; Martin, L G; Patel, T H

    2014-01-01

    The term vascular anomaly represents a broad spectrum of vascular pathology, including proliferating vascular tumours and vascular malformations. While the treatment of most vascular anomalies is multifactorial, interventional radiology procedures, including embolic therapy, sclerotherapy and laser coagulation among others, are playing an increasingly important role in vascular anomaly management. This review discusses the diagnosis and treatment of common vascular malformations, with emphasis on the technique, efficacy and complications of different interventional radiology procedures. PMID:24588666

  15. Value of MRI in three patients with major vascular injuries after laparoscopic cholecystectomy.

    PubMed

    Ragozzino, Alfonso; Lassandro, Francesco; De Ritis, Rosaria; Imbriaco, Massimo

    2007-11-01

    The aim of this study was to describe three cases of major vascular injuries after laparoscopic cholecystectomy depicted on magnetic resonance (MR) examination. Three female patients (mean age, 32 years; range, 22-39 years) were studied with clinical suspicion of bilio-vascular injuries after laparoscopic cholecystectomy. All MR examinations were performed within 24 h after the laparoscopic procedure. MR imaging was evaluated for major vascular injuries involving the arterial and portal venous system, for bile duct discontinuity, presence or absence of biliary dilation, stricture, excision injury, free fluid and collections. In the first patient, a type-IV Bismuth injury with associated intrahepatic bile ducts dilation was observed. Contrast-enhanced MR revealed lack of enhancement in the right hepatic lobe due to occlusion of the right hepatic artery and the right portal branch. This patient underwent right hepatectomy with hepatico-jejunostomy. In the other two cases, no visualization of the right hepatic artery and the right portal branch was observed on MR angiography. In the first case, the patient underwent right hepatectomy; in the second case, because of stable liver condition, the patient was managed conservatively. MR imaging combined with MR angiography and MR cholangiography can be performed emergently in patients with suspicion of bilio-vascular injury after laparoscopic cholecystectomy allowing the simultaneous evaluation of the biliary tree and the hepatic vascular supply that is essential for adequate treatment planning.

  16. Using Digital Image Correlation to Characterize Local Strains on Vascular Tissue Specimens.

    PubMed

    Zhou, Boran; Ravindran, Suraj; Ferdous, Jahid; Kidane, Addis; Sutton, Michael A; Shazly, Tarek

    2016-01-24

    Characterization of the mechanical behavior of biological and engineered soft tissues is a central component of fundamental biomedical research and product development. Stress-strain relationships are typically obtained from mechanical testing data to enable comparative assessment among samples and in some cases identification of constitutive mechanical properties. However, errors may be introduced through the use of average strain measures, as significant heterogeneity in the strain field may result from geometrical non-uniformity of the sample and stress concentrations induced by mounting/gripping of soft tissues within the test system. When strain field heterogeneity is significant, accurate assessment of the sample mechanical response requires measurement of local strains. This study demonstrates a novel biomechanical testing protocol for calculating local surface strains using a mechanical testing device coupled with a high resolution camera and a digital image correlation technique. A series of sample surface images are acquired and then analyzed to quantify the local surface strain of a vascular tissue specimen subjected to ramped uniaxial loading. This approach can improve accuracy in experimental vascular biomechanics and has potential for broader use among other native soft tissues, engineered soft tissues, and soft hydrogel/polymeric materials. In the video, we demonstrate how to set up the system components and perform a complete experiment on native vascular tissue.

  17. Virtual reality: emerging role of simulation training in vascular access.

    PubMed

    Davidson, Ingemar J A; Lok, Charmaine; Dolmatch, Bart; Gallieni, Maurizio; Nolen, Billy; Pittiruti, Mauro; Ross, John; Slakey, Douglas

    2012-11-01

    Evolving new technologies in vascular access mandate increased attention to patient safety; an often overlooked yet valuable training tool is simulation. For the end-stage renal disease patient, simulation tools are effective for all aspects of creating access for peritoneal dialysis and hemodialysis. Based on aviation principles, known as crew resource management, we place equal emphasis on team training as individual training to improve interactions between team members and systems, cumulating in improved safety. Simulation allows for environmental control and standardized procedures, letting the trainee practice and correct mistakes without harm to patients, compared with traditional patient-based training. Vascular access simulators range from suture devices, to pressurized tunneled conduits for needle cannulation, to computer-based interventional simulators. Simulation training includes simulated case learning, root cause analysis of adverse outcomes, and continual update and refinement of concepts. Implementation of effective human to complex systems interaction in end-stage renal disease patients involves a change in institutional culture. Three concepts discussed in this article are as follows: (1) the need for user-friendly systems and technology to enhance performance, (2) the necessity for members to both train and work together as a team, and (3) the team assigned to use the system must test and practice it to a proficient level before safely using the system on patients. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Possible Vascular Injury Due to Screw Eccentricity in Minimally Invasive Total Hip Arthroplasty.

    PubMed

    Singh, Nishant Kumar; Rai, Sanjay Kumar; Rastogi, Amit

    2017-01-01

    Vascular injury during minimally invasive total hip arthroplasty (THA) is uncommon, yet a well-recognized and serious issue. It emerges because of non-visibility of vascular structures proximal to the pelvic bone during reaming, drilling holes, and fixing of screws. Numerous studies have found that screw fixation during cementless THA is beneficial for the initial stability of cup; yet, no anatomical guidelines support angular eccentric screw fixation. In this study, we obtained the pelvic arterial-phase computed tomographic data of thirty eight humans and reconstructed the three-dimensional models of osseous and vessel structures. We performed the surgical simulation to fix these structures with cementless cups and screws with angular eccentricities. The effect of screw eccentricities (angular eccentricities of ±17° and ±34°) on the vascular injury was determined. Measurement between screw and adjoining vessels was performed and analyzed statistically to ascertain a comparative risk study for blood vessels that are not visible during surgery. Authors similarly discussed the significant absence of appreciation of quadrant systems proposed by Wasielewski et al . on eccentric screws. Adjustment of quadrant systems provided by Wasielewski et al . is required for acetabular implants with eccentric holes for fixation of acetabular screws.

  19. Belowground rhizomes in paleosols: The hidden half of an Early Devonian vascular plant

    NASA Astrophysics Data System (ADS)

    Xue, Jinzhuang; Deng, Zhenzhen; Huang, Pu; Huang, Kangjun; Benton, Michael J.; Cui, Ying; Wang, Deming; Liu, Jianbo; Shen, Bing; Basinger, James F.; Hao, Shougang

    2016-08-01

    The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant-soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus. The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils within a seasonal wet-dry climate zone. Rhizome networks contributed to the accumulation and pedogenesis of floodplain sediments and increased the soil stabilizing effects of early plants. Predating the appearance of trees with deep roots in the Middle Devonian, plant rhizomes have long functioned in the belowground soil ecosystem. This study presents strong, direct evidence for plant-soil interactions at an early stage of vascular plant radiation. Soil stabilization by complex rhizome systems was apparently widespread, and contributed to landscape modification at an earlier time than had been appreciated.

  20. Belowground rhizomes in paleosols: The hidden half of an Early Devonian vascular plant.

    PubMed

    Xue, Jinzhuang; Deng, Zhenzhen; Huang, Pu; Huang, Kangjun; Benton, Michael J; Cui, Ying; Wang, Deming; Liu, Jianbo; Shen, Bing; Basinger, James F; Hao, Shougang

    2016-08-23

    The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant-soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils within a seasonal wet-dry climate zone. Rhizome networks contributed to the accumulation and pedogenesis of floodplain sediments and increased the soil stabilizing effects of early plants. Predating the appearance of trees with deep roots in the Middle Devonian, plant rhizomes have long functioned in the belowground soil ecosystem. This study presents strong, direct evidence for plant-soil interactions at an early stage of vascular plant radiation. Soil stabilization by complex rhizome systems was apparently widespread, and contributed to landscape modification at an earlier time than had been appreciated.