WorldWideScience

Sample records for microvascular blood supply

  1. Cholangiocytes and blood supply

    Institute of Scientific and Technical Information of China (English)

    Eugenio Gaudio; Antonio Franchitto; Luigi Pannarale; Guido Carpino; Gianfranco Alpini; Heather Francis; Shannon Glaser; Domenico Alvaro; Paolo Onori

    2006-01-01

    The microvascular supply of the biliary tree, the peribiliary plexus (PBP), stems from the hepatic artery branches and flows into the hepatic sinusoids. A detailed three-dimensional study of the PBP has been performed by using the Scanning Electron Microscopy vascular corrosion casts (SEMvcc) technique. Considering that the PBP plays a fundamental role in supporting the secretory and absorptive functions of the biliary epithelium, their organization in either normalcy and pathology is explored. The normal liver shows the PBP arranged around extra- and intrahepatic biliary tree.In the small portal tract PBP was characterized by a single layer of capillaries which progressively continued with the extrahepatic PBP where it showed a more complex vascular network. After common duct ligation (BDL), progressive modifications of bile duct and PBP proliferation are observed. The PBP presents a threedimensional network arranged around many bile ducts and appears as bundles of vessels, composed by capillaries of homogeneous diameter with a typical round mesh structure. The PBP network is easily distinguishable from the sinusoidal network which appears normal. Considering the enormous extension of the PBP during BDL, the possible role played by the Vascular Endothelial Growth Factor (VEGF) is evaluated. VEGF-A,VEGF-C and their related receptors appeared highly immunopositive in proliferating cholangiocytes of BDL rats. The administration of anti-VEGF-A or anti-VEGF-C antibodies to BDL rats as well as hepatic artery ligation induced a reduced bile duct mass. The administration of rVEGF-A to BDL hepatic artery ligated rats prevented the decrease of cholangiocyte proliferation and VEGF-A expression as compared to BDL control rats. These data suggest the role of arterial blood supply of the biliary tree in conditions of cholangiocyte proliferation, such as it occurs during chronic cholestasis. On the other hand,the role played by VEGF as a tool of cross-talk between cholangiocytes

  2. Blood-based biomarkers of microvascular pathology in Alzheimer's disease.

    LENUS (Irish Health Repository)

    Ewers, Michael

    2012-02-01

    Sporadic Alzheimer\\'s disease (AD) is a genetically complex and chronically progressive neurodegenerative disorder with molecular mechanisms and neuropathologies centering around the amyloidogenic pathway, hyperphosphorylation and aggregation of tau protein, and neurofibrillary degeneration. While cerebrovascular changes have not been traditionally considered to be a central part of AD pathology, a growing body of evidence demonstrates that they may, in fact, be a characteristic feature of the AD brain as well. In particular, microvascular abnormalities within the brain have been associated with pathological AD hallmarks and may precede neurodegeneration. In vivo assessment of microvascular pathology provides a promising approach to develop useful biological markers for early detection and pathological characterization of AD. This review focuses on established blood-based biological marker candidates of microvascular pathology in AD. These candidates include plasma concentration of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) that are increased in AD. Measures of endothelial vasodilatory function including endothelin (ET-1), adrenomedullin (ADM), and atrial natriuretic peptide (ANP), as well as sphingolipids are significantly altered in mild AD or during the predementia stage of mild cognitive impairment (MCI), suggesting sensitivity of these biomarkers for early detection and diagnosis. In conclusion, the emerging clinical diagnostic evidence for the value of blood-based microvascular biomarkers in AD is promising, however, still requires validation in phase II and III diagnostic trials. Moreover, it is still unclear whether the described protein dysbalances are early or downstream pathological events and how the detected systemic microvascular alterations relate to cerebrovascular and neuronal pathologies in the AD brain.

  3. Spontaneous oscillations of capillary blood flow in artificial microvascular networks.

    Science.gov (United States)

    Forouzan, Omid; Yang, Xiaoxi; Sosa, Jose M; Burns, Jennie M; Shevkoplyas, Sergey S

    2012-09-01

    Previous computational studies have suggested that the capillary blood flow oscillations frequently observed in vivo can originate spontaneously from the non-linear rheological properties of blood, without any regulatory input. Testing this hypothesis definitively in experiments involving real microvasculature has been difficult because in vivo the blood flow in capillaries is always actively controlled by the host. The objective of this study was to test the hypothesis experimentally and to investigate the relative contribution of different blood cells to the capillary blood flow dynamics under static boundary conditions and in complete isolation from the active regulatory mechanisms mediated by the blood vessels in vivo. To accomplish this objective, we passed whole blood and re-constituted blood samples (purified red blood cells suspended in buffer or in autologous plasma) through an artificial microvascular network (AMVN) comprising completely inert, microfabricated vessels with the architecture inspired by the real microvasculature. We found that the flow of blood in capillaries of the AMVN indeed oscillates with characteristic frequencies in the range of 0-0.6 Hz, which is in a very good agreement with previous computational studies and in vivo observations. We also found that the traffic of leukocytes through the network (typically neglected in computational modeling) plays an important role in generating the oscillations. This study represents the key piece of experimental evidence in support of the hypothesis that spontaneous, self-sustained oscillations of capillary blood flow can be generated solely by the non-linear rheological properties of blood flowing through microvascular networks, and provides an insight into the mechanism of this fundamentally important microcirculatory phenomenon.

  4. Optically measured microvascular blood flow contrast of malignant breast tumors.

    Directory of Open Access Journals (Sweden)

    Regine Choe

    Full Text Available Microvascular blood flow contrast is an important hemodynamic and metabolic parameter with potential to enhance in vivo breast cancer detection and therapy monitoring. Here we report on non-invasive line-scan measurements of malignant breast tumors with a hand-held optical probe in the remission geometry. The probe employs diffuse correlation spectroscopy (DCS, a near-infrared optical method that quantifies deep tissue microvascular blood flow. Tumor-to-normal perfusion ratios are derived from thirty-two human subjects. Mean (95% confidence interval tumor-to-normal ratio using surrounding normal tissue was 2.25 (1.92-2.63; tumor-to-normal ratio using normal tissues at the corresponding tumor location in the contralateral breast was 2.27 (1.94-2.66, and using normal tissue in the contralateral breast was 2.27 (1.90-2.70. Thus, the mean tumor-to-normal ratios were significantly different from unity irrespective of the normal tissue chosen, implying that tumors have significantly higher blood flow than normal tissues. Therefore, the study demonstrates existence of breast cancer contrast in blood flow measured by DCS. The new, optically accessible cancer contrast holds potential for cancer detection and therapy monitoring applications, and it is likely to be especially useful when combined with diffuse optical spectroscopy/tomography.

  5. Hepatic arteriolo-portal venular shunting guarantees maintenance of nutritional microvascular supply in hepatic arterial buffer response of rat livers.

    Science.gov (United States)

    Richter, S; Vollmar, B; Mücke, I; Post, S; Menger, M D

    2001-02-15

    To elucidate the hepatic microvascular response upon the hepatic arterial buffer response (HABR), we analysed blood flow (ultrasonic flowprobes) of the hepatic artery (HA) and portal vein (PV), microcirculation (intravital microscopy), and tissue oxygenation (polarography) in anaesthetized Sprague-Dawley rats and re-evaluated the role of adenosine in mediating the HABR by using 8-phenyltheophylline as a competitive antagonist. 2. Upon restriction of PV blood flow to 11 +/- 3 % of baseline values, HA blood flow increased by a factor of 1.77 (P portal venules (TPVs) decreased to only 66 % (P portal venular shunting. As a consequence, red blood cell velocity and volumetric blood flow in sinusoids were found to be reduced to only 66-68 % compared with baseline (P oxygen delivery, despite the marked reduction of total liver blood flow. Further, hepatic arteriolo-portal venular shunting guaranteed homogeneity of nutritive blood flow upon HABR, as given by an unchanged intra-acinar coefficient of variance of sinusoidal perfusion. 4. Pretreatment of animals with the adenosine antagonist 8-phenyltheophylline completely blocked the hepatic arterial buffer response with the consequence of decreased tissue oxygenation and increased heterogeneity of sinusoidal perfusion. 5. In conclusion, hepatic microhaemodynamics, in particular unchanged diameters of THAs, TPVs and sinusoids, during HABR indicate that reduction in resistance to HA flow is located upstream and functions via hepatic arteriolo-portal venular shunts resulting in equal distribution of microvascular blood flow and oxygen delivery under conditions of restricted PV blood supply.

  6. Quantitative and qualitative retinal microvascular characteristics and blood pressure.

    Science.gov (United States)

    Cheung, Carol Y; Tay, Wan T; Mitchell, Paul; Wang, Jie J; Hsu, Wynne; Lee, Mong L; Lau, Qiangfeng P; Zhu, Ai L; Klein, Ronald; Saw, Seang M; Wong, Tien Y

    2011-07-01

    The present study examined the effects of blood pressure on a spectrum of quantitative and qualitative retinal microvascular signs. Retinal photographs from the Singapore Malay Eye Study, a population-based cross-sectional study of 3280 (78.7% response) persons aged 40-80 years, were analyzed. Quantitative changes in the retinal vasculature (branching angle, vascular tortuosity, fractal dimension, and vascular caliber) were measured using a semi-automated computer-based program. Qualitative signs, including focal arteriolar narrowing (FAN), arteriovenous nicking (AVN), opacification of the arteriolar wall (OAW), and retinopathy (e.g., microaneurysms, retinal hemorrhages), were assessed from photographs by trained technicians. After excluding persons with diabetes and ungradable photographs, 1913 persons provided data for this analysis. In multivariable linear regression models controlling for age, sex, BMI, use of antihypertensive medication, and other factors, retinal arteriolar branching asymmetry ratio, arteriolar tortuosity, venular tortuosity, fractal dimension, arteriolar caliber, venular caliber, FAN, AVN, and retinopathy were independently associated with mean arterial blood pressure. In contrast, arteriolar/venular branching angle, venular branching asymmetry ratio and OAW were not related to blood pressure. Retinal arteriolar caliber (sβ = -0.277) and FAN (sβ = 0.170) had the strongest associations with mean arterial blood pressure, and higher blood pressure levels were associated with increasing number of both quantitative and qualitative retinal vascular signs (P trend qualitative retinal vascular signs, with the number of signs increasing with higher blood pressure levels.

  7. Holographic laser Doppler imaging of microvascular blood flow

    CERN Document Server

    Magnain, C; Boucneau, T; Simonutti, M; Ferezou, I; Rancillac, A; Vitalis, T; Sahel, J A; Paques, M; Atlan, M

    2014-01-01

    We report on local superficial blood flow monitoring in biological tissue from laser Doppler holographic imaging. In time averaging recording conditions, holography acts as a narrowband bandpass filter, which, combined with a frequency shifted reference beam, permits frequency selective imaging in the radiofrequency range. These Doppler images are acquired with an off axis Mach Zehnder interferometer. Microvascular hemodynamic components mapping is performed in the cerebral cortex of the mouse and the eye fundus of the rat with near-infrared laser light without any exogenous marker. These measures are made from a basic inverse method analysis of local first order optical fluctuation spectra at low radiofrequencies, from 0 Hz to 100 kHz. Local quadratic velocity is derived from Doppler broadenings induced by fluid flows, with elementary diffusing wave spectroscopy formalism in backscattering configuration. We demonstrate quadratic mean velocity assessment in the 0.1 to 10 millimeters per second range in vitro ...

  8. Microvascular function relates to insulin sensitivity and blood pressure in normal subjects

    NARCIS (Netherlands)

    Serne, EH; Stehouwer, CDA; ter Maaten, JC; ter Wee, PM; Rauwerda, JA; Gans, ROB

    1999-01-01

    Background-A strong but presently unexplained inverse association between blood pressure and insulin sensitivity has been reported. Microvascular vasodilator capacity may be a common antecedent linking insulin sensitivity to blood pressure. To test this hypothesis, we studied LX normotensive and glu

  9. Electrical cardioversion for atrial fibrillation improves microvascular flow independent of blood pressure changes.

    Science.gov (United States)

    Elbers, Paul W G; Prins, Wilhelmina B; Plokker, Herbert W M; van Dongen, Eric P A; van Iterson, Mat; Ince, Can

    2012-10-01

    This study tested the hypothesis that there is a discrepancy between global hemodynamic parameters and microvascular flow in patients before and after successful elective electrical cardioversion (ECV) for atrial fibrillation (AF). Prospective observational study. Preanesthesia holding area in a teaching hospital. Adult patients who underwent successful elective ECV for AF. ECV. Routine measurements of heart rate and noninvasive blood pressure were recorded and the sublingual microcirculation was visualized by sidestream darkfield imaging before and after the conversion of AF to sinus rhythm by elective ECV. The conversion to sinus rhythm significantly improved the microvascular flow index for smaller and larger microvessels. For smaller microvessels, perfused vessel density did not reach significance after conversion to sinus rhythm, whereas the proportion of perfused vessels was significantly larger and indices of heterogeneity for microvascular flow index decreased significantly. No correlation could be identified for the changes in mean blood pressure, perfused vessel density, and microvascular flow index for smaller microvessels. Successful ECV in patients with AF improves indices of sublingual microvascular perfusion. This change has no clear relation to the change in blood pressure and cannot be predicted from it. It may be prudent not to rely solely on global hemodynamic parameters to assess end-organ perfusion in this setting. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Birth weight relates to blood pressure and microvascular function in normal subjects

    NARCIS (Netherlands)

    Serne, EH; Stehouwer, CDA; ter Maaten, JC; ter Wee, PM; Gans, ROB

    2000-01-01

    Objective The relationship between low birth weight and elevated blood pressure in adult life is well established but presently unexplained. Both microvascular dysfunction and insulin resistance have been proposed as a possible explanation. We have examined the relation between birth weight and bloo

  11. Microvascular Blood Flow Improvement in Hyperglycemic Obese Adult Patients by Hypocaloric Diet

    OpenAIRE

    Mastantuono, T; Di Maro, M.; Chiurazzi, M.; Battiloro, L.; Starita, N.; Nasti, G; Lapi, D.; Iuppariello, L.; M. Cesarelli; D’Addio, G.; Colantuoni, A.

    2016-01-01

    The present study was aimed to assess the changes in skin microvascular blood flow (SBF) in newly diagnosed hyperglycemic obese subjects, administered with hypocaloric diet. Adult patients were recruited and divided in three groups: NW group (n=54), NG (n=54) and HG (n=54) groups were constituted by normal weight, normoglycemic and hyperglycemic obese subjects, respectively. SBF was measured by laser Doppler perfusion monitoring technique and oscillations in blood flow were analyzed by spectr...

  12. Absolute coronary blood flow measurement and microvascular resistance in ST-elevation myocardial infarction in the acute and subacute phase

    Energy Technology Data Exchange (ETDEWEB)

    Wijnbergen, Inge; Veer, Marcel van ' t [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands); Lammers, Jeroen; Ubachs, Joey [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Pijls, Nico H.J., E-mail: nico.pijls@cze.nl [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands)

    2016-03-15

    Background/Purpose: In a number of patients with acute myocardial infarction (AMI), myocardial hypoperfusion, known as the no-reflow phenomenon, persists after primary percutaneous intervention (PPCI). The aim of this study was to evaluate the feasibility and safety of a new quantitative method of measuring absolute blood flow and resistance within the perfusion bed of an infarct-related artery. Furthermore, we sought to study no-reflow by correlating these measurements to the index of microvascular resistance (IMR) and the area at risk (AR) as determined by cardiac magnetic resonance imaging (CMR). Methods: Measurements of absolute flow and myocardial resistance were performed in 20 patients with ST-segment elevation myocardial infarction (STEMI), first immediately following PPCI and then again after 3–5 days. These measurements used the technique of thermodilution during a continuous infusion of saline. Flow was expressed in ml/min per gram of tissue within the area at risk. Results: The average time needed for measurement of absolute flow, resistance and IMR was 20 min, and all measurements could be performed without complication. A higher flow supplying the AR correlated with a lower IMR in the acute phase. Absolute flow increased from 3.14 to 3.68 ml/min/g (p = 0.25) and absolute resistance decreased from 1317 to 1099 dyne.sec.cm-5/g (p = 0.40) between the first day and fifth day after STEMI. Conclusions: Measurement of absolute flow and microvascular resistance is safe and feasible in STEMI patients and may allow for a better understanding of microvascular (dys)function in the early phase of AMI. - Highlights: • We measured absolute coronary blood flow and microvascular resistance in STEMI patients in the acute phase and in the subacute phase, using the technique of thermodilution with low grade intracoronary continuous infusion of saline. • These measurements are safe and feasible during PPCI in STEMI patients. • In STEMI patients, absolute flow

  13. Microvascular blood flow resistance: Role of red blood cell migration and dispersion.

    Science.gov (United States)

    Katanov, Dinar; Gompper, Gerhard; Fedosov, Dmitry A

    2015-05-01

    Microvascular blood flow resistance has a strong impact on cardiovascular function and tissue perfusion. The flow resistance in microcirculation is governed by flow behavior of blood through a complex network of vessels, where the distribution of red blood cells across vessel cross-sections may be significantly distorted at vessel bifurcations and junctions. In this paper, the development of blood flow and its resistance starting from a dispersed configuration of red blood cells is investigated in simulations for different hematocrit levels, flow rates, vessel diameters, and aggregation interactions between red blood cells. Initially dispersed red blood cells migrate toward the vessel center leading to the formation of a cell-free layer near the wall and to a decrease of the flow resistance. The development of cell-free layer appears to be nearly universal when scaled with a characteristic shear rate of the flow. The universality allows an estimation of the length of a vessel required for full flow development, lc ≲ 25D, for vessel diameters in the range 10 μm red blood cell dispersion at vessel bifurcations and junctions on the flow resistance may be significant in vessels which are shorter or comparable to the length lc. Aggregation interactions between red blood cells generally lead to a reduction of blood flow resistance. The simulations are performed using the same viscosity for both external and internal fluids and the RBC membrane viscosity is not considered; however, we discuss how the viscosity contrast may affect the results. Finally, we develop a simple theoretical model which is able to describe the converged cell-free-layer thickness at steady-state flow with respect to flow rate. The model is based on the balance between a lift force on red blood cells due to cell-wall hydrodynamic interactions and shear-induced effective pressure due to cell-cell interactions in flow. We expect that these results can also be used to better understand the flow

  14. Red blood cell count as an indicator of microvascular complications in Chinese patients with type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Wang ZS

    2013-05-01

    Full Text Available Zhan-Sheng Wang,1,2 Zhan-Chun Song,1 Jing-Hui Bai,1 Fei Li,3 Tao Wu,1 Ji Qi,2 Jian Hu11Department of Cardiology, First Affiliated Hospital of China Medical University, 2Second Department of Cardiology, Fourth People's Hospital of Shenyang, Shenyang, 3Department of Cardiology, Shenzhou Hospital of Shenyang Medical College, Shenyang, People's Republic of ChinaBackground: Rheological disorders of red blood cells (RBC and decreased RBC deformability have been involved in the development of diabetic microangiopathy. However, few studies have evaluated the association of RBC count with microvascular complications in patients with type 2 diabetes mellitus (T2DM. The purpose of this study was to investigate the association of RBC count with microvascular complications in patients with T2DM.Methods: This study involved 369 patients with T2DM: 243 with one or more microvascular complications and 126 without microvascular complications. Anticoagulated blood was collected and analyzed in an automated blood cell counter. The presence of risk factors for microvascular complications was determined.Results: The proportion of patients with microvascular complications increased as the RBC count decreased (P < 0.001. After adjustment for known risk factors for microvascular complications by logistic regression analysis, lower quartiles of RBC count were associated with a higher risk of microvascular complications compared with the reference group composed of the highest quartile (first quartile, odds ratio 4.98, 95% confidence interval 1.54–6.19, P = 0.008; second quartile, odds ratio 3.21, 95% confidence interval 1.17–5.28, P = 0.024.Conclusion: A decreased RBC count is associated with microvascular complications in Chinese patients with T2DM. The RBC count is a potential marker to improve further the ability to identify diabetic patients at high risk of microvascular complications.Keywords: red blood cell count, microvascular complication, type 2 diabetes

  15. Forecasting Ontario's blood supply and demand.

    Science.gov (United States)

    Drackley, Adam; Newbold, K Bruce; Paez, Antonio; Heddle, Nancy

    2012-02-01

    Given an aging population that requires increased medical care, an increasing number of deferrals from the donor pool, and a growing immigrant population that typically has lower donation rates, the purpose of this article is to forecast Ontario's blood supply and demand. We calculate age- and sex-specific donation and demand rates for blood supply based on 2008 data and project demand between 2008 and 2036 based on these rates and using population data from the Ontario Ministry of Finance. Results indicate that blood demand will outpace supply as early as 2012. For instance, while the total number of donations made by older cohorts is expected to increase in the coming years, the number of red blood cell (RBC) transfusions in the 70+ age group is forecasted grow from approximately 53% of all RBC transfusions in 2008 (209,515) in 2008 to 68% (546,996) by 2036. A series of alternate scenarios, including projections based on a 2% increase in supply per year and increased use of apheresis technology, delays supply shortfalls, but does not eliminate them without active management and/or multiple methods to increase supply and decrease demand. Predictions show that demand for blood products will outpace supply in the near future given current age- and sex-specific supply and demand rates. However, we note that the careful management of the blood supply by Canadian Blood Services, along with new medical techniques and the recruitment of new donors to the system, will remove future concerns. © 2012 American Association of Blood Banks.

  16. 21 CFR 864.9050 - Blood bank supplies.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood bank supplies. 864.9050 Section 864.9050... and Blood Products § 864.9050 Blood bank supplies. (a) Identification. Blood bank supplies are general... such as blood bank pipettes, blood grouping slides, blood typing tubes, blood typing racks, and...

  17. A reduced gastric corpus microvascular blood flow during Ivor-Lewis esophagectomy detected by laser speckle contrast imaging technique

    DEFF Research Database (Denmark)

    Ambrus, Rikard; Svendsen, Lars B; Secher, Niels H

    2017-01-01

    BACKGROUND: Reduced microvascular blood flow is related to anastomotic insufficiency following esophagectomy, emphasizing a need for intraoperative monitoring of the microcirculation. This study evaluated if laser speckle contrast imaging (LSCI) was able to detect intraoperative changes in gastric...

  18. Diabetes augments in vivo microvascular blood flow dynamics after stroke.

    Science.gov (United States)

    Tennant, Kelly A; Brown, Craig E

    2013-12-04

    Stroke usually affects people with underlying medical conditions. In particular, diabetics are significantly more likely to have a stroke and the prognosis for recovery is poor. Because diabetes is associated with degenerative changes in the vasculature of many organs, we sought to determine how hyperglycemia affects blood flow dynamics after an ischemic stroke. Longitudinal in vivo two-photon imaging was used to track microvessels before and after photothrombotic stroke in a diabetic mouse model. Chronic hyperglycemia exacerbated acute (3-7 d) ischemia-induced increases in blood flow velocity, vessel lumen diameter, and red blood cell flux in peri-infarct regions. These changes in blood flow dynamics were most evident in superficial blood vessels within 500 μm from the infarct, rather than deeper or more distant cortical regions. Long-term imaging of diabetic mice not subjected to stroke indicated that these acute stroke-related changes in vascular function could not be attributed to complications from hyperglycemia alone. Treating diabetic mice with insulin immediately after stroke resulted in less severe alterations in blood flow within the first 7 d of recovery, but had more variable results at later time points. Analysis of microvessel branching patterns revealed that stroke led to a pruning of microvessels in peri-infarct cortex, with very few instances of sprouting. These results indicate that chronic hyperglycemia significantly affects the vascular response to ischemic stroke and that insulin only partially mitigates these changes. The combination of these acute and chronic alterations in blood flow dynamics could underlie diabetes-related deficits in cortical plasticity and stroke recovery.

  19. Sympathetically-induced changes in microvascular cerebral blood flow and in the morphology of its low-frequency waves.

    Science.gov (United States)

    Deriu, F; Roatta, S; Grassi, C; Urciuoli, R; Micieli, G; Passatore, M

    1996-06-10

    The effect of bilateral cervical sympathetic nerve stimulation on microvascular cerebral blood flow, recorded at various depths in the parietal lobe and in ponto-mesencephalic areas, was investigated by laser-Doppler flowmetry in normotensive rabbits. These areas were chosen as representative of the vascular beds supplied by the carotid and vertebro-basilar systems, which exhibit different degrees of sympathetic innervation, the former being richer than the latter. Sympathetic stimulation at 30 imp/s affects cerebral blood flow in 77% of the parietal lobe and in 43% of the ponto-mesencephalic tested areas. In both cases the predominant effect was a reduction in blood flow (14.7 +/- 5.1% and 4.1 +/- 2.4%, respectively). The extent of the reduction in both areas was less if the stimulation frequency was decreased. Sometimes mean cerebral blood flow showed a small and transient increase, mainly in response to low-frequency stimulation. The morphology was analysed of low-frequency spontaneous oscillations in cerebral blood flow, attributed to vasomotion. Present in 41% of the tested areas (frequency 4-12 cycles/min, peak-to-peak amplitude 10-40% of mean value), these waves decreased in amplitude and increased in frequency during sympathetic stimulation, irrespective of changes in mean flow. The possibility has been proposed that the sympathetic action on low-frequency spontaneous oscillations may contribute to the protective influence that this system is known to exert on the blood-brain barrier in hypertension.

  20. Absolute coronary blood flow measurement and microvascular resistance in ST-elevation myocardial infarction in the acute and subacute phase.

    Science.gov (United States)

    Wijnbergen, Inge; van 't Veer, Marcel; Lammers, Jeroen; Ubachs, Joey; Pijls, Nico H J

    2016-03-01

    In a number of patients with acute myocardial infarction (AMI), myocardial hypoperfusion, known as the no-reflow phenomenon, persists after primary percutaneous intervention (PPCI). The aim of this study was to evaluate the feasibility and safety of a new quantitative method of measuring absolute blood flow and resistance within the perfusion bed of an infarct-related artery. Furthermore, we sought to study no-reflow by correlating these measurements to the index of microvascular resistance (IMR) and the area at risk (AR) as determined by cardiac magnetic resonance imaging (CMR). Measurements of absolute flow and myocardial resistance were performed in 20 patients with ST-segment elevation myocardial infarction (STEMI), first immediately following PPCI and then again after 3-5days. These measurements used the technique of thermodilution during a continuous infusion of saline. Flow was expressed in ml/min per gram of tissue within the area at risk. The average time needed for measurement of absolute flow, resistance and IMR was 20min, and all measurements could be performed without complication. A higher flow supplying the AR correlated with a lower IMR in the acute phase. Absolute flow increased from 3.14 to 3.68ml/min/g (p=0.25) and absolute resistance decreased from 1317 to 1099 dyne.sec.cm-5/g (p=0.40) between the first day and fifth day after STEMI. Measurement of absolute flow and microvascular resistance is safe and feasible in STEMI patients and may allow for a better understanding of microvascular (dys)function in the early phase of AMI. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Microvascular blood flow and skin temperature changes in the fingers following a deep nspiratory gasp.

    Science.gov (United States)

    Allen, John; Frame, John R; Murray, Alan

    2002-05-01

    The aims of this study were to quantify the changes in finger pulp skin temperature, laser Doppler flow (LDF, microvascular flux) and photoplethysmogram (PPG, microvascular blood volume pulsatility), induced by a deep inspiration in healthy subjects, and to investigate the repeatability of these responses within a measurement session and between measurement sessions on separate days. A system comprising an electronic thermometer, a laser Doppler flowmeter and a PPG amplifier measured simultaneous vasoconstrictor responses to a deep inspiratory gasp from three adjacent fingers of one hand. Clearly defined responses were obtained in 15 of the 17 subjects studied. Skin temperature fell in all of these subjects after each gasp, with a median fall of 0.089 degrees C (P < 0.001). The median value of LDF flux reduction was 93% (P < 0.001) indicating a momentary almost complete shut-down of microvascular blood flow; and PPG also showed a large response relative to pulse amplitude of 2.6 (P < 0.001). The median times for waveforms to reach their minimum were 4.6 s (PPG), 6.3 s (LDF) and 29.1 s (skin pulp temperature), with median delays between minima of LDF and PPG of 1.6 s (P < 0.001) and skin temperature and PPG of 23.5 s (P < 0.001). The vascular responses of skin temperature, LDF and PPG to an inspiratory gasp were repeatable, with temperature change repeatable to within 10% of the median subject change.

  2. Cutaneous iontophoresis of treprostinil, a prostacyclin analog, increases microvascular blood flux in diabetic malleolus area.

    Science.gov (United States)

    Hellmann, Marcin; Roustit, Matthieu; Gaillard-Bigot, Florence; Cracowski, Jean-Luc

    2015-07-05

    Diabetic foot ulcers are one of the most common and serious complications of diabetes mellitus. Few drugs are effective in enhancing the healing of microvascular skin ulcers. The main objective of the present study was to determine whether iontophoresis of treprostinil, a prostacyclin analog, increases skin microvascular blood flux in the malleolus area of healthy subjects and diabetic patients. We recruited 12 healthy subjects and 12 type 2 diabetic patients. Cathodal iontophoresis (40mC/cm²) of treprostinil 250µM and NaCl 0.9% was performed in the malleolus area. Skin hyperemia was quantified using non-invasive laser speckle contrast imaging, and expressed as the area under the curve (AUC) of cutaneous vascular conductance (CVC). In healthy controls and diabetic patients, treprostinil 250µM induced a significant increase in CVC compared with NaCl (for diabetic patients, AUC0-6h was 19970±8697; versus 2893±5481%BL.min, respectively; P=0.002). In both groups, the peak flux was obtained between 30min and 1h after the end of treprostinil iontophoresis and flux remained higher than baseline up to 6h after ending of iontophoresis. No significant side-effect occurred. Cutaneous iontophoresis of 250µM treprostinil increases microvascular blood flux in the malleolus area in healthy volunteers and diabetic patients, without inducing systemic or local side-effects. Treprostinil cathodal iontophoresis should be further investigated as a new local therapy for diabetic ulcers.

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

    Institute of Scientific and Technical Information of China (English)

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

    2006-01-01

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

  4. Quantification of coronary microvascular resistance using angiographic images for volumetric blood flow measurement: in vivo validation.

    Science.gov (United States)

    Zhang, Zhang; Takarada, Shigeho; Molloi, Sabee

    2011-06-01

    Structural coronary microcirculation abnormalities are important prognostic determinants in clinical settings. However, an assessment of microvascular resistance (MR) requires a velocity wire. A first-pass distribution analysis technique to measure volumetric blood flow has been previously validated. The aim of this study was the in vivo validation of the MR measurement technique using first-pass distribution analysis. Twelve anesthetized swine were instrumented with a transit-time ultrasound flow probe on the proximal segment of the left anterior descending coronary artery (LAD). Microspheres were injected into the LAD to create a model of microvascular dysfunction. Adenosine (400 μg·kg(-1)·min(-1)) was used to produce maximum hyperemia. A region of interest in the LAD arterial bed was drawn to generate time-density curves using angiographic images. Volumetric blood flow measurements (Q(a)) were made using a time-density curve and the assumption that blood was momentarily replaced with contrast agent during the injection. Blood flow from the flow probe (Q(p)), coronary pressure (P(a)), and right atrium pressure (P(v)) were continuously recorded. Flow probe-based normalized MR (NMR(p)) and angiography-based normalized MR (NMR(a)) were calculated using Q(p) and Q(a), respectively. In 258 measurements, Q(a) showed a strong correlation with the gold standard Q(p) (Q(a) = 0.90 Q(p) + 6.6 ml/min, r(2) = 0.91, P measure NMR without using a velocity wire, which can potentially be used to evaluate microvascular conditions during coronary arteriography.

  5. Administration of Traditional Chinese Blood Circulation Activating Drugs for Microvascular Complications in Patients with Type 2 Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    Lisha He

    2016-01-01

    Full Text Available Traditional Chinese medicine (TCM is an important complementary strategy for treating diabetes mellitus (DM in China. Traditional Chinese blood circulation activating drugs are intended to guide an overall approach to the prevention and treatment of microvascular complications of DM. The core mechanism is related to the protection of the vascular endothelium and the basement membrane. Here, we reviewed the scientific evidence underpinning the use of blood circulation activating drugs to prevent and treat DM-induced microvascular complications, including diabetic nephropathy (DN, diabetic peripheral neuropathy (DPN, and diabetic retinopathy (DR. Furthermore, we summarized the effects and mechanism of TCM on improving blood rheology, inhibiting aggregation of platelet, forming advanced glycation end products (AGEs, regulating oxidative stress, reducing blood fat, and improving lipid metabolism. The paper provides a new theoretical basis for the clinical practice of TCM in the prevention and treatment of DM and its microvascular complications.

  6. Laser speckle contrast imaging for monitoring changes in microvascular blood flow

    DEFF Research Database (Denmark)

    Ambrus, Rikard; Strandby, Rune B.; Svendsen, Lars Bo;

    2016-01-01

    BACKGROUND/AIMS: Microvascular blood flow is essential for healing and predicts surgical outcome. The aim of the current study was to investigate the relation between fluxes measured with the laser speckle contrast imaging (LSCI) technique and changes in absolute blood flow. In addition, we studied...... the reproducibility of the LSCI technique when assessing the intra-abdominal microcirculation of the pig. METHODS: During trial 1, a fish gill arch was mechanically perfused with heparinized fish blood under controlled stepwise-altered flow rates alongside mechanically induced movement artefacts. The microcirculation...... = 6.0, 3.2, and 6.4%, respectively). CONCLUSION: Due to the non-contact and real-time assessment over large areas, LSCI is a promising technique for the intraoperative assessment of intra-abdominal microcirculation. A linear correlation between flux and volumetric flow was found, in accordance...

  7. Numerical simulation of red blood cell distributions in three-dimensional microvascular bifurcations.

    Science.gov (United States)

    Hyakutake, Toru; Nagai, Shinya

    2015-01-01

    We constructed three-dimensional microvascular bifurcation models using a parent vessel of diameter 10μm and investigated the flow behavior of the red blood cells (RBCs) through bifurcations. We considered symmetric and asymmetric model types. Two cases of equal daughter vessel diameter were employed for the asymmetric models, where the first was 10μm, which is the same as the parent vessel and the second was 7.94μm, which satisfies Murray's law. Simulated blood flow was computed using the lattice Boltzmann method in conjunction with the immersed boundary method for incorporating fluid-membrane interactions between the flow field and deformable RBCs. First, we investigated the flow behavior of a single RBC through microvascular bifurcations. In the case of the symmetric bifurcation, the turning point of the fractional plasma flow wherein the RBC flow changed from one daughter vessel to the other was 0.50. This turning point was however different for asymmetric bifurcations. Additionally, we varied the initial offset of RBCs from the centerline of the parent vessel. The simulation results indicated that the RBCs preferentially flow through the branch of a larger flow ratio. Next, we investigated the distribution characteristics of multiple RBCs. Simulations indicated that the results of the symmetric model were similar to those predicted by a previously published empirical model. On the other hand, results of asymmetric models deviated from those of the symmetric and empirical models. These results suggest that the distribution of RBCs varies according to the bifurcation angle and daughter vessel diameter in a microvascular bifurcation of the size considered.

  8. The relationship between red blood cell deformability metrics and perfusion of an artificial microvascular network.

    Science.gov (United States)

    Sosa, Jose M; Nielsen, Nathan D; Vignes, Seth M; Chen, Tanya G; Shevkoplyas, Sergey S

    2014-01-01

    The ability of red blood cells (RBC) to undergo a wide range of deformations while traversing the microvasculature is crucial for adequate perfusion. Interpretation of RBC deformability measurements performed in vitro in the context of microvascular perfusion has been notoriously difficult. This study compares the measurements of RBC deformability performed using micropore filtration and ektacytometry with the RBC ability to perfuse an artificial microvascular network (AMVN). Human RBCs were collected from healthy consenting volunteers, leukoreduced, washed and exposed to graded concentrations (0-0.08%) of glutaraldehyde (a non-specific protein cross-linker) and diamide (a spectrin-specific protein cross-linker) to impair the deformability of RBCs. Samples comprising cells with two different levels of deformability were created by adding non-deformable RBCs (hardened by exposure to 0.08% glutaraldehyde) to the sample of normal healthy RBCs. Ektacytometry indicated a nearly linear decline in RBC deformability with increasing glutaraldehyde concentration. Micropore filtration showed a significant reduction only for concentrations of glutaraldehyde higher than 0.04%. Neither micropore filtration nor ektacytometry measurements could accurately predict the AMVN perfusion. Treatment with diamide reduced RBC deformability as indicated by ektacytometry, but had no significant effect on either micropore filtration or the AMVN perfusion. Both micropore filtration and ektacytometry showed a linear decline in effective RBC deformability with increasing fraction of non-deformable RBCs in the sample. The corresponding decline in the AMVN perfusion plateaued above 50%, reflecting the innate ability of blood flow in the microvasculature to bypass occluded capillaries. Our results suggest that in vitro measurements of RBC deformability performed using either micropore filtration or ektacytometry may not represent the ability of same RBCs to perfuse microvascular networks. Further

  9. Cerebral microvascular blood flow and CO2 reactivity in pulmonary arterial hypertension.

    Science.gov (United States)

    Treptow, Erika; Oliveira, Mayron F; Soares, Aline; Ramos, Roberta P; Medina, Luiz; Lima, Rita; Alencar, Maria Clara; Ferreira, Eloara Vieira; Ota-Arakaki, Jaquelina S; Tufik, Sergio; Nery, Luiz E; Bittencourt, Lia Rita; Neder, J Alberto

    2016-11-01

    Hypocapnia and endothelial dysfunction might impair microvascular cerebral blood flow (CBFmicr) and cerebrovascular reactivity to CO2 (CVRCO2). Pulmonary arterial hypertension (PAH) is characteristically associated with chronic alveolar hyperventilation and microvascular endothelial dysfunction. We therefore determined CBFmicr (pre-frontal blood flow index (BFI) by the indocyanine green-near infrared spectroscopy methodology) during hypocapnia and hypercapnia in 25 PAH patients and 10 gender- and age-matched controls. Cerebral BFI was lower in patients than controls at similar transcutaneous PCO2 (PtcCO2) levels in both testing conditions. In fact, while BFI increased from hypocapnia to hypercapnia in all controls, it failed to increase in 17/25 (68%) patients. Thus, BFI increased to a lesser extent from hypo to hypercapnia ("Δ") in patients, i.e., they showed lower Δ BFI/Δ PtcCO2 ratios than controls. In conclusion, CBFmicr and CVRCO2 are lessened in clinically stable, mildly-impaired patients with PAH. These abnormalities might be associated with relevant clinical outcomes (hyperventilation and dyspnea, cognition, cerebrovascular disease) being potentially amenable to pharmacological treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Functional Response of Tumor Vasculature to PaCO2: Determination of Total and Microvascular Blood Volume by MRI

    Directory of Open Access Journals (Sweden)

    Scott D. Packard

    2003-07-01

    Full Text Available In order to identify differences in functional activity, we compared the reactivity of glioma vasculature and the native cerebral vasculature to both dilate and constrict in response to altered PaCO2. Gliomas were generated by unilateral implantation of U87MGdEGFR human glioma tumor cells into the striatum of adult female athymic rats. Relative changes in total and microvascular cerebral blood volume were determined by steady state contrast agent-enhanced magnetic resonance imaging for transitions from normocarbia to hypercarbia and hypocarbia. Although hypercarbia induced a significant increase in both total and microvascular blood volume in normal brain and glioma, reactivity of glioma vasculature was significantly blunted in comparison to normal striatum; glioma total CBV increased by 0.6±0.1%/mm Hg CO2 whereas normal striatum increased by 1.5±0.2%/mm Hg CO2, (P < .0001, group t-test. Reactivity of microvascular blood volume was also significantly blunted. In contrast, hypocarbia decreased both total and microvascular blood volumes more in glioma than in normal striatum. These results indicate that cerebral blood vessels derived by tumor-directed angiogenesis do retain reactivity to CO2. Furthermore, reduced reactivity of tumor vessels to a single physiological perturbation, such as hypercarbia, should not be construed as a generalized reduction of functional activity of the tumor vascular bed.

  11. Modeling of cerebral oxygen transport based on in vivo microscopic imaging of microvascular network structure, blood flow and oxygenation

    Directory of Open Access Journals (Sweden)

    Louis Gagnon

    2016-08-01

    Full Text Available Oxygen is delivered to brain tissue by a dense network of microvessels, which actively control cerebral blood flow (CBF through vasodilation and contraction in response to changing levels of neural activity. Understanding these network-level processes is immediately relevant for (1 interpretation of functional Magnetic Resonance Imaging (fMRI signals, and (2 investigation of neurological diseases in which a deterioration of neurovascular and neuro-metabolic physiology contributes to motor and cognitive decline. Experimental data on the structure, flow and oxygen levels of microvascular networks are needed, together with theoretical methods to integrate this information and predict physiologically relevant properties that are not directly measurable. Recent progress in optical imaging technologies for high-resolution in vivo measurement of the cerebral microvascular architecture, blood flow, and oxygenation enables construction of detailed computational models of cerebral hemodynamics and oxygen transport based on realistic three-dimensional microvascular networks. In this article, we review state-of-the-art optical microscopy technologies for quantitative in vivo imaging of cerebral microvascular structure, blood flow and oxygenation, and theoretical methods that utilize such data to generate spatially resolved models for blood flow and oxygen transport. These bottom-up models are essential for the understanding of the processes governing brain oxygenation in normal and disease states and for eventual translation of the lessons learned from animal studies to humans.

  12. The Blood-Brain Barrier and Microvascular Water Exchange in Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Valerie C. Anderson

    2011-01-01

    Full Text Available Alzheimer's disease (AD is the most common form of dementia in the elderly. Although traditionally considered a disease of neurofibrillary tangles and amyloid plaques, structural and functional changes in the microvessels may contribute directly to the pathogenesis of the disease. Since vascular dysfunction often precedes cognitive impairment, understanding the role of the blood-brain barrier (BBB in AD may be key to rational treatment of the disease. We propose that water regulation, a critical function of the BBB, is disturbed in AD and results in abnormal permeability and rates of water exchange across the vessel walls. In this paper, we describe some of the pathological events that may disturb microvascular water exchange in AD and examine the potential of a relatively new imaging technique, dynamic contrast-enhanced MRI, to quantify water exchange on a cellular level and thus serve as a probe of BBB integrity in AD.

  13. Nailfold capillaroscopy and blood flow laser-doppler analysis of the microvascular damage in systemic sclerosis: preliminary results

    Directory of Open Access Journals (Sweden)

    C. Pizzorni

    2011-06-01

    Full Text Available Objectives: Systemic sclerosis (SSc is characterized by altered microvascular structure and function. Nailfold videocapillaroscopy (NVC is the tool to evaluate capillary morphological structure and laser-Doppler Blood flowmetry (LDF can be used to estimate cutaneous blood flow of microvessels. The aim of this study was to investigate possible relationships between capillary morphology and blood flow in SSc. Methods: 27 SSc patients and 12 healthy subjects were enrolled. SSc microvascular involvement, as evaluated by NVC, was classified in three different patterns (“Early”, “Active”, “Late”. LDF analysis was performed at the II, III, IV, V hand fingers in both hands and both at cutaneous temperature and at 36°C. Statistical evaluation was carried out by non-parametric procedures. Results: Blood flow was found significantly lower in SSc patients when compared with healthy subjects (p<0.05. The heating of the probe to 36°C induced a significant increase in peripheral blood flow in all subjects compared to baseline (p <0.05, however, the amount of variation was significantly lower in patients with SSc, compared with healthy controls (p <0.05. The SSc patients with NVC “Late” pattern, showed lower values of peripheral blood flow than patients with NVC “Active” or “Early” patterns (p<0.05. Moreover, a negative correlation between the tissue perfusion score and the progression of the SSc microangiopathy was observed, as well as between the tissue perfusion and the duration of the Raynaud’s phenomenon (p <0.03. Conclusions: LDF can be employed to evaluate blood perfusion in the microvascular circulation in SSc patients. The blood flow changes observed with the LDF seem to correlate with the severity of microvascular damage in SSc as detected by NVC.

  14. The Diagnostic Value of Superb Microvascular Imaging (SMI) in Detecting Blood Flow Signals of Breast Lesions

    Science.gov (United States)

    Ma, Yan; Li, Gang; Li, Jing; Ren, Wei-dong

    2015-01-01

    Abstract The correlation between color Doppler flow imaging (CDFI) and Superb Microvascular Imaging (SMI) for detecting blood flow in breast lesions was investigated, as was the diagnostic value of SMI in differentiating benign from malignant breast lesions. These lesions were evaluated using both CDFI and SMI according to Adler's method. Pathologic examination showed 57 malignant lesions and 66 benign lesions. The number of blood vessels in a single mass was detected by 2 techniques (SMI and CDFI), and the difference between the 2 values (SMI-CDFI) was calculated. The optimal threshold for the diagnosis of malignant neoplasms and the diagnostic performances of SMI, CDFI, and SMI-CDFI were calculated. For the total lesions and malignant lesions alone, the difference between SMI and CDFI for detecting blood flow was significant (P < 0.01), but the difference was not significant for benign lesions (P = 0.15). The area under the receiver operating characteristic curve was 0.73 (95% confidence interval [CI]: 0.64–0.82) for CDFI; 0.81 (95% CI: 0.74–0.89) for SMI; and 0.89 (95% CI: 0.82–0.95) for SMI-CDFI. Furthermore, the modality of “SMI-CDFI” showed the best diagnostic performance. SMI provides further microvessel information in breast lesions. The diagnostic modality of “SMI-CDFI” can improve the diagnostic performance of ultrasound in the differentiation between benign and malignant masses. PMID:26356718

  15. Pulsatile microvascular blood flow imaging by short-time Fourier transform analysis of ultrafast laser holographic interferometry

    CERN Document Server

    Puyo, L; Rancillac, A; Simonutti, M; Paques, M; Sahel, J A; Fink, M; Atlan, M

    2015-01-01

    We report on wide-field imaging of pulsatile microvascular blood flow in the exposed cerebral cortex of a mouse by holographic interferometry. We recorded interferograms of laser light backscattered by the tissue, beating against an off-axis reference beam with a 50 kHz framerate camera. Videos of local Doppler contrasts were rendered numerically by Fresnel transformation and short-time Fourier transform analysis. This approach enabled instantaneous imaging of pulsatile blood flow contrasts in superficial blood vessels over 256 x 256 pixels with a spatial resolution of 10 microns and a temporal resolution of 20 ms.

  16. Increased forearm blood flow in longstanding Type 1 diabetic patients without microvascular complications.

    NARCIS (Netherlands)

    Gurp, P.J.M. van; Lenders, J.W.M.; Tack, C.J.J.

    2007-01-01

    AIMS: According to the 'haemodynamic hypothesis', chronic hyperglycaemia induces an increase in tissue perfusion that predisposes to microangiopathy. We hypothesized that patients with longstanding diabetes mellitus (DM), who have not developed microvascular complications, would have normal tissue p

  17. U.S. Should Reinforce Blood Supply: Report

    Science.gov (United States)

    ... news/fullstory_162245.html U.S. Should Reinforce Blood Supply: Report New illnesses and financial pressures are potential ... Nov. 28, 2016 (HealthDay News) -- The U.S. blood supply system faces financial and other challenges that could ...

  18. Dynamic contrast-enhanced MRI assessment of hyperemic fractional microvascular blood plasma volume in peripheral arterial disease: initial findings.

    Directory of Open Access Journals (Sweden)

    Bas Versluis

    Full Text Available OBJECTIVES: The aim of the current study was to describe a method that assesses the hyperemic microvascular blood plasma volume of the calf musculature. The reversibly albumin binding contrast agent gadofosveset was used in dynamic contrast-enhanced magnetic resonance imaging (DCE MRI to assess the microvascular status in patients with peripheral arterial disease (PAD and healthy controls. In addition, the reproducibility of this method in healthy controls was determined. MATERIALS AND METHODS: Ten PAD patients with intermittent claudication and 10 healthy control subjects were included. Patients underwent contrast-enhanced MR angiography of the peripheral arteries, followed by one DCE MRI examination of the musculature of the calf. Healthy control subjects were examined twice on different days to determine normative values and the interreader and interscan reproducibility of the technique. The MRI protocol comprised dynamic imaging of contrast agent wash-in under reactive hyperemia conditions of the calf musculature. Using pharmacokinetic modeling the hyperemic fractional microvascular blood plasma volume (V(p, unit: % of the anterior tibial, gastrocnemius and soleus muscles was calculated. RESULTS: V(p was significantly lower for all muscle groups in PAD patients (4.3±1.6%, 5.0±3.3% and 6.1±3.6% for anterior tibial, gastrocnemius and soleus muscles, respectively compared to healthy control subjects (9.1±2.0%, 8.9±1.9% and 9.3±2.1%. Differences in V(p between muscle groups were not significant. The coefficient of variation of V(p varied from 10-14% and 11-16% at interscan and interreader level, respectively. CONCLUSIONS: Using DCE MRI after contrast-enhanced MR angiography with gadofosveset enables reproducible assessment of hyperemic fractional microvascular blood plasma volume of the calf musculature. V(p was lower in PAD patients than in healthy controls, which reflects a promising functional (hemodynamic biomarker for the

  19. Systemic and Microvascular Effects of Resuscitation with Blood Products After Severe Hemorrhage in Rats

    Science.gov (United States)

    2014-01-01

    structural organization and stability of individual gly- cocalyx components, such as glycoproteins, proteoglycans with glycosaminoglycans, and adsorbed...adsorbed proteins and proteoglycans and therefore increase microvascular flow,32 which supports our findings that resuscitation with LR may cause...from cremaster preparations. B, Levels of plasma heparan sulfate proteoglycan relative to baseline after hemorrhage and resuscitation treatment. LR

  20. [Blood transfusion and supply chain management safety].

    Science.gov (United States)

    Quaranta, Jean-François; Caldani, Cyril; Cabaud, Jean-Jacques; Chavarin, Patricia; Rochette-Eribon, Sandrine

    2015-02-01

    The level of safety attained in blood transfusion now makes this a discipline better managed care activities. This was achieved both by scientific advances and policy decisions regulating and supervising the activity, as well as by the quality system, which we recall that affects the entire organizational structure, responsibilities, procedures, processes and resources in place to achieve quality management. So, an effective quality system provides a framework within which activities are established, performed in a quality-focused way and continuously monitored to improve outcomes. This system quality has to irrigate all the actors of the transfusion, just as much the establishments of blood transfusion than the health establishments.

  1. Which side of the balance determines the frequency of vaso-occlusive crises in children with sickle cell anemia: Blood viscosity or microvascular dysfunction?

    Science.gov (United States)

    Charlot, Keyne; Romana, Marc; Moeckesch, Berenike; Jumet, Stéphane; Waltz, Xavier; Divialle-Doumdo, Lydia; Hardy-Dessources, Marie-Dominique; Petras, Marie; Tressières, Benoît; Tarer, Vanessa; Hue, Olivier; Etienne-Julan, Maryse; Antoine-Jonville, Sophie; Connes, Philippe

    2016-01-01

    Vascular resistance and tissue perfusion may be both affected by impaired vascular function and increased blood viscosity. Little is known about the effects of vascular function on the occurrence of painful vaso-occlusive crises (VOC) in children with sickle cell anemia (SCA). The aim of the present study was to determine which side of the balance (blood viscosity or vascular function) is the most deleterious in SCA and increases the risk for frequent hospitalized VOC. Microvascular function, microcirculatory oxygenation and blood viscosity were determined in a group of 22 SCA children/adolescents at steady state and a group of 13 healthy children/adolescents. Univariate analyses demonstrated blunted microvascular reactivity during local thermal heating test and decreased microcirculatory oxygenation in SCA children compared to controls. Multivariate analysis revealed that increased blood viscosity and decreased microcirculatory oxygenation were independent risk factors of frequent VOC in SCA. In contrast, the level of microvascular dysfunction does not predict VOC rate. In conclusion, increased blood viscosity is usually well supported in healthy individuals where vascular function is not impaired. However, in the context of SCA, microvascular function is impaired and any increase of blood viscosity or decrease in microcirculatory oxygenation would increase the risks for frequent VOC.

  2. Challenges in the management of the blood supply.

    Science.gov (United States)

    Williamson, Lorna M; Devine, Dana V

    2013-05-25

    Although blood suppliers are seeing short-term reductions in blood demand as a result of initiatives in patient blood management, modelling suggests that during the next 5-10 years, blood availability in developed countries will need to increase again to meet the demands of ageing populations. Increasing of the blood supply raises many challenges; new approaches to recruitment and retainment of future generations of blood donors will be needed, and care will be necessary to avoid taking too much blood from these donors. Integrated approaches in blood stock management between transfusion services and hospitals will be important to minimise wastage--eg, by use of supply chain solutions from industry. Cross-disciplinary systems for patient blood management need to be developed to lessen the need for transfusion--eg, by early identification and reversal of anaemia with haematinics or by reversal of the underlying cause. Personalised medicine could be applied to match donors to patients, not only with extended blood typing, but also by using genetically determined storage characteristics of blood components. Growing of red cells or platelets in large quantities from stem cells is a possibility in the future, but challenges of cost, scaling up, and reproducibility remain to be solved.

  3. Galectin-1 suppresses methamphetamine induced neuroinflammation in human brain microvascular endothelial cells: Neuroprotective role in maintaining blood brain barrier integrity.

    Science.gov (United States)

    Parikh, Neil U; Aalinkeel, R; Reynolds, J L; Nair, B B; Sykes, D E; Mammen, M J; Schwartz, S A; Mahajan, S D

    2015-10-22

    Methamphetamine (Meth) abuse can lead to the breakdown of the blood-brain barrier (BBB) integrity leading to compromised CNS function. The role of Galectins in the angiogenesis process in tumor-associated endothelial cells (EC) is well established; however no data are available on the expression of Galectins in normal human brain microvascular endothelial cells and their potential role in maintaining BBB integrity. We evaluated the basal gene/protein expression levels of Galectin-1, -3 and -9 in normal primary human brain microvascular endothelial cells (BMVEC) that constitute the BBB and examined whether Meth altered Galectin expression in these cells, and if Galectin-1 treatment impacted the integrity of an in-vitro BBB. Our results showed that BMVEC expressed significantly higher levels of Galectin-1 as compared to Galectin-3 and -9. Meth treatment increased Galectin-1 expression in BMVEC. Meth induced decrease in TJ proteins ZO-1, Claudin-3 and adhesion molecule ICAM-1 was reversed by Galectin-1. Our data suggests that Galectin-1 is involved in BBB remodeling and can increase levels of TJ proteins ZO-1 and Claudin-3 and adhesion molecule ICAM-1 which helps maintain BBB tightness thus playing a neuroprotective role. Galectin-1 is thus an important regulator of immune balance from neurodegeneration to neuroprotection, which makes it an important therapeutic agent/target in the treatment of drug addiction and other neurological conditions.

  4. The Key Role of the Blood Supply to Bone

    Institute of Scientific and Technical Information of China (English)

    Massimo Marenzana; Timothy R. Arnett

    2013-01-01

    The importance of the vascular supply for bone is well-known to orthopaedists but is still rather overlooked within the wider field of skeletal research. Blood supplies oxygen, nutrients and regulatory factors to tissues, as well as removing metabolic waste products such as carbon dioxide and acid. Bone receives up to about 10%of cardiac output, and this blood supply permits a much higher degree of cellularity, remodelling and repair than is possible in cartilage, which is avascular. The blood supply to bone is delivered to the endosteal cavity by nutrient arteries, then flows through marrow sinusoids before exiting via numerous small vessels that ramify through the cortex. The marrow cavity affords a range of vascular niches that are thought to regulate the growth and differentiation of hematopoietic and stromal cells, in part via gradients of oxygen tension. The quality of vascular supply to bone tends to decline with age and may be compromised in common pathological settings, including diabetes, anaemias, chronic airway diseases and immobility, as well as by tumours. Reductions in vascular supply are associated with bone loss. This may be due in part to the direct effects of hypoxia, which blocks osteoblast function and bone formation but causes reciprocal increases in osteoclastogenesis and bone resorption. Common regulatory factors such as parathyroid hormone or nitrates, both of which are potent vasodilators, might exert their osteogenic effects on bone via the vasculature. These observations suggest that the bone vasculature will be a fruitful area for future research.

  5. A new method to study changes in microvascular blood volume in muscle and adipose tissue: Real time imaging in humans and rat

    DEFF Research Database (Denmark)

    Sjøberg, Kim Anker; Rattigan, Stephen; Hiscock, Natalie J

    2011-01-01

    We employed and evaluated a new application of contrast enhanced ultrasound for real time imaging of changes in microvascular blood volume (MVB) in tissues in females, males and rat. Continuous real time imaging was performed using contrast enhanced ultrasound to quantify infused gas filled micro...

  6. Blood product collection and supply: a matter of money?

    Science.gov (United States)

    de Kort, W; Wagenmans, E; van Dongen, A; Slotboom, Y; Hofstede, G; Veldhuizen, I

    2010-04-01

    Previous studies have shown that countries with a low or medium Human Development Index (HDI) transfuse far fewer blood products than countries with a high HDI. HDI comprises both economical and non-economical elements. We considered the hypothesis that non-economical, cultural differences may be additional factors in understanding blood donation and blood supply differences. We quantified the explained variance, r(2), in: the number of donors, the number of whole blood collections and the number of red blood cell units supplied to hospitals for 25 European countries. Candidate predictors were Hofstede's cultural dimensions, the demographic factor Old Age Dependency Ratio and the three components of HDI: Gross National Income, Life Expectancy and the Educational Development Index. The cultural dimension Power Distance was the best sole predictor of whole blood collection (r(2) = 56.8%) and the number of donors (r(2) = 25.1%). The Educational Development Index best predicted the number of red blood cell units (r(2) = 45.0%). Multivariable models including the cultural dimension Power Distance and the Educational Development Index gave the best results in predicting the number of whole blood collections and red blood cell units supplied and, to a lesser extent, the number of donors, with adjusted r(2) values of 63.6%, 51.9% and 28.6%, respectively. In contrast, Gross National Income made no significant predictive contribution to any of the multivariable models. Neither did the other cultural dimensions, Life Expectancy or Old Age Dependency Ratio. The effects of education level and cultural aspects should be taken into account as influencers on donation behaviour. The concept of power distance, in particular, presents a challenge to blood donor managers in cross-cultural and multi-cultural donor management contexts.

  7. Tick-borne encephalitis virus infects human brain microvascular endothelial cells without compromising blood-brain barrier integrity.

    Science.gov (United States)

    Palus, Martin; Vancova, Marie; Sirmarova, Jana; Elsterova, Jana; Perner, Jan; Ruzek, Daniel

    2017-07-01

    Alteration of the blood-brain barrier (BBB) is a hallmark of tick-borne encephalitis (TBE), a life-threating human viral neuroinfection. However, the mechanism of BBB breakdown during TBE, as well as TBE virus (TBEV) entry into the brain is unclear. Here, primary human microvascular endothelial cells (HBMECs) were infected with TBEV to study interactions with the BBB. Although the number of infected cells was relatively low in culture (10(6)pfu/ml). Infection did not induce any significant changes in the expression of key tight junction proteins or upregulate the expression of cell adhesion molecules, and did not alter the highly organized intercellular junctions between HBMECs. In an in vitro BBB model, the virus crossed the BBB via a transcellular pathway without compromising the integrity of the cell monolayer. The results indicate that HBMECs may support TBEV entry into the brain without altering BBB integrity. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Real-time contrast-enhanced ultrasound determination of microvascular blood volume in abdominal subcutaneous adipose tissue in man. Evidence for adipose tissue capillary recruitment

    DEFF Research Database (Denmark)

    Tobin, L; Simonsen, L; Bülow, J

    2010-01-01

    The adipose tissue metabolism is dependent on its blood perfusion. During lipid mobilization e.g. during exercise and during lipid deposition e.g. postprandial, adipose tissue blood flow is increased. This increase in blood flow may involve capillary recruitment in the tissue. We investigated...... the basic and postprandial microvascular volume in adipose tissue using real-time contrast-enhanced ultrasound (CEU) imaging in healthy normal weight subjects. In nine subjects, CEU was performed in abdominal subcutaneous adipose tissue and in the underlying skeletal muscle after a bolus injection...... of ultrasound contrast agent to establish the reproducibility of the technique. In nine subjects, the effect of an oral glucose load on blood flow and microvascular volume was measured in abdominal subcutaneous adipose tissue and forearm skeletal muscle. ¹³³Xe washout and venous occlusion strain...

  9. Numerical Modeling of Interstitial Fluid Flow Coupled with Blood Flow through a Remodeled Solid Tumor Microvascular Network.

    Directory of Open Access Journals (Sweden)

    M Soltani

    Full Text Available Modeling of interstitial fluid flow involves processes such as fluid diffusion, convective transport in extracellular matrix, and extravasation from blood vessels. To date, majority of microvascular flow modeling has been done at different levels and scales mostly on simple tumor shapes with their capillaries. However, with our proposed numerical model, more complex and realistic tumor shapes and capillary networks can be studied. Both blood flow through a capillary network, which is induced by a solid tumor, and fluid flow in tumor's surrounding tissue are formulated. First, governing equations of angiogenesis are implemented to specify the different domains for the network and interstitium. Then, governing equations for flow modeling are introduced for different domains. The conservation laws for mass and momentum (including continuity equation, Darcy's law for tissue, and simplified Navier-Stokes equation for blood flow through capillaries are used for simulating interstitial and intravascular flows and Starling's law is used for closing this system of equations and coupling the intravascular and extravascular flows. This is the first study of flow modeling in solid tumors to naturalistically couple intravascular and extravascular flow through a network. This network is generated by sprouting angiogenesis and consisting of one parent vessel connected to the network while taking into account the non-continuous behavior of blood, adaptability of capillary diameter to hemodynamics and metabolic stimuli, non-Newtonian blood flow, and phase separation of blood flow in capillary bifurcation. The incorporation of the outlined components beyond the previous models provides a more realistic prediction of interstitial fluid flow pattern in solid tumors and surrounding tissues. Results predict higher interstitial pressure, almost two times, for realistic model compared to the simplified model.

  10. The effect of eccentric exercise with blood flow restriction on neuromuscular activation, microvascular oxygenation, and the repeated bout effect.

    Science.gov (United States)

    Lauver, Jakob D; Cayot, Trent E; Rotarius, Timothy; Scheuermann, Barry W

    2017-05-01

    To examine the effect of low-intensity eccentric contractions with and without blood flow restriction (BFR) on microvascular oxygenation, neuromuscular activation, and the repeated bout effect (RBE). Participants were randomly assigned to either low-intensity (LI), low-intensity with BFR (LI-BFR), or a control (CON) group. Participants in LI and LI-BFR performed a preconditioning bout of low-intensity eccentric exercise prior to about of maximal eccentric exercise. Participants reported 24, 48, 72, and 96 h later to assess muscle damage and function. Surface electromyography (sEMG) and near-infrared spectroscopy (NIRS) were used to measure neuromuscular activation and microvascular deoxygenation (deoxy-[Hb + Mb]) and [total hemoglobin] ([THC]) during the preconditioning bout, respectively. During set-2, LI-BFR resulted in greater activation of the VM-RMS (47.7 ± 11.5% MVIC) compared to LI (67.0 ± 20.0% MVIC), as well as during set-3 (p exercise (LI 74.2 ± 14.1%, LI-BFR 75 ± 5.1%, CON 53 ± 18.6%). At 24, 48, 72, and 96 h post maximal eccentric exercise, LI and LI-BFR force deficit was not different from baseline. This study suggests that the neuromuscular and deoxygenation (i.e., metabolic stress) responses were considerably different between LI and LI-BFR groups; however, these differences did not lead to improvements in the RBE inferred by performing LI and LI-BFR.

  11. Two problems in multiphase biological flows: Blood flow and particulate transport in microvascular network, and pseudopod-driven motility of amoeboid cells

    Science.gov (United States)

    Bagchi, Prosenjit

    2016-11-01

    In this talk, two problems in multiphase biological flows will be discussed. The first is the direct numerical simulation of whole blood and drug particulates in microvascular networks. Blood in microcirculation behaves as a dense suspension of heterogeneous cells. The erythrocytes are extremely deformable, while inactivated platelets and leukocytes are nearly rigid. A significant progress has been made in recent years in modeling blood as a dense cellular suspension. However, many of these studies considered the blood flow in simple geometry, e.g., straight tubes of uniform cross-section. In contrast, the architecture of a microvascular network is very complex with bifurcating, merging and winding vessels, posing a further challenge to numerical modeling. We have developed an immersed-boundary-based method that can consider blood cell flow in physiologically realistic and complex microvascular network. In addition to addressing many physiological issues related to network hemodynamics, this tool can be used to optimize the transport properties of drug particulates for effective organ-specific delivery. Our second problem is pseudopod-driven motility as often observed in metastatic cancer cells and other amoeboid cells. We have developed a multiscale hydrodynamic model to simulate such motility. We study the effect of cell stiffness on motility as the former has been considered as a biomarker for metastatic potential. Funded by the National Science Foundation.

  12. [Blood supply during disasters: the experience of Chile in 2010].

    Science.gov (United States)

    Vásquez, Marcela; Maldonado, Mónica; Tagle, Federico; León, Sergio; Soto, Alejandra; Mena, Aaron; Toro, Carla

    2011-05-01

    A review of the management of blood supply and its administration during disasters was conducted based on the experience of several events that occurred primarily from 2000-2010, particularly the earthquake that measured 8.8 on the Richter scale that struck central and southern Chile on 27 February 2010. The objective was to provide information that could be useful in improving response plans and strategies during potential future disasters. The descriptive information on response procedures was obtained from interviews, internal reports, and the computer database from the Maule regional blood production center. The results lead to the conclusion that to respond efficiently and effectively to the need for blood in the immediate wake of a disaster it is essential to have both a centralized management system that facilitates the supply and administration of blood and volunteers with competence in health that are willing to swiftly arrive during these events. A change in the profile of blood donors during such emergencies was also observed. In Chile, for example, during the two weeks after the earthquake, the ratio of male/female donors was reversed. There was 61.1% participation by women, whereas in the week before the event women accounted for only 37%.

  13. Microvascular Architecture of Hepatic Metastases in a Mouse Model

    Directory of Open Access Journals (Sweden)

    Darshini Kuruppu

    1997-01-01

    Full Text Available Development of effective treatment for hepatic metastases can be initiated by a better understanding of tumour vasculature and blood supply. This study was designed to characterise the microvascular architecture of hepatic metastases and observe the source of contributory blood supply from the host. Metastases were induced in mice by an intrasplenic injection of colon carcinoma cells (106 cells/ml. Vascularization of tumours was studied over a three week period by scanning electron microscopy of microvascular corrosion casts. Metastatic liver involvement was observed initially within a week post induction, as areas approximately 100 μm in diameter not perfused by the casting resin. On histology these spaces corresponded to tumour cell aggregates. The following weeks highlighted the angiogenesis phase of these tumours as they received a vascular supply from adjacent hepatic sinusoids. Direct sinusoidal supply of metastases was maintained throughout tumour growth. At the tumour periphery most sinusoids were compressed to form a sheath demarcating the tumour from the hepatic vasculature. No direct supply from the hepatic artery or the portal vein was observed. Dilated vessels termed vascular lakes dominated the complex microvascular architecture of the tumours, most tapering as they traversed towards the periphery. Four vascular branching patterns could be identified as true loops, bifurcations and trifurcations, spirals and capillary networks. The most significant observation in this study was the direct sinusoidal supply of metastases, together with the vascular lakes and the peripheral sinusoidal sheaths of the tumour microculature.

  14. A robust optimization model for blood supply chain in emergency situations

    OpenAIRE

    Meysam Fereiduni; Kamran Shahanaghi

    2016-01-01

    In this paper, a multi-period model for blood supply chain in emergency situation is presented to optimize decisions related to locate blood facilities and distribute blood products after natural disasters. In disastrous situations, uncertainty is an inseparable part of humanitarian logistics and blood supply chain as well. This paper proposes a robust network to capture the uncertain nature of blood supply chain during and after disasters. This study considers donor points, blood facilities,...

  15. Real-time contrast-enhanced ultrasound determination of microvascular blood volume in abdominal subcutaneous adipose tissue in man. Evidence for adipose tissue capillary recruitment

    DEFF Research Database (Denmark)

    Tobin, L; Simonsen, L; Bülow, J

    2010-01-01

    the basic and postprandial microvascular volume in adipose tissue using real-time contrast-enhanced ultrasound (CEU) imaging in healthy normal weight subjects. In nine subjects, CEU was performed in abdominal subcutaneous adipose tissue and in the underlying skeletal muscle after a bolus injection...... of ultrasound contrast agent to establish the reproducibility of the technique. In nine subjects, the effect of an oral glucose load on blood flow and microvascular volume was measured in abdominal subcutaneous adipose tissue and forearm skeletal muscle. ¹³³Xe washout and venous occlusion strain......-gauge plethysmography was used to measure the adipose tissue and forearm blood flow, respectively. Ultrasound signal intensity of the first plateau phases was 27 ± dB in the abdominal subcutaneous adipose tissue and 18 ± 2 dB (P muscle. The reproducibility of the measurements was good...

  16. Effect of antihypertensive treatment on microvascular structure, central blood pressure and oxidative stress in patients with mild essential hypertension.

    Science.gov (United States)

    De Ciuceis, Carolina; Salvetti, Massimo; Rossini, Claudia; Muiesan, Maria Lorenza; Paini, Anna; Duse, Sarah; La Boria, Elisa; Semeraro, Francesco; Cancarini, Anna; Rosei, Claudia Agabiti; Sarkar, Annamaria; Ruggeri, Giuseppina; Caimi, Luigi; Ricotta, Doris; Rizzoni, Damiano; Rosei, Enrico Agabiti

    2014-03-01

    monotherapy and in combination with enalapril, was able to improve microvascular structure and to decrease central blood pressure, being thus a useful approach for both reducing blood pressure and improving vascular alterations in hypertension.

  17. U.S. Blood Supply Safe from Zika Virus, Officials Say

    Science.gov (United States)

    ... fullstory_164519.html U.S. Blood Supply Safe From Zika Virus, Officials Say They detail steps being taken ... to protect America's blood supply from possible new Zika virus outbreaks during the upcoming mosquito season. A ...

  18. Human Brain Microvascular Endothelial Cells Derived from the BC1 iPS Cell Line Exhibit a Blood-Brain Barrier Phenotype

    OpenAIRE

    Katt, Moriah E.; Xu, Zinnia S.; Gerecht, Sharon; Searson, Peter C.

    2016-01-01

    The endothelial cells that form capillaries in the brain are highly specialized, with tight junctions that minimize paracellular transport and an array of broad-spectrum efflux pumps that make drug delivery to the brain extremely challenging. One of the major limitations in blood-brain barrier research and the development of drugs to treat central nervous system diseases is the lack of appropriate cell lines. Recent reports indicate that the derivation of human brain microvascular endothelial...

  19. Observation of Microvascular Perfusion in the Hegu (LI4 Acupoint Area after Deqi Acupuncture at Quchi (LI11 Acupoint Using Speckle Laser Blood Flow Scanning Technology

    Directory of Open Access Journals (Sweden)

    Tao Huang

    2012-01-01

    Full Text Available The aim of this study was to investigate the traditional meridian theory using speckle laser blood flow scanning technology to observe microcirculation of the Hegu acupoint area after acupuncture stimulation on distant points. An observational study was conducted to observe the microvascular perfusion of Hegu (LI4 and control points after acupuncturing Quchi (LI11. Thirty healthy volunteers (mean age 31.6±8.7 years received deqi acupuncture on Quchi (LI11, right side, and simultaneously changes in microvascular perfusion of Sanjian (LI3, Hegu (LI4, Yangxi (LI5, and two control points were observed before, during, and after needling using a MOOR speckle laser. The results showed that the changes in microvascular perfusion of the observed points are not regular. After correction, the experiment showed that the blood perfusion on 3 meridian acupoints was increased while the perfusion on 2 control points was decreased following acupuncture stimulation, the changes at Hegu (LI4 being the statistically most significant ones. Deqi acupuncture can help in regulating the body's blood flow, with a certain degree of meridian specificity.

  20. Observation of Microvascular Perfusion in the Hegu (LI4) Acupoint Area after Deqi Acupuncture at Quchi (LI11) Acupoint Using Speckle Laser Blood Flow Scanning Technology.

    Science.gov (United States)

    Huang, Tao; Yang, Li-Jian; Zhang, Wei-Bo; Jia, Shu-Yong; Tian, Yu-Ying; Wang, Guan-Jun; Mu, Xiang; Wang, Lu; Litscher, Gerhard

    2012-01-01

    The aim of this study was to investigate the traditional meridian theory using speckle laser blood flow scanning technology to observe microcirculation of the Hegu acupoint area after acupuncture stimulation on distant points. An observational study was conducted to observe the microvascular perfusion of Hegu (LI4) and control points after acupuncturing Quchi (LI11). Thirty healthy volunteers (mean age 31.6 ± 8.7 years) received deqi acupuncture on Quchi (LI11, right side), and simultaneously changes in microvascular perfusion of Sanjian (LI3), Hegu (LI4), Yangxi (LI5), and two control points were observed before, during, and after needling using a MOOR speckle laser. The results showed that the changes in microvascular perfusion of the observed points are not regular. After correction, the experiment showed that the blood perfusion on 3 meridian acupoints was increased while the perfusion on 2 control points was decreased following acupuncture stimulation, the changes at Hegu (LI4) being the statistically most significant ones. Deqi acupuncture can help in regulating the body's blood flow, with a certain degree of meridian specificity.

  1. Gross and microscopical blood supply of the trachea.

    Science.gov (United States)

    Salassa, J R; Pearson, B W; Payne, W S

    1977-08-01

    Twenty-one human tracheal specimens were perfused and dissected, 10 with conventional techniques and 11 with clearing and microdissection techniques. The lateral pedicles of the trachea and esophagus induct vessels from the inferior thyroid, subclavian, supreme intercostal, internal thoracic, innominate, and superior and middle bronchial arteries. These vessels are interconnected along the lateral surface of the trachea by an important longitudinal vascular anstomosis. From the 2 lateral longitudinal anastomoses the lateral and anterior tracheal walls receive their blood supply through transverse segmental vessels that run in the soft tissues between the cartilages. These transverse vessels interconnect the longitudinal anastomoses across the midline and feed the submucosal capillary network that arborizes richly beneath the endotracheal mucosa. The tracheal cartilages receive nourishment from the capillary bed applied to their internal surface. The esophageal arteries and their subdivisions that supply the posterior membranous wall of the trachea contribute almost nothing to the circulation of the cartilaginous walls.

  2. Zika Virus and the Blood Supply: What Do We Know?

    Science.gov (United States)

    Jimenez, Alexandra; Shaz, Beth H; Bloch, Evan M

    2017-01-01

    Zika virus (ZIKV), a mosquito-borne Flavivirus and emerging infectious disease, is the focus of an international public health emergency after its rapid spread through the Americas and the Caribbean. Although most ZIKV infections are subclinical or characterized by mild febrile illness, ZIKV has been implicated in severe complications, most notably microcephaly in babies born to incident infected mothers during pregnancy. As yet, the extent to which ZIKV is transfusion transmissible remains undefined. Nonetheless, a high prevalence of asymptomatic infection during outbreaks, the demonstration of ZIKV in blood donors, and 4 possible cases of transfusion-transmitted ZIKV in Brazil have raised concern for risk to the blood supply. Consequently, a proactive response is underway by blood collection agencies, regulatory bodies, national funding agencies, and industry alike. Mitigation strategies differ between endemic and nonendemic areas. In the continental United States, the American Association of Blood Banks and Food and Drug Administration guidelines recommend travel-based deferral for those returning from affected areas, and nucleic acid testing is being initiated under an investigational new drug application in Puerto Rico and selected areas of the United States. Options are less clear for countries where autochthonous vector-borne transmission is active. The burden of Zika falls in low-resource countries where high cost and technical barriers associated with testing and pathogen reduction pose barriers to implementation. Additional strategies include maintaining selective inventory for high-risk recipients (eg, pregnant women). We review the available data as of July 2016 on ZIKV in relation to the blood supply including risk, mitigation strategies, and barriers to implementation in addition to the research that is needed to address current uncertainty.

  3. Increased muscle blood supply and transendothelial nutrient and insulin transport induced by food intake and exercise: effect of obesity and ageing.

    Science.gov (United States)

    Wagenmakers, Anton J M; Strauss, Juliette A; Shepherd, Sam O; Keske, Michelle A; Cocks, Matthew

    2016-04-15

    This review concludes that a sedentary lifestyle, obesity and ageing impair the vasodilator response of the muscle microvasculature to insulin, exercise and VEGF-A and reduce microvascular density. Both impairments contribute to the development of insulin resistance, obesity and chronic age-related diseases. A physically active lifestyle keeps both the vasodilator response and microvascular density high. Intravital microscopy has shown that microvascular units (MVUs) are the smallest functional elements to adjust blood flow in response to physiological signals and metabolic demands on muscle fibres. The luminal diameter of a common terminal arteriole (TA) controls blood flow through up to 20 capillaries belonging to a single MVU. Increases in plasma insulin and exercise/muscle contraction lead to recruitment of additional MVUs. Insulin also increases arteriolar vasomotion. Both mechanisms increase the endothelial surface area and therefore transendothelial transport of glucose, fatty acids (FAs) and insulin by specific transporters, present in high concentrations in the capillary endothelium. Future studies should quantify transporter concentration differences between healthy and at risk populations as they may limit nutrient supply and oxidation in muscle and impair glucose and lipid homeostasis. An important recent discovery is that VEGF-B produced by skeletal muscle controls the expression of FA transporter proteins in the capillary endothelium and thus links endothelial FA uptake to the oxidative capacity of skeletal muscle, potentially preventing lipotoxic FA accumulation, the dominant cause of insulin resistance in muscle fibres.

  4. Temporal distribution of blood donations in three Brazilian blood centers and its repercussion on the blood supply

    Science.gov (United States)

    Oliveira, Claudia Di Lorenzo; de Almeida-Neto, Cesar; Liu, Emily Jing; Sabino, Ester Cerdeira; Leão, Silvana Carneiro; Loureiro, Paula; Wright, David; Custer, Brian; Gonçalez, Thelma Therezinha; Capuani, Ligia; Busch, Michael; Proietti, Anna Bárbara de Freitas Carneiro

    2013-01-01

    Background Seasonal distribution of blood donation hinders efforts to provide a safe and adequate blood supply leading to chronic and persistent shortages. This study examined whether holidays, geographical area and donation type (community versus replacement) has any impact on the fluctuation of donations. Methods The numbers of blood donations from 2007 through 2010 in three Brazilian Retrovirus Epidemiological Donor Study II (REDS-II) participating centers were analyzed according to the week of donation. The weeks were classified as holiday or non-holiday. To compare donations performed during holiday versus non-holiday weeks, tabulations and descriptive statistics for weekly donations by blood center were examined and time series analysis was conducted. Results The average weekly number of donations varied according to the blood center and type of week. The average number of donations decreased significantly during Carnival and Christmas and increased during the Brazilian National Donor Week. The fluctuation was more pronounced in Recife and Belo Horizonte when compared to São Paulo and higher among community donors. Conclusion National bank holidays affect the blood supply by reducing available blood donations. Blood banks should take into account these oscillations in order to plan local campaigns, aiming at maintaining the blood supply at acceptable levels. PMID:24106441

  5. Operational effectiveness and quality assurance mechanisms with stochastic demand of blood supply: blood bank case study.

    Science.gov (United States)

    Smith, Alan D

    2011-01-01

    A general overview of various blood products operational effectiveness and related strategies that can be utilised by service providers (in particular, healthcare providers) is presented in the present study. In terms of the massive volumes of blood products, the North American blood centres collect more than eight million units of whole blood, which represents appropriately 50% of the US and Quebec, Canada?s volunteer donor blood supply. A case study of the quality inspection and inventory control concerns of the Central Blood Bank, located in the metropolitan area of Pittsburgh, PA, is presented. Initially, brief introduction to its general operating environment is followed by sections describing its general situation, quality-service initiatives, and followed by a fairly detailed discussion of the practical applications of lessons learned from the case study.

  6. A Lattice Boltzmann Method for Simulating the Separation of Red Blood Cells at Microvascular Bifurcations

    Institute of Scientific and Technical Information of China (English)

    SHEN Zai-Yi; HE Ying

    2012-01-01

    A computational simulation for the separation of red blood cells (RBCs) is presented.The deformability of RBCs is expressed by the spring network model,which is based on the minimum energy principle.In the computation of the fluid flow,the lattice Boltzmann method is used to solve the Navier-Stokes equations.Coupling of the fluid-membrane interaction is carried out by using the immersed boundary method.To verify our method,the motions of RBCs in shear flow are simulated.Typical motions of RBCs observed in the experiments are reproduced,including tank-treading,swinging and tumbling.The motions of 8 RBCs at the bifurcation are simulated when the two daughter vessels have different ratios.The results indicate that when the ratio of the daughter vessel diameter becomes smaller,the distribution of RBCs in the two vessels becomes more non-uniform.%A computational simulation for the separation of red blood cells (RBCs) is presented. The deformability of RBCs is expressed by the spring network model, which is based on the minimum energy principle. In the computation of the fluid Bow, the lattice Boltzmann method is used to solve the Navier-Stokes equations. Coupling of the fluid-membrane interaction is carried out by using the immersed boundary method. To verify our method, the motions of RBCs in shear How are simulated. Typical motions of RBCs observed in the experiments are reproduced, including tank-treading, swinging and tumbling. The motions of 8 RBCs at the bifurcation are simulated when the two daughter vessels have different ratios. The results indicate that when the ratio of te daughter vessel diameter becomes smaller, the distribution of RBCs in the two vessels becomes more non-uniform.

  7. Proximate Mediators of Microvascular Dysfunction at the Blood-Brain Barrier: Neuroinflammatory Pathways to Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Barry W. Festoff

    2017-01-01

    Full Text Available Current projections are that by 2050 the numbers of people aged 65 and older with Alzheimer’s disease (AD in the US may increase threefold while dementia is projected to double every 20 years reaching ~115 million by 2050. AD is clinically characterized by progressive dementia and neuropathologically by neuronal and synapse loss, accumulation of amyloid plaques, and neurofibrillary tangles (NFTs in specific brain regions. The preclinical or presymptomatic stage of AD-related brain changes may begin over 20 years before symptoms occur, making development of noninvasive biomarkers essential. Distinct from neuroimaging and cerebrospinal fluid biomarkers, plasma or serum biomarkers can be analyzed to assess (i the presence/absence of AD, (ii the risk of developing AD, (iii the progression of AD, or (iv AD response to treatment. No unifying theory fully explains the neurodegenerative brain lesions but neuroinflammation (a lethal stressor for healthy neurons is universally present. Current consensus is that the earlier the diagnosis, the better the chance to develop treatments that influence disease progression. In this article we provide a detailed review and analysis of the role of the blood-brain barrier (BBB and damage-associated molecular patterns (DAMPs as well as coagulation molecules in the onset and progression of these neurodegenerative disorders.

  8. Decreased microvascular cerebral blood flow assessed by diffuse correlation spectroscopy after repetitive concussions in mice.

    Science.gov (United States)

    Buckley, Erin M; Miller, Benjamin F; Golinski, Julianne M; Sadeghian, Homa; McAllister, Lauren M; Vangel, Mark; Ayata, Cenk; Meehan, William P; Franceschini, Maria Angela; Whalen, Michael J

    2015-12-01

    Repetitive concussions are associated with long-term cognitive dysfunction that can be attenuated by increasing the time intervals between concussions; however, biomarkers of the safest rest interval between injuries remain undefined. We hypothesize that deranged cerebral blood flow (CBF) is a candidate biomarker for vulnerability to repetitive concussions. Using a mouse model of human concussion, we examined the effect of single and repetitive concussions on cognition and on an index of CBF (CBFi) measured with diffuse correlation spectroscopy. After a single mild concussion, CBFi was reduced by 35±4% at 4 hours (Pconcussions spaced 1 day apart, CBFi was also reduced from preinjury levels 4 hours after each concussion but had returned to preinjury levels by 72 hours after the final concussion. Interestingly, in this repetitive concussion model, lower CBFi values measured both preinjury and 4 hours after the third concussion were associated with worse performance on the Morris water maze assessed 72 hours after the final concussion. We conclude that low CBFi measured either before or early on in the evolution of injury caused by repetitive concussions could be a useful predictor of cognitive outcome.

  9. GROSS ANATOMY AND BLOOD SUPPLY OF SMALL INTESTINE IN FOETUSES

    Directory of Open Access Journals (Sweden)

    Anwer Unisa

    2015-06-01

    Full Text Available AIM OF STUDY: To develop charts of length and width of small intestine, origin, length and branching pattern of celiac trunk and Superior mesenteric artery. This will help us to know any congenital anomaly in the small intestine, and abnormal origin, length, variation i n the branching pattern. MATERIALS AND METHOD S: The material used for the present study of 100 foetuses of different stages of gestation collected from Government maternity Hospital, Hanamkonda, ChandaKantha Memorial Hospital Warangal and private nursing h omes of Warangal D istrict of Andhra Pradesh within 10 hours of death. The dead foetuses were preserved in the hospital in 10% formalin. The foetuses were embalmed by injecting with 20 cc to 100 cc 10% formalin in to the cranial cavity and trunk depending o n the stage of gestation. Foetuses were dissected to expose small intestine and the blood vessels which supply it systematically in the following manner. OBSERVATIONS: The present study conducted has shown that length, width of small intestine was found to be increasing with foetal age. The length of celiac trunk, the length of superior mesenteric artery was found to increase proportionality with the foetal age. The causes of death in foetuses related to small intestine are intussusceptions intestional malr otation such as ladd’s bands, volvulus, cystic fibrosis, intestional infections and necrotizing enterocolitis. Knowledge related to gross anatomy and blood supply of small intestine is important because of these causes which may lead to death in foetus e s. In the present study no anomalies related to small intestine are found.

  10. A robust optimization model for blood supply chain in emergency situations

    Directory of Open Access Journals (Sweden)

    Meysam Fereiduni

    2016-09-01

    Full Text Available In this paper, a multi-period model for blood supply chain in emergency situation is presented to optimize decisions related to locate blood facilities and distribute blood products after natural disasters. In disastrous situations, uncertainty is an inseparable part of humanitarian logistics and blood supply chain as well. This paper proposes a robust network to capture the uncertain nature of blood supply chain during and after disasters. This study considers donor points, blood facilities, processing and testing labs, and hospitals as the components of blood supply chain. In addition, this paper makes location and allocation decisions for multiple post disaster periods through real data. The study compares the performances of “p-robust optimization” approach and “robust optimization” approach and the results are discussed.

  11. Delayed increases in microvascular pathology after experimental traumatic brain injury are associated with prolonged inflammation, blood-brain barrier disruption, and progressive white matter damage.

    Science.gov (United States)

    Glushakova, Olena Y; Johnson, Danny; Hayes, Ronald L

    2014-07-01

    Traumatic brain injury (TBI) is a significant risk factor for chronic traumatic encephalopathy (CTE), Alzheimer's disease (AD), and Parkinson's disease (PD). Cerebral microbleeds, focal inflammation, and white matter damage are associated with many neurological and neurodegenerative disorders including CTE, AD, PD, vascular dementia, stroke, and TBI. This study evaluates microvascular abnormalities observed at acute and chronic stages following TBI in rats, and examines pathological processes associated with these abnormalities. TBI in adult rats was induced by controlled cortical impact (CCI) of two magnitudes. Brain pathology was assessed in white matter of the corpus callosum for 24 h to 3 months following injury using immunohistochemistry (IHC). TBI resulted in focal microbleeds that were related to the magnitude of injury. At the lower magnitude of injury, microbleeds gradually increased over the 3 month duration of the study. IHC revealed TBI-induced focal abnormalities including blood-brain barrier (BBB) damage (IgG), endothelial damage (intercellular adhesion molecule 1 [ICAM-1]), activation of reactive microglia (ionized calcium binding adaptor molecule 1 [Iba1]), gliosis (glial fibrillary acidic protein [GFAP]) and macrophage-mediated inflammation (cluster of differentiation 68 [CD68]), all showing different temporal profiles. At chronic stages (up to 3 months), apparent myelin loss (Luxol fast blue) and scattered deposition of microbleeds were observed. Microbleeds were surrounded by glial scars and co-localized with CD68 and IgG puncta stainings, suggesting that localized BBB breakdown and inflammation were associated with vascular damage. Our results indicate that evolving white matter degeneration following experimental TBI is associated with significantly delayed microvascular damage and focal microbleeds that are temporally and regionally associated with development of punctate BBB breakdown and progressive inflammatory responses. Increased

  12. Intraoperative transfusion of packed red blood cells in microvascular free tissue transfer patients: assessment of 30-day morbidity using the NSQIP dataset.

    Science.gov (United States)

    Kim, Bobby D; Ver Halen, Jon P; Mlodinow, Alexei S; Kim, John Y S

    2014-02-01

    Although often a life-saving therapeutic maneuver, there is minimal data available that details the effects of intraoperative packed red blood cell transfusion (IOT) after microvascular free tissue transfer. The National Surgical Quality Improvement Program database was queried to identify all patients who underwent microvascular free tissue transfer between 2006 and 2010. Multivariate logistic regression models were used to determine the association between intraoperative transfusion and outcomes. Upon bivariate and multivariate analyses, IOT was significantly associated with higher rates of overall complications (odds ratio [OR], 2.02; 95% confidence interval [CI], 1.12-3.63), medical complications (OR, 3.35; 95% CI, 1.75-6.42), postoperative transfusion (OR, 6.02; 95% CI, 2.02-17.97), and reoperation (OR, 2.24; 95% CI, 1.24-4.04). IOT was not associated with either surgical complications or free flap loss. IOT significantly increases risk for adverse overall and medical complications. However, IOT was not associated with surgical complications or free flap loss. Transfusion practices in the operating room should be reevaluated to improve overall outcomes.

  13. Physiologic upper limits of pore size of different blood capillary types and another perspective on the dual pore theory of microvascular permeability

    Directory of Open Access Journals (Sweden)

    Sarin Hemant

    2010-08-01

    Full Text Available Abstract Background Much of our current understanding of microvascular permeability is based on the findings of classic experimental studies of blood capillary permeability to various-sized lipid-insoluble endogenous and non-endogenous macromolecules. According to the classic small pore theory of microvascular permeability, which was formulated on the basis of the findings of studies on the transcapillary flow rates of various-sized systemically or regionally perfused endogenous macromolecules, transcapillary exchange across the capillary wall takes place through a single population of small pores that are approximately 6 nm in diameter; whereas, according to the dual pore theory of microvascular permeability, which was formulated on the basis of the findings of studies on the accumulation of various-sized systemically or regionally perfused non-endogenous macromolecules in the locoregional tissue lymphatic drainages, transcapillary exchange across the capillary wall also takes place through a separate population of large pores, or capillary leaks, that are between 24 and 60 nm in diameter. The classification of blood capillary types on the basis of differences in the physiologic upper limits of pore size to transvascular flow highlights the differences in the transcapillary exchange routes for the transvascular transport of endogenous and non-endogenous macromolecules across the capillary walls of different blood capillary types. Methods The findings and published data of studies on capillary wall ultrastructure and capillary microvascular permeability to lipid-insoluble endogenous and non-endogenous molecules from the 1950s to date were reviewed. In this study, the blood capillary types in different tissues and organs were classified on the basis of the physiologic upper limits of pore size to the transvascular flow of lipid-insoluble molecules. Blood capillaries were classified as non-sinusoidal or sinusoidal on the basis of capillary wall

  14. Progress in research on the relationships among tumor blood supply patterns

    Institute of Scientific and Technical Information of China (English)

    Jie Li; Xiaobo Du

    2016-01-01

    Tumor cel growth, invasion, and metastasis require a blood supply. The diversity of tumor blood supply patterns and the biological properties of tumor cels play important roles in these processes. The discovery of vascular mimicry (VM) has enhanced the understanding of the plasticity of tumor cels and angiogenesis. VM is only a supplemental form of tumor microcirculation. However, the extensive clinical significance and special formation of VM have generated new ideas regarding anti-vascular tumor therapy. Currently, the exploration of the relationship between VM and other blood supply patterns is in the early stages, and many questions remain unanswered. Further in-depth studies of the relationships among tumor blood supply pat-terns wil identify novel anti-tumor therapeutics.

  15. Blood Supply--Susceptible Formation of Melanin Pigment in Hair Bulb Melanocytes of Mice

    Directory of Open Access Journals (Sweden)

    Shogo Maeda, MD

    2015-03-01

    Conclusions: Melanin pigment formation in the hair bulb melanocytes appeared to be susceptible to the blood supply, and melanocytosis was promoted in the follicles and in the epidermis of Kitl-Tg C57BL/6 mice.

  16. The Diagnostic Value of Superb Microvascular Imaging (SMI) in Detecting Blood Flow Signals of Breast Lesions: A Preliminary Study Comparing SMI to Color Doppler Flow Imaging.

    Science.gov (United States)

    Ma, Yan; Li, Gang; Li, Jing; Ren, Wei-dong

    2015-09-01

    The correlation between color Doppler flow imaging (CDFI) and Superb Microvascular Imaging (SMI) for detecting blood flow in breast lesions was investigated, as was the diagnostic value of SMI in differentiating benign from malignant breast lesions.These lesions were evaluated using both CDFI and SMI according to Adler's method. Pathologic examination showed 57 malignant lesions and 66 benign lesions. The number of blood vessels in a single mass was detected by 2 techniques (SMI and CDFI), and the difference between the 2 values (SMI-CDFI) was calculated. The optimal threshold for the diagnosis of malignant neoplasms and the diagnostic performances of SMI, CDFI, and SMI-CDFI were calculated.For the total lesions and malignant lesions alone, the difference between SMI and CDFI for detecting blood flow was significant (P < 0.01), but the difference was not significant for benign lesions (P = 0.15). The area under the receiver operating characteristic curve was 0.73 (95% confidence interval [CI]: 0.64-0.82) for CDFI; 0.81 (95% CI: 0.74-0.89) for SMI; and 0.89 (95% CI: 0.82-0.95) for SMI-CDFI. Furthermore, the modality of "SMI-CDFI" showed the best diagnostic performance.SMI provides further microvessel information in breast lesions. The diagnostic modality of "SMI-CDFI" can improve the diagnostic performance of ultrasound in the differentiation between benign and malignant masses.

  17. Matching supply and demand for blood in Guizhou province, China: an unresolved challenge.

    Science.gov (United States)

    Reynolds, Lucy; McKee, Martin

    2010-03-01

    Problems with blood supply in China in the 1990s stimulated measures to achieve 100% voluntary donation but supply remains inadequate to meet demand. Review of official policies, supplemented with observation of practice and interviews with key informants (potential and actual donors and health workers) in Guizhou province in Southern China. Interviewees perceived the transfusion system as a mutual social contract. However, some individuals were unwilling to donate because of concerns about health risks, the idea of transferring blood between people, wastage or profits being made from blood. Inappropriate incentives, including cash, were used to encourage donation. Recent reforms have increased confidence in donation and transfusion safety although concerns persist about misuse. There is a need to reduce unnecessary use of blood and its products. China still relies heavily on blood supplies obtained through quota, purchase or use of incentives. There is scope to expand voluntary donation further. However, as a priority it will be necessary to reduce overuse.

  18. [Intralobar pulmonary sequestration with multiple arterial blood supply].

    Science.gov (United States)

    Uroz Tristán, J; Mogueya, S A; Poenaru, D; Martínez Lagares, F; Arteaga García, R; Sanchís Solera, L; López-Pinto Ruiz, J

    1994-04-01

    We report the case of a 4 years old boy, who presented at our institution with reiterative neumonia affecting left basal lobe. Anomalous vascular appearance was detected in the chest x-ray. With the suspicion of pulmonary sequestration we carried on Digital Intravenous Angiography by Substraction (DIVAS) and aortogram. The anomalous systemic arterial supply was formed by 6 vessels coming from the thoracic aorta and going into the left lower lobe basal segment. Lobectomy was performed and previous diagnosis was confirmed pathologically.

  19. Recovery of 0.1Hz microvascular skin blood flow in dysautonomic diabetic (type 2) neuropathy by using Frequency Rhythmic Electrical Modulation System (FREMS).

    Science.gov (United States)

    Bocchi, L; Evangelisti, A; Barrella, M; Scatizzi, L; Bevilacqua, M

    2010-05-01

    Synchronized oscillation of smooth muscle cells tension in arterioles is the main control system of microvascular skin blood flow. An important autogenic vasomotion activity is recognized in 0.1Hz oscillations through power spectrum analysis of laser Doppler flowmetry. Severe dysautonomia in diabetic neuropathy is correlated with loss of 0.1Hz vasomotor activity, hence with impaired blood microcirculation. FREMS is a novel transcutaneous electrotherapy characterized by sequences of electrical stimuli of high voltage and low pulse duration which vary both in frequency and duration. We have evaluated the changes in laser Doppler flow in the volar part of the forearm before, during and after FREMS. Normal controls (n=10, 6 females, age range 21-39 years) demonstrated significant 0.1Hz vasomotion power spectra at baseline conditions associated with large oscillations of adrenergic cutaneous sweat activity sampled from the hand; people with diabetes type 2 and severe dysautonomia (n=10, 5 females, age range 63-75 years) displayed a significant decrease of 0.1Hz vasomotion power spectra. During FREMS application we observed an increase (pautonomic nervous system.

  20. A stochastic simulator of a blood product donation environment with demand spikes and supply shocks.

    Science.gov (United States)

    An, Ming-Wen; Reich, Nicholas G; Crawford, Stephen O; Brookmeyer, Ron; Louis, Thomas A; Nelson, Kenrad E

    2011-01-01

    The availability of an adequate blood supply is a critical public health need. An influenza epidemic or another crisis affecting population mobility could create a critical donor shortage, which could profoundly impact blood availability. We developed a simulation model for the blood supply environment in the United States to assess the likely impact on blood availability of factors such as an epidemic. We developed a simulator of a multi-state model with transitions among states. Weekly numbers of blood units donated and needed were generated by negative binomial stochastic processes. The simulator allows exploration of the blood system under certain conditions of supply and demand rates, and can be used for planning purposes to prepare for sudden changes in the public's health. The simulator incorporates three donor groups (first-time, sporadic, and regular), immigration and emigration, deferral period, and adjustment factors for recruitment. We illustrate possible uses of the simulator by specifying input values for an 8-week flu epidemic, resulting in a moderate supply shock and demand spike (for example, from postponed elective surgeries), and different recruitment strategies. The input values are based in part on data from a regional blood center of the American Red Cross during 1996-2005. Our results from these scenarios suggest that the key to alleviating deficit effects of a system shock may be appropriate timing and duration of recruitment efforts, in turn depending critically on anticipating shocks and rapidly implementing recruitment efforts.

  1. Venous Small Bowel Infarction: Intraoperative Laser Doppler Flowmetry Discriminates Critical Blood Supply and Spares Bowel Length

    Directory of Open Access Journals (Sweden)

    S. A. Käser

    2012-01-01

    Full Text Available Introduction. In mesenteric infarction due to arterial occlusion, laser Doppler flowmetry and spectrometry are known reliable noninvasive methods for measuring microvascular blood flow and oxygen utilisation. Case Presentation. As an innovation we used these methods in a patient with acute extensive mesenteric infarction due to venous occlusion, occurring after radical right hemicolectomy. Aiming to avoid short bowel syndrome, we spared additional 110 cm of small bowel, instead of leaving only 80 centimetres of clinically viable small bowel in situ. The pathological examination showed only 5 mm of vital mucosa to be left distal to the dissection margin. No further interventions were necessary. Conclusion. Laser doppler flowmetry and spectrometry are potentially powerful methods to assist the surgeon’s decision-making in critical venous mesenteric perfusion, thus having an important impact on clinical outcome.

  2. Pulmonary sequestration: demonstration of blood supply with 2D and 3D MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Lehnhardt, Stefan E-mail: lehn@mrs1.ukl.uni-freiburg.de; Winterer, Jan Thorsten; Uhrmeister, Peter; Herget, Georg; Laubenberger, Joerg

    2002-10-01

    Pulmonary sequestration is a relatively rare but clinically significant congenital anomaly. This disease is a spectrum of disorders involving the pulmonary airways, the arterial supply to the lungs, the lung parenchyma and its venous drainage. Traditionally, the diagnosis of pulmonary sequestration has been made definitively with arterial angiography. It is imperative for the preoperative evaluation that the arterial supply and venous drainage of the sequestered segment is identified. Several cases of MR diagnosis and preoperative evaluation of pulmonary sequestration and blood supply have been reported. In this case, MR imaging was able to provide important information about systemic blood supply via intercostal arteries and regular venous drainage. Furthermore this imaging technique revealed a second pulmonary sequestration in the dorsal phrenicocostal sinus that was not diagnosed before.

  3. Simulation-optimization model for production planning in the blood supply chain.

    Science.gov (United States)

    Osorio, Andres F; Brailsford, Sally C; Smith, Honora K; Forero-Matiz, Sonia P; Camacho-Rodríguez, Bernardo A

    2016-06-04

    Production planning in the blood supply chain is a challenging task. Many complex factors such as uncertain supply and demand, blood group proportions, shelf life constraints and different collection and production methods have to be taken into account, and thus advanced methodologies are required for decision making. This paper presents an integrated simulation-optimization model to support both strategic and operational decisions in production planning. Discrete-event simulation is used to represent the flows through the supply chain, incorporating collection, production, storing and distribution. On the other hand, an integer linear optimization model running over a rolling planning horizon is used to support daily decisions, such as the required number of donors, collection methods and production planning. This approach is evaluated using real data from a blood center in Colombia. The results show that, using the proposed model, key indicators such as shortages, outdated units, donors required and cost are improved.

  4. The blood supply in Sub-Saharan Africa: needs, challenges, and solutions.

    Science.gov (United States)

    Lund, Troy C; Hume, Heather; Allain, Jean P; McCullough, Jeffrey; Dzik, Walter

    2013-12-01

    Sub-Saharan Africa (SSA) is burdened with a growing population and poor health care resources. Transfusion medicine is uniquely affected for SSA as a result of a combination of factors which put tremendous pressure on the blood supply. In this review, we consider these factors including: malaria, sickle cell anemia, transfusion medicine infrastructure, and past transfusion medicine policies including those which are tied to foreign aid, such as a VNRD-only practice. We also consider how SSA can overcome some of these hurdles to achieve a safe and adequate blood supply for its people through the advent of new vaccines, medications, infrastructure development, policy changes, and education.

  5. Spatial frequency-based analysis of mean red blood cell speed in single microvessels: investigation of microvascular perfusion in rat cerebral cortex.

    Directory of Open Access Journals (Sweden)

    Joonas Autio

    Full Text Available BACKGROUND: Our previous study has shown that prenatal exposure to X-ray irradiation causes cerebral hypo-perfusion during the postnatal development of central nervous system (CNS. However, the source of the hypo-perfusion and its impact on the CNS development remains unclear. The present study developed an automatic analysis method to determine the mean red blood cell (RBC speed through single microvessels imaged with two-photon microscopy in the cerebral cortex of rats prenatally exposed to X-ray irradiation (1.5 Gy. METHODOLOGY/PRINCIPAL FINDINGS: We obtained a mean RBC speed (0.9±0.6 mm/sec that ranged from 0.2 to 4.4 mm/sec from 121 vessels in the radiation-exposed rats, which was about 40% lower than that of normal rats that were not exposed. These results were then compared with the conventional method for monitoring microvascular perfusion using the arteriovenous transit time (AVTT determined by tracking fluorescent markers. A significant increase in the AVTT was observed in the exposed rats (1.9±0.6 sec as compared to the age-matched non-exposed rats (1.2±0.3 sec. The results indicate that parenchyma capillary blood velocity in the exposed rats was approximately 37% lower than in non-exposed rats. CONCLUSIONS/SIGNIFICANCE: The algorithm presented is simple and robust relative to monitoring individual RBC speeds, which is superior in terms of noise tolerance and computation time. The demonstrative results show that the method developed in this study for determining the mean RBC speed in the spatial frequency domain was consistent with the conventional transit time method.

  6. Human Brain Microvascular Endothelial Cells Derived from the BC1 iPS Cell Line Exhibit a Blood-Brain Barrier Phenotype.

    Science.gov (United States)

    Katt, Moriah E; Xu, Zinnia S; Gerecht, Sharon; Searson, Peter C

    2016-01-01

    The endothelial cells that form capillaries in the brain are highly specialized, with tight junctions that minimize paracellular transport and an array of broad-spectrum efflux pumps that make drug delivery to the brain extremely challenging. One of the major limitations in blood-brain barrier research and the development of drugs to treat central nervous system diseases is the lack of appropriate cell lines. Recent reports indicate that the derivation of human brain microvascular endothelial cells (hBMECs) from human induced pluripotent stem cells (iPSCs) may provide a solution to this problem. Here we demonstrate the derivation of hBMECs extended to two new human iPSC lines: BC1 and GFP-labeled BC1. These hBMECs highly express adherens and tight junction proteins VE-cadherin, ZO-1, occludin, and claudin-5. The addition of retinoic acid upregulates VE-cadherin expression, and results in a significant increase in transendothelial electrical resistance to physiological values. The permeabilities of tacrine, rhodamine 123, and Lucifer yellow are similar to values obtained for MDCK cells. The efflux ratio for rhodamine 123 across hBMECs is in the range 2-4 indicating polarization of efflux transporters. Using the rod assay to assess cell organization in small vessels and capillaries, we show that hBMECs resist elongation with decreasing diameter but show progressive axial alignment. The derivation of hBMECs with a blood-brain barrier phenotype from the BC1 cell line highlights that the protocol is robust. The expression of GFP in hBMECs derived from the BC1-GFP cell line provides an important new resource for BBB research.

  7. Red blood cells in sports: Effects of exercise and training on oxygen supply by red blood cells

    Directory of Open Access Journals (Sweden)

    Heimo eMairbäurl

    2013-11-01

    Full Text Available During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O2 from the lungs to the tissues and the delivery of metabolically produced CO2 to the lungs for expiration. Hemoglobin also contributes to the blood’s buffering capacity, and ATP and NO release from red blood cells contributes to vasodilation and improved blood flow to working muscle. These functions require adequate amounts of red blood cells in circulation. Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called sports anemia. This is not anemia in a clinical sense because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume. The mechanisms that increase total red blood cell mass by training are not understood fully. Despite stimulated erythropoiesis, exercise can decrease the red blood cell mass by intravascular hemolysis mainly of senescent red blood cells, which is caused by mechanical rupture when red blood cells pass through capillaries in contracting muscles, and by compression of red cells e.g. in foot soles during running or in hand palms in weightlifters. Together, these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise.

  8. Effects of Visit-to-Visit Variability in Systolic Blood Pressure on Macrovascular and Microvascular Complications in Patients With Type 2 Diabetes Mellitus: The ADVANCE Trial

    National Research Council Canada - National Science Library

    Hata, Jun; Arima, Hisatomi; Rothwell, Peter M; Woodward, Mark; Zoungas, Sophia; Anderson, Craig; Patel, Anushka; Neal, Bruce; Glasziou, Paul; Hamet, Pavel; Mancia, Giuseppe; Poulter, Neil; Williams, Bryan; MacMahon, Stephen; Chalmers, John

    2013-01-01

    ...) and maximum SBP are predictors of cardiovascular disease. However, it remains uncertain whether these parameters predict the risks of macrovascular and microvascular complications in patients with type 2 diabetes mellitus...

  9. Combined effects of routine blood pressure lowering and intensive glucose control on macrovascular and microvascular outcomes in patients with type 2 diabetes: New results from the ADVANCE trial

    National Research Council Canada - National Science Library

    Zoungas, S; Galan, B.E. de; Ninomiya, T; Grobbee, D.E; Hamet, P; Heller, S; MacMahon, S; Marre, M; Neal, B; Patel, A; Woodward, M; Chalmers, J; Cass, A; Glasziou, P; Harrap, S; Lisheng, L; Mancia, G; Pillai, A; Poulter, N; Perkovic, V; Travert, F

    2009-01-01

    ...: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) trial. Annual event rates and risks of major macrovascular and microvascular events considered jointly and separately, renal events, and death during an average...

  10. Severe familial hypercholesterolemia impairs the regulation of coronary blood flow and oxygen supply during exercise.

    Science.gov (United States)

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

    2016-11-01

    Accelerated development of coronary atherosclerosis is a defining characteristic of familial hypercholesterolemia (FH). However, the recent data highlight a significant cardiovascular risk prior to the development of critical coronary stenosis. We, therefore, examined the hypothesis that FH produces coronary microvascular dysfunction and impairs coronary vascular control at rest and during exercise in a swine model of FH. Coronary vascular responses to drug infusions and exercise were examined in chronically instrumented control and FH swine. FH swine exhibited ~tenfold elevation of plasma cholesterol and diffuse coronary atherosclerosis (20-60 % plaque burden). Similar to our recent findings in the systemic vasculature in FH swine, coronary smooth muscle nitric oxide sensitivity was increased in vivo and in vitro with maintained endothelium-dependent vasodilation in vivo in FH. At rest and during exercise, FH swine exhibited increased myocardial O2 extraction resulting in reduced coronary venous SO2 and PO2 versus control. During exercise in FH swine, the transmural distribution of coronary blood flow was unchanged; however, a shift toward anaerobic cardiac metabolism was revealed by increased coronary arteriovenous H(+) concentration gradient. This shift was associated with a worsening of cardiac efficiency (relationship between cardiac work and O2 consumption) in FH during exercise owing, in part, to a generalized reduction in stroke volume which was associated with increased left atrial pressure in FH. Our data highlight a critical role for coronary microvascular dysfunction as a contributor to impaired myocardial O2 balance, cardiac ischemia, and impaired cardiac function prior to the development of critical coronary stenosis in FH.

  11. Management of blood supply room%血站供应室管理探讨

    Institute of Scientific and Technical Information of China (English)

    莫鲜春

    2011-01-01

    In order to prevent and control in-station infection in blood supply rooms, the risk factors of infection in blood supply rooms are investigated and analyzed and the preventive and control measures of infection in blood banks are developed.Infection management in blood supply room is not standardized.The potential risks involve management system,building layout, working environment, staff quality, infection prevention awareness, operational procedures, the monitoring of various risks, etc.Strengthening blood banks supply room management is necessary to prevent and control medical infection.The comprehensive measures must be taken to effectively prevent and control infection in blood supply rooms.These measures include establishing and strictly enforcing the rules and regulations, standardized management, and increasing inspection efforts.%为了预防和控制血站供应室站内感染,本文对血站供应室站内感染隐患进行调查分析,制订预防与控制血站感染对策,发现血站供应室感染管理很不规范,存在管理制度、建筑布局与工作环境、工作人员素质、感染防范意识、操作规程、各项监测诸多隐患;加强血站供应室管理力度,有效地预防与控制医疗感染.因此,必须采取综合治理措施,建立各项规章制度并严格执行,进行规范化管理,加大检查力度,才能有效地预防与控制血站供应室站内感染.

  12. Hepatocellular carcinoma: prediction of blood supply from an intercostal artery with multidetector row computed tomography.

    Science.gov (United States)

    Kim, Min-Uk; Kim, Hyo-Cheol; Chung, Jin Wook; An, Sangbu; Seong, Nak Jong; Jae, Hwan Jun; Park, Jae Hyung

    2011-10-01

    To evaluate the ability of multidetector row computed tomography (CT) to detect blood supply from the intercostal artery in patients with hepatocellular carcinoma (HCC). Between January 2003 and December 2007, angiography of the intercostal artery was performed in 93 patients (76 men and 17 women, mean age 58 years) with HCC who had also undergone multidetector row CT. CT scans and digital subtraction angiograms of these patients were retrospectively reviewed by two investigators in consensus to evaluate tumor feeding vessels. Multiple logistic regression analysis was used to identify factors that predict the presence of an HCC blood supply from an intercostal artery. Tumor staining fed by an intercostal artery was noted in 65 patients (70%; 112 tumor feeding vessels) by intercostal angiography. Readers interpreted that tumor feeding vessels were evident by CT in 35 (54%) of these 65 patients with tumor staining supplied by an intercostal artery by angiography. Multiple logistic regression analysis showed that a visible tumor feeding vessel by CT (P = .003) and hepatic artery attenuation by angiography (P = .014) were significantly related to the presence of a blood supply from an intercostal artery. Visualization of a tumor feeding vessel from the intercostal artery by multidetector row CT is an important sign of parasitic supply to an HCC. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

  13. Comparative study of the microvascular blood flow in the intestinal wall, wound contraction and fluid evacuation during negative pressure wound therapy in laparostomy using the V.A.C. abdominal dressing and the ABThera open abdomen negative pressure therapy system.

    Science.gov (United States)

    Lindstedt, Sandra; Malmsjö, Malin; Hlebowicz, Joanna; Ingemansson, Richard

    2015-02-01

    This study aimed to compare the changes in microvascular blood flow in the small intestinal wall, wound contraction and fluid evacuation, using the established V.A.C. abdominal dressing (VAC dressing) and a new abdominal dressing, the ABThera open abdomen negative pressure therapy system (ABThera dressing), in negative pressure wound therapy (NPWT). Midline incisions were made in 12 pigs that were subjected to treatment with NPWT using the VAC or ABThera dressing. The microvascular blood flow in the intestinal wall was measured before and after the application of topical negative pressures of −50, −75 and −125mmHg using laser Doppler velocimetry. Wound contraction and fluid evacuation were also measured. Baseline blood flow was defined as 100% in all settings. The blood flow was significantly reduced to 64·6±6·7% (P blood flow was significantly reduced to 39·6±6·7% (P blood flow could be observed between the two groups. The ABThera system afforded significantly better fluid evacuation from the wound, better drainage of the abdomen and better wound contraction than the VAC dressing.

  14. The arterial blood supply for the synovial tendon sheaths of the hand.

    Science.gov (United States)

    de la Garza, Oscar; Lierse, Werner; de los Angeles-García, Ma; Elizondo, Rodrigo; Guzmán, Santos

    2008-01-01

    The blood supply for the synovial tendon sheaths of the hand was carefully investigated. We show that the origin of those arteries, supplying the synovial tendon-sheaths of the Mm. flexor pollicis longus, flexor digitorum superficialis and profundus, lies in the Canalis carpi. We also describe that the branches of the Aa. digitales palmares propriae arise independently. We emphasize that the terminal branches of the A. interossea posterior and the Rete carpi dorsalis form an arterial network on the synovial tendon sheaths of the Dorsum manus. The synovial membranes of the proximal joints of the fingers receive an ample blood supply from the Rami ascendentes of the Aa. metacarpeae palmares and the Aa. digitales palmares propriae (Aa. recurrentes).

  15. [Characteristics of foot blood supply in rigidity of the great toe].

    Science.gov (United States)

    Beliaeva, A A; Kramarenko, G N; Istomina, I S

    1991-07-01

    By means of angiography, made in 20 patients with rigidity of the first toes due to osteoarthrosis, there have been revealed chronic deficiency of blood circulation in the foot tissues, especially in its antero-internal section. Blood circulation deficiency is due either to the congenital anomaly of the foot vessels or to the consequences of their traumatic injuries. Blood supply deficiency results in degenerative-dystrophic changes of the first metatarsophalangeal articulations with development of their rigidity, aggravated by post-ischemic contracture of the foot muscles.

  16. Utilizing Radiofrequency Identification Technology to Improve Safety and Management of Blood Bank Supply Chains.

    Science.gov (United States)

    Coustasse, Alberto; Meadows, Pamela; Hall, Robert S; Hibner, Travis; Deslich, Stacie

    2015-11-01

    The importance of efficiency in the supply chain of perishable products, such as the blood products used in transfusion services, cannot be overstated. Many problems can occur, such as the outdating of products, inventory management issues, patient misidentification, and mistransfusion. The purpose of this article was to identify the benefits and barriers associated with radiofrequency identification (RFID) usage in improving the blood bank supply chain. The methodology for this study was a qualitative literature review following a systematic approach. The review was limited to sources published from 2000 to 2014 in the English language. Sixty-five sources were found, and 56 were used in this research study. According to the finding of the present study, there are numerous benefits and barriers to RFID utilization in blood bank supply chains. RFID technology offers several benefits with regard to blood bank product management, including decreased transfusion errors, reduction of product loss, and more efficient inventory management. Barriers to RFID implementation include the cost associated with system implementation and patient privacy issues. Implementation of an RFID system can be a significant investment. However, when observing the positive impact that such systems may have on transfusion safety and inventory management, the cost associated with RFID systems can easily be justified. RFID in blood bank inventory management is vital to ensuring efficient product inventory management and positive patient outcomes.

  17. Opiates Upregulate Adhesion Molecule Expression in Brain MicroVascular Endothelial Cells (BMVEC: Implications for Altered Blood Brain Barrier (BBB Permeability

    Directory of Open Access Journals (Sweden)

    Madhavan P.N. Nair

    2006-01-01

    Full Text Available The blood-brain barrier (BBB is an intricate cellular system composed of vascular endothelial cells and perivascular astrocytes that restrict the passage of immunocompetent cells into the central nervous system (CNS. Expression of the adhesion molecules, intercellular adhesion molecule 1 (ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1 on brain microvascular endothelial cells (BMVEC and their interaction with human immunodeficiency virus (HIV-1 viral proteins may help enhance viral adhesion and virus-cell fusion resulting in increased infectivity. Additionally, transmigration through the BBB is facilitated by both endothelial and monocyte/macrophage-derived nitric oxide (NO. Dysregulated production of NO by BMVEC due to opiates and HIV-1 viral protein interactions play a pivotal role in brain endothelial injury, resulting in the irreversible loss of BBB integrity, which may lead to enhanced infiltration of virus-carrying cells across the BBB. Opioids act as co-factors in the neuropathogenesis of HIV-1 by facilitating BBB dysfunction however, no studies have been done to investigate the role of opiates alone or in combination with HIV-1 viral proteins on adhesion molecule expression in BMVEC. We hypothesize that opiates such as heroin and morphine in conjunction with the HIV-1 viral protein gp120 increase the expression of adhesion molecules ICAM-1 and VCAM-1 and these effects are mediated via the modulation of NO. Results show that opiates alone and in synergy with gp120 increase both the genotypic and phenotypic expression of ICAM-1 and VCAM-1 by BMVEC, additionally, these opiate induced effects may be the result of increased NO production. These studies will provide a better understanding of how opiate abuse in conjunction with HIV-1 infection facilitates the breakdown of the BBB and exacerbates the neuropathogenesis of HIV-1. Elucidation of the mechanisms of BBB modulation will provide new therapeutic approaches to maintain BBB integrity

  18. Correlations of microvascular blood flow of contrast-enhanced ultrasound and HGF/c-Met signaling pathway with clinicopathological features and prognosis of patients with hepatocellular carcinoma

    Science.gov (United States)

    Zhuang, Peng-Hui; Xu, Lei; Gao, Lu; Lu, Wei; Ruan, Li-Tao; Yang, Jin

    2017-01-01

    The study is designed to explore the correlations of microvascular blood flow of contrast-enhanced ultrasound (CEUS) and hepatocyte growth factor (HGF)/c-Met signaling pathway with clinicopathological features and prognosis of patients with hepatocellular carcinoma (HCC). One hundred and eighteen patients pathologically diagnosed as primary HCC were selected. All HCC patients underwent CEUS examination before operation. HCC tissues and adjacent normal tissue specimens were obtained to detect the protein rates of HGF and c-Met expressions by immunohistochemistry. The mRNA expressions of HGF and c-Met were detected by quantitative real-time polymerase chase reaction assay. The microvessel density (MVD) was tested by CD34 immunohistochemistry. Compared with liver parenchyma, the HCC lesions had higher MVD, preoperative peak intensity (PI), area under the curve (AUC), lower preoperative time to peak (TTP), and washout time (WOT). Compared with adjacent normal tissues, the protein and mRNA expressions of HGF were reduced in HCC tissues, but the protein and mRNA expressions of c-Met and MVD were increased. The protein expressions of HGF and c-Met exhibited evident correlations with TNM stage, tumor size, vascular invasion, liver cirrhosis, and hepatitis B virus and hepatitis C virus infection of HCC patients. The tumor size and number, vascular invasion, the protein expressions of HGF and c-Met, and MVD were associated with the TTP, PI, WOT, and AUC of CEUS in HCC patients. The protein expressions of HGF and c-Met, MVD and preoperative PI revealed negative associations with the prognosis of HCC patients. In conclusion, quantitative parameters of CEUS and HGF/c-Met signaling pathway-related proteins may be helpful for early diagnosis and prognosis prediction of HCC patients.

  19. Physiological importance of the coronary arterial blood supply to the rattlesnake heart

    DEFF Research Database (Denmark)

    Hagensen, Mette; Abe, Augusto S.; Falk, Erling;

    2008-01-01

    supply to the outer compact layer in untreated snakes. Electrocardiogram (ECG), blood pressure (Psys) and heart rate (fH) were measured at rest and during enforced activity at day 1 and 4. Four days after occlusion of the coronary circulation, the snakes could still maintain a Psys and fH of 5.2±0.2 k......Pa and 58.2±2.2 beats min-1, respectively, during activity and the ECG was not affected. This was not different from sham-operated snakes. Thus, while the outer compact layer of the rattlesnake heart clearly has an extensive coronary supply, rattlesnakes sustain a high blood pressure and heart rate during...... remains unknown. In the present study we investigate the effects of permanent coronary artery occlusion in the South American rattlesnake (Crotalus durissus) on the ability to maintain heart rate and blood pressure at rest and during short term activity. We used colored silicone rubber (Microfil...

  20. Indocyanine green fluorescent dye during bowel surgery: are the blood supply "guessing days" over?

    Science.gov (United States)

    Foppa, C; Denoya, P I; Tarta, C; Bergamaschi, R

    2014-08-01

    Assessing the blood supply of the bowel is a difficult task even for experienced surgeons. Laser-assisted indocyanine green (ICG) fluorescent dye angiography provides intraoperative visual assessment of blood flow to the bowel wall and surrounding tissues, allowing for modification to the surgical plan, which can reduce the risk of postoperative complications. ICG angiography was prospectively performed in a single center during a 1-year period for small bowel ischemia and left colorectal resections. ICG angiography played a major role in the intraoperative decision making in 4 of 160 patients, whose clinical and operative details are here reported. In case of acute small intestine ischemia, resection is not warranted unless absolute perfusion units are below 19 (relative 21%). When evaluating blood supply to the left colon prior to anastomosing, resection is recommended with absolute units lower than 18 (relative 31%) even if the bowel appears macroscopically perfused.

  1. A disturbed macrocirculatory supply as a determinant for a reduced sciatic nerve blood flow in diabetic rats

    NARCIS (Netherlands)

    Gispen, W.H.; Buren, Th. van; Kappelle, A.C.; Kasbergen, C.M.; Wildt, D.J. de

    1996-01-01

    The aim of this study was to evaluate macrocirculatory disturbances in relation to the reduced sciatic nerve blood flow seen in diabetic rats. Therefore, both femoral blood flow, the macrocirculatory arterial blood supply to the sciatic nerve, and the microcirculatory neuronal blood flow were measur

  2. Anti-Toxoplasma gondii Antibody Levels in Blood Supply of Shiraz Blood Transfusion Institute, Iran.

    Directory of Open Access Journals (Sweden)

    Minoo Shaddel

    2014-03-01

    Full Text Available The prevalence of Toxoplasma gondii infection in the blood donors has been poorly studied. The aim of this study was to assess the prevalence of acute and chronic toxoplasmosis in blood products.A total of 250 blood products (112 fresh frozen plasma and 138 packed cells in the Blood Transfusion Institute, Shiraz, Iran were tested for specific T. gondii antibodies (IgG and IgM by ELISA method in 2013. Positive IgG anti-T. gondii samples were further tested for IgM anti-T. gondii antibody. A positive IgG test with the negative and positive IgM test was interpreted as a chronic and acute toxoplasmosis, respectively. The relationship of jobs, blood types, sex, marital status and residency of participants with chronic toxoplasmosis prevalence were statistically analyzed by χ(2.Of 250 samples, 58 (23.2% and one were positive for IgG anti-T. T. gondii (chronic and IgM anti-T. T. gondii (acute antibodies levels, respectively. Twenty nine (25.9% of fresh frozen plasma (FFP samples were positive for IgG anti-T. gondiiiand 1(0.89% of them was positive for IgM anti-T. gondiii antibody. Thirty (21.74% of packed cell samples were positive for IgG anti-T. gondii antibody. The prevalence of chronic toxoplasmosis was significantly higher in workers, farmers, house wives, unemployed and free jobs (P=0.007, people with low education levels (P=0.035 and B type of blood ABO system (P=0.0001. However, there were no significant differences regarding to age, sex, marital status, residency and type of blood products.There were chronic and acute toxoplasmosis in blood products and the prevalence of toxoplasmosis especially chronic form was high. Therefore screening of blood for T. gondii antibodies may be considered.

  3. The imbalance between oxygen demand and supply as a potential mechanism in the pathophysiology of heart failure : The role of microvascular growth and abnormalities

    NARCIS (Netherlands)

    De Boer, RA; Pinto, YM; van Veldhuisen, DJ

    2003-01-01

    In heart failure., a deficient oxygen supply often is a primary cause for myocardial dysfunction. The reverse however, may also be true; the changes that occur in the failing heart may predispose for the existence of tissue hypoxia, which further affects the function of the heart. Specifically, myoc

  4. Umbilical hernia repair in conjunction with abdominoplasty: a surgical technique to maintain umbilical blood supply.

    Science.gov (United States)

    Bruner, Terrence W; Salazar-Reyes, Hector; Friedman, Jeffrey D

    2009-01-01

    Abdominal wall hernias are often diagnosed on clinical examination or encountered intraoperatively during an abdominoplasty. Traditional surgical techniques for abdominoplasty and umbilical hernia repair, when performed simultaneously, can potentially compromise the vascular supply to the umbilicus. The authors describe a simplified surgical technique for the correction of umbilical hernias in conjunction with abdominoplasty. This procedure avoids any fascial incisions immediately adjacent to the umbilicus, thereby maintaining a maximal blood supply to the umbilical stalk. Over a six-year period, 17 patients underwent the described procedure. None have had a recurrence of their hernia or umbilical necrosis, and the aesthetics of the umbilicus have been improved.

  5. [Blood supply and demand at the Fifth District Health Centre in Bamako (Mali)].

    Science.gov (United States)

    Traore, Mamadou; Dumont, Alexandre; Kaya, Amadou Balobo; Traore, Soumana Oumar; Traore, Oumar Moussokoro; Dolo, Amadou

    2011-01-01

    An adequate uncontaminated blood supply is an essential element of an effective health care system. A regional blood transfusion policy was defined in 2004 by the Direction of Health in Bamako, Mali. The objective of this study is to analyse the coverage of transfusion needs at the Fifth District health Center in Bamako after the implementation of this policy. This prospective study, conducted from December 2006 through May 2007, included 134 patients for whom transfusion orders were recorded in the laboratory. The coverage rate of transfusion needs was estimated by dividing the number of units transfused by the number of units that health professionals requested. The blood supply was regular (46 units per month, on average) and consistent with demand (59 units per month on average). Overall, 75% of the transfusions were required for obstetric complications. All patients received at least one 450-mL unit of whole blood. The coverage of transfusion needs has reached 65% of the total number of units required (95% CI = 60-70%). The implementation of a functioning system of blood transfusion is complex. In Bamako, a system based on a centralized transfusion center met a high proportion of the needs in a reference hospital where demand was high while ensuring a high level of patient safety. Further studies are needed to guide the implementation of feasible and sustainable strategies for providing sufficient quantities of safe blood in other contexts and to assess the impact of these different strategies on global health, and on maternal health in particular.

  6. Fat embolism syndrome and pulmonary microvascular cytology.

    Science.gov (United States)

    Castella, X; Vallés, J; Cabezuelo, M A; Fernandez, R; Artigas, A

    1992-06-01

    Pulmonary microvascular cytology consists of analysis of capillary blood sampled while a Swan-Ganz catheter is in the wedge position. This technique has proved to be useful in the diagnosis of lymphangitic spread of carcinoma in the lungs and there are case reports of their use in amniotic fluid embolism. Its usefulness in diagnosing fat embolism syndrome has been shown only rarely. We report a new case in which pulmonary microvascular cytologic study allowed a definite diagnosis of fat embolism syndrome. We suggest obtaining routinely samples of capillary blood when a pulmonary catheter is in place and fat embolism is suspected on a clinical basis.

  7. Hypertension: a problem of organ blood flow supply-demand mismatch.

    Science.gov (United States)

    Koeners, Maarten P; Lewis, Kirsty E; Ford, Anthony P; Paton, Julian Fr

    2016-05-01

    This review introduces a new hypothesis that sympathetically mediated hypertensive diseases are caused, in the most part, by the activation of visceral afferent systems that are connected to neural circuits generating sympathetic activity. We consider how organ hypoperfusion and blood flow supply-demand mismatch might lead to both sensory hyper-reflexia and aberrant afferent tonicity. We discuss how this may drive sympatho-excitatory-positive feedback and extend across multiple organs initiating, or at least amplifying, sympathetic hyperactivity. The latter, in turn, compounds the challenge to sufficient organ blood flow through heightened vasoconstriction that both maintains and exacerbates hypertension.

  8. UVB therapy decreases the adhesive interaction between peripheral blood mononuclear cells and dermal microvascular endothelium, and regulates the differential expression of CD54, VCAM-1, and E-selectin in psoriatic plaques

    Energy Technology Data Exchange (ETDEWEB)

    Cai, J.-P.; Harris, K.; Chin, Y.H. [Miami Univ., FL (United States). School of Medicine; Falanga, V.; Taylor, J.R. [Miami Univ., FL (United States). School of Medicine]|[Miami Veteran Affairs Medical Center, Miami, FL (United States)

    1996-01-01

    A dermal lymphocytic infiltrate is a characteristic feature of psoriasis, and may be involved in the pathogenesis of the disease. We have previously shown that specialized dermal microvascular endothelial cells (DMEC) in psoriatic lesions promote the selective adherence of the CD4 CD45Ro helper T-cell subset. In this study, we examined the adhesive interaction between peripheral blood mononuclear cells and psoriatic DMEC in patients treated with ultraviolet B light (UVB), and correlated the results with the expression and function of endothelial adhesion molecules on DMEC. (author).

  9. Blood-brain barrier permeability is positively correlated with cerebral microvascular perfusion in the early fluid percussion-injured brain of the rat.

    Science.gov (United States)

    Lin, Yong; Pan, Yaohua; Wang, Mingliang; Huang, Xianjian; Yin, Yuhua; Wang, Yu; Jia, Feng; Xiong, Wenhao; Zhang, Nu; Jiang, Ji-yao

    2012-11-01

    The blood-brain barrier (BBB) opening following traumatic brain injury (TBI) provides a chance for therapeutic agents to cross the barrier, yet the reduction of the cerebral microvascular perfusion after TBI may limit the intervention. Meanwhile, optimizing the cerebral capillary perfusion by the strategies such as fluid administration may cause brain edema due to the BBB opening post trauma. To guide the TBI therapy, we characterized the relationship between the changes in the cerebral capillary perfusion and BBB permeability after TBI. First, we observed the changes of the cerebral capillary perfusion by the intracardiac perfusion of Evans Blue and the BBB disruption with magnetic resonance imaging (MRI) in the rat subjected to lateral fluid percussion (FP) brain injury. The correlation between two variables was next evaluated with the correlation analysis. Since related to BBB breakdown, matrix metalloproteinase-9 (MMP-9) activity was finally detected by gelatin zymography. We found that the ratios of the perfused microvessel numbers in the lesioned cortices were significantly reduced at 0 and 1 h post trauma compared with that in the normal cortex, which then dramatically recovered at 4 and 24 h after injury, and that the BBB permeability was greatly augmented in the ipsilateral parts at 4, 12, and 24 h, and in the contralateral area at 24 h after injury compared with that in the uninjured brain. The correlation analysis showed that the BBB permeability increase was related to the restoration of the cerebral capillary perfusion over a 24-h period post trauma. Moreover, the gelatin zymography analysis indicated that the MMP-9 activity in the injured brain increased at 4 h and significantly elevated at 12 and 24 h as compared to that at 0 or 1 h after TBI. Our findings demonstrate that the 4 h post trauma is a critical turning point during the development of TBI, and, importantly, the correlation analysis may guide us how to treat TBI.

  10. Targeting brain microvascular endothelial cells: a therapeutic approach to neuroprotection against stroke

    Directory of Open Access Journals (Sweden)

    Qi-jin Yu

    2015-01-01

    Full Text Available Brain microvascular endothelial cells form the interface between nervous tissue and circulating blood, and regulate central nervous system homeostasis. Brain microvascular endothelial cells differ from peripheral endothelial cells with regards expression of specific ion transporters and receptors, and contain fewer fenestrations and pinocytotic vesicles. Brain microvascular endothelial cells also synthesize several factors that influence blood vessel function. This review describes the morphological characteristics and functions of brain microvascular endothelial cells, and summarizes current knowledge regarding changes in brain microvascular endothelial cells during stroke progression and therapies. Future studies should focus on identifying mechanisms underlying such changes and developing possible neuroprotective therapeutic interventions.

  11. Diagnostic examination performance by using microvascular leakage, cerebral blood volume, and blood flow derived from 3-T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in the differentiation of glioblastoma multiforme and brain metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Server, Andres; Nakstad, Per H. [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); University of Oslo, Oslo (Norway); Orheim, Tone E.D. [Oslo University Hospital, Interventional Centre, Oslo (Norway); Graff, Bjoern A. [Oslo University Hospital-Ullevaal, Department of Radiology and Nuclear Medicine, Oslo (Norway); Josefsen, Roger [Oslo University Hospital-Ullevaal, Department of Neurosurgery, Oslo (Norway); Kumar, Theresa [Oslo University Hospital-Ullevaal, Department of Pathology, Oslo (Norway)

    2011-05-15

    Conventional magnetic resonance (MR) imaging has limited capacity to differentiate between glioblastoma multiforme (GBM) and metastasis. The purposes of this study were: (1) to compare microvascular leakage (MVL), cerebral blood volume (CBV), and blood flow (CBF) in the distinction of metastasis from GBM using dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MRI), and (2) to estimate the diagnostic accuracy of perfusion and permeability MR imaging. A prospective study of 61 patients (40 GBMs and 21 metastases) was performed at 3 T using DSC-MRI. Normalized rCBV and rCBF from tumoral (rCBVt, rCBFt), peri-enhancing region (rCBVe, rCBFe), and by dividing the value in the tumor by the value in the peri-enhancing region (rCBVt/e, rCBFt/e), as well as MVL were calculated. Hemodynamic and histopathologic variables were analyzed statistically and Spearman/Pearson correlations. Receiver operating characteristic curve analysis was performed for each of the variables. The rCBVe, rCBFe, and MVL were significantly greater in GBMs compared with those of metastases. The optimal cutoff value for differentiating GBM from metastasis was 0.80 which implies a sensitivity of 95%, a specificity of 92%, a positive predictive value of 86%, and a negative predictive value of 97% for rCBVe ratio. We found a modest correlation between rCBVt and rCBFt ratios. MVL measurements in GBMs are significantly higher than those in metastases. Statistically, both rCBVe, rCBVt/e and rCBFe, rCBFt/e were useful in differentiating between GBMs and metastases, supporting the hypothesis that perfusion MR imaging can detect infiltration of tumor cells in the peri-enhancing region. (orig.)

  12. Measurements of diagnostic examination performance and correlation analysis using microvascular leakage, cerebral blood volume, and blood flow derived from 3T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in glial tumor grading

    Energy Technology Data Exchange (ETDEWEB)

    Server, Andres; Nakstad, Per H. [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); University of Oslo, Oslo (Norway); Graff, Bjoern A. [Oslo University Hospital-Ullevaal, Department of Radiology and Nuclear Medicine, Oslo (Norway); Orheim, Tone E.D.; Gadmar, Oeystein B. [Oslo University Hospital, Interventional Centre, Oslo (Norway); Schellhorn, Till [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); Josefsen, Roger [Oslo University Hospital-Ullevaal, Department of Neurosurgery, Oslo (Norway)

    2011-06-15

    To assess the diagnostic accuracy of microvascular leakage (MVL), cerebral blood volume (CBV) and blood flow (CBF) values derived from dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MR imaging) for grading of cerebral glial tumors, and to estimate the correlation between vascular permeability/perfusion parameters and tumor grades. A prospective study of 79 patients with cerebral glial tumors underwent DSC-MR imaging. Normalized relative CBV (rCBV) and relative CBF (rCBF) from tumoral (rCBVt and rCBFt), peri-enhancing region (rCBVe and rCBFe), and the value in the tumor divided by the value in the peri-enhancing region (rCBVt/e and rCBFt/e), as well as MVL, expressed as the leakage coefficient K{sub 2} were calculated. Hemodynamic variables and tumor grades were analyzed statistically and with Pearson correlations. Receiver operating characteristic (ROC) curve analyses were also performed for each of the variables. The differences in rCBVt and the maximum MVL (MVL{sub max}) values were statistically significant among all tumor grades. Correlation analysis using Pearson was as follows: rCBVt and tumor grade, r = 0.774; rCBFt and tumor grade, r = 0.417; MVL{sub max} and tumor grade, r = 0.559; MVL{sub max} and rCBVt, r = 0.440; MVL{sub max} and rCBFt, r = 0.192; and rCBVt and rCBFt, r = 0.605. According to ROC analyses for distinguishing tumor grade, rCBVt showed the largest areas under ROC curve (AUC), except for grade III from IV. Both rCBVt and MVL{sub max} showed good discriminative power in distinguishing all tumor grades. rCBVt correlated strongly with tumor grade; the correlation between MVL{sub max} and tumor grade was moderate. (orig.)

  13. The development of a canine anorectal autotransplantation model based on blood supply: a preliminary case report.

    Directory of Open Access Journals (Sweden)

    Jun Araki

    Full Text Available Colostomy is conventionally the only treatment for anal dysfunction. Recently, a few trials of anorectal transplantation in animals have been published; however, further development of this technique is required. Moreover, it is crucial to perform this research in dogs, which resemble humans in anorectal anatomy and biology. We designed a canine anorectal transplantation model, wherein anorectal autotransplantation was performed by anastomoses of the rectum, inferior mesenteric artery (IMA and vein, and pudendal nerves. Resting pressure in the anal canal and anal canal pressure fluctuation were measured before and after surgery. Graft pathology was examined three days after surgery. The anal blood supply was compared with that in three beagles using indocyanine green (ICG fluorescence angiography. The anorectal graft had sufficient arterial blood supply from the IMA; however, the graft's distal end was congested and necrotized. Functional examination demonstrated reduced resting pressure and the appearance of an irregular anal canal pressure wave after surgery. ICG angiography showed that the pudendal arteries provided more blood flow than the IMA to the anal segment. This is the first canine model of preliminary anorectal autotransplantation, and it demonstrates the possibility of establishing a transplantation model in dogs using appropriate vascular anastomoses, thus contributing to the progress of anorectal transplantation.

  14. Right hepatic artery crossing the common hepatic artery: an unusual blood supply to the liver.

    Science.gov (United States)

    Felli, Emanuele; Vennarecci, Giovanni; Santoro, Roberto; Guglielmo, Nicola; Ettorre, Giuseppe Maria

    2016-04-01

    To perform hepatic surgery a precise preoperative and intraoperative study of liver vascular supply is mandatory. Detecting vascular variations may have great importance on surgical strategy and outcome, and details of anatomy do not concern only academical knowledge but become deeply involved in practice. We present a case of unusual blood supply to the liver, the common hepatic artery was directed to the right liver and a right hepatic artery originating from the superior mesenteric artery was directed to the left liver. The right hepatic artery crossed the common hepatic artery in the proximal part of the hepatic pedicle, anterior to the portal vein. To our knowledge this type of anatomical variation has not been described before and it represents a rare finding that has to be kept in mind, especially in case of major hepatectomies and more demanding splitting liver procedures such as A.L.P.P.S., in situ split, ex situ split and living donor liver transplantation.

  15. Blood Supply Amount of Blood Banks in Chengdu,2006-2008%2006-2008年成都市储血库用血量分析

    Institute of Scientific and Technical Information of China (English)

    陈迎春; 达果; 田伟; 李晓峰

    2011-01-01

    Objective To understand the supplying of main blood products of 15 blood banks in Chengdu from 2006 to 2008, and provide reference for the blood center to further promote the use of blood components.Methods The statistical analysis was conducted on the data of blood supply in the 15 blood centers. Results From 2006 to 2008, the average supply amounts of blood plasma in the 15 blood centers were769. 67 U, 1135. 63 U and 1 783. 47 U respectively; the average supply amounts of red blood cell were 2 143. 40 U, 2678. 33 U and 3 398. 87 U respectively. Conclusion The supplying of blood components in the 15 blood banks in Chengdu increased during this period.%目的 了解成都市15个储血库主要血液制品3年的使用情况,为血液中心进一步推广成分血的应用提供参考.方法 对15个储血库主要血液制品3年的使用数据进行统计.结果 2006-2008年成都市15个储血库血浆平均用量分别为769.67 U、1135.63 U和1783.47 U;红细胞平均用量分别为2143.40 U、2678.33 U和3398.87 U.结论 2006-2008年成都市15家储血库成分血用血量不断上升.

  16. Blood supply to the thoracolumbar spinal cord in the laboratory mouse using corrosion and dissection techniques.

    Science.gov (United States)

    Flesarova, Slavka; Mazensky, David; Teleky, Jana; Almasiova, Viera; Holovska, Katarina; Supuka, Peter

    2016-01-01

    Mice are used frequently as experimental models in the study of ischemic spinal cord injury. The aim of the present study was to describe the arterial blood supply to the thoracolumbar spinal cord in the mouse. The study was carried out on 20 adult mice using the corrosion and dissection technique. Dorsal intercostal arteries were found as branches of the thoracic aorta: as 7 pairs in 80% of cases, as 8 pairs in 15% of cases and as 9 pairs in 5% of cases. The paired lumbar arteries arising from the abdominal aorta were present as 5 pairs in all cases. Along the entire thoracic and lumbar spinal regions, we observed left-sided branches entering the ventral spinal artery in 64.2% and right-sided branches in 35.8% of cases. Along the entire thoracic and lumbar spinal regions, the branches entering the dorsal spinal arteries were left-sided in 60.8% of cases and right-sided in 39.2% of cases. We found some variations in the site of origin of the artery of Adamkiewicz and in the number of dorsal spinal arteries. Documenting the anatomical variations in spinal cord blood supply in the laboratory mouse will aid the planning of future experimental studies and in determining the clinical relevance of such studies.

  17. Effect of the high femoral osteotomy upon the vascularity and blood supply of the hip joint

    Energy Technology Data Exchange (ETDEWEB)

    Day, B.; Shim, S.S.; Leung, G.

    1984-05-01

    This investigation was done to study the effects of high femoral osteotomy upon the vascularity and blood supply of the hip and to further our knowledge of its physiologic basis. We have used established methods of study, including bone scans, microangiography, isotope clearance and perosseous venography, and based upon the results of these studies, we have reached certain conclusions. First, high femoral osteotomy increases the blood flow and vascularity in the hip joint, the femoral head and neck and the great trochanter. Second, bone scanning techniques using /sup 99m/Tc labeled diphosphonate have shown increased uptake in the femoral head and neck after high femoral osteotomy. The localization was done using a Digital Gamma III computer, and the activity on the osteotomy side at two weeks was 3.5 times as great as on the control side. By 16 weeks postoperatively, there was still two times as much activity on the osteotomy side. Third, microangiography showed increased vascularity both at the osteotomy site and in the femoral head and neck and the greater trochanter on that side. Such an increase in vascularity first became evident two weeks after osteotomy and persisted during the four month period studied. Fourth, the results of the /sup 99m/Tc diphosphonate clearance study showed a 25 per cent increase in femoral head blood flow on the operative side. Fifth, perosseous venography of the femoral head and neck showed a marked increase in venous drainage through the osteotomy site in the immediate postosteotomy stage.

  18. [Effect of tranquilizers (diazepam and chlordiazepoxide) on the blood supply and activity of the heart].

    Science.gov (United States)

    Chichikanov, G G

    1975-01-01

    The effect of diazepam (0.15 and 0.5 mg/kg) and chlordiazepoxide (1.0 and 2.0 mg/kg) on the blood supply and cardiac action were investigated in experiments on cats anesthetized with urethan and chlorasol. Both these compounds were found to lower the vascular resistance to the blood flow, to bring down the coronary circulation rate and the oxygen intake of the heart. The preparations exert a marked influence on the work of the heart and the state of hemodynamics. Diazepam causes the development of an appreciable hypertension, bradycardia and reduces the cardiac ejection. Chlordiazepoxide produces a less pronounced fall of the arterial pressure, bradycardia and reduced the cardiac ejection. Unlike chlordiazepoxide diapezam reduces the contractibility of the myocardium, this being manifested in lessening the maximum acceleration of the blood flow in the aorta and in an increase of the systolic contraction time. Inhibition of the myocardium contractility occurring under the influence of diazepam may, to a certain degree, explain more pronounced hypotension observable on administration of this preparation.

  19. Catabolism of exogenously supplied thymidine to thymine and dihydrothymine by platelets in human peripheral blood

    Energy Technology Data Exchange (ETDEWEB)

    Pero, R.W.; Johnson, D.; Olsson, A.

    1984-11-01

    The interference of platelets with the estimation of unscheduled DNA synthesis in human peripheral mononuclear leukocytes following genotoxic exposure was studied. A 96% reduction in the unscheduled DNA synthesis value was achieved by incubating (/sup 3/H)thymidine with platelet-rich plasma for 5 hr at 37 degrees. Using radioactive thymine-containing compounds, together with quantitative analyses based on thin-layer and ion-exchange chromatographies, we have shown that thymidine was converted to thymine which, in turn, was converted to dihydrothymine in platelet-rich plasma. The enzymes responsible were separated from platelet lysates by gel filtration and were identified as thymidine phosphorylase and dihydrothymine dehydrogenase. The phosphorylase reversibly catalyzed the formation of thymine from thymidine and converted bromodeoxyuridine to bromouracil. The dehydrogenase reversibly catalyzed the interconversion of thymine and dihydrothymine in a reaction dependent on NADP(H), and it was inhibited by diazouracil and by thymine. Nearly all the thymidine-catabolizing activity found in whole blood samples supplied exogenously with thymidine was accounted for by the platelets. Since most genetic toxicological tests that use blood samples do not involve removing platelets from the blood cell cultures, then it is concluded that precautions should be taken in the future to determine the influence of platelets on these test systems. This is particularly true for methods dependent on thymidine pulses such as unscheduled DNA synthesis, or those dependent on bromodeoxyuridine, such as sister chromatid exchanges, since this nucleoside is also a substrate for thymidine phosphorylase.

  20. Predicting future blood supply and demand in Japan with a Markov model: application to the sex- and age-specific probability of blood donation.

    Science.gov (United States)

    Akita, Tomoyuki; Tanaka, Junko; Ohisa, Masayuki; Sugiyama, Aya; Nishida, Kazuo; Inoue, Shingo; Shirasaka, Takuma

    2016-11-01

    Simulation studies were performed to predict the future supply and demand for blood donations, and future shortfalls. Using data from all donations in 2006 to 2009, the Markov model was applied to estimate future blood donations until 2050. Based on data concerning the actual use of blood products, the number of blood products needed was estimated based on future population projections. We estimated that the number of blood donations increased from 5,020,000 in 2008 to 5,260,000 in 2012, but will decrease to 4,770,000 units by 2025. In particular, the number of donors in their 20s and 30s decreased every year. Moreover, the number of donations required to supply blood products would have been increased from 5,390,000 in 2012 to 5,660,000 units in 2025. Thus, the estimated shortfall of blood donations is expected to increase each year from 140,000 in 2012 to 890,000 in 2025 and then more than double to 1,670,000 in 2050. If the current blood donation behaviors continue, a shortfall of blood availability is likely to occur in Japan. Insufficient blood donations are mainly related to a projected reduction in population of 20 to 30 year olds, a significant group of donors. Thus, it is crucial to recruit and retain new donors and to develop recommendations for proper use of blood products to minimize unnecessary use. This study provides useful information that can be used by governments to help ensure the adequacy of the blood supply through promoting donations and conserving blood resources. © 2016 AABB.

  1. [Blood supply as a factor regulating pacemaker activity of the rat uterine horn].

    Science.gov (United States)

    Kazarian, K V; Unanian, N G; Melkonian, N N

    2013-01-01

    Effect of ischemia of the uterine artery supplying with blood the main rhythmogenic zone (the ovarian region) of the uterine horn on parameters of activity both of this locus and of all subsequent pacemaker areas up to the uterine cervix was studied in non-pregnant rats. The most pronounced changes in characteristics of the activity (amplitude, frequency, and burst genesis duration) were revealed in the ovarian horn end. The uterine corpus and the horn cervical end were less affected by ischemia. Meanwhile, under these conditions, amplitude of the slow-wave oscillations rose more than 1.5 times. The obtained data allow us to conclude about the presence of a certain connection between the horn ovarian end and the uterine cervix. Morphological studies have revealed strong vascularization of the upper part of uterine horn.

  2. Radiopharmaceutical uptake as a marker of sternal blood supply following internal mammary artery harvesting.

    Science.gov (United States)

    Rivas, L F; Hawkins, T; Morritt, G N; Behl, R P; Griffin, S C; Brown, A H

    1994-04-01

    To evaluate the impact of internal mammary artery harvesting on sternal blood supply after open heart surgery, a conventional bone scan was performed 7 days after operation in 30 patients. After administration of 370 MBq of technetium 99 m-medronic acid complex, imaging was carried out at the level of the sternum and including the humerus as a reference. A quantitative analysis of uptake (sternum/humerus uptake index) was performed and compared in three different groups of patients: group A, ten patients who had only vein grafts or valve surgery; group B, ten patients with single internal mammary artery harvesting; and group C, ten patients with bilateral internal mammary artery harvesting. These results were compared with 24 non-surgical subjects as a control (group D). Although intervention had a significant influence in raising the uptake index of the surgical groups (A = 3.34; B = 3.09 and C = 3.48) when compared with normal subjects (D = 2.45) (P 0.05). It was concluded that the vascular supply of the sternum is not entirely dependent upon the internal mammary arteries and that mobilization of both vessels does not cause per se additional serious impact to the bone vascularization after midline sternotomy, at least beyond day 7 after operation.

  3. Predictive value of PWI for blood supply and T1-spin echo MRI for consistency of pituitary adenoma

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zengyi; He, Wenqiang; Zhao, Yao; Zhang, Qilin; Li, Shiqi; Wang, Yongfei [Fudan University, Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Shanghai (China); Shanghai Pituitary Tumor Center, Shanghai (China); Yuan, Jie; Wu, Yue; Yao, Zhenwei [Fudan University, Department of Radiology, Huashan Hospital, Shanghai Medical College, Shanghai (China); Chen, Hong [Fudan University, Department of Neuropathology, Huashan Hospital, Shanghai Medical College, Shanghai (China)

    2016-01-15

    It is a common view that consistency and blood supply of pituitary adenoma (PA) can influence the surgical effect. The aim of this study was to determine whether MRI signal intensity (SI) was correlated to the consistency or blood supply of pituitary macroadenoma. Forty eight pituitary macroadenoma patients were underwent preoperative MRI, including precontrast and contrast-enhanced (CE) T1-spin echo (T1-SE) imaging, CE-sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE) imaging, and perfusion-weighted imaging (PWI). The tumor consistency and blood supply were determined by neurosurgeons. The expression of collagen IV and MIB-1 was detected with immunohistology. The correlation of the relative SI (rSI) values (tumor to normal frontal white matter SI) and PWI data to the tumor consistency, blood supply, and the expression level of collagen IV and MIB-1 was statistically studied by Kruskal-Wallis rank test (K-W test). A significant correlation was observed between the tumor consistency and the rSI on precontrast T1-SE imaging (P = 0.004) but not on CE T1-SE and CE SPACE imaging. The expression of collagen IV was also significantly associated with rSI on T1-SE imaging (P = 0.010). The blood supply was correlated with the relative CBV (rCBV) (P = 0.030). In addition, the expression of MIB-1 was correlated with rSI of CE T1-SE imaging (P = 0.007). Our results suggest that T1-SE imaging may be a simple and useful method for predicting consistency of PA. CBV value can provide helpful information for assessing the blood supply of pituitary macroadenoma. (orig.)

  4. No difference in acute effects of supplemental v. dietary calcium on blood pressure and microvascular function in obese women challenged with a high-fat meal: a cross-over randomised study.

    Science.gov (United States)

    Ferreira, Thaís da Silva; Leal, Priscila Mansur; Antunes, Vanessa Parada; Sanjuliani, Antonio Felipe; Klein, Márcia Regina Simas Torres

    2016-11-01

    Recent studies suggest that supplemental Ca (SC) increases the risk of cardiovascular events, whereas dietary Ca (DC) decreases the risk of cardiovascular events. Although frequently consumed with meals, it remains unclear whether Ca can mitigate or aggravate the deleterious effects of a high-fat meal on cardiovascular risk factors. This study aimed to evaluate the effects of SC or DC on blood pressure (BP) and microvascular function (MVF) in the postprandial period in obese women challenged with a high-fat meal. In this cross-over controlled trial, sixteen obese women aged 20-50 years were randomly assigned to receive three test meals (2908 kJ (695 kcal); 48 % fat): high DC (HDCM; 547 mg DC), high SC (HSCM; 500 mg SC-calcium carbonate) and low Ca (LCM; 42 mg DC). BP was continuously evaluated from 15 min before to 120 min after meals by digital photoplethysmography. Before and 120 min after meals, participants underwent evaluation of serum Ca and microvascular flow after postocclusive reactive hyperaemia (PORH) by laser speckle contrast imaging. Ionised serum Ca rose significantly only after HSCM. Systolic BP increased after the three meals, whereas diastolic BP increased after LCM and HDCM. Hyperaemia peak, hyperaemia amplitude and AUC evaluated after PORH decreased with LCM. After HDCM, there was a reduction in hyperaemia peak and hyperaemia amplitude, whereas HSCM decreased only hyperaemia peak. However, comparative analyses of the effects of three test meals on serum Ca, BP and MVF revealed no significant meal×time interaction. This study suggests that in obese women SC and DC do not interfere with the effects of a high-fat meal on BP and MVF.

  5. 如何做好血源紧张时的供血工作%How Do the Blood Supply during Limited Blood Recourses

    Institute of Scientific and Technical Information of China (English)

    郭毅

    2012-01-01

    The paper pointed out that during limited blood recourses, it is very important to enhance the quality of blood management, carry on staff training, perform close cooperation of blood banks and hospitals, actively improve the quality of service for scientific and rational blood transfusion, guiding the public a correct view of voluntary blood donation, easing the contradiction between blood supply and demand.%指出在血源紧张时,加强供血质量管理,做好发血工作人员培训,密切血站与医院的合作,积极提高服务质量,对规范临床科学合理输血、引导公众正确看待无偿献血、缓解血液供需矛盾有着十分重要的作用.

  6. [Neurovascular infrahyoidal myofascial flap. Anatomic and topographic study of the innervation and blood supply].

    Science.gov (United States)

    Remmert, S; Meyer, S; Majocco, A

    1998-06-01

    The neurovascular infrahyoidal myofascial flap: An anatomical and topographical study of the innervation and blood supply. 15 cadavers had bilaterally been examined for the topography of the upper thyroid artery and vein and of the lower cervical ansa, as an axial bundle of vessels and nerves for the infrahyoidal myofascial flap. With the injection of methylene blue the vascular territories of the upper thyroid artery had been demonstrated. The upper thyroid artery and vein could be found in all cases. This artery was deriving in 47% from the external carotid artery, in 30% from the bifurcation and in 23% from the common carotid artery. The vein flowed in 43% into the facial vein and in 37% into the internal jugular vein. In the remaining 20% several segmental veins were found, which flowed into the jugular vein separately. In case of a far caudally situated vascular bundle the radius of rotation can be limited in cranial direction. The voluntary innervation of the muscles of this flap is derived from the lower cervical ansa. The upper radix of the ansa can be found 1 cm in latero-cranial direction of the greater horn of the hyoid bone, where it is separating from the hypoglossal nerve. The upper thyroid artery is supplying the infrahyoidal musculature in the whole extension from the hyoid bone to the sternum. Therefore it is possible to develop a myofascial flap of 3.5 cm x 11.5 cm in size, which is pedicled at an upper vascular and nerval bundle. Depending on the radius of rotation defects of the floor of mouth, of the tongue and of the oro- and hypopharynx can well be covered with this new neurovascular myofascial flap.

  7. Multi-Objective Algorithm for Blood Supply via Unmanned Aerial Vehicles to the Wounded in an Emergency Situation.

    Science.gov (United States)

    Wen, Tingxi; Zhang, Zhongnan; Wong, Kelvin K L

    2016-01-01

    Unmanned aerial vehicle (UAV) has been widely used in many industries. In the medical environment, especially in some emergency situations, UAVs play an important role such as the supply of medicines and blood with speed and efficiency. In this paper, we study the problem of multi-objective blood supply by UAVs in such emergency situations. This is a complex problem that includes maintenance of the supply blood's temperature model during transportation, the UAVs' scheduling and routes' planning in case of multiple sites requesting blood, and limited carrying capacity. Most importantly, we need to study the blood's temperature change due to the external environment, the heating agent (or refrigerant) and time factor during transportation, and propose an optimal method for calculating the mixing proportion of blood and appendage in different circumstances and delivery conditions. Then, by introducing the idea of transportation appendage into the traditional Capacitated Vehicle Routing Problem (CVRP), this new problem is proposed according to the factors of distance and weight. Algorithmically, we use the combination of decomposition-based multi-objective evolutionary algorithm and local search method to perform a series of experiments on the CVRP public dataset. By comparing our technique with the traditional ones, our algorithm can obtain better optimization results and time performance.

  8. Multi-Objective Algorithm for Blood Supply via Unmanned Aerial Vehicles to the Wounded in an Emergency Situation.

    Directory of Open Access Journals (Sweden)

    Tingxi Wen

    Full Text Available Unmanned aerial vehicle (UAV has been widely used in many industries. In the medical environment, especially in some emergency situations, UAVs play an important role such as the supply of medicines and blood with speed and efficiency. In this paper, we study the problem of multi-objective blood supply by UAVs in such emergency situations. This is a complex problem that includes maintenance of the supply blood's temperature model during transportation, the UAVs' scheduling and routes' planning in case of multiple sites requesting blood, and limited carrying capacity. Most importantly, we need to study the blood's temperature change due to the external environment, the heating agent (or refrigerant and time factor during transportation, and propose an optimal method for calculating the mixing proportion of blood and appendage in different circumstances and delivery conditions. Then, by introducing the idea of transportation appendage into the traditional Capacitated Vehicle Routing Problem (CVRP, this new problem is proposed according to the factors of distance and weight. Algorithmically, we use the combination of decomposition-based multi-objective evolutionary algorithm and local search method to perform a series of experiments on the CVRP public dataset. By comparing our technique with the traditional ones, our algorithm can obtain better optimization results and time performance.

  9. How to Improve Blood Supply Capacity%如何提高血液供应能力

    Institute of Scientific and Technical Information of China (English)

    王海弘; 杜方安; 林荣路; 陈琳; 王翠玲

    2012-01-01

    结合工作实践,从实行社会营销式献血招募;建立血液动态库存管理制度;完善计划用血评估机制;健全特殊用血应急预案等方面,介绍了血站提高血液供应能力的做法.%The paper introduced major measures to improve blood supply capacity of blood banks from four aspects; combined with practice, the implementation of a social marketing style recruitment of blood donation; establishment of the blood dynamic inventory management system; improvement of the assessment mechanisms of the planned blood usage; making a sound special blood use contingency plan.

  10. Obstructions in Vascular Networks: Relation Between Network Morphology and Blood Supply.

    Directory of Open Access Journals (Sweden)

    Aimee M Torres Rojas

    Full Text Available We relate vascular network structure to hemodynamics after vessel obstructions. We consider tree-like networks with a viscoelastic fluid with the rheological characteristics of blood. We analyze the network hemodynamic response, which is a function of the frequencies involved in the driving, and a measurement of the resistance to flow. This response function allows the study of the hemodynamics of the system, without the knowledge of a particular pressure gradient. We find analytical expressions for the network response, which explicitly show the roles played by the network structure, the degree of obstruction, and the geometrical place in which obstructions occur. Notably, we find that the sequence of resistances of the network without occlusions strongly determines the tendencies that the response function has with the anatomical place where obstructions are located. We identify anatomical sites in a network that are critical for its overall capacity to supply blood to a tissue after obstructions. We demonstrate that relatively small obstructions in such critical sites are able to cause a much larger decrease on flow than larger obstructions placed in non-critical sites. Our results indicate that, to a large extent, the response of the network is determined locally. That is, it depends on the structure that the vasculature has around the place where occlusions are found. This result is manifest in a network that follows Murray's law, which is in reasonable agreement with several mammalian vasculatures. For this one, occlusions in early generation vessels have a radically different effect than occlusions in late generation vessels occluding the same percentage of area available to flow. This locality implies that whenever there is a tissue irrigated by a tree-like in vivo vasculature, our model is able to interpret how important obstructions are for the irrigation of such tissue.

  11. RFID in the blood supply chain--increasing productivity, quality and patient safety.

    Science.gov (United States)

    Briggs, Lynne; Davis, Rodeina; Gutierrez, Alfonso; Kopetsky, Matthew; Young, Kassandra; Veeramani, Raj

    2009-01-01

    As part of an overall design of a new, standardized RFID-enabled blood transfusion medicine supply chain, an assessment was conducted for two hospitals: the University of Iowa Hospital and Clinics (UIHC) and Mississippi Baptist Health System (MBHS). The main objectives of the study were to assess RFID technological and economic feasibility, along with possible impacts to productivity, quality and patient safety. A step-by-step process analysis focused on the factors contributing to process "pain points" (errors, inefficiency, product losses). A process re-engineering exercise produced blueprints of RFID-enabled processes to alleviate or eliminate those pain-points. In addition, an innovative model quantifying the potential reduction in adverse patient effects as a result of RFID implementation was created, allowing improvement initiatives to focus on process areas with the greatest potential impact to patient safety. The study concluded that it is feasible to implement RFID-enabled processes, with tangible improvements to productivity and safety expected. Based on a comprehensive cost/benefit model, it is estimated for a large hospital (UIHC) to recover investment from implementation within two to three years, while smaller hospitals may need longer to realize ROI. More importantly, the study estimated that RFID technology could reduce morbidity and mortality effects substantially among patients receiving transfusions.

  12. Ambiguity of mapping the relative phase of blood pulsations

    Science.gov (United States)

    Teplov, Victor; Nippolainen, Ervin; Makarenko, Alexander A.; Giniatullin, Rashid; Kamshilin, Alexei A.

    2014-01-01

    Blood pulsation imaging (BPI) is a non-invasive optical method based on photoplethysmography (PPG). It is used for the visualization of changes in the spatial distribution of blood in the microvascular bed. BPI specifically allows measurements of the relative phase of blood pulsations and using it we detected a novel type of PPG fast waveforms, which were observable in limited areas with asynchronous regional blood supply. In all subjects studied, these fast waveforms coexisted with traditional slow waveforms of PPG. We are therefore presenting a novel lock-in image processing technique of blood pulsation imaging, which can be used for detailed temporal characterization of peripheral microcirculation. PMID:25401026

  13. Ambiguity of mapping the relative phase of blood pulsations.

    Science.gov (United States)

    Teplov, Victor; Nippolainen, Ervin; Makarenko, Alexander A; Giniatullin, Rashid; Kamshilin, Alexei A

    2014-09-01

    Blood pulsation imaging (BPI) is a non-invasive optical method based on photoplethysmography (PPG). It is used for the visualization of changes in the spatial distribution of blood in the microvascular bed. BPI specifically allows measurements of the relative phase of blood pulsations and using it we detected a novel type of PPG fast waveforms, which were observable in limited areas with asynchronous regional blood supply. In all subjects studied, these fast waveforms coexisted with traditional slow waveforms of PPG. We are therefore presenting a novel lock-in image processing technique of blood pulsation imaging, which can be used for detailed temporal characterization of peripheral microcirculation.

  14. Hepatocellular Carcinoma with Blood Supply from Parasitized Omental Artery: Angiographic Appearance And Chemoembolization

    Institute of Scientific and Technical Information of China (English)

    Song Gao; Ren-jie Yang; Jia-hong Dong

    2012-01-01

    Objective:To analyze angiographic appearance of hepatocellular carcinoma (HCC) with blood supply from parasitized omental artery (POA),and evaluate the technical feasibility,safety and therapeutic efficacy of chemoembolization via the POAs.Methods:A total of 1,221 HCC patients who had undergone chemoembolization procedures were evaluated retrospectively.The evaluated indexes included the incidence rate of POAs,success rate of superselective catheterization,post-reaction after chemoembolization,and the cumulative survival rates.Results:Totally 1,221 HCC patients had undergone 3,639 chemoembolization procedures,and 32 patients with POAs were enrolled,with 97 POAs found in 76 angiography procedures,giving an incidence rate of 2.09%.POA was observed mostly at the right lobe and left medial lobe except the segment Ⅱ,and 62 POAs underwent superselective catheterization with microcatheter,giving a success rate of 63.9%.The angiographic appearance was:(1) hypertrophic POAs participating in tumor staining (n=28); (2) stiff and distorted POA (n=11),displaced due to tumor's oppression (n=8); and (3) defective tumor staining close to either gastrocolic omentum distribution or liver capsule (n=7).In 19 patients,chemoembolization via POAs was performed successfully (A group),while the remaining 13 patients failed (B group).Except 1 acute edema pancreatitis case,no serious complication was recorded.The cumulative survival rates of 6-,12-,18-and 24-month were 78.9%,47.4%,31.6% and 21.1% respectively for A group; correspondingly,61.5%,30.g%,15.4% and 7.7%% for B group,in which 2 patients died of ruptured HCC.Conclusion:Chemoembolization with microcatheter via POAs is a relatively safe,feasible and valuable method.

  15. Monitoring in microvascular surgery.

    Science.gov (United States)

    Furnas, H; Rosen, J M

    1991-03-01

    The importance of monitoring in microvascular surgery is underscored by the high reported salvage rates of failing free flaps and replants. In this overview, we begin by defining the physiology of ischemic tissue with emphasis given to the no-reflow phenomenon and the secondary critical ischemia times. Based on the physiological changes accompanying ischemia, several variables are defined that can be monitored to reflect the vascular state of a free flap or replant. Multifarious monitoring systems are then reviewed, including clinical observation, temperature, isotope clearance, ultrasonic Doppler, laser Doppler, transcutaneous oxygen tension, reflection plethysmography, dermofluorometry, pH, electromagnetic flowmetry, serial hematocrits, interstitial fluid pressure, and magnetic resonance imaging.

  16. Microvascular dysfunction as a link between obesity, insulin resistance and hypertension.

    Science.gov (United States)

    Karaca, Ü; Schram, M T; Houben, A J H M; Muris, D M J; Stehouwer, C D A

    2014-03-01

    Impaired microvascular dilatation from any cause and impaired insulin-mediated capillary recruitment in particular result in suboptimal delivery of glucose and insulin to skeletal muscle, and subsequently impairment of glucose disposal (insulin resistance). In addition, microvascular dysfunction, through functional and/or structural arteriolar and capillary drop-out, and arteriolar constriction, increases peripheral resistance and thus blood pressure. Microvascular dysfunction may thus constitute a pathway that links insulin resistance and hypertension. Overweight and obesity may be an important cause of microvascular dysfunction. Mechanisms linking overweight and obesity to microvascular dysfunction include changes in the secretion of adipokines leading to increased levels of free fatty acids and inflammatory mediators, and decreased levels of adiponectin all of which may impair endothelial insulin signaling. Microvascular dysfunction may thus constitute a new treatment target in the prevention of type 2 diabetes mellitus and hypertension. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  17. Comparison of bacteria and fungus-binding mesh, foam and gauze as fillers in negative pressure wound therapy--pressure transduction, wound edge contraction, microvascular blood flow and fluid retention.

    Science.gov (United States)

    Malmsjö, Malin; Ingemansson, Richard; Lindstedt, Sandra; Gustafsson, Lotta

    2013-10-01

    Bacteria- and fungus-binding mesh binds with and inactivates bacteria and fungus, which makes it an interesting alternative, wound filler for negative pressure wound therapy (NPWT). This study was conducted to compare the performance of pathogen-binding mesh, foam and gauze as wound fillers in NPWT with regard to pressure transduction, fluid retention, wound contraction and microvascular blood flow. Wounds on the backs of 16 pigs were filled with pathogen-binding mesh, foam or gauze and treated with NPWT. The immediate effects of 0, -40, -60, -80 and -120 mmHg, on pressure transduction and blood flow were examined in eight pigs using laser Doppler velocimetry. Wound contraction and fluid retention were studied during 72 hours of NPWT at -80 and -120 mmHg in the other eight pigs. Pathogen-binding mesh, gauze and foam provide similar pressure transduction to the wound bed during NPWT. Blood flow was found to decrease 0.5 cm laterally from the wound edge and increase 2.5 cm from the wound edge, but was unaltered 5.0 cm from the wound edge. The increase in blood flow was similar with all wound fillers. The decrease in blood flow was more pronounced with foam than with gauze and pathogen-binding mesh. Similarly, wound contraction was more pronounced with foam, than with gauze and pathogen-binding mesh. Wound fluid retention was the same in foam and pathogen-binding mesh, while more fluid was retained in the wound when using gauze. The blood flow 0.5-5 cm from the wound edge and the contraction of the wound during NPWT were similar when using pathogen-binding mesh and gauze. Wound fluid was efficiently removed when using pathogen-binding mesh, which may explain previous findings that granulation tissue formation is more rapid under pathogen-binding mesh than under gauze. This, in combination with its pathogen-binding properties, makes this mesh an interesting wound filler for use in NPWT.

  18. Microvascularization on collared peccary placenta: a microvascular cast study [corrected] in late pregnancy.

    Science.gov (United States)

    Santos, Tatiana Carlesso; Oliveira, Moacir Franco; Dantzer, Vibeke; Miglino, Maria Angélica

    2012-07-01

    The microvascularization of the collared peccary (Tayassu tajacu) placenta was studied by vascular casts and immunolocalization of α-smooth muscle actin and vimentin, to identify the three dimensional organization and vascular flow interrelation in the microvasculature between the maternal and fetal compartments of the placentae. The immunolocalization of vimentin in the vascular endothelium and in the smooth muscle cells of blood vessels showed indented capillaries along the uterine epithelium and the trophoblast at the sides of complementary maternal and fetal microfolds, or rugae. This confers the three-dimensional structure observed in vascular casts. On the maternal side, casts demonstrated uterine folds coated by with primary and secondary ridges, and by areolae dispersed between these ridges. The arteriole runs through the center/middle of ridges, branching at the top into a microvascular network wall in a basket-like fashion. At the base of these baskets venules were formed. On the fetal side, arterioles branched centrally in the fetal rugae into a capillary network in a bulbous form, complementary to the opposite maternal depressions forming the baskets. At the base of the bulbous protrusions, the fetal venules arise. The blood vessel orientation in the materno-fetal interface of the placentae of collared peccaries suggests a blood flow pattern of the type countercurrent to cross current. The same pattern has been reported in domestic swine demonstrating that, even after 38 million years, the Tayassuidae and Suidae families exhibit similar placental morphology, which is here characterized at the microvascular level.

  19. Blood banks meet the paradox of Gabriel's Horn: what are the options to maintain supply as demand decreases?

    Science.gov (United States)

    Beckman, N; Yazer, M; Land, K; Chesneau, S; Caulfield, J

    2016-06-01

    Blood services worldwide have observed a decline in the demand for red blood cells (RBC). Despite this general decline, the demand profile has changed significantly with the demand for O D negative RBCs being maintained; whereas B D positive and AB D positive RBC demand has been reduced. In 2015, the blood type O D negative was seen in 6·3% of the combined first time donors among the five American Blood Centres involved in this study and 7·4% of first time Australian donors in 2014/2015, whereas O D negative distributions accounted for 10·5% of all red cell units issued by the American centres and 13·9% by the Australian centres. Inventory can therefore be of sufficient overall quantity but may not be adequate for the demand for units with specific blood types. Recruitment of new donors may need to become more targeted and/or financial or inventory control measures could also be required to ensure inventory matches demand. Blood Services will need to consider the available options in order to ensure that sufficiency of supply is secure and the donor panel is optimised to meet the new demand paradigm. © 2016 British Blood Transfusion Society.

  20. Microvascular Coronary Artery Spasm Presents Distinctive Clinical Features With Endothelial Dysfunction as Nonobstructive Coronary Artery Disease

    Science.gov (United States)

    Ohba, Keisuke; Sugiyama, Seigo; Sumida, Hitoshi; Nozaki, Toshimitsu; Matsubara, Junichi; Matsuzawa, Yasushi; Konishi, Masaaki; Akiyama, Eiichi; Kurokawa, Hirofumi; Maeda, Hirofumi; Sugamura, Koichi; Nagayoshi, Yasuhiro; Morihisa, Kenji; Sakamoto, Kenji; Tsujita, Kenichi; Yamamoto, Eiichiro; Yamamuro, Megumi; Kojima, Sunao; Kaikita, Koichi; Tayama, Shinji; Hokimoto, Seiji; Matsui, Kunihiko; Sakamoto, Tomohiro; Ogawa, Hisao

    2012-01-01

    Background Angina without significant stenosis, or nonobstructive coronary artery disease, attracts clinical attention. Microvascular coronary artery spasm (microvascular CAS) can cause nonobstructive coronary artery disease. We investigated the clinical features of microvascular CAS and the therapeutic efficacy of calcium channel blockers. Methods and Results Three hundred seventy consecutive, stable patients with suspected angina presenting nonobstructive coronary arteries (<50% diameter) in coronary angiography were investigated with the intracoronary acetylcholine provocation test, with simultaneous measurements of transcardiac lactate production and of changes in the quantitative coronary blood flow. We diagnosed microvascular CAS according to lactate production and a decrease in coronary blood flow without epicardial vasospasm during the acetylcholine provocation test. We prospectively followed up the patients with calcium channel blockers for microvascular coronary artery disease. We identified 50 patients with microvascular CAS who demonstrated significant impairment of the endothelium-dependent vascular response, which was assessed by coronary blood flow during the acetylcholine provocation test. Administration of isosorbide dinitrate normalized the abnormal coronary flow pattern in the patients with microvascular CAS. Multivariate logistic regression analysis indicated that female sex, a lower body mass index, minor–borderline ischemic electrocardiogram findings at rest, limited–baseline diastolic-to-systolic velocity ratio, and attenuated adenosine triphosphate–induced coronary flow reserve were independently correlated with the presence of microvascular CAS. Receiver-operating characteristics curve analysis revealed that the aforementioned 5-variable model showed good correlation with the presence of microvascular CAS (area under the curve: 0.820). No patients with microvascular CAS treated with calcium channel blockers developed cardiovascular

  1. 采供血系统的冷链管理研究%Research on Cold Chain Management of Blood Collection and Supply Sys-tem

    Institute of Scientific and Technical Information of China (English)

    贾春媛

    2016-01-01

    目的:探讨采供血系统冷链管理对血液质量和血液成分的影响。方法通过对采供血机构和用血机构的血液储存、运输等环节的管理经验,总结供血系统的冷链管理方法。结果供血系统经过规范化冷链管理,用血安全得到有效保证。结论通过对供血系统冷链管理环节的有效监控和员工责任心的培养,安全供血可得到有效保障。%Objective To study the effect of cold chain management of blood collection and supply system on blood quality and blood component. Methods The cold chain management method of blood supply system was summarized by the man-agement experience of blood storage and transfusion of blood collection and supply institutions and blood use institutions. Results The blood use security was effectively ensured after the normative cold chain management of cold chain manage-ment. Conclusion The safe blood supply is effectively ensured by the effective monitoring of cold chain management links of blood supply system and cultivating the responsibility of staff.

  2. Microvascular inflammation in atherosclerosis

    Directory of Open Access Journals (Sweden)

    Laura Vitiello

    2014-06-01

    Full Text Available Atherogenesis is the pathogenetic process leading to formation of the atheroma lesion. It is associated to a chronic inflammatory state initially stimulated by an aberrant accumulation of lipid molecules beyond the endothelial barrier. This event triggers a cascade of deleterious events mainly through immune cell stimulation with the consequent liberation of potent pro-inflammatory and tissue damaging mediators. The atherogenetic process implies marked modifications of endothelial cell functions and a radical change in the endothelial–leukocyte interaction pattern. Moreover, accumulating evidence shows an important link between microvascular and inflammatory responses and major cardiovascular risk factors. This review illustrates the current knowledge on the effects of obesity, hypercholesterolemia and diabetes on microcirculation; their pathophysiological implications will be discussed.

  3. A NEW METHOD OF SINGLE-STAGE ISLAND PLASTY BY TWO BONE AUTOGRAFTS WITH BLOOD SUPPLY IN PATIENTS WITH PSEUDOARTHROSIS OF BOTH FOREARM BONES

    Directory of Open Access Journals (Sweden)

    R. M. Tikhilov

    2010-01-01

    Full Text Available The applied topographic-anatomic studies prepared in 14 fixed and 16 unfixed preparations of upper extremity allowed to precise the details of radius blood supply with reference to possibilities of formation of bone autografts with blood supply. Due to this fact the novel method of single-stage bone plasty for pseudoarthrosis of both forearm bones was developed and successfully approved in clinic. This method proposes the formation of two periosteal-cortical grafts with blood supply and small muscle cuff in distal and middle one-thirds of radius simultaneously.

  4. Effects of Intensified Vasodilatory Antihypertensive Treatment on Renal Function, Blood supply and Oxygenation in Chronic Kidney Disease

    DEFF Research Database (Denmark)

    Khatir, Dinah Sherzad; Pedersen, Michael; Ivarsen, Per

    2015-01-01

    Background: Progression of Chronic kidney disease (CKD) may result from tissue hypoxia induced by small artery structural narrowing, with increased renal vascular resistance (RVR) and impaired blood supply. We investigated whether vasodilating therapy (VT) is superior to non-vasodilating therapy...... (nonVT) for improvement of RVR, tissue oxygenation, and preservation of kidney function. Methods: Eighty-two hypertensive grade 3-4 CKD patients (glomerular filtration rate (GFR) 36±15 ml/min/1.73 m2) were randomised to renin-angiotensin inhibition combined with either VT (amlodipine) or nonVT (beta......-blocker metoprolol). At baseline and following 18 months of therapy we determined forearm resistance by venous occlusion plethysmography. Using magnetic resonance imaging (MRI) renal artery blood flow was measured for calculation of RVR, and blood oxygen level dependent (BOLD) MRI was used as a marker of renal...

  5. Short report: screening for Trypanosoma cruzi in the blood supply by the Red Cross blood bank in Quito, Ecuador.

    Science.gov (United States)

    Grijalva, M J; Chiriboga, R; Racines, J R; Escalante, L; Rowland, E C

    1997-12-01

    The status of Chagas' disease in Ecuador is not clear. In response to reports suggesting the possibility of transfusion-associated transmission of Chagas' disease in the blood bank in Quito, the Ecuadorian Red Cross in collaboration with the Instituto Nacional de Higiene, Zona Norte and the Tropical Disease Institute of Ohio University implemented a pilot Chagas' disease screening of the donated blood in the Quito blood bank. The results of the screening showed a low incidence of seropositivity among the donors (0.01% in 1994, 0.04% in 1995, and 0.02% in 1996) to the Quito blood bank and a higher seropositivity in samples donated to smaller blood banks (0.4% in 1994, 0.28% in 1995, and 0.13% in 1996) located in areas considered endemic, as well as from at least two areas previously considered nonendemic for Chagas' disease. This report highlights the need for a comprehensive evaluation of the prevalence and distribution of Chagas' disease in Ecuador.

  6. Cerebral blood volume estimation by ferumoxytol-enhanced steady-state MRI at 9.4 T reveals microvascular impact of α1 -adrenergic receptor antibodies.

    Science.gov (United States)

    Pohlmann, Andreas; Karczewski, Peter; Ku, Min-Chi; Dieringer, Babette; Waiczies, Helmar; Wisbrun, Natali; Kox, Stefanie; Palatnik, Irina; Reimann, Henning Matthias; Eichhorn, Christina; Waiczies, Sonia; Hempel, Petra; Lemke, Bernd; Niendorf, Thoralf; Bimmler, Marion

    2014-09-01

    Cerebrovascular abnormality is frequently accompanied by cognitive dysfunctions, such as dementia. Antibodies against the α1 -adrenoceptor (α1 -AR) can be found in patients with Alzheimer's disease with cerebrovascular disease, and have been shown to affect the larger vessels of the brain in rodents. However, the impact of α1 -AR antibodies on the cerebral vasculature remains unclear. In the present study, we established a neuroimaging method to measure the relative cerebral blood volume (rCBV) in small rodents with the ultimate goal to detect changes in blood vessel density and/or vessel size induced by α1 -AR antibodies. For this purpose, mapping of R2 * and R2 was performed using MRI at 9.4 T, before and after the injection of intravascular iron oxide particles (ferumoxytol). The change in the transverse relaxation rates (ΔR2 *, ΔR2 ) showed a significant rCBV decrease in the cerebrum, cortex and hippocampus of rats (except hippocampal ΔR2 ), which was more pronounced for ΔR2 * than for ΔR2 . Immunohistological analyses confirmed that the α1 -AR antibody induced blood vessel deficiencies. Our findings support the hypothesis that α1 -AR antibodies lead to cerebral vessel damage throughout the brain, which can be monitored by MRI-derived rCBV, a non-invasive neuroimaging method. This demonstrates the value of rCBV estimation by ferumoxytol-enhanced MRI at 9.4 T, and further underlines the significance of this antibody in brain diseases involving vasculature impairments, such as dementia.

  7. Advances in microvascular decompression for hemifacial spasm

    Institute of Scientific and Technical Information of China (English)

    Zhiqiang Cui; Zhipei Ling

    2015-01-01

    Primary hemifacial spasm (HFS) is a disorder that causes frequent involuntary contractions in the muscles on one side of the face, due to a blood vessel compressing the nerve at its root exit zone (REZ) from the brainstem. Numerous prospective and retrospective case series have confirmed the efficacy of microvascular decompression (MVD) of the facial nerve in patients with HFS. However, while MVD is effective, there are still significant postoperative complications. In this paper, recent technological advances related to MVD (such as lateral spread response, brainstem auditory evokes potential, three dimensional time of flight magnetic resonance angiography, intraoperative neuroendoscopy) are reviewed for the purposes of improving MVD treatment efficacy and reducing postoperative complications.

  8. Blood microvascular organization of the nasal-associated lymphoid tissue of the guinea pig: a scanning electron microscopic study of corrosion casts.

    Directory of Open Access Journals (Sweden)

    Okada,Satoko

    1995-08-01

    Full Text Available It has previously been confirmed that the guinea pig has aggregations of 10-20 lymphoid follicles at the junction of the nasal cavity and the nasopharyngeal duct. The vascular architecture of this nasal-associated lymphoid tissue (NALT was studied by the corrosion cast/scanning electron microscope method. The NALT was supplied by branches of the inferior nasal artery. These afferent arterial branches gave off arterioles to the follicles and the interfollicular regions, where the arterioles ramified into capillaries. Some of these arterioles reached the subepithelial region to form a single-layer dense capillary network. The subepithelial capillaries gathered into short collecting venules, which in turn drained into high endothelial venules (HEV in the interfollicular region. The HEV, which also receives tributaries from the follicular and interfollicular capillary plexuses, descended in the interfollicular regions and finally flowed into the efferent veins at the bottom of the NALT. Indentations impressed by high endothelial cells (HEC were prominent on the surface of the HEV casts, and their frequency was larger in the upper course or segments than in the lower. This suggests that the incidence of HEC in the upper segments is higher than in the lower segments, and these findings are consistent with the hypothesis that some substances which are taken up into the subepithelial capillaries and transported to the venules induce differentiation and maintain of HEVs.

  9. Skin microvascular reactivity in patients with hypothyroidism.

    Science.gov (United States)

    Mihor, Ana; Gergar, Maša; Gaberšček, Simona; Lenasi, Helena

    2016-11-04

    Hypothyroidism is associated with impaired vascular function; however, little is known about its impact on microcirculation. We aimed to determine skin microvascular reactivity in hypothyroidism focusing on endothelial function and the sympathetic response. We measured skin laser Doppler (LD) flux (LDF) on the volar forearm and the finger pulp using LD flowmetry in hypothyroid patients (N = 13) and healthy controls (N = 15). Skin microvascular reactivity was assessed by a three-minute occlusion of the brachial artery, inducing postocclusive reactive hyperaemia (PRH), and by a four-minute local cooling of the hand. An electrocardiogram (ECG), digital artery blood pressure and skin temperature at the measuring sites were recorded. Baseline LDF, the digital artery blood pressure and the heart rate were comparable between patients and controls. On the other hand, patients exhibited significantly longer PRH duration, significantly higher blood pressure during cooling (unpaired t-test, p skin microcirculation and an apparent increase in sympathetic reactivity after local cooling in hypothyroid patients. Hypothyroidism induces subtle changes of some haemodynamic parameters in skin microcirculation implying altered endothelial function and altered sympathetic reactivity.

  10. Effect of Erythropoietin on Microvascular Anastomosis in Rat

    African Journals Online (AJOL)

    accelerated re-endothelialization in rat femoral arteries following microvascular anastomosis. Keywords: .... significance levels were two-tailed and set at p <. 0.05. ... vein endothelial cell (HUVEC) cultures in ... injection, to maintain a high EPO concentration in blood, the .... replacement for endothelial cells in the rabbit. Circ.

  11. Blood supply of the posterior cerebral artery by the carotid system on angiograms

    NARCIS (Netherlands)

    Jongen, JCF; Franke, CL; Soeterboek, AAJGM; Versteege, CWM; Ramos, LMP; van Gijn, J

    2002-01-01

    Background and Purpose Occipital lobe infarcts are traditionally attributed to vertebrobasilar disease. However, anatomical studies indicate that in some people the supply of the posterior cerebral artery is via the carotid system. We investigated how often such a developmental variant in the cerebr

  12. Classification of hypervascular liver lesions based on hepatic artery and portal vein blood supply coefficients calculated from triphasic CT scans.

    Science.gov (United States)

    Boas, F Edward; Kamaya, Aya; Do, Bao; Desser, Terry S; Beaulieu, Christopher F; Vasanawala, Shreyas S; Hwang, Gloria L; Sze, Daniel Y

    2015-04-01

    Perfusion CT of the liver typically involves scanning the liver at least 20 times, resulting in a large radiation dose. We developed and validated a simplified model of tumor blood supply that can be applied to standard triphasic scans and evaluated whether this can be used to distinguish benign and malignant liver lesions. Triphasic CTs of 46 malignant and 32 benign liver lesions were analyzed. For each phase, regions of interest were drawn in the arterially enhancing portion of each lesion, as well as the background liver, aorta, and portal vein. Hepatic artery and portal vein blood supply coefficients for each lesion were then calculated by expressing the enhancement curve of the lesion as a linear combination of the enhancement curves of the aorta and portal vein. Hepatocellular carcinoma (HCC) and hypervascular metastases, on average, both had increased hepatic artery coefficients compared to the background liver. Compared to HCC, benign lesions, on average, had either a greater hepatic artery coefficient (hemangioma) or a greater portal vein coefficient (focal nodular hyperplasia or transient hepatic attenuation difference). Hypervascularity with washout is a key diagnostic criterion for HCC, but it had a sensitivity of 72 % and specificity of 81 % for diagnosing malignancy in our diverse set of liver lesions. The sensitivity for malignancy was increased to 89 % by including enhancing lesions that were hypodense on all phases. The specificity for malignancy was increased to 97 % (p = 0.039) by also examining hepatic artery and portal vein blood supply coefficients, while maintaining a sensitivity of 76 %.

  13. Claudin-5 regulates blood-brain barrier permeability by modifying brain microvascular endothelial cell proliferation, migration, and adhesion to prevent lung cancer metastasis.

    Science.gov (United States)

    Ma, Shun-Chang; Li, Qi; Peng, Jia-Yi; Zhouwen, Jian-Long; Diao, Jin-Fu; Niu, Jian-Xing; Wang, Xi; Guan, Xiu-Dong; Jia, Wang; Jiang, Wen-Guo

    2017-09-29

    To investigate the roles of Claudin-5 (CLDN5) in regulating the permeability of the blood-brain barrier (BBB) during lung cancer brain metastasis. By silencing and overexpressing the CLDN5 gene in human brain vascular endothelial (hCMEC/D3) cells, we demonstrated the attenuation of cell migration ability and CLDN5's significant positive role in cell proliferation in CLDN5-overexpressing hCMEC/D3 cells and observed the opposite result in the CLDN5 knockdown group. The reinforced CLDN5 expression reduced the paracellular permeability of hCMEC/D3 cells and decreased the invasion of lung adenocarcinoma A549 cells. Overall, 1685 genes were found to be differentially expressed between the CLDN5-overexpressing cells and the control cells using the Affymetrix Human Transcriptome Array 2.0 (HTA 2.0), and the function of these genes was determined by Gene Ontology and pathway analyses. The possible biological functions of the 1685 genes include cell proliferation, adhesion molecules, and the Jak-STAT, PI3K-Akt, Wnt, and Notch signaling pathways. The identified sets of mRNAs that were specific to CLDN5-overexpressing hCMEC/D3 cells were verified by a qRT-PCR experiment. CLDN5 regulates the permeability of BBB by regulating the proliferation, migration, and permeability of hCMEC/D3 cells, especially through the cell adhesion molecule signaling pathway, to enhance the function of the tight junctions, which was involved in reducing the formation of lung cancer brain metastasis. © 2017 John Wiley & Sons Ltd.

  14. Non-invasive assessment of pulmonary blood supply after staged repair of pulmonary atresia.

    OpenAIRE

    Del Torso, S.; Kelly, M J; Kalff, V; Stellin, G; Mee, R B; Venables, A W

    1985-01-01

    Radionuclide studies were performed to determine pulmonary blood flow in six children who had undergone surgery for pulmonary atresia, ventricular septal defect, and hypoplastic pulmonary arteries with or without major aortopulmonary collateral arteries. Lung blood flow was assessed from both particle perfusion lung scans and the pulmonary and systemic phase of a radionuclide dynamic flow study. Five patients had perfusion defects identified on the particle perfusion lung scan. In three of th...

  15. Cardiovascular sex differences influencing microvascular exchange

    Science.gov (United States)

    Huxley, Virginia H.; Wang, Jianjie

    2010-01-01

    The vital role of the cardiovascular (CV) system is maintenance of body functions via the matching of exchange to tissue metabolic demand. Sex-specific differences in the regulatory mechanisms of CV function and the metabolic requirements of men and women, respectively, have been identified and appreciated. This review focuses on sex differences of parameters influencing exchange at the point of union between blood and tissue, the microvasculature. Microvascular architecture, blood pressure (hydrostatic and oncotic), and vascular permeability, therefore, are discussed in the specific context of sex in health and disorders. It is notable that when sex differences exist, they are generally subtle but significant. In the aggregate, though, they can give rise to profoundly different phenotypes. The postulated mechanisms responsible for sex differences are attributed to genomics, epigenetics, and sex hormones. Depending on specific circumstances, the effect of the combined factors can range from insignificant to lethal. Identifying and understanding key signalling mechanisms bridging genomics/sex hormones and microvascular exchange properties within the scope of this review holds significant promise for sex-specific prevention and treatment of vascular barrier dysfunction. PMID:20495187

  16. The arterial blood supply of the temporomandibular joint: an anatomical study and clinical implications

    Energy Technology Data Exchange (ETDEWEB)

    Cuccia, Antonino Marco; Caradonna, Carola; Caradonna, Domenico [Dept. of Surgical and Oncological Disciplines, University of Palermo, Palermo (Italy); Anastasi, Giuseppe; Milardi, Demetrio; Favaloro, Angelo; Caradonna, Luigi; Cutroneo, Giuseppina [Biomorphology and Biotechnologies, University of Messina, Messina (Italy); De Pietro, Anita; Angileri, Tommaso Maurizio [Villa Santa Teresa, Diagnostica per Immagini, Palermo (Italy)

    2013-03-15

    The aim of this study was to analyze three-dimensional images of the arterial supply to the temporomandibular joint. Ten patients (five men and five women, mean age 36 years) without signs or symptoms of temporomandibular disorders, who underwent contrast-enhanced computed tomographic (CT) scanning with intravenous contrast, were studied. The direct volume rendering technique of CT images was used, and a data set of images to visualize the vasculature of the human temporomandibular joint in three dimensions was created. After elaboration of the data through post-processing, the arterial supply of the temporomandibular joint was studied. The analysis revealed the superficial temporal artery, the anterior tympanic artery, the deep temporal artery, the auricular posterior artery, the transverse facial artery, the middle meningeal artery, and the maxillary artery with their branches as the main arterial sources for the lateral and medial temporomandibular joint. The direct volume rendering technique was found to be successful in the assessment of the arterial supply to the temporomandibular joint. The superficial temporal artery and maxillary artery ran along the lateral and medial sides of the condylar neck, suggesting that these arteries are at increased risk during soft-tissue procedures such as an elective arthroplasty of the temporomandibular joint.

  17. Direct emergence of the dorsospinal artery from the aorta and spinal cord blood supply. Case reports and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Siclari, Francesca [The Johns Hopkins Medical Institutions, Division of Interventional Neuroradiology, Department of Radiology and Radiological Sciences, Baltimore, MD (United States); University of Geneva, Division of Clinical Anatomy, Geneva (Switzerland); Fasel, Jean H.D. [University of Geneva, Division of Clinical Anatomy, Geneva (Switzerland); Gailloud, Philippe [The Johns Hopkins Medical Institutions, Division of Interventional Neuroradiology, Department of Radiology and Radiological Sciences, Baltimore, MD (United States)

    2006-06-15

    Direct emergence of a dorsospinal artery from the aorta is a rare anatomic variant, of which a total of seven cases have been reported. This report offers an additional angiographic observation and reviews the literature. Two observations of common intercostal trunks documented during spinal angiography are described. In the first observation, the common intercostal trunk provided complete blood supply to two adjacent vertebral levels (T11 and T12). In other words, the trunk included an intercostal branch and a dorsospinal branch for each level. In the second observation, the common intercostal trunk provided an intercostal branch for each level (T9 and T10), but only one dorsospinal branch (T10). An isolated dorsospinal artery (DA) originated separately from the aorta at the T9 level, and provided a significant contribution to the anterior spinal axis. The two reported cases illustrate the concept of ''complete'' versus ''incomplete'' common intercostal trunks. In instances where an incomplete trunk is documented, a separate DA originating directly from the aorta must be looked for. A review of the literature indicates a tendency for isolated DAs to participate in the blood supply to the spinal cord. (orig.)

  18. Pelvic magnetic resonance imaging angioanatomy of the arterial blood supply to the penis in suspected prostate cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Thai, Cao Tan, E-mail: bstanhatinh@gmail.com [Department of Urology, Brabois Hospital, University Hospital of Nancy, Rue du Morvan, 54500 Vandoeuvre Lès Nancy Cedex (France); IADI Laboratory, INSERM-U947, Brabois Hospital, University Hospital of Nancy, Tour Drouet, rue du Morvan, 54511 Vandoeuvre Lès Nancy Cedex (France); Karam, Ibrahim Michel [Clinical Epidemiology and Evaluation Department, University Hospital of Nancy (France); Department of Anatomy, Faculty of Medicine Nancy, 9 Avenue de la Foret de haye BP, 54505 Vandoeuvre Lès Nancy Cedex (France); Nguyen-Thi, Phi Linh [Clinical Epidemiology and Evaluation Department, University Hospital of Nancy (France); INSERM, CIC-EC CIE6, 92 Avenue du Maréchal de Lattre de Tassigny, 54000 Nancy (France); Lefèvre, Frédéric [Department of Radiology, Brabois Hospital, University Hospital of Nancy, Rue du Morvan, 54500 Vandoeuvre Lès Nancy Cedex (France); Hubert, Jacques [Department of Urology, Brabois Hospital, University Hospital of Nancy, Rue du Morvan, 54500 Vandoeuvre Lès Nancy Cedex (France); IADI Laboratory, INSERM-U947, Brabois Hospital, University Hospital of Nancy, Tour Drouet, rue du Morvan, 54511 Vandoeuvre Lès Nancy Cedex (France); Felblinger, Jacques [IADI Laboratory, INSERM-U947, Brabois Hospital, University Hospital of Nancy, Tour Drouet, rue du Morvan, 54511 Vandoeuvre Lès Nancy Cedex (France); Eschwège, Pascal [Department of Urology, Brabois Hospital, University Hospital of Nancy, Rue du Morvan, 54500 Vandoeuvre Lès Nancy Cedex (France)

    2015-05-15

    Highlights: • Three patterns of penile arterial supply (according to the classification of Stéphane Droupy). • Our classification about accessory pudendal artery. • Origin of accessory pudendal artery. - Abstract: Purpose: To describe the internal pudendal artery (IPA) and accessory pudendal artery (APA) detected by magnetic resonance (MR) angiography to help surgeons to find and preserve them during radical prostatectomy (RP). Materials and methods: Constrast-enhanced MR 3.0 T angiography of the pelvis were performed in 111 male patients suspected diagnosis of prostate cancer (PCa), and describe the penile arterial blood supply. Results: There are three patterns of the arterial blood supply to the penis (IPA and/or APA) accounting for 51.4%, 46.8% and 1.8% of cases, respectively. About the accessory pudendal artery (APA): 54/111 (48.6%) patients had APA with five different branching patterns, they were type I (APA bilateral symmetry): 17 (31.5%); type II (APA bilateral asymmetry): 1 (1.9%); type III (APA unilateral lateral): 13 (24%); type IV (APA unilateral apical): 21 (38.9%); type V (APA unilateral mix): 2 (3.7%). APA origin were from inferior epigastric artery (IEA): 7 (9.5%); from inferior vesical artery (IVA): 32 (43.2%); from obturator artery (OA): 35 (47.3%). Conclusion: A precise angioanatomic evalutation of arteries destined to the penis by MR angiography pre-operation for male pelvic organs will help surgeons to preserve them and contributes to reduce the erectile dysfunction after these procedures.

  19. Effects of resveratrol in pregnancy using murine models with reduced blood supply to the uterus.

    Directory of Open Access Journals (Sweden)

    Rajan Poudel

    Full Text Available Preeclampsia (PE and fetal growth restriction (FGR contribute significantly to fetal and maternal morbidity and mortality. Although the causes of PE and FGR are not fully understood, both conditions are known to be associated with impaired uterine artery blood flow. Resveratrol, a polyphenol found in a number of plants, has been shown to induce relaxation of uterine arteries in vitro as well as improve many pathological conditions associated with PE and FGR. We hypothesized that treatment of endothelial nitric oxide synthase knockout mice (eNOS⁻/⁻ and catechol-O-methyltransferase knockout mice (COMT⁻/⁻ with resveratrol during pregnancy would improve uterine artery blood flow and therefore ameliorate the PE-like phenotype and FGR in these murine models. Pregnant C57BL/6J, eNOS⁻/⁻ and COMT⁻/⁻ mice received either resveratrol supplemented diet (4 g/kg diet or control diet between gestational day (GD 0.5 and GD 18.5. Resveratrol supplementation significantly increased uterine artery blood flow velocity and fetal weight in COMT⁻/⁻ but not in eNOS⁻/⁻ mice. There were no effects of resveratrol on litter size and placental weight among the groups. In conclusion, resveratrol increased uterine artery blood flow velocity and fetal weight in COMT⁻/⁻ mice, suggesting potential as a therapeutic strategy for PE and FGR.

  20. Screening for Babesia microti in the U.S. Blood Supply.

    Science.gov (United States)

    Moritz, Erin D; Winton, Colleen S; Tonnetti, Laura; Townsend, Rebecca L; Berardi, Victor P; Hewins, Mary-Ellen; Weeks, Karen E; Dodd, Roger Y; Stramer, Susan L

    2016-12-08

    Background Babesia microti, a tickborne intraerythrocytic parasite that can be transmitted by means of blood transfusion, is responsible for the majority of cases of transfusion-transmitted babesiosis in the United States. However, no licensed test exists for screening for B. microti in donated blood. We assessed data from a large-scale, investigational product-release screening and donor follow-up program. Methods From June 2012 through September 2014, we performed arrayed fluorescence immunoassays (AFIAs) for B. microti antibodies and real-time polymerase-chain-reaction (PCR) assays for B. microti DNA on blood-donation samples obtained in Connecticut, Massachusetts, Minnesota, and Wisconsin. We determined parasite loads with the use of quantitative PCR testing and assessed infectivity by means of the inoculation of hamsters and the subsequent examination for parasitemia. Donors with test-reactive samples were followed. Using data on cases of transfusion-transmitted babesiosis, we compared the proportions of screened versus unscreened donations that were infectious. Results Of 89,153 blood-donation samples tested, 335 (0.38%) were confirmed to be positive, of which 67 (20%) were PCR-positive; 9 samples were antibody-negative (i.e., 1 antibody-negative sample per 9906 screened samples), representing 13% of all PCR-positive samples. PCR-positive samples were identified all through the year; antibody-negative infections occurred from June through September. Approximately one third of the red-cell samples from PCR-positive or high-titer AFIA-positive donations infected hamsters. Follow-up showed DNA clearance in 86% of the donors but antibody seroreversion in 8% after 1 year. In Connecticut and Massachusetts, no reported cases of transfusion-transmitted babesiosis were associated with screened donations (i.e., 0 cases per 75,331 screened donations), as compared with 14 cases per 253,031 unscreened donations (i.e., 1 case per 18,074 unscreened donations) (odds ratio, 8

  1. Sleep quality and duration are related to microvascular function: the Amsterdam Growth and Health Longitudinal Study.

    Science.gov (United States)

    Bonsen, Thomas; Wijnstok, Nienke J; Hoekstra, Trynke; Eringa, Etto C; Serné, Erik H; Smulders, Yvo M; Twisk, Jos W R

    2015-04-01

    Sleep and sleep disorders are related to cardiovascular disease, and microvascular function is an early cardiovascular disease marker. Therefore, the relationship of sleep (measured in sleep quality and duration) with microvascular function was examined in healthy adults. Sleep quality was assessed with the validated Sleep Wake Experience List (SWEL) questionnaire. Duration of sleep was self-reported in an additional question. Microvascular function was measured using nailfold capillaroscopy. Linear regression analyses were used to examine the relationship between sleep and microvascular function. Potential confounders included physical activity, smoking, blood pressure, body mass index and several biochemical parameters. Analyses were performed in 259 participants (116 men). For women reporting insufficient (sleep duration, microvascular function (post-ischaemic capillary recruitment) was significantly lower (b = -11.17; P = 0.04) compared to women reporting sufficient sleep duration. There was no relationship between sleep quality and microvascular function in females. In males, a trend towards lower capillary recruitment was found in those reporting a combination of poor sleep quality and insufficient duration (b = -7.54; P = 0.09), compared to those reporting good sleep quality as well as sufficient duration. This study suggests an association between sleep and microvascular function. Which aspects of sleep exactly affect microvascular function, and if indeed the association is different between males and females in other samples, needs further research.

  2. Isolation and Culture of Human Microvascular endothelium for comparison of the morphological and molecular characteristics of Microvascular endothelial cells under normal gravity against simulated micro gravity

    Directory of Open Access Journals (Sweden)

    Tholcopiyan L

    2010-01-01

    Full Text Available BACKGROUND: Vascular endothelial cells play a major role in wound healing and also in growth of the tumors. Angiogenesis can be a target for treating diseases that are due to either poor vascularisation or decreased blood supply as in stroke, ulcers, heart disease, etc or abnormal and increased vasculature like in tumours. Application of specific compounds that may inhibit or induce the creation of new blood vessels in the body may help in the treatment of such diseases (1. Ex vivo generation of blood vessels may offer an excellent alternative to the synthetic valves that are being currently used in cardiology. Micro gravity also referred to, as weightlessness is not essentially zero gravity but rather minimal gravity. According to cell type, micro gravity causes variety of changes in proliferation and differentiation of cells while also affecting the migration of cells and cellular functions (2, 3. Siamwala et al from AUKBC have already studied the effects of microgravity on the microvascular endothelial cells from bovine lung and macrovascular endothelial cells from the bovine pulmonary artery. It was observed that the proliferation and migration of macrovascular endothelial cells were increased in microgravity (4, 5. Nitric oxide production was also studied and observed that microgravity treatment did not change nitric oxide production by microvascular endothelial cells (4OBJECTIVE: Isolation and Comparison of culture characteristics of Human microvascular endothelium cultured conventionally and in novel nanomaterial scaffold and further study the morphological and molecular characteristics of microvascular endothelial cells under normal gravity against simulated micro gravityMATERIALS AND METHODS: The human Omentum samples were obtained using surgical procedures after informed consent. The microvascular endothelial cells were isolated following the protocol described by Scott et al (6.The isolated cells were seeded in two groups; Group I

  3. Modified Continuous Loop Technique for microvascular anastomosis

    Directory of Open Access Journals (Sweden)

    Kumar Pramod

    2001-01-01

    Full Text Available A modified method of continuous loop technique for microvascular anastomosis is described. The handling of loop is easier & even last suture is placed under vision. This makes the microvascular anastomosis easier and simpler.

  4. Microvascular Recruitment in Insulin Resistance

    DEFF Research Database (Denmark)

    Sjøberg, Kim Anker

    In this PhD work a new method for measuring microvascular recruitment was developed and evaluated, using continues real-time imaging of contrast enhanced ultrasound. Gas-filled microbubbles were infused intravenously and by taking advantage of the echogenic properties of the microbubbles the reso......In this PhD work a new method for measuring microvascular recruitment was developed and evaluated, using continues real-time imaging of contrast enhanced ultrasound. Gas-filled microbubbles were infused intravenously and by taking advantage of the echogenic properties of the microbubbles...... hormone glucagon-like-peptide-1 (GLP-1) in the microcirculation. Glucagon-like-peptide-1 analogs are drugs used for treatments of insulin resistance and type 2 diabetes but the vascular effects of GLP-1 in vivo are elusive. Here it was shown that GLP-1 rapidly increased the microvascular recruitment...

  5. Microvascular Recruitment in Insulin Resistance

    DEFF Research Database (Denmark)

    Sjøberg, Kim Anker

    the resonating sound from the microbubbles in the systemic circulation were recorded for determination of microvascular recruitment in designated muscle segments. Results showed that microvascular recruitment increased with insulin stimulation by ~30% in rats and ~40% in humans (study I). Furthermore......, it was observed that muscle contractions increased muscle perfusion rapidly by 3-4 fold and by 1-2 fold compared to basal and insulin, respectively, in both rat and human skeletal muscle (study I). The real-time contrast-enhanced ultrasound method was applied to investigate the vaso-active effect of the incretin...... hormone glucagon-like-peptide-1 (GLP-1) in the microcirculation. Glucagon-like-peptide-1 analogs are drugs used for treatments of insulin resistance and type 2 diabetes but the vascular effects of GLP-1 in vivo are elusive. Here it was shown that GLP-1 rapidly increased the microvascular recruitment...

  6. Mathematical modelling of transport of a non-diffusible indicator to estimate renal blood supply

    Energy Technology Data Exchange (ETDEWEB)

    Gelfand, I.N.; Narkevich, V.Y.

    1985-01-01

    A new method is recommended to interpret the results in radionuclide studies of renal blood flow with the mathematical modelling of transport of a non-diffusible indicator in the blood vessels. The analytic proportions are ascertained between mean transit time of indicator, mean retention time (both at impulse influence and at occurence of any signal at the input) for different forms of transport function, and impulse-shaped retention function of the studied physiological system. By means of external measuring of radioactivity this allows to estimate the mean transit time of the indicator by the studied element of hemodynamics, an index, used in classically physiological studies. The recommended system of physiological indices describes the statistic and dynamic parameters of the vessel network in each kidney adequately. The use of this method showed its efficiency on principle in 7 healthy persons and in 4 patients with clinically manifest kidney diseases. (author).

  7. The effect of foot overpronation on Achilles tendon blood supply in healthy male subjects.

    Science.gov (United States)

    Karzis, K; Kalogeris, M; Mandalidis, D; Geladas, N; Karteroliotis, K; Athanasopoulos, S

    2017-10-01

    The purpose of this study was to investigate Achilles tendon blood flow in individuals with overpronated feet during non-weight- and weight-bearing positions. Achilles tendon blood flow was measured by means of the pulsatility index (PI) and the resistance index (RI) in 15 male individuals with overpronated feet and 15 counterparts with normal feet, using power Doppler ultrasonography (PDI). Achilles tendon ultrasonographic (US) assessment was performed at its musculo-tendinous junction (MTJ), mid-tendon (MT), and osseotendinous junction (OTJ) at a non-weight-bearing relaxed position (RP) and during two-leg stance (TLS) and one-leg upright stance (OLS). PI and RI indices were significantly greater in individuals with overpronated feet compared to individuals with normal feet at the OTJ in OLS position (P MTJ in all positions (P MTJ (P < 0.001). The findings of the present study suggest that foot overpronation may affect Achilles tendon blood flow, particularly at mid-tendon, thus enhancing the possibility for injury. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Three-dimensional echo-planar cine imaging of cerebral blood supply using arterial spin labeling.

    Science.gov (United States)

    Shrestha, Manoj; Mildner, Toralf; Schlumm, Torsten; Robertson, Scott Haile; Möller, Harald

    2016-12-01

    Echo-planar imaging (EPI) with CYlindrical Center-out spatiaL Encoding (EPICYCLE) is introduced as a novel hybrid three-dimensional (3D) EPI technique. Its suitability for the tracking of a short bolus created by pseudo-continuous arterial spin labeling (pCASL) through the cerebral vasculature is demonstrated. EPICYCLE acquires two-dimensional planes of k-space along center-out trajectories. These "spokes" are rotated from shot to shot about a common axis to encode a k-space cylinder. To track a bolus of labeled blood, the same subset of evenly distributed spokes is acquired in a cine fashion after a short period of pCASL. This process is repeated for all subsets to fill the whole 3D k-space of each time frame. The passage of short pCASL boluses through the vasculature of a 3D imaging slab was successfully imaged using EPICYCLE. By choosing suitable sequence parameters, the impact of slab excitation on the bolus shape could be minimized. Parametric maps of signal amplitude, transit time, and bolus width reflected typical features of blood transport in large vessels. The EPICYCLE technique was successfully applied to track a short bolus of labeled arterial blood during its passage through the cerebral vasculature.

  9. Soft Polymers for Building up Small and Smallest Blood Supplying Systems by Stereolithography.

    Science.gov (United States)

    Meyer, Wolfdietrich; Engelhardt, Sascha; Novosel, Esther; Elling, Burkhard; Wegener, Michael; Krüger, Hartmut

    2012-03-29

    Synthesis of a homologous series of photo-polymerizable α,w-polytetrahydrofuranether-diacrylate (PTHF-DA) resins is described with characterization by NMR, GPC, DSC, soaking and rheometrical measurements. The curing speeds of the resins are determined under UV light exposure. Young's modulus and tensile strength of fully cured resins show flexible to soft material attributes dependent on the molar mass of the used linear PTHF-diacrylates. Structuring the materials by stereo lithography (SL) and multiphoton polymerization (MPP) leads to tubes and bifurcated tube systems with a diameter smaller than 2 mm aimed at small to smallest supplying systems with capillary dimensions. WST-1 biocompatibility tests ofm polymer extracts show nontoxic characteristics of the adapted polymers after a washing process. Some polymers show shape memory effect (SME).

  10. Soft Polymers for Building up Small and Smallest Blood Supplying Systems by Stereolithography

    Directory of Open Access Journals (Sweden)

    Michael Wegener

    2012-03-01

    Full Text Available Synthesis of a homologous series of photo-polymerizable α,w-polytetrahydrofuranether-diacrylate (PTHF-DA resins is described with characterization by NMR, GPC, DSC, soaking and rheometrical measurements. The curing speeds of the resins are determined under UV light exposure. Young’s modulus and tensile strength of fully cured resins show flexible to soft material attributes dependent on the molar mass of the used linear PTHF-diacrylates. Structuring the materials by stereo lithography (SL and multiphoton polymerization (MPP leads to tubes and bifurcated tube systems with a diameter smaller than 2 mm aimed at small to smallest supplying systems with capillary dimensions. WST-1 biocompatibility tests ofm polymer extracts show nontoxic characteristics of the adapted polymers after a washing process. Some polymers show shape memory effect (SME.

  11. Microvascular networks for continuous self-healing materials

    Science.gov (United States)

    Toohey, Kathleen Suzanne

    Microcapsule-based and hollow glass fiber-based self-healing composites enable a single repair of crack damage in a given location. Re-mendable polymers have demonstrated crack mending for multiple cycles, but only with heat treatment and applied pressure. We demonstrate, for the first time, the autonomic characteristics of microencapsulated systems with the ability to heal repeated damage events in a continuous self-healing coating on a microvascular substrate. A three-dimensional, interconnected microvascular network in the substrate serves as a delivery system for healing materials to heal damage in a polymer coating. Two approaches to microvascular delivery are explored: one using a fluid monomer in the network with solidphase catalyst particles in the coating, and one using two or more separate networks with two fluid healing components. In both systems, the fluid(s) flow from the microchannels into the crack plane through capillary action, and polymerization occurs to heal the crack. In the single-fluid system, a single crack in a brittle epoxy coating is healed as many as seven times, and the ability to heal continuously is limited only by the availability of catalyst. The two-part healing system contained in separate networks in a specimen has significant potential to extend the repeatability of the healing process due to the microvascular supply of both healing components. Preliminary tests of this two-part system demonstrate that multiple healing cycles are possible.

  12. Relative microvascular pressure sensing

    Science.gov (United States)

    Choi, Min; Zemp, Roger

    2016-03-01

    Microcirculation may be characterized by the vascular pressure as it is influenced by pressure-driven perfusion. Crosssections of blood vessels can be visualized by photoacoustic imaging and compressing on vessels causes deformation. The photoacoustic signals of blood, when compressed to the point of vessel collapse, may or may not vanish depending on the buckling process it undergoes. We form relative pressure images of microvessels by tracking vessel collapse as a function of externally applied pressure using photoacoustic imaging.

  13. Interactions of the gasotransmitters contribute to microvascular tone (dysregulation in the preterm neonate.

    Directory of Open Access Journals (Sweden)

    Rebecca M Dyson

    Full Text Available Hydrogen sulphide (H2S, nitric oxide (NO, and carbon monoxide (CO are involved in transitional microvascular tone dysregulation in the preterm infant; however there is conflicting evidence on the interaction of these gasotransmitters, and their overall contribution to the microcirculation in newborns is not known. The aim of this study was to measure the levels of all 3 gasotransmitters, characterise their interrelationships and elucidate their combined effects on microvascular blood flow.90 preterm neonates were studied at 24h postnatal age. Microvascular studies were performed by laser Doppler. Arterial COHb levels (a measure of CO were determined through co-oximetry. NO was measured as nitrate and nitrite in urine. H2S was measured as thiosulphate by liquid chromatography. Relationships between levels of the gasotransmitters and microvascular blood flow were assessed through partial correlation controlling for the influence of gestational age. Structural equation modelling was used to examine the combination of these effects on microvascular blood flow and derive a theoretical model of their interactions.No relationship was observed between NO and CO (p = 0.18, r = 0.18. A positive relationship between NO and H2S (p = 0.008, r = 0.28 and an inverse relationship between CO and H2S (p = 0.01, r = -0.33 exists. Structural equation modelling was used to examine the combination of these effects on microvascular blood flow. The model with the best fit is presented.The relationships between NO and H2S, and CO and H2S may be of importance in the preterm newborn, particularly as NO levels in males are associated with higher H2S levels and higher microvascular blood flow and CO in females appears to convey protection against vascular dysregulation. Here we present a theoretical model of these interactions and their overall effects on microvascular flow in the preterm newborn, upon which future mechanistic studies may be based.

  14. Anatomical study of blood supply to the cervical spinal cord in the guinea pig.

    Science.gov (United States)

    Mazensky, David; Danko, Jan; Petrovova, Eva; Flesarova, Slavka; Supuka, Peter; Supukova, Anna; Luptakova, Lenka; Purzyc, Halina

    2015-06-01

    The aim of this study was to describe the arterial arrangement of the cervical spinal cord in the guinea pig. The study was carried out on 20 adult English self guinea pigs using corrosion and dissection technique. Batson's corrosion casting kit no. 17(©) was used as a casting medium. The origin of the ventral spinal artery from the left vertebral artery was found on average in 35% of the cases and from the right vertebral artery on average in 40% of the cases. The ventral spinal artery with origin from the anastomosis of two medial branches was found on average in 25% of the cases. The presence of ventral radicular branches of rami spinales entering the ventral spinal artery in the cervical region was observed in 42% of the cases on the right side and in 58% of the cases on the left side. The presence of dorsal radicular branches of rami spinales that reached the spinal cord was observed in 63% of the cases on the left side and in 37% of the cases on the right side. The number of radicular branches supplying the spinal cord is greater in guinea pig than in humans.

  15. Intraorgan differences of blood flow, oxygen supply and glycogen content in the multilobular liver of normal and hemorrhagic rats.

    Science.gov (United States)

    Metzger, H P; Schywalsky, M

    1992-02-01

    In order to characterize intraorgan differences in blood supply of the rat liver, hepatic blood flow (HBF), surface oxygen tension (sPO2) and glycogen content of the largest and smallest lobi have been determined for normal and hemorrhagic rats (N = 68) in ketamin-xylazine anesthesia. 1. Mean HBF +/- SD of lobus sinister measured 1.07 +/- 0.23 ml/g min (n = 119 determinations, N = 9 rats); HBF of lob. caudatus dexter showed a left-shifted histogram (mean value = 0.77 ml/g.min, median = 0.72 ml/g.min, modul = 0.63 ml/g.min, p less than 0.005). 2. Mean sPO2 +/- SD of lob. sin. measured 23 +/- 6.8 mm Hg (n = 168, N = 16). The histograms of lob. caudat. dext. and sin. were left-shifted (mean value of l.c.d. = 9 mm Hg, median = 4 mm Hg, modul = 0 mm Hg, mean value of l.c.s. = 16 mm Hg, median = 17 mm Hg, modul = 0 mm Hg). Under hemorrhage sPO2 became almost zero in 91% of the measurements. 3. In response to an arterial bolus of fluorescence stained gamma-globulins, spreading of the dye showed a pronounced front and marked periportal area within lob. sin., while an irregular convective front and a much smaller area were detected within both of the lobi caudati. Under hemorrhage, intersinusoidal staining and undefined, irregular contours were observed within all lobes. 4. Compared with lob. sin. preferential glycogen depletion and partial centrilobular necrosis were detected within both of the lob. caudati while under hemorrhage the glycogen stores were empty and severe group necroses have been observed especially within the small lobi. From the data it is concluded that in comparison to lob. sin. an insufficient supply and pronounced vulnerability against hepatic ischemia exists within the small lobi caudati.

  16. Analysis of the blood supply to the post-fracture edentulous mandible: study by colour Doppler sonography.

    Science.gov (United States)

    Mancini, Júlio Cezar M A; Garcia, Márcio Ricardo Taveira; de Oliveira, Ilka Regina Souza; de Freitas, Ronaldo Rodrigues; Luz, João Gualberto C

    2016-12-01

    This study assessed the arterial blood supply to the mandible of edentulous patients treated for mandibular fractures using colour Doppler ultrasound. The blood supply of edentulous patients surgically treated for mandibular fractures (group A) and edentulous fracture-free individuals (group B) was assessed. Only the fractured sides were evaluated in the first group (N = 17), whereas each side was evaluated in the second group (N = 20). The arterial flow of six sites was assessed. The systolic-peak maximum velocity (SPV), final diastolic velocity (FDV), resistive index (RI), pulsatility index (PI), acceleration and flow direction of each artery were obtained. Additionally, the presence of local vascular obstructive factors was evaluated. The differences between groups were analysed using the Kruskal-Wallis test, which was complemented by the Mann-Whitney test, for correlations between the degree of alveolar atrophy and the study factors (p < 0.050). There was a significant decrease in the flow of certain arteries, especially the submental (SPV, p = 0.007, PI, p = 0.022, and acceleration, p = 0.015), in the fracture group. The facial artery in both groups showed lower values related to local obstructive factors (SPV, p = 0.001, FDV, p = 0.040, and PI, p = 0.030). The submental artery flow was higher (SPV, p = 0.006, and FDV, p = 0.009) in non-atrophic individuals. There was a decreased flow mainly in the submental artery, but there were no cases of major vascular injury in edentulous patients treated for mandibular fractures.

  17. Microvascular Disease After Renal Transplantation

    Directory of Open Access Journals (Sweden)

    Qi Lun Ooi

    2015-11-01

    Full Text Available Background/Aims: Individuals who reach end-stage kidney disease (CKD5 have a high risk of vascular events that persists even after renal transplantation. This study compared the prevalence and severity of microvascular disease in transplant recipients and patients with CKD5. Methods: Individuals with a renal transplant or CKD5 were recruited consecutively from renal clinics, and underwent bilateral retinal photography (Canon CR5-45, Canon. Their retinal images were deidentified and reviewed for hypertensive/microvascular signs by an ophthalmologist and a trained grader (Wong and Mitchell classification, and for vessel caliber at a grading centre using a computer-assisted method and Knudtson's modification of the Parr-Hubbard formula. Results: Ninety-two transplant recipients (median duration 6.4 years, range 0.8 to 28.8 and 70 subjects with CKD5 were studied. Transplant recipients were younger (pConclusions: Hypertensive/microvascular disease occurred just as often and was generally as severe in transplant recipients and subjects with CKD5. Microvascular disease potentially contributes to increased cardiac events post- transplantation.

  18. Microvascular decompression for trigeminal neuralgia.

    Science.gov (United States)

    Sade, Burak; Lee, Joung H

    2014-10-01

    The microvascular decompression procedure has proven to be a safe and effective option in the surgical management of neurovascular compression syndromes in general and trigeminal neuralgia in particular. This article aims to serve as an overview of the decision-making process, application of the surgical technique, and clinical outcome pertaining to this procedure.

  19. Microvascularization on collared peccary placenta

    DEFF Research Database (Denmark)

    Santos, Tatiana Carlesso; Oliveira, Moacir Franco; Dantzer, Vibeke

    2012-01-01

    into a microvascular network wall in a basket-like fashion. At the base of these baskets venules were formed. On the fetal side, arterioles branched centrally in the fetal rugae into a capillary network in a bulbous form, complementary to the opposite maternal depressions forming the baskets. At the base...

  20. Non-invasive measurement of the microvascular properties of non-dysplastic and dysplastic oral leukoplakias by use of optical spectroscopy

    NARCIS (Netherlands)

    Amelink, A.; Sterenborg, H. J. C. M.; Roodenburg, J. L. N.; Witjes, M. J. H.

    2011-01-01

    Differential Path-length Spectroscopy (DPS) was used to non-invasively determine the optical properties of oral leukoplakias in vivo. DPS yields information on microvascular parameters such as the mucosal blood content, the microvascular blood oxygenation and the average micro-vessel diameter as

  1. Non-invasive measurement of the microvascular properties of non-dysplastic and dysplastic oral leukoplakias by use of optical spectroscopy

    NARCIS (Netherlands)

    Amelink, A.; Sterenborg, H. J. C. M.; Roodenburg, J. L. N.; Witjes, M. J. H.

    2011-01-01

    Differential Path-length Spectroscopy (DPS) was used to non-invasively determine the optical properties of oral leukoplakias in vivo. DPS yields information on microvascular parameters such as the mucosal blood content, the microvascular blood oxygenation and the average micro-vessel diameter as wel

  2. Micro-CT analysis of myocardial blood supply in young and adult rats

    Science.gov (United States)

    Schaefer, Heather M.; Beighley, Patricia E.; Eaker, Diane R.; Vercnocke, Andrew J.; Ritman, Erik L.

    2009-02-01

    This study addresses whether the vasculature grows in proportion to the myocardium as the rat heart develops. The volume of myocardium and coronary vessels were estimated from micro-CT images of the hearts injected with Microfil(R) contrast agent. Young (n=5) and adult (n=5) hearts were scanned, resulting in 3D images comprised of 20μm on-a-side cubic voxels. The myocardial muscle and vessel lumen volumes were measured for all vessels 40 to 320μm in diameter by an erosion and dilation method applied to the binary images in which the contrast in the vessels were assigned "1" and all non-opacified entities were assigned "0". The average total muscle volume increases by 50%, 129.4 to 237.4mm3, from young to adult rats, while the luminal volume increases by 10%, 16.6 to 18.6mm3. The vessel volume is 12% of the total muscle volume in young and 8% in adults. For a given vessel volume, the muscle volume in the young is 82% of the muscle volume in adults. We conclude that as the heart matures, the myocardium grows more rapidly than the vasculature. This may result in greater angles of separation between vessel branches, and the increase in myocardial coronary volume. The ratio suggests either higher blood flow velocity or a lower metabolic rate in adults.

  3. Microvascular endothelial cells of the corpus luteum

    Directory of Open Access Journals (Sweden)

    Spanel-Borowski Katherina

    2003-11-01

    Full Text Available Abstract The cyclic nature of the capillary bed in the corpus luteum offers a unique experimental model to examine the life cycle of endothelial cells, involving discrete physiologically regulated steps of angiogenesis, blood vessel maturation and blood vessel regression. The granulosa cells and theca cells of the developing antral follicle and the steroidogenic cells of the corpus luteum produce and respond to angiogenic factors and vasoactive peptides. Following ovulation the neovascularization during the early stages of corpus luteum development has been compared to the rapid angiogenesis observed during tumor formation. On the other end of the spectrum, the microvascular endothelial cells are the first cells to undergo apoptosis at the onset of corpus luteum regression. Important insights on the morphology and function of luteal endothelial cells have been gained from a combination of in vitro and in vivo studies on endothelial cells. Endothelial cells communicate with cells comprising the functional unit of the corpus luteum, i.e., other vascular cells, steroidogenic cells, and immune cells. This review is designed to provide an overview of the types of endothelial cells present in the corpus luteum and their involvement in corpus luteum development and regression. Available evidence indicates that microvascular endothelial cells of the corpus luteum are not alike, and may differ during the process of angiogenesis and angioregression. The contributions of vasoactive peptides generated by the luteal endothelin-1 and the renin-angiotensin systems are discussed in context with the function of endothelial cells during corpus luteum formation and regression. The ability of two cytokines, tumor necrosis factor alpha and interferon gamma, are evaluated as paracrine mediators of endothelial cell function during angioregression. Finally, chemokines are discussed as a vital endothelial cell secretory products that contribute to the recruitment of

  4. Skeletal muscle microvascular function in girls with Turner syndrome

    OpenAIRE

    West, Sarah L.; Clodagh S. O'Gorman; Alyaa H. Elzibak; Jessica Caterini; Noseworthy, Michael D; Tammy Rayner; Jill Hamilton; Wells, Greg D.

    2014-01-01

    Background: Exercise intolerance is prevalent in individuals with Turner Syndrome (TS). We recently demonstrated that girls with TS have normal aerobic but altered skeletal muscle anaerobic metabolism compared to healthy controls (HC). The purpose of this study was to compare peripheral skeletal muscle microvascular function in girls with TS to HC after exercise. We hypothesized that girls with TS would have similar muscle blood-oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) s...

  5. Translational Medicine Study on Cardiac Microvascular Endothelial Barrier Function and Myocardial Ischemia/Re-perfusion Injury

    Institute of Scientific and Technical Information of China (English)

    Yeong Yeh Lee

    2015-01-01

    Vascular endothelial barrier is defined as the ability of endothelial cells and their components that make up the microvascular wall structure in controlling the cellular components and marco-molecular substances in blood from penetrating vascular walls. It is the place for the selective exchange of oxygen, nutrients and metabolites, and has kernel effect in maintaining myocardial micro-environmental homeostasis. In clinic, microvascular permeability is commonly used as the index for evaluating endothelial barrier function. Myocardial microvascular endothelial cells, inter-endothelial connexin and basilar membrane (BM) interact synergically to constitute the basis for barrier function, which has a selective permeability effect on interaction between nutrient substances and other myocardial cell molecules. Increase of microvascular permeability is closely associated with cardiovascular events like coronary heart disease (CHD) and myocardial ischemia, and is the risk factor for CHD attack. And deep exploration of the mechanism of endothelial permeability and positive selection of new-type re-perfusion complementary drugs for alleviating endothelial permeability can be beneifcial in improving the prognosis of patients with acute myocardial infarction (AMI). Therefore, from the view of translational medicine, this study mainly summarized the increase of microvascular permeability and its pathological signiifcance after AMI, physiological and pathological mechanisms of regulating microvascular permeability and complementary therapies for AMI re-perfusion as well as microvascular endothelial barrier function, hoping to provide a basis for improving the prognosis of patients with AMI.

  6. Translational Medicine Study on Cardiac Microvascular Endothelial Barrier Function and Myocardial Ischemia/Re-perfusion Injury

    Directory of Open Access Journals (Sweden)

    Yeong Yeh Lee

    2015-09-01

    Full Text Available Vascular endothelial barrier is defined as the ability of endothelial cells and their components that make up the microvascular wall structure in controlling the cellular components and marco-molecular substances in blood from penetrating vascular walls. It is the place for the selective exchange of oxygen, nutrients and metabolites, and has kernel effect in maintaining myocardial micro-environmental homeostasis. In clinic, microvascular permeability is commonly used as the index for evaluating endothelial barrier function. Myocardial microvascular endothelial cells, inter-endothelial connexin and basilar membrane (BM interact synergically to constitute the basis for barrier function, which has a selective permeability effect on interaction between nutrient substances and other myocardial cell molecules. Increase of microvascular permeability is closely associated with cardiovascular events like coronary heart disease (CHD and myocardial ischemia, and is the risk factor for CHD attack. And deep exploration of the mechanism of endothelial permeability and positive selection of new-type re-perfusion complementary drugs for alleviating endothelial permeability can be beneficial in improving the prognosis of patients with acute myocardial infarction (AMI. Therefore, from the view of translational medicine, this study mainly summarized the increase of microvascular permeability and its pathological significance after AMI, physiological and pathological mechanisms of regulating microvascular permeability and complementary therapies for AMI re-perfusion as well as microvascular endothelial barrier function, hoping to provide a basis for improving the prognosis of patients with AMI.

  7. Glucose supply and insulin demand dynamics of antidiabetic agents.

    Science.gov (United States)

    Monte, Scott V; Schentag, Jerome J; Adelman, Martin H; Paladino, Joseph A

    2010-03-01

    For microvascular outcomes, there is compelling historical and contemporary evidence for intensive blood glucose reduction in patients with either type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM). There is also strong evidence to support macrovascular benefit with intensive blood glucose reduction in T1DM. Similar evidence remains elusive for T2DM. Because cardiovascular outcome trials utilizing conventional algorithms to attain intensive blood glucose reduction have not demonstrated superiority to less aggressive blood glucose reduction (Action to Control Cardiovascular Risk in Diabetes; Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation; and Veterans Affairs Diabetes Trial), it should be considered that the means by which the blood glucose is reduced may be as important as the actual blood glucose. By identifying quantitative differences between antidiabetic agents on carbohydrate exposure (CE), hepatic glucose uptake (HGU), hepatic gluconeogenesis (GNG), insulin resistance (IR), peripheral glucose uptake (PGU), and peripheral insulin exposure (PIE), we created a pharmacokinetic/pharmacodynamic model to characterize the effect of the agents on the glucose supply and insulin demand dynamic. Glucose supply was defined as the cumulative percentage decrease in CE, increase in HGU, decrease in GNG, and decrease in IR, while insulin demand was defined as the cumulative percentage increase in PIE and PGU. With the glucose supply and insulin demand effects of each antidiabetic agent summated, the glucose supply (numerator) was divided by the insulin demand (denominator) to create a value representative of the glucose supply and insulin demand dynamic (SD ratio). Alpha-glucosidase inhibitors (1.25), metformin (2.20), and thiazolidinediones (TZDs; 1.25-1.32) demonstrate a greater effect on glucose supply (SD ratio >1), while secretagogues (0.69-0.81), basal insulins (0.77-0.79), and bolus insulins (0

  8. The effect of hepatic vascular exclusion on hepatic blood flow and oxygen supply--uptake ratio in the pig.

    Science.gov (United States)

    López Santamaria, M; Gamez, M; Murcia, J; Paz Cruz, J A; Bueno, J; Canser, E; Qi, B; Lobato, R; Martinez, L; Jara, P; Tovar, J A

    1997-10-01

    The hemodynamic disturbances produced by total hepatic vascular exclusion (THVE) for 40 minutes were studied in 7 pigs (19-22 kg). THVE was produced by clamping the hepatic pedicle and inferior vena cava, above and below the liver, for a 40-minutes period, followed by unclamping. Compared to baseline values, 30 minutes after onset of THVE, there was a decrease in cardiac output (3.86 +/- 0.55 vs 1.23 +/- 0.23 L x min-1), systemic arterial pressure (97.54 +/- 13.58 vs 43.43 +/- 11.38 mm Hg), and pulmonary artery pressure (16.57 +/- 6.38 vs 12.57 +/- 3.58) and an increase in systemic and pulmonary vascular resistance (1772 +/- 198 vs 2351 +/- 462, and 182 +/- 66 vs 361 +/- 124 dyn x s x cm-5 respectively). As a result of diminished cardiac output, the systemic oxygen supply decreased (461 +/- 131 vs 101 +/- 46 ml x min-1), but the systemic oxygen extraction rate rose from 17.3% t0 31.2%. Thirty minutes after unclamping, the changes had reversed and all the parameters tended to normalize. Total hepatic blood flow 30 minutes after unclamping was higher than at baseline (5.08 +/- 1.2 vs 6.66 +/- 0.67 ml x min-1 x 100 g-1), because of the increase in portal blood flow (4.52 +/- 1.21 vs 6.07 +/- 0.70 ml x min-1 x 100 g-1). There were no significant differences in hepatic oxygen supply and uptake at baseline and after unclamping (152.6 +/- 23.0 vs 187.0 +/- 34.7 and 22.7 +/- 4.9 vs 28.7 +/- 8.4 ml O2 respectively). AST rose (29 +/- 7 vs 136 +/- 91 U/l), but there was no change in the remaining liver enzymes, glucose, creatinine and serum electrolytes, so we conclude that the hemodynamic disturbances produced by 40 minutes of THVE are manageable and spontaneously reversible. Liver metabolism was not greatly disturbed, so THVE was judged to be a viable technique to be added to the surgeon's range of options.

  9. Reliability of near-infrared angiography and micro-Doppler sonography for evaluating microvascular anastomoses.

    Science.gov (United States)

    Mücke, Thomas; Wolff, Klaus-Dietrich; Wagenpfeil, Stefan; Hölzle, Frank; Scholz, Martin

    2010-11-01

    Intraoperative fluorescence angiography has been reported to be a promising method, with rapid and high-quality image production at low cost when used for the detection of microvascular complications. The purpose of this study was to evaluate the reliability of intraoperative near-infrared indocyanine green angiography compared with microvascular Doppler testing in a standardized model in the rat with different vessel patencies. The carotid, aorta, and femoral vessels of 23 Wistar rats were used. Indocyanine green angiography and microvascular Doppler sonographic testing were performed to assess microanastomosis with a vessel patency randomly narrowed at the anastomosis to an outer patency of 100, 75, 50, 25, and 0 percent. A total of 424 investigations were performed for 68 anastomoses, including both indocyanine green videoangiographic and microvascular Doppler sonographic examinations. The overall sensitivity and specificity of the microvascular Doppler sonographic testing at different degrees of stenoses were 100 and 86.9 percent, respectively. The positive predictive value for all observations was 95.8 percent, and the corresponding negative predictive value was 100 percent. Indocyanine green angiography revealed an overall sensitivity of 95.3 percent and a specificity of 100 percent. The positive predictive value for these observations was 100 percent, and the negative predictive value was 84 percent. Indocyanine green angiography and microvascular Doppler sonography are quick and reliable methods for assessing blood flow in vessels in the laboratory model. The combined use of indocyanine green angiography and microvascular Doppler sonography can increase the accuracy of assessment of microvascular anastomoses intraoperatively. Indocyanine green can be used first, but followed by the microvascular Doppler in cases of a negative result to maximize accuracy.

  10. Factor Analysis on Blood Collection and Supply in Yichang%宜昌市采供血及其相关因素分析

    Institute of Scientific and Technical Information of China (English)

    袁玉荣; 潘修银

    2015-01-01

    目的分析宜昌市中心血站2008-2013年采供血情况,并进行评价,指导今后的采供血工作。方法查阅本站计算机系统存储的信息,统计分析了采血量、报废率及各种血液成分供应量的变化情况。结果2008-2013年血站的采血总量、各种血液成分供应量呈逐年上升趋势,报废率呈逐年下降趋势。结论宜昌市中心血站采供血质量管理持续改进,成效显著,该数据分析对血站未来几年的快速发展有一定的指导作用。%Objective To analyze and evaluate the blood collection and supply situation from 2008 to 2013of the Center Blood Bank of Yichang so as to guide future work.Methods We referred to the information stored in the computer system of the center blood bank and made a statistical analysis and comparison on the changes of blood collection volumes, scrap rates and supply volumes of various blood components.Results The volumes of blood collection and supply from 2008 to 2013 in the center blood bank were increasing year by year while the scrap rates were decreasing year by year.Conclusion The quality management of the Center Blood Bank of Yichang was continuously improving. It has achieved remarkable results. This data analysis would be helpful for the center blood bank to cope with the rapid development in the next few years.

  11. Early microvascular changes in the preterm neonate: a comparative study of the human and guinea pig.

    Science.gov (United States)

    Dyson, Rebecca M; Palliser, Hannah K; Lakkundi, Anil; de Waal, Koert; Latter, Joanna L; Clifton, Vicki L; Wright, Ian M R

    2014-09-17

    Dysfunction of the transition from fetal to neonatal circulatory systems may be a major contributor to poor outcome following preterm birth. Evidence exists in the human for both a period of low flow between 5 and 11 h and a later period of increased flow, suggesting a hypoperfusion-reperfusion cycle over the first 24 h following birth. Little is known about the regulation of peripheral blood flow during this time. The aim of this study was to conduct a comparative study between the human and guinea pig to characterize peripheral microvascular behavior during circulatory transition. Very preterm (≤28 weeks GA), preterm (29-36 weeks GA), and term (≥37 weeks GA) human neonates underwent laser Doppler analysis of skin microvascular blood flow at 6 and 24 h from birth. Guinea pig neonates were delivered prematurely (62 day GA) or at term (68-71 day GA) and laser Doppler analysis of skin microvascular blood flow was assessed every 2 h from birth. In human preterm neonates, there is a period of high microvascular flow at 24 h after birth. No period of low flow was observed at 6 h. In preterm animals, microvascular flow increased after birth, reaching a peak at 10 h postnatal age. Blood flow then steadily decreased, returning to delivery levels by 24 h. Preterm birth was associated with higher baseline microvascular flow throughout the study period in both human and guinea pig neonates. The findings do not support a hypoperfusion-reperfusion cycle in the microcirculation during circulatory transition. The guinea pig model of preterm birth will allow further investigation of the mechanisms underlying microvascular function and dysfunction during the initial extrauterine period.

  12. Microvascular Abnormality in Schizophrenia as Shown by Retinal Imaging

    Science.gov (United States)

    Meier, Madeline H.; Shalev, Idan; Moffitt, Terrie E.; Kapur, Shitij; Keefe, Richard S.E.; Wong, Tien; Belsky, Daniel W.; Harrington, HonaLee; Hogan, Sean; Houts, Renate; Caspi, Avshalom; Poulton, Richie

    2013-01-01

    Objective Retinal and cerebral microvessels are structurally and functionally homologous, but, unlike cerebral microvessels, retinal microvessels can be noninvasively measured in vivo via retinal imaging. Here we test the hypothesis that individuals with schizophrenia show microvascular abnormality and evaluate the utility of retinal imaging as a tool for future schizophrenia research. Methods Participants were members of the Dunedin Study, a population-representative cohort followed from birth with 95% retention. Study members underwent retinal imaging at age 38 years. We assessed retinal arteriolar and venular caliber for all members of the cohort, including individuals who developed schizophrenia. Results Study members who developed schizophrenia were distinguished by wider retinal venules, suggesting microvascular abnormality reflective of insufficient brain oxygen supply. Analyses that controlled for confounding health conditions suggested that wider retinal venules are not simply an artifact of co-occurring health problems in schizophrenia patients. Wider venules were also associated with a dimensional measure of adult psychosis symptoms and with psychosis symptoms reported in childhood. Conclusions Findings provide initial support for the hypothesis that individuals with schizophrenia show microvascular abnormality. Moreover, results suggest that the same vascular mechanisms underlie subthreshold symptoms and clinical disorder and that these associations may begin early in life. These findings highlight the promise of retinal imaging as a tool for understanding the pathogenesis of schizophrenia. PMID:24030514

  13. Nitrate poisoning in cattle. 4. The effect of nitrite dosing during parturition on the oxygen capacity of maternal blood and the oxygen supply to the unborn calf.

    Science.gov (United States)

    Malestein, A; Geurink, J H; Schuyt, G; Schotman, A J; Kemp, A; van 't Klooster, A T

    1980-07-15

    In a series of experiments the effect of administering KNO2 was studied, during parturition, on the capability of oxygen transport of maternal blood and on oxygen transfer to foetal blood. The following blood parameters were analysed, MHb percentage, pO2, O2-saturation, pH, pCO2, and (NO2) in maternal arterial blood (carotid art.) and venous blood (jugular vein) and in foetal arterial blood (umbilical art.) and venous blood (umbilical vein). The relative O2-saturation was calculated from the estimated O2-saturation by multiplying with the factor Hb (mmol/l) minus MHb (mmol/l), divided by Hb (mmol/l). In addition, blood pressure in the carotid artery, heart rate, and respiration rate in the dam were continuously recorded for some hours. A dosage of 9 to 12 mg of NO1/kg body weight intravenously or of 30 mg of NO2/kg body weight orally to the dam caused much higher MHb percentages and NO2 contents in the maternal blood than in the foetal blood. In maternal blood the ratio of NO2 content to MHb percentage was proportional to that in foetal blood. In the arterial blood, MHb percentages were almost as high as in the venous blood. After administering of nitrite, relative O2-saturation dropped simultaneously with the increase in methaemoglobin. Nitrite treatment caused a drop in the maternal blood pressure; heart rate and respiration rate increased. O2-saturation in the blood in the umbilical vein was much lower in the animals with nitrite treatment than in those without. These experimental results show clearly that the oxygen capacity of the blood decreases after nitrite treatment. In pregnant cows the oxygen supply to the foetus will be adversely affected after nitrate intake, especially by the lower oxygen transfer via the placenta, though hardly at all by methaemoglobin formation in the foetal blood. When the oxygen transfer to the foetal blood decreases too sharply, intra-uterine death and ultimately abortion may result.

  14. Numerical simulation of blood flow and interstitial fluid pressure in solid tumor microcirculation based on tumor-induced angiogenesis

    Science.gov (United States)

    Zhao, Gaiping; Wu, Jie; Xu, Shixiong; Collins, M. W.; Long, Quan; König, Carola S.; Jiang, Yuping; Wang, Jian; Padhani, A. R.

    2007-10-01

    A coupled intravascular transvascular interstitial fluid flow model is developed to study the distributions of blood flow and interstitial fluid pressure in solid tumor microcirculation based on a tumor-induced microvascular network. This is generated from a 2D nine-point discrete mathematical model of tumor angiogenesis and contains two parent vessels. Blood flow through the microvascular network and interstitial fluid flow in tumor tissues are performed by the extended Poiseuille’s law and Darcy’s law, respectively, transvascular flow is described by Starling’s law; effects of the vascular permeability and the interstitial hydraulic conductivity are also considered. The simulation results predict the heterogeneous blood supply, interstitial hypertension and low convection on the inside of the tumor, which are consistent with physiological observed facts. These results may provide beneficial information for anti-angiogenesis treatment of tumor and further clinical research.

  15. Preventing microvascular complications in type 1 diabetes mellitus.

    Science.gov (United States)

    Viswanathan, Vijay

    2015-04-01

    Patients with complications of diabetes such as retinopathy, nephropathy, and cardiovascular complications have increased hospital stay with greater economic burden. Prevention of complications should be started before the onset of type 1 diabetes mellitus (T1DM) by working on risk factors and thereafter by intervention upon confirmatory diagnosis which can prevent further damage to β-cells. The actual risk of getting microvascular complications like microalbuminuria and retinopathy progression starts at glycated hemoglobin (HbA1c) level of 7%. As per the American Diabetes Association, a new pediatric glycemic control target of HbA1c 20 years as compared to patients <10 years of age. Screening of these complications should be done regularly, and appropriate preventive strategies should be followed. Angiotensin converting enzyme inhibitors and angiotensin II receptor blocker reduce progression from microalbuminuria to macroalbuminuria and increase the regression rate to normoalbuminuria. Diabetic microvascular complications can be controlled with tight glycemic therapy, dyslipidemia management and blood pressure control along with renal function monitoring, lifestyle changes, including smoking cessation and low-protein diet. An integrated and personalized care would reduce the risk of development of microvascular complications in T1DM patients. The child with diabetes who receives limited care is more likely to develop long-term complications at an earlier age. Screening for subclinical complications and early interventions with intensive therapy is the need of the hour.

  16. Microvascular Remodeling and Wound Healing: A Role for Pericytes

    Science.gov (United States)

    Dulmovits, Brian M.; Herman, Ira M.

    2012-01-01

    Physiologic wound healing is highly dependent on the coordinated functions of vascular and non-vascular cells. Resolution of tissue injury involves coagulation, inflammation, formation of granulation tissue, remodeling and scarring. Angiogenesis, the growth of microvessels the size of capillaries, is crucial for these processes, delivering blood-borne cells, nutrients and oxygen to actively remodeling areas. Central to angiogenic induction and regulation is microvascular remodeling, which is dependent upon capillary endothelial cell and pericyte interactions. Despite our growing knowledge of pericyte-endothelial cell crosstalk, it is unclear how the interplay among pericytes, inflammatory cells, glia and connective tissue elements shape microvascular injury response. Here, we consider the relationships that pericytes form with the cellular effectors of healing in normal and diabetic environments, including repair following injury and vascular complications of diabetes, such as diabetic macular edema and proliferative diabetic retinopathy. In addition, pericytes and stem cells possessing “pericyte-like” characteristics are gaining considerable attention in experimental and clinical efforts aimed at promoting healing or eradicating ocular vascular proliferative disorders. As the origin, identification and characterization of microvascular pericyte progenitor populations remains somewhat ambiguous, the molecular markers, structural and functional characteristics of pericytes will be briefly reviewed. PMID:22750474

  17. Preventing microvascular complications in type 1 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Vijay Viswanathan

    2015-01-01

    Full Text Available Patients with complications of diabetes such as retinopathy, nephropathy, and cardiovascular complications have increased hospital stay with greater economic burden. Prevention of complications should be started before the onset of type 1 diabetes mellitus (T1DM by working on risk factors and thereafter by intervention upon confirmatory diagnosis which can prevent further damage to β-cells. The actual risk of getting microvascular complications like microalbuminuria and retinopathy progression starts at glycated hemoglobin (HbA1c level of 7%. As per the American Diabetes Association, a new pediatric glycemic control target of HbA1c 20 years as compared to patients <10 years of age. Screening of these complications should be done regularly, and appropriate preventive strategies should be followed. Angiotensin converting enzyme inhibitors and angiotensin II receptor blocker reduce progression from microalbuminuria to macroalbuminuria and increase the regression rate to normoalbuminuria. Diabetic microvascular complications can be controlled with tight glycemic therapy, dyslipidemia management and blood pressure control along with renal function monitoring, lifestyle changes, including smoking cessation and low-protein diet. An integrated and personalized care would reduce the risk of development of microvascular complications in T1DM patients. The child with diabetes who receives limited care is more likely to develop long-term complications at an earlier age. Screening for subclinical complications and early interventions with intensive therapy is the need of the hour.

  18. ACTOVEGIN INFLUENCE ON METABOLIC AND VASOMOTOR FUNCTION OF MICROVASCULAR ENDOTHELIAL OF HUMAN SKIN

    Directory of Open Access Journals (Sweden)

    A. A. Fedorovich

    2010-01-01

    Full Text Available Aim. To evaluate effects of Actovegin (deproteinized hemoderivative on vasomotor and metabolic functions of microvascular skin endothelium in healthy volunteers during acute pharmacological test.Material and methods. 24 healthy male volunteers, aged 18-26 years (21,9±2,7, received Actovegin i.v. during 2 hour infusion through the left cubital vein. Right forearm skin laser Doppler flowmetry (LDF with wavelet analysis of the microcirculatory oscillations was used initially and after 2 hour Actovegin infusion to assess microvascular endothelial responses (microcirculatory blood flow changes to Actovegin. Saline infusion in 5 subjects used for control data receiving.Results. Actovegin significantly increased in maximal amplitude endothelial rhythm (at a frequency of 0.01 Hz by 76% (p<0,001 and functional contribution of microvascular endothelium in the overall level of tissue perfusion by 79% (p<0,001. Control saline infusion resulted in reduction of these indices by 52 and 54%, respectively. Actovegin also increased significantly myogenic rhythm amplitude (vascular tone reduction by 35% (p<0,05 and decreased diastolic blood pressure by 3 mm Hg (p=0,076, which is likely result of increased endothelium nitric oxide release.Conclusion. Microcirculatory oscillations at the frequency of 0.01 Hz reflect both vasomotor and metabolic function of microvascular endothelium. Actovegin improves oxygen and glucose tissue utilization as well as increases nitric oxide production with microvascular smooth muscle tone reduction.

  19. Hemodynamic Consequences of Changes in Microvascular Structure.

    Science.gov (United States)

    Rizzoni, Damiano; Agabiti-Rosei, Claudia; Agabiti-Rosei, Enrico

    2017-10-01

    In hypertension, an increased media-to-lumen ratio of small resistance arteries might play an important role in the increase of vascular resistance, and may also be an adaptive response to the increased hemodynamic load. The presence of morphological alteration in the microvasculature may be associated to an impaired tissue perfusion and/or to the development of target organ damage. Structural alterations in the microcirculation might represent a predictor of the onset of cardio-cerebrovascular events and hypertension complications. A cross-talk between the small and large artery may exaggerate arterial damage, following a vicious circle. Therefore, in the present review, possible hemodynamic consequences of the presence of microvascular structural alterations will be considered, in terms of their time of onset, role in the development and/or maintenance of high blood pressure values, and interrelationships with structural/mechanical alterations of large conductance arteries. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. [Microvascular anastomoses in cervical esophageal reconstruction].

    Science.gov (United States)

    Takushima, A; Harii, K; Asato, H

    2001-09-01

    Ischemia or hemostasis in the gastric, jejunal, and colonic pedicle after esophagectomy is believed to contribute significantly to postoperative complications. With the advent of microvascular anastomoses, many surgeons have adopted vascular augmentation (supercharge) as a means of avoiding these difficulties. Microsurgical free tissue transfer represented by the free jejunum and forearm flap also plays an important role in esophageal reconstruction. In this paper, the authors introduce the technical points important for successful revascularization including the choice of recipient vessels, setting up of the reconstructive materials, and postoperative monitoring. In cases of gastric pull-up elevated via posterior mediastinum, the left gastroduodenal vessels are anastomosed to the cervical transverse or superior thyroidal vessels. In cases of duodenal or colonic pull-up elevated via the anterosternal route, the vascular pedicles are anastomosed to the internal mammary vessels which are dissected by resecting the costal cartilage. When the free jejunum flap is used, the cervical transverse or superior thyroidal vessels are most frequently used as recipients. Postoperative monitoring of free flaps is performed using Doppler ultrasound or through a small skin incision made above the transferred tissue. Although gastric or colonic pull-up is difficult to monitor, color Doppler sonography permits quantitative analysis of blood flow and may be a useful option.

  1. Coronary microvascular dysfunction: an update

    Science.gov (United States)

    Crea, Filippo; Camici, Paolo G.; Bairey Merz, Cathleen Noel

    2014-01-01

    Many patients undergoing coronary angiography because of chest pain syndromes, believed to be indicative of obstructive atherosclerosis of the epicardial coronary arteries, are found to have normal angiograms. In the past two decades, a number of studies have reported that abnormalities in the function and structure of the coronary microcirculation may occur in patients without obstructive atherosclerosis, but with risk factors or with myocardial diseases as well as in patients with obstructive atherosclerosis; furthermore, coronary microvascular dysfunction (CMD) can be iatrogenic. In some instances, CMD represents an epiphenomenon, whereas in others it is an important marker of risk or may even contribute to the pathogenesis of cardiovascular and myocardial diseases, thus becoming a therapeutic target. This review article provides an update on the clinical relevance of CMD in different clinical settings and also the implications for therapy. PMID:24366916

  2. Intravascular Stenting in Microvascular Anastomoses

    DEFF Research Database (Denmark)

    Assersen, Kristine; Sørensen, Jens

    2015-01-01

    Background The effect of intravascular stenting (IVaS) on microvascular anastomoses has given adverse results. For experienced microsurgeons the benefit of IVaS is doubtful. We have investigated the potential benefit of the IVaS technique for two groups of inexperienced microsurgeons with different...... surgical levels of experience (medical students and young residents). Experienced microsurgeons acted as a control group. Materials and Methods In an experimental crossover study, 139 microsurgical anastomoses were performed on the femoral artery in 70 rats by 10 surgeons. On one side of the rat, the IVaS...... spent on the anastomosis. Results No significant difference in patency rates was seen between the stenting and conventional technique in all three groups. The experienced microsurgeons had 100% patency rate with both techniques. The medical students had 20/28 in the IVaS and 19/28 conventional group...

  3. The role of the microvascular tortuosity in tumor transport phenomena.

    Science.gov (United States)

    Penta, R; Ambrosi, D

    2015-01-07

    The role of the microvascular network geometry in transport phenomena in solid tumors and its interplay with the leakage and pressure drop across the vessels is qualitatively and quantitatively discussed. Our starting point is a multiscale homogenization, suggested by the sharp length scale separation that exists between the characteristic vessels and the tumor tissue spatial scales, referred to as the microscale and the macroscale, respectively. The coupling between interstitial and capillary compartment is described by a double Darcy model on the macroscale, whereas the geometric information on the microvascular structure is encoded in the effective hydraulic conductivities, which are numerically computed by solving classical differential problems on the microscale representative cell. Then, microscale information is injected into the macroscopic model, which is analytically solved in a prototypical geometry and compared with previous experimentally validated, phenomenological models. In this way, we are able to capture the role of the standard blood flow determinants in the tumor, such as tumor radius, tissue hydraulic conductivity and vessels permeability, as well as influence of the vascular tortuosity on fluid convection. The results quantitatively confirm that transport of blood (and, as a consequence, of any advected anti-cancer drug) can be dramatically impaired by increasing the geometrical complexity of the microvasculature. Hence, our quantitative analysis supports the argument that geometric regularization of the capillary network improves blood transport and drug delivery in the tumor mass.

  4. Microvascular hemodynamics in human hypothermic circulatory arrest and selective antegrade cerebral perfusion

    NARCIS (Netherlands)

    P.W.G. Elbers; A. Ozdemir; R.H. Heijmen; J. Heeren; M. van Iterson; E.P.A. van Dongen; C. Ince

    2010-01-01

    Objective: The behavior of the human microcirculation in the setting of cardiac arrest is largely unknown. Animal experiments have consistently revealed that global hemodynamics do not necessarily reflect microvascular perfusion. In addition, the time it takes for capillary blood flow to stop after

  5. Coronary microvascular dysfunction in overt diabetic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    K. Bratis

    2014-11-01

    Conclusion: In patients with DM2 myocardial perfusion reserve is markedly decreased, suggestive of microvascular disease. In this small cohort MPRI impairment did not correlate to the LV EF deterioration.

  6. 2型糖尿病合并阻塞性睡眠呼吸暂停低通气综合征患者夜间血糖波动增加微血管并发症的风险%Nocturnal blood glucose fluctuation of type 2 diabetes mellitus complicated with obstructive sleep apnea hypopnea syndrome increases the risk of microvascular complications

    Institute of Scientific and Technical Information of China (English)

    李晨光; 倪长霖; 常宝成; 杨敏; 汤云昭; 朱艳娟; 李竹; 姜振环; 于萍

    2015-01-01

    Objective To investigate the association between blood glucose fluctuation and microvascular complications in type 2 diabetes mellitus patients complicated with obstructive sleep apnea hypopnea syndrome(OSAHS). Methods 55 patients(34 males and 21 females,with an average of (61 ± 6) years old) complicated with OSAHS were enrolled as case group,and 55 patients (30 males and 25 females, with an average of (60±5)years old) without OSAHS were enrolled as control group.Blood glucose, blood lipid, glycosylated hemoglobin A1c (HbA1c),and 24 h urinary microalbumin (24 hUMA) was detected. Dynamic glucose monitoring system(CGMS) was used to monitor the values of mean amplitude of glycemic excursions (MAGE),standard deviation of blood glucose (SDBG), mean of daily differences (MODD),largest amplitude of glycemic excursions (LAGE),the low blood glucose time percentage(7.8 mmol/L), high blood glucose time percentage(>11.1 mmol/L) and blood glucose fluctuation coefficient.Apnea hypopnea index (AHI) was monitored by polysomnography (PSG), microvascular complications of all patients were also detected.t test,χ2 test,variance analysis, Pearson product moment correlation analysis and Logistic multivariate analysis were used to evaluate the data. Results (1)The values of MAGE,SDBG, MODD,LAGE,low blood glucose time percentage(7.8 mmol/L)、高血糖时间百分比(>11.1 mmol/L)及血糖波动系数,采用多导睡眠图(PSG)监测睡眠呼吸暂停指数(AHI),并检测患者微血管并发症发生情况.采用t检验、?2检验、方差分析、Pearson积矩相关分析、Logistic多因素分析进行数据统计. 结果 (1)随着AHI的增加,其MAGE、SDBG、MODD、LAGE、低血糖时间百分比(<3.9 mmol/L)及血糖波动系数也随之增加(F=28.137、26.226、19.802、17.734、29.132、29.404,均P<0.05).(2)AHI与MAGE、SDBG及血糖波动系数呈正相关(r=0.465、0.696、0.533,均P<0.05).(3)病例组的微血管并发症发生率明显高于对

  7. Microvascular flow estimation by microbubble-assisted Nakagami imaging.

    Science.gov (United States)

    Tsui, Po-Hsiang; Yeh, Chih-Kuang; Chang, Chien-Cheng

    2009-04-01

    The destruction and replenishment of microbubbles has been previously applied to estimating blood flow in the microcirculation. The rate of increase of the time-intensity curve (TIC) due to microbubbles flowing into the region-of-interest (ROI) as measured from the conventional B-mode images reflects the flow velocity. In this study, we monitored microbubble replenishment using a new proposed approach called the time-Nakagami-parameter curve (TNC) obtained from the parametric image based on the Nakagami statistical parameter for quantifying the microvascular flow velocity. The Nakagami parameter is estimated from signal envelope to reflect the backscattered statistics. The feasibility of using the TNC to estimate the microvascular flow was explored by carrying out phantom measurements and in vivo animal experiments. The rates of increase of the TIC and TNC were quantified as the rate constants beta(I) and beta(N) of monoexponential fitted curves, respectively. The experimental results showed that beta(N) behaves similarly to the conventional beta(I) in quantifying the flow velocity. Moreover, the tolerance to the effects of clutter is greater for the TNC than for the TIC, which makes it possible to use beta(N) to differentiate various flow velocities even when the ROI contains nonperfused areas. This finding suggests that the TNC-based technique can be used as a complementary tool for the conventional TIC to improve measurement of blood flow in the microcirculation.

  8. Monitoring microvascular free flaps with tissue oxygen measurement and PET.

    Science.gov (United States)

    Schrey, Aleksi R; Kinnunen, Ilpo A J; Grénman, Reidar A; Minn, Heikki R I; Aitasalo, Kalle M J

    2008-07-01

    Tissue oxygen measurement and positron emission tomography (PET) were evaluated as methods for predicting ischemia in microvascular free flaps of the head and neck. Ten patients with head and neck squamous cell cancer underwent resection of the tumour followed by microvascular reconstruction with a free flap. Tissue oxygenation of the flap (P(ti)O(2)) was continuously monitored for three postoperative (POP) days and the blood flow of the flap was assessed using oxygen-15 labelled water and PET. In three free flaps a perfusion problem was suspected due to a remarkable drop in P(ti)O(2)-values, due to two anastomosis problems and due to POP turgor. No flap losses occurred. During the blood flow measurements with PET [mean 8.5 mL 100 g(-1) min(-1 )(SD 2.5)], the mean P(ti)O(2) of the flaps [46.8 mmHg (SD 17.0)] appeared to correlate with each other in each patient (pmonitoring system of free flaps. The perfusion-study with PET correlates with P(ti)O(2)-measurement.

  9. The association of systemic microvascular changes with lung function and lung density: a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Bianca Harris

    Full Text Available Smoking causes endothelial dysfunction and systemic microvascular disease with resultant end-organ damage in the kidneys, eyes and heart. Little is known about microvascular changes in smoking-related lung disease. We tested if microvascular changes in the retina, kidneys and heart were associated with obstructive spirometry and low lung density on computed tomography. The Multi-Ethnic Study of Atherosclerosis recruited participants age 45-84 years without clinical cardiovascular disease. Measures of microvascular function included retinal arteriolar and venular caliber, urine albumin-to-creatinine ratio and, in a subset, myocardial blood flow on magnetic resonance imaging. Spirometry was measured following ATS/ERS guidelines. Low attenuation areas (LAA were measured on lung fields of cardiac computed tomograms. Regression models adjusted for pulmonary and cardiac risk factors, medications and body size. Among 3,397 participants, retinal venular caliber was inversely associated with forced expiratory volume in one second (FEV(1 (P<0.001 and FEV(1/forced vital capacity (FVC ratio (P = 0.04. Albumin-to-creatinine ratio was inversely associated with FEV(1 (P = 0.002 but not FEV(1/FVC. Myocardial blood flow (n = 126 was associated with lower FEV(1 (P = 0.02, lower FEV(1/FVC (P = 0.001 and greater percentage LAA (P = 0.04. Associations were of greater magnitude among smokers. Low lung function was associated with microvascular changes in the retina, kidneys and heart, and low lung density was associated with impaired myocardial microvascular perfusion. These cross-sectional results suggest that microvascular damage with end-organ dysfunction in all circulations may pertain to the lung, that lung dysfunction may contribute to systemic microvascular disease, or that there may be a shared predisposition.

  10. Head Loss As an Explanation of the Steal Phenomenon in Microvascular Surgery

    OpenAIRE

    Ross, Phillip E.; Deleyiannis, Frederic W.-B.

    2015-01-01

    Vascular steal has been cited to help explain end-organ ischemia after microvascular reconstruction. Attempts to clarify a mechanism of vascular steal have been made by modeling blood circulation after a simple electrical circuit, suggesting that the free flap provides a path of least resistance for blood flow and thereby compromises end-organ perfusion. We present a case of a posterior medial thigh perforator flap for the reconstruction of a diabetic foot ulcer in a patient with a single ves...

  11. Revascularization and tissue regeneration of an empty root canal space is enhanced by a direct blood supply and stem cells.

    Science.gov (United States)

    Srisuwan, Tanida; Tilkorn, Daniel J; Al-Benna, Sammy; Abberton, Keren; Messer, Harold H; Thompson, Erik W

    2013-04-01

    Regenerative endodontics is an innovative treatment concept aiming to regenerate pulp, dentin and root structures. In the diseased or necrotic tooth, the limitation in vascular supply renders successful tissue regeneration/generation in a whole tooth challenging. The aim of this study is to evaluate the ability of vascularized tissue to develop within a pulpless tooth using tissue engineering techniques. A pulpless tooth chamber, filled with collagen I gel containing isolated rat dental pulp cells (DPC) and angiogenic growth factors, was placed into a hole created in the femoral cortex or into its own tooth socket, respectively. The gross, histological and biochemical characteristics of the de novo tissue were evaluated at 4 and 8 weeks post-transplantation. Tooth revascularization and tissue generation was observed only in the femur group, confirming the important role of vascular supply in tissue regeneration. The addition of cells and growth factors significantly promoted connective tissue production in the tooth chamber. Successful revascularization and tissue regeneration in this model demonstrate the importance of a direct vascular supply and the advantages of a stem cell approach. © 2012 John Wiley & Sons A/S.

  12. Visible light optical coherence tomography for microvascular oximetry in ocular circulation (Conference Presentation)

    Science.gov (United States)

    Chen, Siyu; Yi, Ji; Zhang, Hao F.

    2016-03-01

    Visible light optical coherence tomography (vis-OCT) is intrinsically capable of optical determination of blood oxygen saturation (sO2). Thanks to its 3D sectioning ability, confounding factors that plaque multi-wavelength fundus photography can be avoided. We further supplemented it with motion-enhanced angiography (vis-OCTA), which allowed us to resolve retinal micro vessels without losing spectral information. As a result, spectroscopic vis-OCTA can extract microvascular sO2 which are generally inaccessible. Here we extend the theoretical formulation of vis-OCTA oximetry to include optical attenuation, scattering and motion contrast. The model allows robust estimation of sO2, while also promising reduction of illuminating power to 1/3 of current value of ~1 mW. To demonstrate the capability of our approach, we performed oxygen challenge while taking vis-OCTA measurements on rat ocular circulation in vivo. We supplied the experiment animal with the following gas mixture: normal air, 5% CO2 air, pure O2 and 10% O2 air. For each inhalation gas, the OCTA measurements were compared with peripheral capillary sO2 (spO2) provided by a pulse oximeter. The retinal artery sO2 measurements corresponded well with spO2 reading as expected (R2 = 0.87). We found that both retinal and choroidal circulation sO2 moderately increased when we supplied 5% CO2 air. 100% O2 inhalation significantly increased both artery and vein oxygenation. On the contrary, 10% O2 air could deplete the oxygen reservoir in the circulation and lead to low sO2 readings.

  13. Suggestions on Blood Collection and Supply Station for Sustainable Development%促进采供血机构持续发展的相关建议

    Institute of Scientific and Technical Information of China (English)

    王兆福; 温涛

    2012-01-01

    Analysis on the existing problem of blood collection and supply station in Henan Province and combine with work practices to put forward five suggestions;to adopt government to push forward mode, to urge volunteer giving blood to keep on a development;to increase personnel and fund, raise to collect blood service quality;to reasonable program the concentration examine laboratory;to aggressive adopt forerunner examines means and ensure clinical use blood safety;to improve quality manages system,etc.%对河南省采供血机构存在问题进行了分析.结合工作实践提出了5点建议:采取政府推进模式,促无偿献血持续发展;增加人员编制和投入,提高采血服务质量;合理规划集中检测实验室;积极采用先进检测手段,确保临床用血安全;完善质量管理体系等.

  14. Study of microvascular structure in keloid and hypertrophic scars: density of microvessels and the efficacy of three-dimensional vascular imaging.

    Science.gov (United States)

    Kurokawa, Norifumi; Ueda, Koichi; Tsuji, Motomu

    2010-12-01

    We have investigated the blood vessels in keloids and hypertrophic scars, both morphologically and statistically. We also tried to construct three-dimensional images of blood vessels in a keloid and hypertrophic scar to clarify the vascular patterns. Keloids (n = 16) and hypertrophic scars (n = 12) were stained with haematoxylin and eosin, and immunostained with anti-CD31 antibody. The capillary density (number/1.0 mm(2)) and length of the major and minor axes were measured, and the major:minor axis ratio was calculated. Eighty serial sections were prepared from the preparations. Using image preparation software (Realia, INTAGE), the 80 input images were superimposed to construct a three-dimensional image of blood vessels in the tissue. We initially succeeded in constructing three-dimensional images of blood vessels in a keloid and hypertrophic scar. By statistical analysis of the vascular density and morphology, we clarified that there were fewer capillaries in keloids than in hypertrophic scars (p < 0.01), and that the vascular lumen was flattened. Capillaries in the central region of keloids tended to flat, compared with those in the marginal region. Three-dimensional images suggested that there was no microvascular communication in keloids; there was also an inadequate blood supply in keloid tissue. These findings may be a result of the growth of collagen and fibroblasts with keloid maturation.

  15. 神经性失语的血液供应特点分析%Analysis of blood supply in aphasia

    Institute of Scientific and Technical Information of China (English)

    王洪典; 江文; 万琪; 张光运

    2001-01-01

    Objective To study the characteristics of blood supply in neurlogical aphasia.Method The aphasia types and features of 21 cases with internal carotid artery occulsion or middle cerebral artery occulision were retrospectively reviewed .Result The ischaemic lesions in most of patients with aphasia located in dominant hemisphere,but the cases with the same artery occlusion exhibited different aphasia types.Broca's aphasia was usually accompanied with good prognosis,but it is diffcult to rehabilitate for Wernicke's aphasia and Global aphasis .Conclusion The aphasia types were associated with complicated blood supply and collateral circulation in MARE'S area.%目的 讨神经性失语的血液供应特点。方法回顾性分析21例颈内动脉或大脑中动脉闭塞病人的失语种类及特征。结果 部分失语病人的缺血病灶位于优势半球,但具有相同动脉闭塞病人的失语类型并不相同。单纯运动性失语康复较快,混合性或感觉性失语康复较困难。结论 语的类型因MARE方形区复杂血供及其侧支循环情况的不同而异。

  16. 神经性失语的血液供应特点分析%Analysis of blood supply in aphasia

    Institute of Scientific and Technical Information of China (English)

    王洪典; 江文; 万琪; 张光运

    2001-01-01

    Objective To study the characteristics of blood supply inneurlogical aphasia.Method The aphasia types and features of 21 cases with internal carotid artery occulsion or middle cerebral artery occulision were retrospectively reviewed .Result The ischaemic lesions in most of patients with aphasia located in dominant hemisphere,but the cases with the same artery occlusion exhibited different aphasia types.Broca's aphasia was usually accompanied with good prognosis,but it is diffcult to rehabilitate for Wernicke's aphasia and Global aphasis .Conclusion The aphasia types were associated with complicated blood supply and collateral circulation in MARE'S area.%目的 探讨神经性失语的血液供应特点。方法回顾性分析21例颈内动脉或大脑中动脉闭塞病人的失语种类及特征。结果 部分失语病人的缺血病灶位于优势半球,但具有相同动脉闭塞病人的失语类型并不相同。单纯运动性失语康复较快,混合性或感觉性失语康复较困难。结论 语的类型因MARE方形区复杂血供及其侧支循环情况的不同而异。

  17. [Recent circumstances in the supply and demand of various blood products in Japan, and appropriate use of blood components or plasma protein derivatives].

    Science.gov (United States)

    Tohyama, H

    1986-10-01

    In Japan, as in the United States and several other advanced countries, the use of fresh frozen plasma (FFP) and albumin has increased dramatically over the past 10 years. Especially in Japan the increase has been at least tenfold, and half of this usage has been for surgery. Most reviews of albumin usage acknowledge that there is a high ratio of wastage, or use in clinical circumstances without a firm scientific basis. Recently Japan has imported an enormous volume of various plasma fraction products such as albumin, Factor VIII etc., or plasma as raw material from foreign countries, especially the United States. As a result, Japan has come to monopolized a quarter of the albumin manufactured in the world, and has therefore received much internal and external criticism from or ethical standpoint. As countermeasures against shortage of these blood products, it will be necessary for doctors to use these blood products more sparingly and to increase the yield of volunteer donor's blood, especially plasma. More red blood cell concentrate should be utilized for hemorrhage in routine surgical operations. Because whole blood transfusion is rarely used except in cases of massive bleeding that cannot be stopped immediately, exchange transfusion has been performed in the United States and European countries recently. Transfusion of FFP is appropriately used only for replacement of coagulation factor deficiencies, massive transfusion etc. in the United States. It should be particularly noted that these carry the risk of transmission of diseases such as hepatitis and possibly AIDS. Albumin is an effective oncotic agent in the treatment of acute shock and in the maintenance of intravascular volume and cardiac output. However, albumin and FFP have no demonstrable effect in the general supportive management of chronic hypoproteinemia and undernutrition.

  18. Threshold of microvascular occlusion: injury size defines the thrombosis scenario

    CERN Document Server

    Belyaev, Aleksey V; Ataullakhanov, Fazly I

    2014-01-01

    Damage to the blood vessel triggers a cascade of processes leading to the formation of a thrombus, which is meant to prevent bleeding. However, the same phenomenon may result in a total blockade of a blood vessel, causing severe medical conditions. Here we develop a mathematical model of thrombus growth in a microvessel, which demonstrates that the size of vascular injury acts like a switch between the regimes of thrombus growth. When the length of injury exceeds the critical value, thrombus occludes the vessel, otherwise the growth stops due to hydrodynamic shear forces. Our findings explain an experimentally observed distinctions between thrombosis induced by chemical lesion and laser injury. We suggest that the specifics of platelet adhesion in combination with microvascular hydrodynamics can be a major reason for cessation of thrombus growth in vivo.

  19. Diabetic microvascular complications: possible targets for improved macrovascular outcomes

    Science.gov (United States)

    D’Elia, John A; Bayliss, George; Roshan, Bijan; Maski, Manish; Gleason, Ray E; Weinrauch, Larry A

    2011-01-01

    The results of recent outcome trials challenge hypotheses that tight control of both glycohemoglobin and blood pressure diminishes macrovascular events and survival among type 2 diabetic patients. Relevant questions exist regarding the adequacy of glycohemoglobin alone as a measure of diabetes control. Are we ignoring mechanisms of vasculotoxicity (profibrosis, altered angiogenesis, hypertrophy, hyperplasia, and endothelial injury) inherent in current antihyperglycemic medications? Is the polypharmacy for lowering cholesterol, triglyceride, glucose, and systolic blood pressure producing drug interactions that are too complex to be clinically identified? We review angiotensin–aldosterone mechanisms of tissue injury that magnify microvascular damage caused by hyperglycemia and hypertension. Many studies describe interruption of these mechanisms, without hemodynamic consequence, in the preservation of function in type 1 diabetes. Possible interactions between the renin–angiotensin–aldosterone system and physiologic glycemic control (through pulsatile insulin release) suggest opportunities for further clinical investigation. PMID:21694944

  20. Microvascular Disease and Ischemic Heart Disease%微血管病变与缺血性心脏病

    Institute of Scientific and Technical Information of China (English)

    田骆冰; 夏岳; 刘超; 刘坤申

    2009-01-01

    冠状动脉微血管在心肌的血供中起着重要作用,冠状动脉微循环对冠心病的发生、发展、疗效及预后具有重要影响而备受人们重视.目前冠状动脉微血管病变主要分为X综合征和冠脉内慢血流现象,二者都与缺血性心脏病存在着密切的关系,但发病机制有所不同.X综合征主要是冠状动脉微血管痉挛所致,而冠脉内慢血流现象传统上被认为与微血管功能失调有关.此外慢血流现象可能是缺血性心脏病的一种新的发病机制,它可能代表了动脉粥样硬化和内皮功能失调的早期阶段.并且二者在治疗上有所不同.%Small coronary arteries play an important role in the blood supply of the myocardial tissues. Microcirculation has an important effect on the pathogenesis, development, therapy, and prognosis of coronary artery disease. At present, coronary microvascular disease mainly includes syndrome X and coronary slow flow phenomenon, which is closely related to ischemic heart disease. However, their pathogenesis differs;syndrome X is caused by a spasm of the microvessels, while coronary slow flow phenomenon is related to a microvascular disfunction. Coronary slow flow phenomenon may be a new pathogenic mechanism for ischemic heart disease.

  1. Blood

    Science.gov (United States)

    ... Also, blood is either Rh-positive or Rh-negative. So if you have type A blood, it's either A positive or A negative. Which type you are is important if you need a blood transfusion. And your Rh factor could be important ...

  2. Skeletal muscle microvascular function in girls with Turner syndrome

    Science.gov (United States)

    West, Sarah L.; O'Gorman, Clodagh S.; Elzibak, Alyaa H.; Caterini, Jessica; Noseworthy, Michael D.; Rayner, Tammy; Hamilton, Jill; Wells, Greg D.

    2014-01-01

    Background Exercise intolerance is prevalent in individuals with Turner Syndrome (TS). We recently demonstrated that girls with TS have normal aerobic but altered skeletal muscle anaerobic metabolism compared to healthy controls (HC). The purpose of this study was to compare peripheral skeletal muscle microvascular function in girls with TS to HC after exercise. We hypothesized that girls with TS would have similar muscle blood-oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) signal responses during recovery from exercise compared to HC. Methods Thirteen TS participants and 8 HC completed testing. BOLD MRI was used to measure skeletal muscle microvascular response during 60 second recovery, following 60 s of exercise at 65% of maximal workload. Exercise and recovery were repeated four times, and the BOLD signal time course was fit to a four-parameter sigmoid function. Results Participants were 13.7 ± 3.1 years old and weighed 47.9 ± 14.6 kg. The mean change in BOLD signal intensity following exercise at the end of recovery, the mean response time of the function/the washout of deoxyhemoglobin, and the mean half-time of recovery were similar between the TS and HC groups. Conclusions Our results demonstrate that compared to HC, peripheral skeletal muscle microvascular function following exercise in girls with TS is not impaired. General significance This study supports the idea that the aerobic energy pathway is not impaired in children with TS in response to submaximal exercise. Other mechanisms are likely responsible for exercise intolerance in TS; this needs to be further investigated. PMID:26676172

  3. Anatomy and histophysiology of the periosteum: quantification of the periosteal blood supply to the adjacent bone with 85Sr and gamma spectrometry.

    Science.gov (United States)

    Chanavaz, M

    1995-01-01

    The periosteum or periosteal membrane is a continuous composite fibroelastic covering membrane of the bone to which it is intimately linked. Although the bone cortex is the main beneficiary of the principal anatomical and physiological functions of the periosteal membrane, the behavior of the entire bone remains closely influenced by periosteal activity. These principal functions are related to the cortical blood supply, osteogenesis, and muscle and ligament attachments. Through its elastic and contractile nature, it participates in the maintenance of bone shape, and plays an important role in metabolic ionic exchange and physiologic distribution of electro-chemical potential differences across its membranous structure. It has also been suggested that the periosteum may have its own specific proprioceptive property. This paper presents a study of the anatomy and histophysiology of the periosteum, and discusses in detail its main functions of cortical blood supply and osteogenesis. It also presents the third intermediary report on a current study of the quantification of cortical vascularization of femoral bone via the periosteum, using an isotonic salt solution containing 85 Strontium. The afferent-efferent (arterio-venous) flows of this solution in the thigh vascular system of guinea pigs were measured by gamma spectrometry after a series of selective macro- and micro-injections of radioactive salt into the femoral arterial system was carried out. Each vascular territory was meticulously selected and the injections were made according to size, starting with the larger vessels, with or without ligatures of neighboring vessels, going progressively to smaller and smaller vessels with diameters not exceeding 100 microns. The principal technical difficulty at this stage of experimentation was related to the identifying and acquiring of appropriate microcatheters. The study also includes a series of measurements after blockage of the transmuscular blood flow and the

  4. Coronary microvascular obstruction in acute myocardial infarction.

    Science.gov (United States)

    Niccoli, Giampaolo; Scalone, Giancarla; Lerman, Amir; Crea, Filippo

    2016-04-01

    The success of a primary percutaneous intervention (PCI) in the setting of ST elevation myocardial infarction depends on the functional and structural integrity of coronary microcirculation. Coronary microvascular dysfunction and obstruction (CMVO) occurs in up to half of patients submitted to apparently successful primary PCI and is associated to a much worse outcome. The current review summarizes the complex mechanisms responsible for CMVO, including pre-existing coronary microvascular dysfunction, and highlights the current limitations in the assessment of microvascular function. More importantly, at the light of the substantial failure of trials hitherto published on the treatment of CMVO, this review proposes a novel integrated therapeutic approach, which should overcome the limitations of previous studies.

  5. Microvascular dysfunction: an emerging pathway in the pathogenesis of obesity-related insulin resistance.

    Science.gov (United States)

    Muris, Dennis M J; Houben, Alfons J H M; Schram, Miranda T; Stehouwer, Coen D A

    2013-03-01

    The prevalence of type 2 diabetes mellitus (T2DM) and its major risk factor, obesity, has reached epidemic proportions in Western society. How obesity leads to insulin resistance and subsequent T2DM is incompletely understood. It has been established that insulin can redirect blood flow in skeletal muscle from non-nutritive to nutritive capillary networks, without increasing total blood flow. This results in a net increase of the overall number of perfused nutritive capillary networks and thereby increases insulin-mediated glucose uptake by skeletal muscle. This process, referred to as functional (nutritive) capillary recruitment, has been shown to be endothelium-dependent and to require activation of the phosphatidylinositol-kinase (PI3K) pathway in the endothelial cell. Several studies have demonstrated that these processes are impaired in states of microvascular dysfunction. In obesity, changes in several adipokines are likely candidates to influence insulin signaling pathways in endothelial cells, thereby causing microvascular dysfunction. Microvascular dysfunction, in turn, impairs the timely access of glucose and insulin to their target tissues, and may therefore be an additional cause of insulin resistance. Thus, microvascular dysfunction may be a key feature in the development of obesity-related insulin resistance. In the present review, we will discuss the evidence for this emerging role for the microcirculation as a possible link between obesity and insulin resistance.

  6. Demonstration of actin filament stress fibers in microvascular endothelial cells in situ.

    Science.gov (United States)

    Nehls, V; Drenckhahn, D

    1991-07-01

    We have developed a method for immunostaining the microvascular tree of rat mesenteric windows in situ. The procedure consists of three steps, i.e., mild fixation with formaldehyde, controlled proteolytic digestion of the mesothelial layer, and permeabilization with acetone. Discrimination between different microvascular segments was possible by double-fluorescent staining with antibodies to the smooth muscle isoform of alpha-actin and to nonmuscle myosin from platelets. Antibodies to nonmuscle myosin labeled numerous longitudinally oriented cables in endothelial cells of all microvascular segments (arterioles, metarterioles, pre-, mid-, and postcapillaries, small venules). Occasionally, the myosin-containing cables displayed the interrupted sarcomere-like staining pattern that is diagnostic for stress fibers. In contrast, staining of actin filaments with phalloidin-rhodamin resulted in a noninterrupted, continuous fluorescence of the stress fibers. A possible functional role of microvascular endothelial stress fibers is to serve as a tensile cytoskeletal scaffold that stabilizes the tubular, three-dimensional geometry of microvessels and, in addition, to help the endothelium resist the shear forces created by blood flow and by collision with red and white blood cells.

  7. Applied anatomical study of the vascularized ulnar nerve and its blood supply for cubital tunnel syndrome at the elbow region

    OpenAIRE

    2015-01-01

    Cubital tunnel syndrome is often accompanied by paresthesia in ulnar nerve sites and hand muscle atrophy. When muscle weakness occurs, or after failure of more conservative treatments, anterior transposition is used. In the present study, the ulnar nerve and its blood vessels were examined in the elbows of 18 adult cadavers, and the external diameter of the nutrient vessels of the ulnar nerve at the point of origin, the distances between the origin of the vessels and the medial epicondyle of ...

  8. Microvascular angina in postmenopausal women.

    Directory of Open Access Journals (Sweden)

    Alexander Valdés Martín

    2011-10-01

    Full Text Available Fundamento: la angina microvascular es frecuente en mujeres posmenopáusicas. La isquemia miocárdica ha sido inducida mediante pruebas de estrés, en las que se ha comprobado una relación entre la disfunción endotelial y los defectos de perfusión miocárdica. Objetivo: determinar si la isquemia miocárdica puede evidenciarse por anormalidades de la perfusión y de la función detectadas por gammagrafía miocárdica en mujeres con angina típica, angiografía coronaria normal y disfunción endotelial. Métodos: estudio descriptivo realizado en el Instituto de Cardiología y Cirugía Cardiovascular de La Habana que incluyó 59 mujeres. Se les realizó lipidograma, se les midió función endotelial de la arteria braquial mediante ultrasonido, y estudio electrocardiográfico de 24 horas (Holter. Se aplicó un protocolo de estrés-reposo durante la gammagrafía. Las pacientes fueron divididas en dos grupos, acorde a la presencia (grupo I o ausencia (grupo II de defectos de perfusión miocárdica. Resultados: mostraron defectos de la perfusión 21 pacientes. El 57 % de las pacientes del grupo I exhibió más disfunción endotelial. Sólo doce pacientes mostraron defectos reversibles de la perfusión y en el 75 % de los casos se asoció a una reducción de la fracción de eyección ventricular izquierda postestrés mayor de un 5 % y a anormalidades regionales de la motilidad de la pared. Tres pacientes en el grupo I mostraron evidencia de isquemia comparado con cuatro en el grupo II. Conclusiones: la isquemia inducida por estrés se asocia a una reducción de la fracción de eyección ventricular izquierda postestrés y a una vasodilatación anormal dependiente del endotelio.

  9. 冈上肌腱的血供特点及临床意义%Blood supply of the supraspinatus and its clinical significance

    Institute of Scientific and Technical Information of China (English)

    许本柯; 杨运平; 刘洪涛; 罗钢; 刘兵; 刘本菊

    2012-01-01

    Objective To provide anatomic basis of blood supply for preventing and treating of shoulder joint disease and reconstructing of shoulder joint function. Methods 40 specimens of adult upper limbs fixed and perfused with red emulsion were used. Supraspinatus was dissected for exploring its anatomic features. Results The blood supply of supraspinatus was mainly from the suprascapular artery and the descending branch of transverse cervical artery. The outer diameter at the beginning was (2.9±0.3) mm, and the length of main trunk was (4.8 ±0.7) cm. The muscular branches supplying supraspinatus divided into two to three branches to enter the muscle belly above or below the scapula ligamentum transversum. The place of the branches entering the muscle belly located at the point (1.9±0.2) mm antero-inferior to the scapula ligamentum transversum. The arterial anastomosis of tendon of supraspinatus was affluent at the transmigration part and expansion part. While the capillary was rare at the place 1 cm distal to the insertion of tendon in the parenchyma part, which was a apparent area lacking of blood vessels. The supraspinatus was mainly innervated by suprascapular nerve, which divided into two to three branches accompanied by blood vessels to innervate supraspinatus. Conclusions On repairing of the rotator cuff tear or injury, it is unsuitable to simply sew the broken end. The broken end sew should be performed after cutting the ischemic tissue or transferring suitable tendon medium, for improving the regional blood supply, which is helpful for healing.%目的 为肩关节疾患的防治及肩关节功能的重建提供血供解剖学基础.方法 采用40侧常规防腐灌注红色乳胶的成人上肢标本,解剖出冈上肌观察其形态结构、起止点、血供来源、走行、分布特点并测量有关数据.结果 冈上肌的血供主要来自肩胛上动脉和颈横动脉降支.肩胛上动脉起始处外径为(2.9±0.3) mm,主干长(4.8±0.7)cm;营养

  10. Bosentan fosters microvascular de-remodelling in systemic sclerosis.

    Science.gov (United States)

    Guiducci, S; Bellando Randone, S; Bruni, C; Carnesecchi, G; Maresta, A; Iannone, F; Lapadula, G; Matucci Cerinic, M

    2012-12-01

    Bosentan, a dual endothelin receptor antagonist, may reduce blood pressure by blocking the vasoconstrictor effect of endothelin-1. In systemic sclerosis (SSc) nailfold videocapillaroscopy (NVC); allows diagnostic and follow-up of microvascular damage. Distinct NVC patterns have been identified for the evaluation of severity of SSc microvascular damage. The objective of this study is to evaluate the modification of the microvasculature under Bosentan therapy in SSc patients with pulmonary arterial hypertension (PAH). Nine patients with PAH related to SSc in New York Heart Association classes III-IV were treated with Bosentan 125 mg twice a day. NVC optical probe videocapillaroscopy equipped with 100× and 200× contact lenses and connected to image analyse software was performed before and after 12 months of Bosentan therapy to evaluate the modification of microvasculature. Nine PAH SSc patients treated with Iloprost were used as controls. Before Bosentan therapy, seven patients showed at NVC severe loss of capillaries with large avascular areas and vascular architectural disorganisation which are typically "late" SSc pattern. After 12 months of Bosentan, NVC pattern changed in seven patients from "late" into "active" SSc pattern. The disappearance of avascular areas and capillary haemorrhages was the most striking result. Two patients had an "active" SSc pattern, not modified by Bosentan treatment. These data show that Bosentan may improve NVC pattern in SSC and the presence of new capillaries suggests that it may favour angiogenesis. Bosentan may improve and stabilise the microvasculature in long-term treatment modulating the structural modifications detected by NVC.

  11. In Vivo Monitoring of Hemodynamic Changes during Clogging and Unclogging of Blood Supply for the Application of Clinical Shock Detection

    Science.gov (United States)

    Kanawade, Rajesh; Stelzle, Florian; Schmidt, Michael

    This paper presents a novel methodology in early detection of clinical shock by monitoring hemodynamic changes using diffuse reflectance measurement technique. Detailed prototype of the reflectance measurement system and data analysis technique of hemodynamic monitoring was carried out in our laboratory. The real time in-vivo measurements were done from the index finger. This study demonstrates preliminary results of real time monitoring of reduced/- oxyhemoglobin changes during clogging and unclogging of blood flow in the finger tip. The obtained results were verified with pulse-oximeter values, connected to the tip of the same index finger.

  12. Microvascular and immunological studies in Raynaud's phenomenon.

    NARCIS (Netherlands)

    Houtman, Pieternella Maria

    1985-01-01

    The purpose of this thesis was to investigate the diagnostic significance of microvascular abnormalities - as observed in the nailfold - in patients with RP with respect to the presence or development of a connective tissue disease. In addition, we investigated whether the observed abnormalities wer

  13. Microvascular and immunological studies in Raynaud's phenomenon.

    NARCIS (Netherlands)

    Houtman, Pieternella Maria

    1985-01-01

    The purpose of this thesis was to investigate the diagnostic significance of microvascular abnormalities - as observed in the nailfold - in patients with RP with respect to the presence or development of a connective tissue disease. In addition, we investigated whether the observed abnormalities wer

  14. How to assess microvascular structure in humans.

    Science.gov (United States)

    Rizzoni, Damiano; Aalkjaer, Christian; De Ciuceis, Carolina; Porteri, Enzo; Rossini, Claudia; Rosei, Claudia Agabiti; Sarkar, Annamaria; Rosei, Enrico Agabiti

    2011-12-01

    Structural alterations of subcutaneous small resistance arteries, as indicated by an increased media to lumen ratio, are frequently present in hypertensive and/or diabetic patients. However, the evaluation of microvascular structure is not an easy task. Among the methods that may be applied to humans, plethysmographic evaluation of small arteries and wire or pressure micromyography were extensively used in the last decades. Media to lumen ratio of small arteries evaluated by micromyography was demonstrated to possess a strong prognostic significance; however, its extensive evaluation is limited by the invasiveness of the assessment, since a biopsy of subcutaneous fat is needed. Non-invasive approaches were then proposed, including capillaroscopy, which provides information about microvascular rarefaction. Recently, the interest of investigators has focused on the retinal microvascular bed. In particular, a non-invasive measurement of wall thickness to internal lumen ratio of retinal arterioles using scanning laser Doppler flowmetry has been recently introduced. Preliminary data suggest a fairly good agreement between this approach and micromyographic measurements, generally considered the gold standard approach. Therefore, the evaluation of microvascular structure is progressively moving from bench to bedside, and it could represent, in the immediate future, an evaluation to be performed in all hypertensive patients, in order to obtain a better stratification of cardiovascular risk. © 2011 Adis Data Information BV. All rights reserved.

  15. Noninvasive quantification of the differential portal and arterial contribution to the liver blood supply from PET measurements using the 11C-acetate kinetic model.

    Science.gov (United States)

    Chen, Sirong; Feng, Dagan

    2004-09-01

    Our recent research has demonstrated that 11C-acetate could be a complementary tracer to 18F-fluorodeoxyglucose (FDG) in positron emission tomography (PET) imaging of hepatocellular carcinoma (HCC). In our previous modeling study, a three-compartment four-parameter model with a fixed contribution ratio of the liver's two blood supplies was proposed to characterize the kinetic behavior of 11C-acetate in liver. However, in real pathology, both tumor and nontumor liver tissue can be heterogeneous in the distribution and proportion of the two blood supplies. To further improve the accuracy of quantitative analysis, the actual proportion of the hepatic artery and portal vein (PV) in different regions of interest (ROIs) was investigated in this study. An extra parameter av was included in the model input function to describe the contribution of PV to the liver. Ten ROIs extracted from six patients were used to test the models with fixed/nonfixed weighted dual-input function. The weighted nonlinear least squares algorithm was used to estimate all of the parameters. Evaluation of the adequacy of the two models was conducted and the computer simulation was performed to test the estimation accuracy of the new model. The forward clearance K was also estimated by the linear Patlak method. The results show that the model with parameter av in the input function was more suitable for mapping the tracer time activity curves. Moreover, the estimated av value fits the practical physiological and pathological conditions well and could be a potential candidate to provide useful additional diagnostic information for the early detection of hepatic metastases.

  16. What Causes Coronary Microvascular Disease?

    Science.gov (United States)

    ... inside the arteries. Risk factors for atherosclerosis include: Diabetes . It is a disease in which the body’s blood sugar level is too high because the body doesn’t make enough insulin or doesn’t use its insulin properly. Family history of early heart disease . Your risk of atherosclerosis ...

  17. Dysregulation of coronary microvascular reactivity in asymptomatic patients with type 2 diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Momose, Mitsuru; Neverve, Jodi; Nekolla, Stephan G.; Schwaiger, Markus; Bengel, Frank M. [Nuklearmedizinische Klinik und Poliklinik der Technischen Universitaet Muenchen, Klinikum rechts der Isar, Ismaninger Strasse 22, 81675 Munich (Germany); Abletshauser, Claudia [Department of Medicine, Novartis Pharma GmbH, Nuernberg (Germany); Schnell, Oliver; Standl, Eberhard [Institut fuer Diabetesforschung, Munich (Germany)

    2002-12-01

    In diabetic patients, a number of studies have suggested an impairment of vascular reactivity in response to vasodilatory stimuli. The pattern of dysregulation at the coronary microcirculatory level, however, has not been clearly defined. Thus, it was the aim of this study to characterise coronary microvascular function non-invasively in a homogeneous group of asymptomatic type 2 diabetic patients. In 46 patients with type 2 diabetes, myocardial blood flow (MBF) was quantified at baseline, in response to cold pressor test (CPT) and during adenosine-mediated vasodilation using positron emission tomography and nitrogen-13 ammonia. None of the patients had been treated with insulin, and none had symptoms of cardiac disease. Decreased MBF during CPT, indicating microvascular dysregulation, was observed in 16 patients (CPT-), while 30 patients demonstrated increased MBF during CPT (CPT+). Response to CPT was mildly, but significantly correlated with response to adenosine (r=0.44, P=0.0035). There was no difference in HbA1c, serum lipid levels or serum endothelial markers between the groups. Microvascular dysregulation in the CPT- group was associated with elevated baseline MBF (P<0.0001), reduced baseline vascular resistance (P=0.0026) and an abnormal increase in resistance during CPT (P=0.0002). In conclusion, coronary microvascular dysregulation is present in approximately one-third of asymptomatic, non-insulin-treated type 2 diabetic patients. Elevated baseline blood flow and reduced microvascular resistance at rest are characteristics of this dysregulation. These data suggest a state of activation of endothelial-dependent vasodilation at baseline which appears to limit the flow response to stress conditions. (orig.)

  18. The EASTR Study: indications for transfusion and estimates of transfusion recipient numbers in hospitals supplied by the National Blood Service.

    Science.gov (United States)

    Wells, A W; Llewelyn, C A; Casbard, A; Johnson, A J; Amin, M; Ballard, S; Buck, J; Malfroy, M; Murphy, M F; Williamson, L M

    2009-12-01

    This study provides data on National Blood Service (NBS) red blood cell (RBC, n = 9142), platelet (PLT, n = 4232) and fresh frozen plasma (FFP, n = 3584) recipients independently sampled by monthly quota from 29 representative hospitals over 12 months in 2001-2002. Hospitals were stratified by size according to total yearly RBC issues. Transfusion indications were chosen from diagnostic and procedural codes, and recipients grouped into Epidemiology and Survival of Transfusion Recipients Case-mix Groups (E-CMGs). The main E-CMGs were digestive [19% of RBC recipients; including 5% gastrointestinal (GI) bleeds and 3% colorectal surgery], musculoskeletal (15%; 12% hip and knee replacement), haematology (13%) and obstetrics and gynaecology (10%). Renal failure, fractured neck of femur, cardiac artery by-pass grafting (CABG) and paediatrics, each accounted for 3-4% recipients. FFP recipients: the main E-CMGs were digestive (21% of FFP recipients; including 7% GI bleeds and 3% colorectal surgery), hepatobiliary (15%; 7% liver disease and 2% liver transplant), cardiac (12%) and paediatrics (9%) The renal, paediatrics, vascular and haematology E-CMGs each had 6-7% of recipients. PLT recipients: the main E-CMGs were haematology (27% of PLT recipients; including 9% lymphoma and 8% acute leukaemia), cardiac (17%), paediatrics (13%), hepatobiliary (10%) and digestive (9%). Back-weighting gave national estimates of 433 000 RBC, 57 500 FFP and 41 500 PLT recipients/year in England and North Wales, median age 69, 64 and 59 years, respectively. Digestive and hepatobiliary indications emerged as the top reason for transfusion in RBC and FFP recipients, and was also a frequent indication in PLT recipients.

  19. [Structure of nocturnal sleep if there is a violation of the blood supply in the territory of internal carotid artery].

    Science.gov (United States)

    Berezina, I Iu; Sumskiĭ, L I; Kudriashova, N E

    2013-01-01

    The work examines the influence of degree ofstenosis or occlusion of the internal carotid artery (ICA) of noc- turnal sleep and discusses possible neurophysiological mechanisms of sleep disorders when blood flow in ca- rotid system. 24 patients (19 male and 5 female) were examined. The mean age of men was 49.75 ± 6.55; women--46.67 ± 5.86. Six patients with a single unilateral internal carotid stenosis (ICA) 50%; seven patients--stenosis of ICA 50-70%; eleven patients--occlusion of ICA completed the study. Polysomnography was recorded with "Neuro-Spectr-5/EP" ("NeuroSoft", Russia) and "Delta Flash" ("Deltamed", France) according to international recommendation. Stages of sleep were identified according to Re- chtschaffen A., Kales A. (1968) criteria. Patients were asked to fill in the questionnaire prior to clinical and polysomnographic evaluation. Regional cerebral blood flow (mL/100g/min) with 99mTechnetium (Gamma-camera, DST-Xli "General electric", USA) was study by single photon emission CT imaging. The result of this study showed that with stenosis of the ICA to 50% structure of nocturnal sleep is not changed: records all phases and stages of sleep, quantitative parameters that match the normative data; or decline in the representation of only the stage II sleep; at stenosis ICA of 50-70% is violation of mostly stage II sleep and slow-wave sleep, and with occlusion ICA violation slow-wave sleep and in 45% of cases--REM-sleep.

  20. Microvascular pericytes in healthy and diseased kidneys

    Directory of Open Access Journals (Sweden)

    Pan SY

    2014-01-01

    Full Text Available Szu-Yu Pan,1,2 Yu-Ting Chang,3 Shuei-Liong Lin1,31Renal Division, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; 2Department of Internal Medicine, National Taiwan University Hospital, Yun-Lin Branch, Yun-Lin, Taiwan; 3Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, TaiwanAbstract: Pericytes are interstitial mesenchymal cells found in many major organs. In the kidney, microvascular pericytes are defined anatomically as extensively branched, collagen-producing cells in close contact with endothelial cells. Although many molecular markers have been proposed, none of them can identify the pericytes with satisfactory specificity or sensitivity. The roles of microvascular pericytes in kidneys were poorly understood in the past. Recently, by using genetic lineage tracing to label collagen-producing cells or mesenchymal cells, the elusive characteristics of the pericytes have been illuminated. The purpose of this article is to review recent advances in the understanding of microvascular pericytes in the kidneys. In healthy kidney, the pericytes are found to take part in the maintenance of microvascular stability. Detachment of the pericytes from the microvasculature and loss of the close contact with endothelial cells have been observed during renal insult. Renal microvascular pericytes have been shown to be the major source of scar-forming myofibroblasts in fibrogenic kidney disease. Targeting the crosstalk between pericytes and neighboring endothelial cells or tubular epithelial cells may inhibit the pericyte-myofibroblast transition, prevent peritubular capillary rarefaction, and attenuate renal fibrosis. In addition, renal pericytes deserve attention for their potential to produce erythropoietin in healthy kidneys as pericytes stand in the front line, sensing the change of oxygenation and hemoglobin concentration. Further delineation of the mechanisms underlying the

  1. Microanatomy on blood supply system in human knee cruciate ligament%人膝关节交叉韧带血供的显微解剖学研究

    Institute of Scientific and Technical Information of China (English)

    何正; 张祚勇; 赵晓东; 张勇

    2011-01-01

    Objective To investigate the configuration of the blood supply system in human knee cruciate ligament. Methods Twelve cruciate ligaments derived from the knee joints of 6 healthy adult cadavers were observed under naked eyes, and then dissected and observed under a microscope. Three groups of anterior cruciate ligaments and posterior cruciate ligaments, randomly selected from the twelve cruciate ligaments, were observed through histotomy and HE staining. Results Blood vessels were found throughout the human knee cruciate ligaments, and the calibers of the blood vessels varied between 0.03 ±0.01 mm and 0.09 ±0.02 mm in different segments. Blood vessels and adipose tissues were abundantly found in the bands between the anterior cruciate ligaments and posterior cruciate ligaments, and the surface blood vessel calibers were not larger than 0.18 ± 0.04 mm. Conclusiorn The human knee cruciate ligaments possess enough blood vessels to show promise in self repair.%目的 探讨人类膝关节交叉韧带血供系统的具体形态.方法 对12侧交叉韧带健康成人尸体膝关节进行肉眼和手术显微镜下解剖、组织学断层切片观察.结果 交叉韧带全段均可见血管纵行交错分布,血管口径呈节段性变化,血管口径(0.03±0.01)~(0.09±0.02)mm.交叉韧带间束中存在大量的血管及脂肪组织,其表面血管口径最大为(0.18±0.04)mm.结论 交叉韧带本身拥有足够充分的血供来源,存在自我修复的可能.

  2. Radiation-induced blood-brain barrier changes: pathophysiological mechanisms and clinical implications.

    Science.gov (United States)

    d'Avella, D; Cicciarello, R; Angileri, F F; Lucerna, S; La Torre, D; Tomasello, F

    1998-01-01

    The pathophysiology of whole-brain radiation (WBR) toxicity remains incompletely understood. The possibility of a primary change in blood-brain barrier (BBB) associated with microvascular damage was investigated. Rats were exposed to conventional fractionation in radiation (200 +/- cGy/d, 5d/wk; total dose, 4,000 cGy). BBB changes were assessed by means of the quantitative 14C-alpha-aminoisobutyric acid (AIB) technique coupled with standard electron microscopy (EM) and morphometric techniques as well as studies of the transcapillary passage of horseradish peroxidase (HRP). At 15 days after WBR, AIB transport across BBB increased significantly in cerebral cortex. EM disclosed vesicular transport of HRP across the intact endothelium without opening of the tight junctions. Ninety days after WBR, well-defined alterations of the microvasculature were observed. The main feature of cortical microvessels was their collapsed aspect, associated with perivascular edema containing cell debris. Data suggest a possible association between damage of the microvascular/glial unit of tissue injury and development of radiation-induced brain cerebral dysfunction. We hypothesize the following sequence of pathophysiological events: WBR causes an early increase in BBB permeability, which produces perivascular edema and microvascular collapse. The interference with microcirculation affects blood flow and energy supply to the tissue, resulting in structural damage on an ischemic/dysmetabolic basis.

  3. Adipose tissue-derived microvascular fragments from aged donors exhibit an impaired vascularisation capacity

    Directory of Open Access Journals (Sweden)

    MW Laschke

    2014-10-01

    Full Text Available Adipose tissue-derived microvascular fragments are promising vascularisation units for applications in the field of tissue engineering. Elderly patients are the major future target population of such applications due to an increasing human life expectancy. Therefore, we herein investigated the effect of aging on the fragments’ vascularisation capacity. Microvascular fragments were isolated from epididymal fat pads of adult (8 months and aged (16 months C57BL/6 donor mice. These fragments were seeded onto porous polyurethane scaffolds, which were implanted into dorsal skinfold chambers to study their vascularisation using intravital fluorescence microscopy, histology and immunohistochemistry. Scaffolds seeded with fragments from aged donors exhibited a significantly lower functional microvessel density and intravascular blood flow velocity. This was associated with an impaired vessel maturation, as indicated by vessel wall irregularities, constantly elevated diameters and a lower fraction of CD31/α-smooth muscle actin double positive microvessels in the implants’ border and centre zones. Additional in vitro analyses revealed that microvascular fragments from adult and aged donors do not differ in their stem cell content as well as in their release of angiogenic growth factors, survival and proliferative activity under hypoxic conditions. However, fragments from aged donors exhibit a significantly lower number of matrix metalloproteinase -9-positive perivascular cells. Taken together, these findings demonstrate that aging is a crucial determinant for the vascularisation capacity of isolated microvascular fragments.

  4. Transport and regulation mechanism of the colloidal gold liposomes in the brain microvascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    WANG Lipeng; CHANG Yanzhong

    2015-01-01

    Objective:Blood-brain barrier is the key barrier of brain in the innate immune. It can prevent the harmful substances from the blood into the brain. In order to keep the brain in a relatively stable environment and maintain the normal function of the nervous system, it can also pump harmful substances or excess substances outside the brain selectively. Among them, brain microvascular endothelial cell tissue is a key part in the blood-brain barrier's function. The number of the patients with central nervous system ( CNS) diseases increased year by year. The therapeutic drug is usually inhibited by the blood-brain barrier and is difficult to work. Therefore, how to modify the drug and to make it easier to cross the blood brain barrier is the key point to cure CNS. At present, more than 95% research focus only on how nano drugs can enter the cell, the way and efficiency to enter the cell and the research of effect of nano drug etc. For the process of drug carrier in endocytosis, intracellular transport and release and regulation of research are rarely reported. Clathrin and P-glycoprotein are related protein in endo-cytosis and exocytosis with nano drug. Clathrin is located on the plasma membrane. It participates in endocytosis of some nutrients, and maybe the entry into the cell of some drugs. P-glycoprotein is located in the membrane of cer-ebral capillary endothelial cells. It can efflux drugs relying on ATP. Although there is a certain understanding of the cell in the inner swallow and efflux. But the process of the liposome drug is not clear. To solve the above prob-lems, using colloidal gold liposome nano materials to trace liposome's transport and regulation mechanism in brain microvascular endothelial cells, and study endocytosis, release, distribution and regulation mechanism of nano lipo-somes in brain microvascular. The solution of this problem can guide to construct reasonable drug carrier, and look forward to clarifing the molecular basis and mechanism of

  5. Applied anatomical study of the vascularized ulnar nerve and its blood supply for cubital tunnel syndrome at the elbow region.

    Science.gov (United States)

    Li, Mei-Xiu-Li; He, Qiong; Hu, Zhong-Lin; Chen, Sheng-Hua; Lv, Yun-Cheng; Liu, Zheng-Hai; Wen, Yong; Peng, Tian-Hong

    2015-01-01

    Cubital tunnel syndrome is often accompanied by paresthesia in ulnar nerve sites and hand muscle atrophy. When muscle weakness occurs, or after failure of more conservative treatments, anterior transposition is used. In the present study, the ulnar nerve and its blood vessels were examined in the elbows of 18 adult cadavers, and the external diameter of the nutrient vessels of the ulnar nerve at the point of origin, the distances between the origin of the vessels and the medial epicondyle of the humerus, and the length of the vessels accompanying the ulnar nerve in the superior ulnar collateral artery, the inferior ulnar collateral artery, and the posterior ulnar recurrent artery were measured. Anterior transposition of the vascularized ulnar nerve was performed to treat cubital tunnel syndrome. The most appropriate distance that the vascularized ulnar nerve can be moved to the subcutaneous tissue under tension-free conditions was 1.8 ± 0.6 cm (1.1-2.5 cm), which can be used as a reference value during the treatment of cubital tunnel syndrome with anterior transposition of the vascularized ulnar nerve.

  6. Applied anatomical study of the vascularized ulnar nerve and its blood supply for cubital tunnel syndrome at the elbow region

    Directory of Open Access Journals (Sweden)

    Mei-xiu-li Li

    2015-01-01

    Full Text Available Cubital tunnel syndrome is often accompanied by paresthesia in ulnar nerve sites and hand muscle atrophy. When muscle weakness occurs, or after failure of more conservative treatments, anterior transposition is used. In the present study, the ulnar nerve and its blood vessels were examined in the elbows of 18 adult cadavers, and the external diameter of the nutrient vessels of the ulnar nerve at the point of origin, the distances between the origin of the vessels and the medial epicondyle of the humerus, and the length of the vessels accompanying the ulnar nerve in the superior ulnar collateral artery, the inferior ulnar collateral artery, and the posterior ulnar recurrent artery were measured. Anterior transposition of the vascularized ulnar nerve was performed to treat cubital tunnel syndrome. The most appropriate distance that the vascularized ulnar nerve can be moved to the subcutaneous tissue under tension-free conditions was 1.8 ± 0.6 cm (1.1-2.5 cm, which can be used as a reference value during the treatment of cubital tunnel syndrome with anterior transposition of the vascularized ulnar nerve.

  7. [Blood supply to the liver in the human after 1 MAC desflurane in comparison with isoflurane and halothane].

    Science.gov (United States)

    Schindler, E; Müller, M; Zickmann, B; Kraus, H; Reuner, K H; Hempelmann, G

    1996-08-01

    Objective of this investigation was to compare the effects of the new inhalation agent desflurane with equipotent doses of isoflurane and halothane on hepatic blood flow (tHBF). 36 Patients scheduled for elective aortocoronary bypass grafting were enrolled to the study. tHBF was assessed by plasma clearance and hepatic extraction of indocyanine green, and standard haemodynamic parameters were measured by thermodilution technique. The measurements were performed awake and after intubation at equilibration of 1 MAC. All measurements were terminated before skin incision. We found a significant decrease of tHBF in all patients regardless of the inhalation agent used (H 918 ml/min +/- 107 to 625 ml/min +/- 181, I 930 ml/min +/- 195 to 637 ml/min +/- 137, D 940 ml/min +/- 129 to 677 ml/min +/- 122). The tHBF in relation to cardiac output also decreased significantly (H 17% +/- 5 to 14% +/- 3, I 16% +/- 3 to 14% +/- 5, D 20% +/- 5 to 18% +/- 6). No difference was seen between the groups according to tHBF and haemodynamics. The results of this study suggest that all inhalation agents included in the study significantly decreased tHBF during anaesthesia with the concentration of 1 MAC.

  8. Applied anatomical study of the vascularized ulnar nerve and its blood supply for cubital tunnel syndrome at the elbow region

    Institute of Scientific and Technical Information of China (English)

    Mei-xiu-li Li; Qiong He; Zhong-lin Hu; Sheng-hua Chen; Yun-cheng Lv; Zheng-hai Liu; Yong Wen; Tian-hong Peng

    2015-01-01

    Cubital tunnel syndrome is often accompanied by paresthesia in ulnar nerve sites and hand muscle atrophy. When muscle weakness occurs, or after failure of more conservative treatments, anterior transposition is used. In the present study, the ulnar nerve and its blood vessels were examined in the elbows of 18 adult cadavers, and the external diameter of the nutrient vessels of the ulnar nerve at the point of origin, the distances between the origin of the vessels and the medial epicondyle of the humerus, and the length of the vessels accompanying the ulnar nerve in the superior ulnar collateral artery, the inferior ulnar collateral artery, and the posterior ulnar recurrent artery were measured. Anterior transposition of the vascularized ulnar nerve was per-formed to treat cubital tunnel syndrome. The most appropriate distance that the vascularized ulnar nerve can be moved to the subcutaneous tissue under tension-free conditions was 1.8 ± 0.6 cm (1.1–2.5 cm), which can be used as a reference value during the treatment of cubital tunnel syndrome with anterior transposition of the vascularized ulnar nerve.

  9. Effects of nicardipine and nisoldipine on myocardial metabolism, coronary blood flow and oxygen supply in angina pectoris.

    Science.gov (United States)

    Rousseau, M F; Vincent, M F; Van Hoof, F; Van den Berghe, G; Charlier, A A; Pouleur, H

    1984-12-01

    The effects of the calcium antagonists nicardipine and nisoldipine on left ventricular (LV) metabolism were analyzed in 32 patients with angina pectoris. Measurements were made at a fixed heart rate under the basal state and during a cold pressor test (CPT). After administration of the drugs, coronary blood flow increased significantly and the mean aortic pressure decreased by 10% (p less than 0.01) in the basal state and by 11% (p less than 0.01) during CPT. Despite the reduction in pressure-rate product, myocardial oxygen consumption was unchanged in the basal state (18 +/- 4 vs 19 +/- 4 ml/min, difference not significant) and during CPT (21 +/- 5 vs 21 +/- 5 ml/min, difference not significant); this discrepancy between a reduced pressure-rate product and an unchanged oxygen consumption was also noted when nicardipine was given after propranolol (0.1 mg/kg; 12 patients). Both agents also increased LV lactate uptake, particularly during CPT (+13 mumol/min, p less than 0.05 vs control CPT) and reduced LV glutamine production. In 10 patients in whom 14C-lactate was infused, the chemical LV lactate extraction ratio increased more than the 14C-lactate extraction ratio after administration of the drugs, indicating a reduction in LV lactate production. The data are consistent with the hypothesis that nicardipine and nisoldipine improve perfusion and aerobic metabolism in chronically ischemic areas, resulting in an augmented oxygen consumption and in a reduced lactate production.

  10. Goal-directed fluid therapy for microvascular free flap reconstruction following mastectomy: A pilot study

    OpenAIRE

    Funk, Duane; Bohn, James; Mutch, WAC; Hayakawa, Tom; Buchel, Edward W

    2015-01-01

    Fluid replacement is an important aspect of surgery and is particularly challenging in patients undergoing microvascular free flap reconstruction. The use of vasopressors can compromise blood flow to the flap, a problem also encountered with inadequate volume replacement, which can lead to ischemia and flap loss. However, excessive perioperative fluid administration may lead to flap loss resulting from venous engorgement and flap edema. This uncertainty, in part, prompted the authors of this ...

  11. Early postoperative bone scintigraphy in the evaluation of microvascular bone grafts in head and neck reconstruction

    Directory of Open Access Journals (Sweden)

    Poissonnet Gilles

    2007-04-01

    Full Text Available Abstract Background Bone scintigraphy was performed to monitor anastomotic patency and bone viability. Methods In this retrospective study, bone scans were carried out during the first three postoperative days in a series of 60 patients who underwent microvascular bone grafting for reconstruction of the mandible or maxilla. Results In our series, early bone scans detected a compromised vascular supply to the bone with high accuracy (p Conclusion When performing bone scintigraphy during the first three postoperative days, it not only helps to detect complications with high accuracy, as described in earlier studies, but it is also an additional reliable monitoring tool to decide whether or not microvascular revision surgery should be performed. Bone scans were especially useful in buried free flaps where early postoperative monitoring depended exclusively on scans. According to our experience, we recommend bone scans as soon as possible after surgery and immediately in cases suspicious of vascularized bone graft failure.

  12. Phase coherence of 0.1 Hz microvascular tone oscillations during the local heating

    Science.gov (United States)

    Mizeva, I. A.

    2017-06-01

    The origin of the mechanisms of blood flow oscillations at low frequencies is discussed. It is known that even isolated arteriole demonstrates oscillations with the frequency close to 0.1 Hz, which is caused by the synchronous activity of myocyte cells. On the other hand, oscillations with close frequency are found in the heart rate, which are associated with quite different mechanism. The main purpose of this work is to study phase coherence of the blood flow oscillations in the peripheral vessels under basal and perturbed conditions. Local heating which locally influences the microvascular tone, as one of currently elucidated in sufficient detail physiological test, was chosen. During such provocation blood flow though the small vessels significantly increases because of vasodilation induced by the local synthesis of nitric oxide. In the first part of the paper microvascular response to the local test is quantified in healthy and pathological conditions of diabetes mellitus type 1. It is obtained that regardless of the pathology, subjects with high basal perfusion had lower reserve for vasodilation, which can be caused by the low elasticity of microvascular structure. Further synchronization of pulsations of the heated and undisturbed skin was evaluated on the base of wavelet phase coherency analysis. Being highly synchronised in basal conditions 0.1 Hz pulsations became more independent during heating, especially during NO-mediated vasodilation.

  13. Clinical reference value of retinal microvascular changes in patients with cerebral microbleeds

    Directory of Open Access Journals (Sweden)

    Ji-Yuan Guo

    2014-12-01

    Full Text Available AIM: To study clinical reference value of retinal microvascular changes in patients with cerebral microbleeds(CMBsand discuss its clinical significance. METHODS:From January 2012 to December 2013, 125 hospitalized patients were collected, including 81 cases were male, 44 cases were female, mean age 76.3±11.2 years old. For all patients, functions of liver and kidney, blood-lipoids, blood sugar and blood biochemical examination were tested, and fundus photography and cerebral MR was done. According to the fundus camera eyes, retinal arteriolar equivalent(RAE, retinal venular equivalent(RVE, retinal vein diameter ratio(AVRand arteriovenous crossing sign(AVNwere identified, CMBs were classified with cerebral MRI. All the data were processed by SPSS statistical software. RESULTS: The central retinal arteriolar equivalent(CRAE, central retinal venular equivalent(CRVEand AVR values in the eyes were found no statistical difference(PPCOCLUSION: The results show that retinal microvascular changes, especially small retinal vein arteriovenous cross width, and arteriovenous crossing phenomenon, in which CMBs will happen more likely. After sex, age, hypertension and hyperglycemia in patients with traditional cardiovascular risk factors being ruled out, the retinal microvascular changes are still relatively factors of CMB's occurrence.

  14. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows

    CERN Document Server

    Brust, M; Thiebaud, M; Flormann, D; Verdier, C; Kaestner, L; Laschke, M W; Selmi, H; Benyoussef, A; Podgorski, T; Coupier, G; Misbah, C; Wagner, C

    2014-01-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These pers...

  15. Detection of microvascular and tri-truncal coronaries injuries by quantitative cardiac PET/CT with Rb-82;Detection des lesions coronaires microvasculaires et tritronculaires par TEP-CT cardiaque quantitative au Rb-82

    Energy Technology Data Exchange (ETDEWEB)

    Dunet, V.; Allenbach, G.; Soubeyran, V.; Kosinski, M.; Bischof-Delaloye, A.; Prior, J. [CHU de Vaudois, Departement de medecine nucleaire, Lausanne (Switzerland); Camus, F. [CHU de Vaudois, institut de radiophysique appliquee, Lausanne (Switzerland)

    2010-05-15

    The results show that up to 1 in 5 investigated by PET / CT with Rb-82 with myocardium blood rate quantification shows affected myocardium flux reserve linked to microvascular or tri-truncal affect undiagnosed by semi-quantitative analysis

  16. Invasive assessment of coronary microvascular dysfunction in hypertrophic cardiomyopathy: the index of microvascular resistance

    Energy Technology Data Exchange (ETDEWEB)

    Gutiérrez-Barrios, Alejandro, E-mail: aleklos@hotmail.com [Cardiology Department, Jerez Hospital, Jerez (Spain); Camacho-Jurado, Francisco [Cardiology Department, Punta Europa Hospital, Algeciras (Spain); Díaz-Retamino, Enrique; Gamaza-Chulián, Sergio; Agarrado-Luna, Antonio; Oneto-Otero, Jesús; Del Rio-Lechuga, Ana; Benezet-Mazuecos, Javier [Cardiology Department, Jerez Hospital, Jerez (Spain)

    2015-10-15

    Summary: We present a review of microvascular dysfunction in hypertrophic cardiomyopathy (HCM) and an interesting case of a symptomatic familial HCM patient with inducible ischemia by single photon emission computed tomography. Coronary angiography revealed normal epicardial arteries. Pressure wire measurements of fractional flow reserve (FFR), coronary flow reserve (CFR) and index of microvascular resistance (IMR) demonstrated a significant microcirculatory dysfunction. This is the first such case that documents this abnormality invasively using the IMR. The measurement of IMR, a novel marker of microcirculatory dysfunction, provides novel insights into the pathophysiology of this condition. - Highlights: • Microvascular dysfunction is a common feature in hypertrophic cardiomyopathy (HCM) and represents a strong predictor of unfavorable outcome and cardiovascular mortality. • The index of microvascular resistance (IMR) is a new method for invasively assessing the state of the coronary microcirculation using a single pressure-temperature sensor-tipped coronary wire. • However assessment of IMR in HCM has not been previously reported. We report a case in which microvascular dysfunction is assessed by IMR. This index may be useful in future researches of HCM.

  17. Treatment of hemimasticatory spasm with microvascular decompression.

    Science.gov (United States)

    Wang, Yong-Nan; Dou, Ning-Ning; Zhou, Qiu-Meng; Jiao, Wei; Zhu, Jin; Zhong, Jun; Li, Shi-Ting

    2013-01-01

    Hemimasticatory spasm is a rare disorder characterized by paroxysmal involuntary contraction of the jaw-closing muscles. As the ideology and pathogenesis of the disease are still unclear, there has been no treatment that could give rise to a good outcome so far. Herein, we tried to use surgical management to cure the disease. Six patients with the disease were included in this study. These patients underwent microvascular decompression of the motor fibers of the trigeminal root. After the operation, all faces of the patients felt relaxed at varied degrees, except for 1 patient. Our study showed that microvascular decompression of the trigeminal nerve could lead to a better outcome. However, a control study with a large sample is needed before this technique is widely used.

  18. 豚鼠内淋巴囊供血血管与内淋巴囊血流量的研究%Study of blood supply and blood flow of endolymphatic sac in guinea pigs

    Institute of Scientific and Technical Information of China (English)

    陈继川; 刘兆华; 徐伟恒

    2001-01-01

    Objective To study the relationship of blood flow (ESBF) and theposterior meningeal artery (PMA) and posterior vestibular artery (PVA) in endolymphatic sac of guinea pigs. Methods After the ligature of PMA or PVA respectively, the ESBF of 16 guinea pigs under different blood supplies was measured with biological microsphere technique in the normal state. Results There was significant difference in the various blood supplies (P<0.01). The ESBF was (1.549 1±0.526 6) μl/min in normal, (1.075 225±0.370 3) μ1/min in PVA ligature (15.8% less than the normal), and (0.355 937 5±0.246 9) μ1/min in PMA ligature (declined by 76% compared with the normal). The ratio of the three blood flow was QNormal∶QNon-PVA∶QNon-PMA=4.3∶3∶1. Conclusion PMA and PVA are the main portions of blood supply of ESBF. PMA from external carotid artery system contributes more than PVA from internal auditory artery system to ESBF.%目的 探讨豚鼠内淋巴囊供血血管脑膜后动脉(PMA)、前庭后动脉(PVA)与内淋巴囊血流量的关系。方法 分别阻断PMA与PVA并在不同供血状态下对16只豚鼠的内淋巴囊血流量进行检测,数据做统计学分析。结果 不同供血状态下内淋巴囊血流量差异有显著性(P<0.01),其中正常内淋巴囊血流量为(1.5491±0.5266)μl/min,阻断PVA后内淋巴囊血流量为(1.075225±0.3703)μl/min,较正常内淋巴囊血流量下降约15.8%;阻断PMA后内淋巴囊血流量为(0.3559375±0.2469)μl/min,较正常内淋巴囊血流量下降约76%;血流量之比为Q正常∶Q阻PVA∶Q阻PMA=4.3∶3∶1。结论 PMA及PVA两大分支血流量是构成整个内淋巴囊血流量的主体,其中以来自颈外动脉系统的PMA对内淋巴囊血流量的影响较来自内听动脉系统的PVA显著。

  19. Atrial supply-demand balance in healthy adult pigs: coronary blood flow, oxygen extraction, and lactate production during acute atrial fibrillation.

    Science.gov (United States)

    van Bragt, Kelly A; Nasrallah, Hussein M; Kuiper, Marion; Luiken, Joost J; Schotten, Ulrich; Verheule, Sander

    2014-01-01

    Little is known about how atrial oxygen supply responds to increased demand, and under which conditions it falls short (supply-demand mismatch). Here, we have investigated the vasodilator response, oxygen extraction, and lactate production of the left atrium (LA) and left ventricle (LV) in response to atrial pacing and atrial fibrillation (AF). Series A (n = 9 Dutch landrace pigs) was instrumented to measure LA and LV vascular conductance in branches of the circumflex artery. Coronary conductance reserve (CCR) was calculated as the ratio between conductance during adenosine infusion and baseline. Series B (n = 7) was instrumented with sampling catheters in LA and LV veins for determination of blood gases and lactate levels. LA CCR (1.76 ± 0.14) was significantly lower than LV CCR (3.16 ± 0.27, P = 0.002). However, basal oxygen extraction was lower in LA (27 ± 3%) than that in the LV (58 ± 6%, P = 0.0006), indicating a larger extraction reserve in the LA than that in the LV (4.68 ± 0.84 vs. 1.88 ± 0.26, P = 0.01). Atrial pacing caused an increase in LA conductance (Series A) and oxygen extraction (Series B). AF increased LA vascular conductance to 177 ± 14% at 1 min, 168 ± 14 at 5 min, and 164 ± 31% at 10 min of AF (P < 0.05 vs. baseline). Atrial oxygen extraction also increased from 26 ± 3% at baseline to 63 ± 5% (P < 0.01) at 5 min and 60 ± 11% (P < 0.01) at 10 min of AF. Arterio-venous lactate difference increased significantly (P = 0.02) during AF. In healthy pigs, the LA has a lower CCR, but a higher extraction reserve compared with the LV. Although both reserves were recruited during AF, atrial lactate production increased significantly.

  20. Β-alanine and l-histidine transport across the inner blood-retinal barrier: potential involvement in L-carnosine supply.

    Science.gov (United States)

    Usui, Takuya; Kubo, Yoshiyuki; Akanuma, Shin-Ichi; Hosoya, Ken-Ichi

    2013-08-01

    The supply of L-carnosine, a bioactive dipeptide of β-alanine and l-histidine, to the retina across the blood-retinal barrier (BRB) was studied. The in vivo and in vitro studies revealed low uptake activities for [(3)H]Gly-Sar, a representative dipeptide, suggesting that l-carnosine transport plays only a minor role at the BRB. The in vivo study using rats showed approximately 18- and 23-fold greater retinal uptake indexes (RUI) for [(3)H]β-alanine and [(3)H]l-histidine compared with that of a paracellular marker, respectively. The RUI of [(3)H]β-alanine was taurine- and γ-aminobutyric acid-sensitive, and the in vitro uptake by TR-iBRB2 cells showed time- concentration- and temperature-dependent [(3)H]β-alanine uptake, suggesting that a carrier-mediated process was involved in β-alanine transport across the inner BRB. [(3)H]β-Alanine uptake was inhibited by taurine and β-guanidinopropionic acid, suggesting that taurine transporter (TAUT/SLC6A6) is responsible for the influx transport of β-alanine across the inner BRB. Regarding l-histidine, the l-leucine-sensitive RUI of [(3)H]l-histidine was identified, and the in vitro [(3)H]l-histidine uptake by TR-iBRB2 cells suggested that a carrier-mediated process was involved in l-histidine transport across the inner BRB. The inhibition profile suggested that L-type amino acid transporter (LAT1/SLC7A5) is responsible for the influx transport of l-histidine across the inner BRB. These results show that the influx transports of β-alanine and l-histidine across the inner BRB is carried out by TAUT and LAT1, respectively, suggesting that the retinal l-carnosine is supplied by enzymatic synthesis from two kinds of amino acids transported across the inner BRB.

  1. Profiling clinical platelet and plasma use to inform blood supply and contingency planning: PUPPY, the prospective utilization of platelets and plasma study.

    Science.gov (United States)

    Fedele, Pasquale L; Polizzotto, Mark N; Grigoriadis, George; Waters, Neil; Comande, Mary; Borosak, Marija; Portbury, David; Wood, Erica M

    2016-10-01

    Demand for platelet (PLT) and plasma transfusions is increasing. Improved clinical supply and contingency planning requires greater understanding of usage profiles and urgency of clinical requirement. This study was a random-sample survey of PLT and plasma units produced in Victoria, Australia, to determine product disposition, recipient demographics, clinical indications for transfusion, and urgency (or "deferability") of need. PLTs and fresh-frozen plasma (FFP) were tagged with a case report form before distribution. A total of 1252 PLT and 1837 FFP units were tagged, comprising 8.3 and 13.3% of all products issued during the study period. The fate of 1243 PLT and 1808 FFP units was determined. Of products issued, 72.2% of PLTs and 87.8% of FFP were transfused. Hematologic and oncologic disorders accounted for 63.9% of PLT transfusions, with acute myeloid leukemia alone accounting for 26%. Conversely, surgical patients received the largest proportion of FFP (40.4%), predominantly for cardiothoracic, solid organ transplant, and vascular surgery. Approximately 15% of PLT transfusions and 35% of plasma transfusions were required within 1 hour, and 80% of PLT transfusions and 90% of FFP transfusions were required within 24 hours. Wastage rates were higher in regional blood banks. The PUPPY study is a comprehensive and detailed population-based assessment of PLT and plasma usage, including urgency of use. It identifies specific clinical areas with high demand for PLT and FFP transfusion and demonstrates the high urgency of need for both products. These data inform clinical supply and contingency planning activities. © 2016 AABB.

  2. Acute limb heating improves macro- and microvascular dilator function in the leg of aged humans.

    Science.gov (United States)

    Romero, Steven A; Gagnon, Daniel; Adams, Amy N; Cramer, Matthew N; Kouda, Ken; Crandall, Craig G

    2017-01-01

    Local heating of an extremity increases blood flow and vascular shear stress throughout the arterial tree. Local heating acutely improves macrovascular dilator function in the upper limbs of young healthy adults through a shear stress-dependent mechanism but has no such effect in the lower limbs of this age group. The effect of acute limb heating on dilator function within the atherosclerotic prone vasculature of the lower limbs of aged adults is unknown. Therefore, the purpose of this study was to test the hypothesis that acute lower limb heating improves macro- and microvascular dilator function within the leg vasculature of aged adults. Nine young and nine aged adults immersed their lower limbs at a depth of ~33 cm into a heated (~42°C) circulated water bath for 45 min. Before and 30 min after heating, macro (flow-mediated dilation)- and microvascular (reactive hyperemia) dilator functions were assessed in the lower limb, following 5 min of arterial occlusion, via Doppler ultrasound. Compared with preheat, macrovascular dilator function was unchanged following heating in young adults (P = 0.6) but was improved in aged adults (P = 0.04). Similarly, microvascular dilator function, as assessed by peak reactive hyperemia, was unchanged following heating in young adults (P = 0.1) but was improved in aged adults (P < 0.01). Taken together, these data suggest that acute lower limb heating improves both macro- and microvascular dilator function in an age dependent manner. We demonstrate that lower limb heating acutely improves macro- and microvascular dilator function within the atherosclerotic prone vasculature of the leg in aged adults. These findings provide evidence for a potential therapeutic use of chronic lower limb heating to improve vascular health in primary aging and various disease conditions. Copyright © 2017 the American Physiological Society.

  3. Applied anatomical study of blood supply in human palate%腭部血液供应的应用解剖学研究

    Institute of Scientific and Technical Information of China (English)

    仲维剑; 张奎启; 王福; 王宏青

    2001-01-01

    目的探讨腭部血管的来源、走行、分布,观察微血管系统的构筑形态。方法发育正常头部标本14例,腭裂标本10例,血管灌注后通过显微解剖、X线摄片、显微镜及扫描电镜观察分析。结果硬腭的血供主要来源于腭大动脉。小动脉分支呈“树枝状”,微动脉平行排列,毛细血管结构松散。腭升动脉是软腭的主要供血动脉。软腭的血管网可分为3层。小动脉分支角度多变,毛细血管网结构紧密。腭裂者血管来源与健康人相同,但走行、分布上有自身特点。结论软硬腭的血液供应分别来源于不同的动脉,血管网的构筑形态也各具特点。%Objective To investigate the origins and distributions of palatal vasculature and the three dimensional architecture. Methods Marterials consisted of 14 normal and 10 cleft palate head-and-neck specimens. After vascular infusion,specimens were seperately analysed by stereomicroscopy, radiography, histological study and scanning electron microscopy. Results The greater palatine artery was the main vessel to supply the hard palate and the ascending palatine artery provided the principal supply of soft palate. The branches of greater palatine artery formed abundant anastomoses with the neighbor vessels. The ascending palatine artery divided into two branches in the soft palate. The artery branches in hard palate took on tree-like appearance and were arranged parallel. The capillary network was loosely packed. Whereas,the arterys in soft palate were always found to be crooked. The angles of the branches from the main trunk were changeable. The capillary network was packed densely. The vascular origins and courses of the cleft palate specimens were the same as the normal person, but the distributions and anastomoses were different. Conclusions The blood supplies of hard and soft palate come from different vascular vessels and their vascular architectures have their own

  4. Fabrication, characterization, and modeling of microvascular composites

    Science.gov (United States)

    Ryan, Thomas J.

    Composite laminates of glass fiber and epoxy pre-preg were fabricated with microvascular channels. The channels were created using polylactic acid (PLA) filament that evaporates at a temperature of 392 °F (200 °C) above the resin cure temperature of 250 °F (121 °C). After the composite is cured, the panel was removed from the oven and allowed to cool to room temperature. The panel is then reheated to 392 °F to vaporize the filament, leaving a cylindrical channel. A microvascular channel can be used for withdrawing heat, damage detection and self-healing. However, increasing the temperatures of the laminate above the cure temperature of the resin causes excess cross linking, potentially decreasing the mechanical properties. Tensile and flexural mechanical tests were performed on composite specimens and tensile tests were performed on neat resin specimens. A three-dimensional finite element model (FEM) was developed to study the progressive deformation and damage mechanics under tensile loading. The load carrying capacity of the microvascular composite was shown to decrease by 40% from a standard composite material. This paper will present the details of the fabrication, characterization and modeling techniques that were used in this study.

  5. Microvascular structure as a prognostically relevant endpoint.

    Science.gov (United States)

    Agabiti-Rosei, Enrico; Rizzoni, Damiano

    2017-05-01

    Remodelling of subcutaneous small resistance arteries, as indicated by an increased media-to-lumen ratio, is frequently present in hypertensive, obese, or diabetic patients. The increased media-to-lumen ratio may impair organ flow reserve. This may be important in the maintenance and, probably, also in the progressive worsening of hypertensive disease. The presence of structural alterations represents a prognostically relevant factor, in terms of development of target organ damage or cardiovascular events, thus allowing us a prediction of complications in hypertension. In fact, media-to-lumen ratio of small arteries at baseline, and possibly their changes during treatment may have a strong prognostic significance. However, new, non-invasive techniques are needed before suggesting extensive application of the evaluation of remodelling of small arteries for the cardiovascular risk stratification in hypertensive patients. Some new techniques for the evaluation of microvascular morphology in the retina, currently under clinical investigation, seem to represent a promising and interesting future perspective. The evaluation of microvascular structure is progressively moving from bench to bedside, and it could represent, in the near future, an evaluation to be performed in all hypertensive patients, to obtain a better stratification of cardiovascular risk, and, possibly, it might be considered as an intermediate endpoint in the evaluation of the effects of antihypertensive therapy, provided that a demonstration of a prognostic value of non-invasive measures of microvascular structure is made available.

  6. Barrier stabilizing mediators in regulation of microvascular endothelial permeability

    Institute of Scientific and Technical Information of China (English)

    HUANG Qiao-bing

    2012-01-01

    Increase of microvascular permeability is one of the most important pathological events in the pathogenesis of trauma and bum injury.Massive leakage of fluid from vascular space leads to lose of blood plasma and decrease of effective circulatory blood volume,resulting in formation of severe tissue edema,hypotension or even shock,especially in severe bum injury.Fluid resuscitation has been the only valid approach to sustain patient's blood volume for a long time,due to the lack of overall and profound understanding of the mechanisms of vascular hyperpenneability response.There is an emerging concept in recent years that some so-called barrier stabilizing mediators play a positive role in preventing the increase of vascular permeability.These mediators may be released in response to proinflammatory mediators and serve to restore endothelial barrier function.Some of these stabilizing mediators are important even in quiescent state because they preserve basal vascular permeability at low levels.This review introduces some of these mediators and reveals their underlying signaling mechanisms during endothelial barrier enhancing process.

  7. Microvascular effects of copper deficiency in rats

    Energy Technology Data Exchange (ETDEWEB)

    Schuschke, D.A.; Saari, J.T.; Ackermann, D.M.; Miller, F.N. (Univ. of Louisville, KY (USA))

    1989-02-15

    We have studied the microcirculatory responses in copper deficient rats using the rat cremaster muscle preparation. Male Sprague-Dawley rats were fed either a copper supplemented diet (CuS, 5 ppm) or a copper deficient diet (CuD, O ppm) for five weeks prior to experimentation. The rats (240-300g) were anesthetized with pentobarbital and the cremaster (with intact nerve and blood supply) were spread in a tissue bath filled with krebs solution. In vivo television microscopy was used to observe the microcirculation. Fluorescein isothiocyanate tagged to bovine serum albumin (FITC-BSA) was injected i.a. 30 min prior to the start of experimentation. In the CuS animals photoactivation of the intravascular FITC-BSA caused significant platelet aggregation and reduction in red blood cell column diameter (RBCCD) by 30 min and stasis of flow by 60 min. In CuD animals there was no reduction in RBCCD and only minor platelet aggregation after 60 min of photoactivation. Topical administration of compound 48/80 (1.0 and 10.0 {mu}g/ml) induced a significantly greater macromolecular leakage (increased interstitial fluorescence of FITC-BSA) in the CuD animals than in the control, CuS animals. These results suggest that copper deficiency results in marked alterations of the regulatory mechanisms governing thrombosis and inflammation.

  8. Relationship between different subpopulations of circulating CD4+ T lymphocytes and microvascular or systemic oxidative stress in humans.

    Science.gov (United States)

    De Ciuceis, Carolina; Agabiti-Rosei, Claudia; Rossini, Claudia; Airò, Paolo; Scarsi, Mirko; Tincani, Angela; Tiberio, Guido Alberto Massimo; Piantoni, Silvia; Porteri, Enzo; Solaini, Leonardo; Duse, Sarah; Semeraro, Francesco; Petroboni, Beatrice; Mori, Luigi; Castellano, Maurizio; Gavazzi, Alice; Agabiti-Rosei, Enrico; Rizzoni, Damiano

    2017-08-01

    Different components of the immune system, including innate and adaptive immunity (T effector lymphocytes and T regulatory lymphocytes - TREGs) may be involved in the development of hypertension, vascular injury and inflammation. However, no data are presently available in humans about possible relationships between T-lymphocyte subtypes and microvascular oxidative stress. Our objective was to investigate possible relationships between T-lymphocyte subtypes and systemic and microvascular oxidative stress in a population of normotensive subjects and hypertensive patients. In the present study we enrolled 24 normotensive subjects and 12 hypertensive patients undergoing an elective surgical intervention. No sign of local or systemic inflammation was present. All patients underwent a biopsy of subcutaneous fat during surgery. A peripheral blood sample was obtained before surgery for assessment of T lymphocyte subpopulations by flow cytometry and circulating indices of oxidative stress. A significant direct correlation was observed between Th1 lymphocytes and reactive oxygen species (ROS) production (mainly in microvessels). Additionally, significant inverse correlations were observed between ROS and total TREGs, or TREGs subtypes. Significant correlations were detected between circulating indices of oxidative stress/inflammation and indices of microvascular morphology/Th1 and Th17 lymphocytes. In addition, a significant inverse correlation was detected between TREGs in subcutaneous small vessels and C reactive protein. Our data suggest that TREG lymphocytes may be protective against microvascular damage, probably because of their anti-oxidant properties, while Th1-Th17 lymphocytes seem to exert an opposite effect, confirming an involvement of adaptive immune system in microvascular damage.

  9. Microvascular system of anterior cruciate ligament in dogs.

    Science.gov (United States)

    Kobayashi, Shigeru; Baba, Hisatoshi; Uchida, Kenzo; Negoro, Kohei; Sato, Mituhiko; Miyazaki, Tsuyoshi; Nomura, Eiki; Murakami, Kaname; Shimizubata, Matsuyuki; Meir, Adam

    2006-07-01

    This study was done to investigate the microvascular system of anterior cruciate ligament (ACL) using dogs. The objective was to study the microvascular architecture and the status of the barrier function of the capillary wall in the ACL by using microangiogram, scanning (SEM), and transmission electron microscopy (TEM). The vascular system in the ACL has been intensively studied by a number of researchers, using several microangiographic techniques in dogs, rabbits, and humans. However, most of these microangiographic studies had significant shortcomings, including the lack of three-dimensional observations and function of the blood-joint barrier in the ACL. In this study, the microstructure of the ACL was examined using microangiogram, SEM, and TEM. We investigated the vasculature of the ACL with SEM of vascular corrosion casts. In addition, we examined the status of the barrier function of the capillary wall in the ACL using the protein tracer horseradish peroxidase (HRP). Feeding vessels of the ligament were predominantly coming from the synovial-derived vessels originating from the synovium attached to the ligament near the tibial and femoral bone insertions of the ACL. The anterior cruciate ligament was surrounded by synovium, which had abundant vessels. The branches of these synovial vessels were penetrating into the ligament and making the intrinsic vascular network. It was also ascertained under SEM that the perivascular space around the intrinsic vessels were communicating through the intrinsic ligament fiber bundles and the mesh-like synovial membrane. The capillaries in the ACL were all of the continuous type under TEM. The protein tracer that was injected into the joint space passed through the synovial membrane and entered into the capillary lumen in the ACL, but the tracer that was injected intravenously did not appear in the perivascular space. The existence of a blood-ACL barrier does not necessarily imply the existence of an ACL-blood barrier. We

  10. Microvascular reactivity during sympathetic stimulations in Raynaud's phenomenon.

    Science.gov (United States)

    Stoyneva, Zlatka B; Dermendjiev, Svetlan M; Medjidieva, Daniela G; Vodenicharov, Vlayko E

    2016-12-01

    The objective of the study was to assess skin autonomic microvascular reactivity to sympathetic stimulations and its association with primary and secondary Raynaud's phenomenon (RP). Laser-Doppler recorded finger pulp skin blood flow was monitored during orthostatic and deep breathing tests of 4 subjects groups, each of them composed of 20 subjects: group 1, healthy controls; group 2, vibration-induced secondary RP (vRP); group 3, primary RP (pRP); group 4, systemic sclerosis-related secondary RP (sclRP). Within groups comparisons by Wilcoxon matched pairs rank test and between groups by Bonferroni's multiple test for unpaired data were done using SPSS Statistics software. Reliably lower initial perfusion values were established in all the RP patients. The local sympathetic axon-reflex mediated responses to orthostasis were reduced in all RP groups with increased perfusions in upright posture instead of decreased. The vasoconstrictor responses to deep breathing tended to increase instead of decreasing in the vRP and pRP groups, while in the sclRP group the perfusions decreased. Strong correlations between the initial finger pulp perfusions and the orthostatic and deep breathing perfusion responses were found in the control, pRP and vRP groups (P<0.0001) and a modest correlation between the initial perfusions and the deep breathing perfusion responses in the sclRP group. Abnormal cutaneous microvascular reactivity to central and local axon-reflex sympathetic stimulations was established in RP patients reflecting self-regulatory dysfunctions which might contribute to the manifestations of the ischemic microcirculatory paroxysms. Laser Doppler flowmetry with functional orthostatic and deep breathing tests contribute to the diagnosis of RP.

  11. Changes of microvascular architecture, ultrastructure and permeability of rat jejunal villi at different ages

    Institute of Scientific and Technical Information of China (English)

    Yan-Min Chen; Jin-Sheng Zhang; Xiang-Lin Duan

    2003-01-01

    AIM: To investigate the changes of microvascular architecture, ultrastructure and permeability of rat jejunal villi at different ages.METHODS: Microvascular corrosion casting, scanning electron microscopy, transmission electron microscopy and Evans blue infiltration technique were used in this study.RESULTS: The intestinal villous plexus of adult rats consisted of arterioles, capillary network and venules. The marginal capillary extended to the base part of the villi and connected to the capillary networks of adjacent villi. In newborn rats,the villous plexus was rather simple, and capillary network was not formed. The villous plexus became cone-shaped and was closely arrayed in ablactation rats. In adult rats,the villous plexus became tongue-shaped and was enlarged both in height and width. In aged rats, the villous plexus shrank in volume and became shorter and narrower. The diametral ratio of villous arteriole to villous venule increased as animals became older. The number of endothelial holes,the thickness of basal membrane and the permeability of microvasculature were increased over the entire course of development from newborn period to aged period.CONCLUSION: The digestive and absorptive functions of the rat jejunum at different ages are highly dependent upon the state of villous microvascular architecture and permeability, and blood circulation is enhanced by collateral branches such as marginal capillary, through which blood is drained to the capillary networks of adjacent villi.

  12. Early systemic microvascular damage in pigs with atherogenic diabetes mellitus coincides with renal angiopoietin dysbalance

    NARCIS (Netherlands)

    M. Khairoun (Meriem); M.M. van den Heuvel (Mieke); B. van den Berg (Bernard); O. Sorop (Oana); De Boer, R. (Rients); N.S. van Ditzhuijzen (Nienke); I.M. Bajema (Ingeborg); H.J. Baelde; M. Zandbergen; D.J.G.M. Duncker (Dirk); T. Rabelink (Ton); M.E. Reinders (Marlies); W.J. van der Giessen (Wim); J.I. Rotmans (Joris)

    2015-01-01

    textabstractBackground: Diabetes mellitus (DM) is associated with a range of microvascular complications including diabetic nephropathy (DN). Microvascular abnormalities in the kidneys are common histopathologic findings in DN, which represent one manifestation of ongoing systemic microvascular dama

  13. Obesity, metabolic syndrome, impaired fasting glucose, and microvascular dysfunction: a principal component analysis approach

    Directory of Open Access Journals (Sweden)

    Panazzolo Diogo G

    2012-11-01

    Full Text Available Abstract Background We aimed to evaluate the multivariate association between functional microvascular variables and clinical-laboratorial-anthropometrical measurements. Methods Data from 189 female subjects (34.0±15.5 years, 30.5±7.1 kg/m2, who were non-smokers, non-regular drug users, without a history of diabetes and/or hypertension, were analyzed by principal component analysis (PCA. PCA is a classical multivariate exploratory tool because it highlights common variation between variables allowing inferences about possible biological meaning of associations between them, without pre-establishing cause-effect relationships. In total, 15 variables were used for PCA: body mass index (BMI, waist circumference, systolic and diastolic blood pressure (BP, fasting plasma glucose, levels of total cholesterol, high-density lipoprotein cholesterol (HDL-c, low-density lipoprotein cholesterol (LDL-c, triglycerides (TG, insulin, C-reactive protein (CRP, and functional microvascular variables measured by nailfold videocapillaroscopy. Nailfold videocapillaroscopy was used for direct visualization of nutritive capillaries, assessing functional capillary density, red blood cell velocity (RBCV at rest and peak after 1 min of arterial occlusion (RBCVmax, and the time taken to reach RBCVmax (TRBCVmax. Results A total of 35% of subjects had metabolic syndrome, 77% were overweight/obese, and 9.5% had impaired fasting glucose. PCA was able to recognize that functional microvascular variables and clinical-laboratorial-anthropometrical measurements had a similar variation. The first five principal components explained most of the intrinsic variation of the data. For example, principal component 1 was associated with BMI, waist circumference, systolic BP, diastolic BP, insulin, TG, CRP, and TRBCVmax varying in the same way. Principal component 1 also showed a strong association among HDL-c, RBCV, and RBCVmax, but in the opposite way. Principal component 3 was

  14. Strategic Supply

    Science.gov (United States)

    2003-01-01

    March 7, 2003. [29] Velis, Lil. “ Publishing Industry : Supply Chain Strategy in Action,” briefing presented to ICAF Strategic Supply Seminar, May 6...Lambert and Stock, page 48. [32] Velis, Lil. “ Publishing Industry : Supply Chain Strategy in Action,” briefing presented to ICAF Strategic Supply

  15. Perfusion MRI derived indices of microvascular shunting and flow control correlate with tumor grade and outcome in patients with cerebral glioma

    DEFF Research Database (Denmark)

    Tietze, Anna; Mouridsen, Kim; Lassen-Ramshad, Yasmin

    2015-01-01

    of microvascular flow control and the extent to which oxygen can be extracted by tumor tissue. The ability of these parameters and CBV to differentiate tumor grade were assessed by receiver operating characteristic curves and logistic regression. Their ability to predict time to progression and overall survival......Objectives: Deficient microvascular blood flow control is thought to cause tumor hypoxia and increase resistance to therapy. In glioma patients, we tested whether perfusion-weighted MRI (PWI) based indices of microvascular flow control provide more information on tumor grade and patient outcome...... than does the established PWI angiogenesis marker, cerebral blood volume (CBV). Material and Methods: Seventy-two glioma patients (sixty high-grade, twelve low-grade gliomas) were included. Capillary transit time heterogeneity (CTH) and COV, its ratio to blood mean transit time, provide indices...

  16. Transthoracic Doppler echocardiography compared with positron emission tomography for assessment of coronary microvascular dysfunction

    DEFF Research Database (Denmark)

    Michelsen, Marie Mide; Mygind, Naja Dam; Pena, Adam

    2017-01-01

    stenosis at invasive coronary angiography, TTDE CFVR by dipyridamole induced stress and MBFR by rubidium-82 PET with adenosine was successfully measured in 107 subjects. Repeatability of TTDE CFVR was assessed in 10 symptomatic women and in 10 healthy individuals. RESULTS: MBFR was systematically higher......BACKGROUND: Coronary microvascular function can be assessed by transthoracic Doppler echocardiography as a coronary flow velocity reserve (TTDE CFVR) and by positron emission tomography as a myocardial blood flow reserve (PET MBFR). PET MBFR is regarded the noninvasive reference standard...... for measuring coronary microvascular function but has limited availability. We compared TTDE CFVR with PET MBFR in women with angina pectoris and no obstructive coronary artery disease and assessed repeatability of TTDE CFVR. METHODS: From a cohort of women with angina and no obstructive coronary artery...

  17. Transcriptional network analysis for the regulation of left ventricular hypertrophy and microvascular remodeling.

    Science.gov (United States)

    Moreno-Moral, Aida; Mancini, Massimiliano; D'Amati, Giulia; Camici, Paolo; Petretto, Enrico

    2013-12-01

    Hypertension and cardiomyopathies share maladaptive changes of cardiac morphology, eventually leading to heart failure. These include left ventricular hypertrophy (LVH), myocardial fibrosis, and structural remodeling of coronary microcirculation, which is the morphologic hallmark of coronary microvascular dysfunction. To pinpoint the complex molecular mechanisms and pathways underlying LVH-associated cardiac remodeling independent of blood pressure effects, we employed gene network approaches to the rat heart. We used the Spontaneously Hypertensive Rat model showing many features of human hypertensive cardiomyopathy, for which we collected histological and histomorphometric data of the heart and coronary vasculature, and genome-wide cardiac gene expression. Here, we provide a large catalogue of gene co-expression networks in the heart that are significantly associated with quantitative variation in LVH, microvascular remodeling, and fibrosis-related traits. Many of these networks were significantly conserved to human idiopathic and/or ischemic cardiomyopathy patients, suggesting a potential role for these co-expressed genes in human heart disease.

  18. Blood-brain barrier permeability imaging using perfusion computed tomography

    Directory of Open Access Journals (Sweden)

    Avsenik Jernej

    2015-06-01

    Full Text Available Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with pathologies such as acute stroke, tumors, inflammatory and neurodegenerative diseases.

  19. Blood-brain barrier permeability imaging using perfusion computed tomography

    OpenAIRE

    Avsenik Jernej; Bisdas Sotirios; Popovic Katarina Surlan

    2015-01-01

    Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with patholog...

  20. Direct ink writing of microvascular networks

    Science.gov (United States)

    Wu, Willie

    Nature is replete with examples of embedded microvascular systems that enable efficient fluid flow and distribution for autonomic healing, cooling, and energy harvesting. The ability to incorporate microvascular networks in functional materials systems is therefore both scientifically and technologically important. In this PhD thesis, the direct-write assembly of planar and 3D biomimetic microvascular networks within polymer and hydrogel matrices is demonstrated. In addition, the influence of network design of fluid transport efficiency is characterized. Planar microvascular networks composed of periodic lattices of uniformal microchannels and hierarchical, branching architectures are constructed by direct-write assembly of a fugitive organic ink. Several advancements are required to facilitate their patterning, including pressure valving, dual ink printing, and dynamic pressure variation to allow tunable control of ink deposition. The hydraulic conductance is measured using a high pressure flow meter as a function of network design. For a constant vascular volume and areal coverage, 2- and 4-generation branched architectures that obey Murray's Law exhibited the highest hydraulic conductivity. These experimental observations are in good agreement with predictions made by analytic models. 3D microvascular networks are fabricated by omnidirectional printing a fugitive organic ink into a photopolymerizable hydrogel matrix that is capped with fluid filler of nearly identical composition. Using this approach, 3D networks of arbitrary design can be patterned. After ink deposition is complete, the matrix and fluid filler are chemically cross-linked via UV irradiation, and the ink is removed by liquefication. Aqueous solutions composed of a triblock copolymer of polyethylene oxide (PEO)-polypropylene oxide (PPO)-PEO constitute the materials system of choice due to their thermal- and concentration-dependent phase behavior. Specifically, the fugitive ink consists of a 23 w

  1. Diabetic microvascular complications: possible targets for improved macrovascular outcomes

    Directory of Open Access Journals (Sweden)

    Bijan Roshan

    2010-12-01

    Full Text Available John A D’Elia1, George Bayliss1,2, Bijan Roshan1, Manish Maski1, Ray E Gleason1, Larry A Weinrauch11Renal Unit, Joslin Diabetes Center, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; 2Department of Medicine, Rhode Island Hospital, Alpert School of Medicine, Brown University, Providence, RI, USAAbstract: The results of recent outcome trials challenge hypotheses that tight control of both glycohemoglobin and blood pressure diminishes macrovascular events and survival among type 2 diabetic patients. Relevant questions exist regarding the adequacy of glycohemoglobin alone as a measure of diabetes control. Are we ignoring mechanisms of vasculotoxicity (profibrosis, altered angiogenesis, hypertrophy, hyperplasia, and endothelial injury inherent in current antihyperglycemic medications? Is the polypharmacy for lowering cholesterol, triglyceride, glucose, and systolic blood pressure producing drug interactions that are too complex to be clinically identified? We review angiotensin–aldosterone mechanisms of tissue injury that magnify microvascular damage caused by hyperglycemia and hypertension. Many studies describe interruption of these mechanisms, without hemodynamic consequence, in the preservation of function in type 1 diabetes. Possible interactions between the renin–angiotensin–aldosterone system and physiologic glycemic control (through pulsatile insulin release suggest opportunities for further clinical investigation.Keywords: angiotensin-converting enzyme inhibitor, pulsatile insulin, diabetic nephropathy, cardiac autonomic neuropathy, podocytes, beta cells 

  2. 四川甘孜藏族自治州近五年采供血情况统计分析%Statistical Analysis of Blood Collection and Supply in Sichuan Ganzi Tibetan Autonomous Prefecture in Recent Five Years

    Institute of Scientific and Technical Information of China (English)

    李素英

    2016-01-01

    目的:分析研讨四川甘孜藏族自治州近五年采供血状况,并统计。方法将四川甘孜藏族自治州2011年1月至2015年12月期间血站采供血和医院用血数据统计作为分析研讨对象,统计此期间我地区采供血状况和临床使用状况,并分析。结果从统计五年内采供血状况上来看,2011年采血量和采血人次均位居首位,而2015年采血量和采血人次、其他医院供血量均位居第五,但总供血量、调血量、我院供血量等三者位居首位;五年间采血人次、采血量、总供血量、调血量、我院供血量、其他医院供血量方面,各年份间数据均有统计学意义(P<0.05)。结论近五年来,四川甘孜藏族自治州中心血站采血量逐年下降,但血液使用量呈逐年增加状况,出现严重的供需矛盾,血源长时间处于供不应求的状态,因此,建议政府相关部门对此加强重视度,并制定出相应有效措施进行干预,血站、医院可向社会做好献血宣传,提升人们献血意识和积极性,达到缓解临床用血紧张的状况,进而让更多生命得到成功救治。%Objective to analyze and study blood collection and supply situation in Ganzi Tibetan Autonomous Prefecture of Sichuan during the recent five years, and carry on statistics. Methods treat blood collection and supply and hospital blood data statistics of blood bank of Ganzi Tibetan Autonomous Prefecture of Sichuan from January 2011 to December 2015 as analysis and research objects, carry on statistics and analysis of blood collection and supply and clinical assumption status of the area during the period. Results statistics of blood collection and supply status during five years showed, blood collection volume and times in 2011 ranked the first, and in 2015 volume of times, blood supply of other hospitals ranked the fifth, but total blood supply volume, transfering volume, blood supply in our hospital

  3. Rapid homogeneous endothelialization of high aspect ratio microvascular networks.

    Science.gov (United States)

    Naik, Nisarga; Hanjaya-Putra, Donny; Haller, Carolyn A; Allen, Mark G; Chaikof, Elliot L

    2015-08-01

    Microvascularization of an engineered tissue construct is necessary to ensure the nourishment and viability of the hosted cells. Microvascular constructs can be created by seeding the luminal surfaces of microfluidic channel arrays with endothelial cells. However, in a conventional flow-based system, the uniformity of endothelialization of such an engineered microvascular network is constrained by mass transfer of the cells through high length-to-diameter (L/D) aspect ratio microchannels. Moreover, given the inherent limitations of the initial seeding process to generate a uniform cell coating, the large surface-area-to-volume ratio of microfluidic systems demands long culture periods for the formation of confluent cellular microconduits. In this report, we describe the design of polydimethylsiloxane (PDMS) and poly(glycerol sebacate) (PGS) microvascular constructs with reentrant microchannels that facilitates rapid, spatially homogeneous endothelial cell seeding of a high L/D (2 cm/35 μm; > 550:1) aspect ratio microchannels. MEMS technology was employed for the fabrication of a monolithic, elastomeric, reentrant microvascular construct. Isotropic etching and PDMS micromolding yielded a near-cylindrical microvascular channel array. A 'stretch - seed - seal' operation was implemented for uniform incorporation of endothelial cells along the entire microvascular area of the construct yielding endothelialized microvascular networks in less than 24 h. The feasibility of this endothelialization strategy and the uniformity of cellularization were established using confocal microscope imaging.

  4. Anatomy and clnical significance on blood supply of the subaxial vertebrae%下颈椎血供的解剖研究及其临床意义

    Institute of Scientific and Technical Information of China (English)

    林永绥; 王万明; 郑和平; 张发惠; 王春

    2012-01-01

    目的 为颈椎前路减压手术中减少出血量,改善显露和减少手术并发症的发生提供解剖学基础.方法 在15具成人尸体标本上,解剖观测C3~7椎体前后部血供的起源、走行、分支及吻合.结果 椎体前部血供来自颈升动脉脊支、甲状腺下动脉和颈深动脉脊支,C4~7椎前动脉在椎体上的分支相互吻合,在颈长肌的内侧缘处常吻合成一纵行动脉链;椎体后部血供来自椎间动脉发出的椎后动脉,其分支在颈椎体后部吻合形成节段性弧形动脉吻合链.结论 阻断术椎的椎前动脉及其与相邻椎前动脉的纵行动脉吻合,并在颈椎后部减压时注意对硬膜囊外侧缘及椎体中部处的椎后动脉及其分支的处理,可减少颈椎前路减压手术的术野出血,改善手术显露.%Objective To provide anatomic basis for reducing hemorrhage within operating field, improving operation exposure and reducing complication in cervical anterior decompression procedure through illuminating the feature of blood supply in subaxial cervical vertebrae. Methods The origin, course, distribution and anastomosis of anteroposterior blood supply were observed at C3-7 of IS adult cadaveric specimens perfused with red latex. Results Anterior cervical vertebral artery originated from spinal branches of ascending cervical artery, inferior thyroid artery and pinal branches of deep cervical artery. Its branches distributed at anterior cervical vertebrae, among which the branches at superior 1/3 segment of vertebrae were grossusest, and anastomosed with the branches in opposite side. The branches of anterior vertebral artery in C4-7 anastomosed with each other, and formed a longitudinal arterial chain at the medial margin of longus colli muscle. Posterior cervical vertebral artery originated from vertebral artery or ascending cervical and deep cervical arteries, and its branches sent out ascending and descending branches fairly at lateral border of

  5. Consistency and proportionality in policy decision-making in blood safety: the case for an all-apheresis platelet supply in Germany.

    Science.gov (United States)

    Vamvakas, E C; Hitzler, W E

    2013-01-01

    Recently, German investigators presented the first mathematical model finding a significant increase in the risk of HIV, HCV, and HBV transmission when pools of 4 whole-blood-derived buffy-coat platelets, rather than 1 single-donor (apheresis) component, are used to provide one platelet dose. Based, in both cases, on mathematical models employing the incidence/window-period method, the relative risk of transmission from pooled versus apheresis platelets (2.2 or 2.75 for HIV, 2.7 or 3.375 for HCV, and 3.2 or 4.0 for HBV, with pools of 4 or 5 concentrates, respectively) is similar to the difference in risk before (versus after) introduction of HIV-1 and HCV RNA screening. The absolute increase in the risk from pools (1 to 2 HIV-, HCV-, or HBV-infectious platelet doses annually) is much smaller than the yield from HIV-1 and HCV RNA screening projected in the 1990s, but it becomes similar to that yield (with up to 88 infectious platelet doses intercepted) when we consider the next transfusion-transmitted pathogen to emerge in the future. Although pathogen reduction (PR) of platelets would eliminate the difference in risk between pooled and apheresis platelets vis-a-vis viral transmission, PR is not ready for implementation because the safety of PR needs to be investigated further. German transfusion guidelines should be revised to indicate the difference in risk associated with pooled versus apheresis platelets, and transition toward an all-apheresis platelet supply should commence. These actions are consistent with and proportionate to the action taken in the 1990s when screening for HIV-1 and HCV RNA was implemented.

  6. Myocardial Microvascular Responsiveness During Acute Cardiac Sympathectomy Induced by Thoracic Epidural Anesthesia.

    Science.gov (United States)

    Bulte, Carolien S E; Boer, Christa; Hartemink, Koen J; Kamp, Otto; Heymans, Martijn W; Loer, Stephen A; de Marchi, Stefano F; Vogel, Rolf; Bouwman, R Arthur

    2017-02-01

    To evaluate the effect of acute cardiac sympathectomy by thoracic epidural anesthesia on myocardial blood flow and microvascular function. A prospective observational study. The study was conducted in a tertiary teaching hospital. Ten patients with a mean age of 48 years (range 22-63 years) scheduled for thoracic surgery. Myocardial contrast echocardiography was used to study myocardial blood flow and microvascular responsiveness at rest, during adenosine-induced hyperemia, and after sympathetic stimulation by the cold pressor test. Repeated measurements were performed without and with thoracic epidural anesthesia. An increased myocardial blood volume was observed with thoracic epidural anesthesia compared to baseline (from 0.08±0.02 to 0.10±0.03 mL/mL; p = 0.02). No difference existed in resting myocardial blood flow between baseline conditions and epidural anesthesia (0.85±0.24 v 1.03±0.27 mL/min/g, respectively). Hyperemia during thoracic epidural anesthesia increased myocardial blood flow to 4.31±1.07 mL/min/g (p = 0.0008 v baseline) and blood volume to 0.17±0.04 mL/mL (p = 0.005 baseline). After sympathetic stimulation, no difference in myocardial blood flow parameters was observed CONCLUSIONS: Acute cardiac sympathectomy by thoracic epidural anesthesia increased the blood volume in the myocardial capillary system. Also, thoracic epidural anesthesia increased hyperemic myocardial blood flow, indicating augmented endothelial-independent vasodilator capacity of the myocardium. Copyright © 2017. Published by Elsevier Inc.

  7. Transmural Variation and Anisotropy of Microvascular Flow Conductivity in the Rat Myocardium

    KAUST Repository

    Smith, Amy F.

    2014-05-28

    Transmural variations in the relationship between structural and fluid transport properties of myocardial capillary networks are determined via continuum modeling approaches using recent three-dimensional (3D) data on the microvascular structure. Specifically, the permeability tensor, which quantifies the inverse of the blood flow resistivity of the capillary network, is computed by volume-averaging flow solutions in synthetic networks with geometrical and topological properties derived from an anatomically-detailed microvascular data set extracted from the rat myocardium. Results show that the permeability is approximately ten times higher in the principal direction of capillary alignment (the "longitudinal" direction) than perpendicular to this direction, reflecting the strong anisotropy of the microvascular network. Additionally, a 30% increase in capillary diameter from subepicardium to subendocardium is shown to translate to a 130% transmural rise in permeability in the longitudinal capillary direction. This result supports the hypothesis that perfusion is preferentially facilitated during diastole in the subendocardial microvasculature to compensate for the severely-reduced systolic perfusion in the subendocardium.

  8. Comparison of Different Methods for the Calculation of the Microvascular Flow Index

    Directory of Open Access Journals (Sweden)

    Mario O. Pozo

    2012-01-01

    Full Text Available The microvascular flow index (MFI is commonly used to semiquantitatively characterize the velocity of microcirculatory perfusion as absent (0, intermittent (1, sluggish (2, or normal (3. There are three approaches to compute MFI: (1 the average of the predominant flow in each of the four quadrants (MFIby quadrants, (2 the direct assessment during the bedside video acquisition (MFIpoint of care, and (3 the mean value of the MFIs determined in each individual vessel (MFIvessel by vessel. We hypothesized that the agreement between the MFIs is poor and that the MFIvessel by vessel better reflects the microvascular perfusion. For this purpose, we analyzed 100 videos from septic patients. In 25 of them, red blood cell (RBC velocity was also measured. There were wide 95% limits of agreement between MFIby quadrants and MFIpoint of care (1.46, between MFIby quadrants and MFIvessel by vessel (2.85, and between MFIby point of care and MFIvessel by vessel (2.56. The MFIs significantly correlated with the RBC velocity and with the fraction of perfused small vessels, but MFIvessel by vessel showed the best R2. Although the different methods for the calculation of MFI reflect microvascular perfusion, they are not interchangeable and MFIvessel by vessel might be better.

  9. In vivo microvascular mosaics show air embolism reduction after perfluorocarbon emulsion treatment.

    Science.gov (United States)

    Torres Filho, Ivo P; Torres, Luciana N; Spiess, Bruce D

    2012-11-01

    Massive arteriolar gas embolism (AGE) has never been evaluated in vivo using intravital microscopy and previous perfluorocarbon (PFC) emulsions were only effective in AGE when administered before AGE. We implemented a new system for quantitative studies of massive AGE using brightfield microscopy and tested a treatment with a third-generation PFC emulsion after massive AGE. We studied bubble dynamics in cremaster muscles from anesthetized rats after AGE was induced by direct air injection into the femoral artery ipsilateral to the studied muscle. Using a motorized microscope stage and a color camera, in vivo microvascular mosaics were produced on-line from over 2000 digital images to evaluate multiple networks in order to investigate the distribution, lodging, breaking, reduction and moving of 105 air bubbles in microvessels. Thirty minutes after PFC treatment, there was a reduction of 80% in bubble volume while untreated and saline-treated rats showed significantly smaller decreases of 33% and 40%, respectively (pbubbles also dissolved into a larger number of smaller bubbles after PFC treatment. The proposed methodology may prove useful for rapid in vivo data acquisition from large networks. Since large air bubbles broke-up, decreased in length and volume, and moved toward smaller microvessels, the study provides quantitative data to support a mechanism by which PFC may improve tissue blood flow following massive AGE. The findings suggest that this new generation of PFC emulsions administered after severe AGE may reach compromised microvascular networks and provide help to alleviate microvascular obstruction by increasing air bubble reabsorption.

  10. Plasma soluble urokinase-type plasminogen activator receptor level is independently associated with coronary microvascular function in patients with non-obstructive coronary artery disease

    DEFF Research Database (Denmark)

    Mekonnen, Girum; Corban, Michel T; Hung, Olivia Y;

    2015-01-01

    , medications profiles and hs-CRP, suPAR remained an independent predictor of CFR (B = -0.30, p = 0.04), indicating an independent association between suPAR level and coronary microvascular function. CONCLUSIONS: In this cross-sectional study, plasma suPAR level was an independent predictor of coronary......BACKGROUND: Soluble urokinase-type plasminogen activator receptor (suPAR) is a novel biomarker released from leukocytes and endothelial cells that has been associated with atherosclerotic cardiovascular disease. We hypothesized that plasma suPAR level is an independent predictor of coronary...... microvascular function. METHODS: Coronary blood flow velocity and plasma suPAR levels were evaluated in patients with non-obstructive coronary artery disease. Coronary flow reserve (CFR) was calculated as the ratio of hyperemic to basal average peak blood flow velocity and coronary microvascular dysfunction...

  11. 股骨头血供:我国《外科学》教材之因袭及其商榷%Blood supply to the femoral head:discussion of textbook “Surgery”

    Institute of Scientific and Technical Information of China (English)

    梅炯

    2016-01-01

    Modern medicine textbooks first appeared in China at the end of the 19th century when Western missionaries initiated church medical schools in several Chinese cities. From early oral notes to the translation of Western medical books, Chinese medicine textbooks basically achieved localization in the 1960s after repeated practice and exploration. The content in the textbook “Surgery” has been substantially updated from the 1950’s trial version to the current eighth edition; however, that about the blood supply to the femoral head has been kept almost unchanged. The descriptions as well as the illustrations are almost the same in the first edition of the unified “Surgery” in 1979 to the eighth edition published in 2014. According to domestic and foreign research, content regarding the blood supply to the femoral head in Chinese surgical textbooks has not been properly updated and follows the literature from more than 60 years ago. In this paper, based on a review of the development of medicine textbooks, we compared the content about the blood supply to the femoral head in more than 10 versions of textbooks since the 1950 s, including the brief Soviet textbooks. It is suggested that the content about the blood supply to the femoral head in current textbooks should be updated and modified according to the latest research progress and the textbooks currently used in the United States. For example, the terminal branches of the medial and lateral femoral circumflex arteries should be termed as “retinacular arteries” as described in most modern literatures, rather than “lateral epiphysial artery”, “superior metaphysial artery”, and “inferior metaphyseal artery”.

  12. [The influence of the products prepared from young not ossified antlers marals of siberian red deer on the characteristics of the blood oxygen-supplying system in the athletes during the contest season].

    Science.gov (United States)

    Zaĭtsev, A A; Barabash, L V; Smirnova, I N; Abdulkina, N G; Kremeno, S V; Naumov, A O; Vereshchagina, S V; Shteĭnerdt, S V

    2012-01-01

    The objective of the present study was to estimate the influence of the products prepared from young not ossified antlers marals of Siberian red deer on the characteristics of the blood oxygen-supplying system in the athletes undergoing heavy physical loads during the contest season. It was shown that the use of such preparations promotes correction of humoral characteristics reflecting the development of iron-deficient conditions.

  13. Trigemino-cardiac reflex during microvascular trigeminal decompression in cases of trigeminal neuralgia.

    Science.gov (United States)

    Schaller, Bernhard

    2005-01-01

    The trigemino-cardiac reflex (TCR) is a well-recognized phenomenon consisting of bradycardia, arterial hypotension, apnea, and gastric hypermotility during ocular surgery or other manipulations in and around the orbit. Thus far, it could bee shown that central stimulation of the trigeminal nerve during transsphenoidal surgery and surgery for tumors in the cerebellopontine angle can lead to TCR. In cases of microvascular trigeminal decompression for trigeminal neuralgia, no data of the possible occurrence of TCR are available. TCR was defined as a drop in mean arterial blood pressure (MABP) and the heart rate (HR) of more than 20% to the baseline values before the stimulus and coinciding with the manipulation of the trigeminal nerve. Electronic anesthetic recorded perioperative HR and MABP values were reviewed retrospectively in 28 patients who received microvascular trigeminal decompression in cases of trigeminal neuralgia and were divided into two subgroups on the basis of occurrence of TCR during surgery. Of the 28 patients, 5 (18%) showed evidence of TCR during manipulation at the trigeminal radix by separation from microvascular structures. Their HR fell 46% and their MABP 57% during operative procedures near the trigeminal nerve as compared with levels immediately before the stimulus. After cessation of manipulation, HR and MABP returned (spontaneously) to levels before the stimulus. Risk factors of TCR were compared with results from the literature. In conclusion, the present results give evidence of TCR during manipulation of the central part of the trigeminal nerve during microvascular trigeminal decompression in cases of trigeminal neuralgia under a standardized anesthetic protocol.

  14. Molecular and cellular basis of microvascular perfusion deficits induced by Clostridium perfringens and Clostridium septicum.

    Directory of Open Access Journals (Sweden)

    Michael J Hickey

    2008-04-01

    Full Text Available Reduced tissue perfusion leading to tissue ischemia is a central component of the pathogenesis of myonecrosis caused by Clostridium perfringens. The C. perfringens alpha-toxin has been shown capable of inducing these changes, but its potential synergy with perfringolysin O (theta-toxin is less well understood. Similarly, Clostridium septicum is a highly virulent causative agent of spontaneous gas gangrene, but its effect on the microcirculation has not been examined. Therefore, the aim of this study was to use intravital microscopy to examine the effects of C. perfringens and C. septicum on the functional microcirculation, coupled with the use of isogenic toxin mutants to elucidate the role of particular toxins in the resultant microvascular perfusion deficits. This study represents the first time this integrated approach has been used in the analysis of the pathological response to clostridial toxins. Culture supernatants from wild-type C. perfringens induced extensive cell death within 30 min, as assessed by in vivo uptake of propidium iodide. Furthermore, significant reductions in capillary perfusion were observed within 60 min. Depletion of either platelets or neutrophils reduced the alteration in perfusion, consistent with a role for these blood-borne cells in obstructing perfusion. In addition, mutation of either the alpha-toxin or perfringolysin O structural genes attenuated the reduction in perfusion, a process that was reversed by genetic complementation. C. septicum also induced a marked reduction in perfusion, with the degree of microvascular compromise correlating with the level of the C. septicum alpha-toxin. Together, these data indicate that as a result of its ability to produce alpha-toxin and perfringolysin O, C. perfringens rapidly induces irreversible cellular injury and a marked reduction in microvascular perfusion. Since C. septicum induces a similar reduction in microvascular perfusion, it is postulated that this function

  15. Acute cocoa flavanol supplementation improves muscle macro- and microvascular but not anabolic responses to amino acids in older men.

    Science.gov (United States)

    Phillips, Bethan E; Atherton, Philip J; Varadhan, Krishna; Limb, Marie C; Williams, John P; Smith, Kenneth

    2016-05-01

    The anabolic effects of nutrition on skeletal muscle may depend on adequate skeletal muscle perfusion, which is impaired in older people. Cocoa flavanols have been shown to improve flow-mediated dilation, an established measure of endothelial function. However, their effect on muscle microvascular blood flow is currently unknown. Therefore, the objective of this study was to explore links between the consumption of cocoa flavanols, muscle microvascular blood flow, and muscle protein synthesis (MPS) in response to nutrition in older men. To achieve this objective, leg blood flow (LBF), muscle microvascular blood volume (MBV), and MPS were measured under postabsorptive and postprandial (intravenous Glamin (Fresenius Kabi, Germany), dextrose to sustain glucose ∼7.5 mmol·L(-1)) conditions in 20 older men. Ten of these men were studied with no cocoa flavanol intervention and a further 10 were studied with the addition of 350 mg of cocoa flavanols at the same time that nutrition began. Leg (femoral artery) blood flow was measured by Doppler ultrasound, muscle MBV by contrast-enhanced ultrasound using Definity (Lantheus Medical Imaging, Mass., USA) perflutren contrast agent and MPS using [1, 2-(13)C2]leucine tracer techniques. Our results show that although older individuals do not show an increase in LBF or MBV in response to feeding, these absent responses are apparent when cocoa flavanols are given acutely with nutrition. However, this restoration in vascular responsiveness is not associated with improved MPS responses to nutrition. We conclude that acute cocoa flavanol supplementation improves muscle macro- and microvascular responses to nutrition, independently of modifying muscle protein anabolism.

  16. Assessment of glycaemic, lipid and blood pressure control among ...

    African Journals Online (AJOL)

    Diabetes mellitus (DM) is a metabolic disorder primarily characterized by elevated blood glucose levels and microvascular andmacrovascular complications. ... are needed to reduce the likelihood of development of macrovascular disease.

  17. Liraglutide prevents microvascular insulin resistance and preserves muscle capillary density in high-fat diet-fed rats.

    Science.gov (United States)

    Chai, Weidong; Fu, Zhuo; Aylor, Kevin W; Barrett, Eugene J; Liu, Zhenqi

    2016-09-01

    Muscle microvasculature critically regulates endothelial exchange surface area to facilitate transendothelial delivery of insulin, nutrients, and oxygen to myocytes. Insulin resistance blunts insulin-mediated microvascular recruitment and decreases muscle capillary density; both contribute to lower microvascular blood volume. Glucagon-like peptide 1 (GLP-1) and its analogs are able to dilate blood vessels and stimulate endothelial cell proliferation. In this study, we aim to determine the effects of sustained stimulation of the GLP-1 receptors on insulin-mediated capillary recruitment and metabolic insulin responses, small arterial endothelial function, and muscle capillary density. Rats were fed a high-fat diet (HFD) for 4 wk with or without simultaneous administration of liraglutide and subjected to a euglycemic hyperinsulinemic clamp for 120 min after an overnight fast. Insulin-mediated muscle microvascular recruitment and muscle oxygenation were determined before and during insulin infusion. Muscle capillary density was determined and distal saphenous artery used for determination of endothelial function and insulin-mediated vasodilation. HFD induced muscle microvascular insulin resistance and small arterial vessel endothelial dysfunction and decreased muscle capillary density. Simultaneous treatment of HFD-fed rats with liraglutide prevented all of these changes and improved insulin-stimulated glucose disposal. These were associated with a significantly increased AMPK phosphorylation and the expressions of VEGF and its receptors. We conclude that GLP-1 receptor agonists may exert their salutary glycemic effect via improving microvascular insulin sensitivity and muscle capillary density during the development of insulin resistance, and early use of GLP-1 receptor agonists may attenuate metabolic insulin resistance as well as prevent cardiovascular complications of diabetes. Copyright © 2016 the American Physiological Society.

  18. A novel effective method for the assessment of microvascular function in male patients with coronary artery disease: a pilot study using laser speckle contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Borges, J.P. [Laboratório de Atividade Física e Promoção è Saúde, Departamento de Desporto Coletivo, Instituto de Educação Física e Desportos, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Lopes, G.O. [Laboratório de Atividade Física e Promoção è Saúde, Departamento de Desporto Coletivo, Instituto de Educação Física e Desportos, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Instituto Nacional de Cardiologia, Rio de Janeiro, RJ (Brazil); Verri, V.; Coelho, M.P.; Nascimento, P.M.C.; Kopiler, D.A. [Instituto Nacional de Cardiologia, Rio de Janeiro, RJ (Brazil); Tibirica, E. [Instituto Nacional de Cardiologia, Rio de Janeiro, RJ (Brazil); Laboratório de Investigação Cardiovascular, Departamento Osório de Almeida, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, RJ (Brazil)

    2016-09-01

    Evaluation of microvascular endothelial function is essential for investigating the pathophysiology and treatment of cardiovascular and metabolic diseases. Although laser speckle contrast imaging technology is well accepted as a noninvasive methodology for assessing microvascular endothelial function, it has never been used to compare male patients with coronary artery disease with male age-matched healthy controls. Thus, the aim of this study was to determine whether laser speckle contrast imaging could be used to detect differences in the systemic microvascular functions of patients with established cardiovascular disease (n=61) and healthy age-matched subjects (n=24). Cutaneous blood flow was assessed in the skin of the forearm using laser speckle contrast imaging coupled with the transdermal iontophoretic delivery of acetylcholine and post-occlusive reactive hyperemia. The maximum increase in skin blood flow induced by acetylcholine was significantly reduced in the cardiovascular disease patients compared with the control subjects (74 vs 116%; P<0.01). With regard to post-occlusive reactive hyperemia-induced vasodilation, the patients also presented reduced responses compared to the controls (0.42±0.15 vs 0.50±0.13 APU/mmHg; P=0.04). In conclusion, laser speckle contrast imaging can identify endothelial and microvascular dysfunctions in male individuals with cardiovascular disease. Thus, this technology appears to be an efficient non-invasive technique for evaluating systemic microvascular and endothelial functions, which could be valuable as a peripheral marker of atherothrombotic diseases in men.

  19. A novel effective method for the assessment of microvascular function in male patients with coronary artery disease: a pilot study using laser speckle contrast imaging

    Directory of Open Access Journals (Sweden)

    J.P. Borges

    2016-01-01

    Full Text Available Evaluation of microvascular endothelial function is essential for investigating the pathophysiology and treatment of cardiovascular and metabolic diseases. Although laser speckle contrast imaging technology is well accepted as a noninvasive methodology for assessing microvascular endothelial function, it has never been used to compare male patients with coronary artery disease with male age-matched healthy controls. Thus, the aim of this study was to determine whether laser speckle contrast imaging could be used to detect differences in the systemic microvascular functions of patients with established cardiovascular disease (n=61 and healthy age-matched subjects (n=24. Cutaneous blood flow was assessed in the skin of the forearm using laser speckle contrast imaging coupled with the transdermal iontophoretic delivery of acetylcholine and post-occlusive reactive hyperemia. The maximum increase in skin blood flow induced by acetylcholine was significantly reduced in the cardiovascular disease patients compared with the control subjects (74 vs 116%; P<0.01. With regard to post-occlusive reactive hyperemia-induced vasodilation, the patients also presented reduced responses compared to the controls (0.42±0.15 vs 0.50±0.13 APU/mmHg; P=0.04. In conclusion, laser speckle contrast imaging can identify endothelial and microvascular dysfunctions in male individuals with cardiovascular disease. Thus, this technology appears to be an efficient non-invasive technique for evaluating systemic microvascular and endothelial functions, which could be valuable as a peripheral marker of atherothrombotic diseases in men.

  20. A novel effective method for the assessment of microvascular function in male patients with coronary artery disease: a pilot study using laser speckle contrast imaging.

    Science.gov (United States)

    Borges, J P; Lopes, G O; Verri, V; Coelho, M P; Nascimento, P M C; Kopiler, D A; Tibirica, E

    2016-09-01

    Evaluation of microvascular endothelial function is essential for investigating the pathophysiology and treatment of cardiovascular and metabolic diseases. Although laser speckle contrast imaging technology is well accepted as a noninvasive methodology for assessing microvascular endothelial function, it has never been used to compare male patients with coronary artery disease with male age-matched healthy controls. Thus, the aim of this study was to determine whether laser speckle contrast imaging could be used to detect differences in the systemic microvascular functions of patients with established cardiovascular disease (n=61) and healthy age-matched subjects (n=24). Cutaneous blood flow was assessed in the skin of the forearm using laser speckle contrast imaging coupled with the transdermal iontophoretic delivery of acetylcholine and post-occlusive reactive hyperemia. The maximum increase in skin blood flow induced by acetylcholine was significantly reduced in the cardiovascular disease patients compared with the control subjects (74 vs 116%; PAPU/mmHg; P=0.04). In conclusion, laser speckle contrast imaging can identify endothelial and microvascular dysfunctions in male individuals with cardiovascular disease. Thus, this technology appears to be an efficient non-invasive technique for evaluating systemic microvascular and endothelial functions, which could be valuable as a peripheral marker of atherothrombotic diseases in men.

  1. Differentiation state determines neural effects on microvascular endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Muffley, Lara A., E-mail: muffley@u.washington.edu [University of Washington, Campus Box 359796, 300 9th Avenue, Seattle, WA 98104 (United States); Pan, Shin-Chen, E-mail: pansc@mail.ncku.edu.tw [University of Washington, Campus Box 359796, 300 9th Avenue, Seattle, WA 98104 (United States); Smith, Andria N., E-mail: gnaunderwater@gmail.com [University of Washington, Campus Box 359796, 300 9th Avenue, Seattle, WA 98104 (United States); Ga, Maricar, E-mail: marga16@uw.edu [University of Washington, Campus Box 359796, 300 9th Avenue, Seattle, WA 98104 (United States); Hocking, Anne M., E-mail: ahocking@u.washington.edu [University of Washington, Campus Box 359796, 300 9th Avenue, Seattle, WA 98104 (United States); Gibran, Nicole S., E-mail: nicoleg@u.washington.edu [University of Washington, Campus Box 359796, 300 9th Avenue, Seattle, WA 98104 (United States)

    2012-10-01

    Growing evidence indicates that nerves and capillaries interact paracrinely in uninjured skin and cutaneous wounds. Although mature neurons are the predominant neural cell in the skin, neural progenitor cells have also been detected in uninjured adult skin. The aim of this study was to characterize differential paracrine effects of neural progenitor cells and mature sensory neurons on dermal microvascular endothelial cells. Our results suggest that neural progenitor cells and mature sensory neurons have unique secretory profiles and distinct effects on dermal microvascular endothelial cell proliferation, migration, and nitric oxide production. Neural progenitor cells and dorsal root ganglion neurons secrete different proteins related to angiogenesis. Specific to neural progenitor cells were dipeptidyl peptidase-4, IGFBP-2, pentraxin-3, serpin f1, TIMP-1, TIMP-4 and VEGF. In contrast, endostatin, FGF-1, MCP-1 and thrombospondin-2 were specific to dorsal root ganglion neurons. Microvascular endothelial cell proliferation was inhibited by dorsal root ganglion neurons but unaffected by neural progenitor cells. In contrast, microvascular endothelial cell migration in a scratch wound assay was inhibited by neural progenitor cells and unaffected by dorsal root ganglion neurons. In addition, nitric oxide production by microvascular endothelial cells was increased by dorsal root ganglion neurons but unaffected by neural progenitor cells. -- Highlights: Black-Right-Pointing-Pointer Dorsal root ganglion neurons, not neural progenitor cells, regulate microvascular endothelial cell proliferation. Black-Right-Pointing-Pointer Neural progenitor cells, not dorsal root ganglion neurons, regulate microvascular endothelial cell migration. Black-Right-Pointing-Pointer Neural progenitor cells and dorsal root ganglion neurons do not effect microvascular endothelial tube formation. Black-Right-Pointing-Pointer Dorsal root ganglion neurons, not neural progenitor cells, regulate

  2. Microvascular network topology of the human retinal vessels.

    Science.gov (United States)

    Schröder, S; Brab, M; Schmid-Schönbein, G W; Reim, M; Schmid-Schönbein, H

    1990-01-01

    A quantitative analysis of blood flow in the human retinal vessels requires a detailed picture of the microvascular network topology. In order to lay the foundation for a quantitative microcirculatory network analysis of the human retina, a novel technique for tissue preparation and network characterization was developed. After injection of hydrogen peroxide into the human bulb, the microvasculature was filled with oxygen produced by endothelial catalase and visualized after embedding in a mixture of cedar oil and gum damar. The vessel topology was documented in the form of photomicrographs, which permitted complete reconstruction of the microvasculature on transparent overlays. By considering the complete capillary system it was possible to divide the retinal network into dichotomous, asymmetric arteriolar and venular trees. The Strahler ordering method, which considers both dichotomous and side branching configurations, was selected and applied to analyze the retinal vascular trees, using the capillaries as the zero order reference vessels. The number of vessel segments was found to be an approximate logarithmic function of the order number, in accordance with Horton's law. Vessel lengths within each order were found to be log-normal distributed, and median lengths for different orders could be approximated by a 2nd degree polynomial curve. Diameters within each order could be approximated by a Gaussian distribution, and the mean values for different orders could be expressed by an exponential curve. These data provide the basis for conductance, pressure and flow computations within the retinal microvessels.

  3. Self-healing materials with microvascular networks.

    Science.gov (United States)

    Toohey, Kathleen S; Sottos, Nancy R; Lewis, Jennifer A; Moore, Jeffrey S; White, Scott R

    2007-08-01

    Self-healing polymers composed of microencapsulated healing agents exhibit remarkable mechanical performance and regenerative ability, but are limited to autonomic repair of a single damage event in a given location. Self-healing is triggered by crack-induced rupture of the embedded capsules; thus, once a localized region is depleted of healing agent, further repair is precluded. Re-mendable polymers can achieve multiple healing cycles, but require external intervention in the form of heat treatment and applied pressure. Here, we report a self-healing system capable of autonomously repairing repeated damage events. Our bio-inspired coating-substrate design delivers healing agent to cracks in a polymer coating via a three-dimensional microvascular network embedded in the substrate. Crack damage in the epoxy coating is healed repeatedly. This approach opens new avenues for continuous delivery of healing agents for self-repair as well as other active species for additional functionality.

  4. Phase transition of the microvascular network architecture in human pathologies.

    Science.gov (United States)

    Bianciardi, Giorgio; Traversi, Claudio; Cattaneo, Ruggero; De Felice, Claudia; Monaco, Annalisa; Tosi, Gianmarco; Parrini, Stefano; Latini, Giuseppe

    2012-01-01

    We have investigated the microvascular pattern in acquired or genetic diseases in humans. The lower gingival and vestibular oral mucosa, as well as the optic nerve head, was chosen to characterize the vascular pattern complexity due to the simple accessibility and visibility Local fractal dimensions, fractal dimension of the minimum path and Lempel-Ziv complexity have been used as operational numerical tools to characterize the microvascular networks. In the normal healthy subjects microvascular networks show nonlinear values corresponding to the complexity of a diffusion limited aggregation (DLA) model, while in several acquired or genetic diseases they are approaching the ones of an invasion percolation model.

  5. Association of Microvascular Dysfunction With Late-Life Depression

    DEFF Research Database (Denmark)

    van Agtmaal, Marnix J M; Houben, Alfons J H M; Pouwer, Frans

    2017-01-01

    Importance: The etiologic factors of late-life depression are still poorly understood. Recent evidence suggests that microvascular dysfunction is associated with depression, which may have implications for prevention and treatment. However, this association has not been systematically reviewed...... microvascular dysfunction might provide a potential target for the prevention and treatment of depression........ Objective: To examine the associations of peripheral and cerebral microvascular dysfunction with late-life depression. Data Sources: A systematic literature search was conducted in MEDLINE and EMBASE for and longitudinal studies published since inception to October 16, 2016, that assessed the associations...

  6. Microvascular pressure distribution in the hamster testis.

    Science.gov (United States)

    Sweeney, T E; Rozum, J S; Desjardins, C; Gore, R W

    1991-05-01

    Convective transport is a critical element in the regulation of steroidogenesis and spermatogenesis in the testis. Steroid hormones are distributed to their target cells within seminiferous tubules via interstitial fluid. The movement of interstitial fluid and lymph, which transports protein hormones and many of the substrates required for spermatogenesis and steroidogenesis, is driven by capillary filtration. Despite the importance of convective transport in testicular function, however, the mechanisms regulating transvascular exchange in the testis are unknown. As a first step in understanding this process, we measured directly the microvascular hydrostatic pressure distribution in the hamster testis (pentobarbital sodium, 70 mg/kg ip). Using a servo-null transducer, intravascular pressure was measured in all vessel types accessible beneath the surface of the testis of 19 animals. Systemic arterial pressure averaged 89 +/- 2 (SE) mmHg. The most significant observations were that mean capillary pressure was extremely low (10.1 +/- 0.8 mmHg) and remarkably constant (range 8.2-13.3 mmHg), despite a 45 mmHg range in systemic mean arterial pressure among the animals observed. The maintenance of a low hydrostatic pressure in testicular capillaries may serve to sustain fluid filtration at a rate that prevents washout of essential solutes while preserving convective transport. Unfortunately, the anatomical and functional characteristics that determine this unique microvascular environment may also expose the testis to significant pathological risks. For example, the large pre- to postcapillary resistance ratio observed suggests that testicular capillaries must be highly susceptible to increases in venous pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Mandibular reconstruction with composite microvascular tissue transfer

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, J.J. III; Wooden, W.A. (Emory Univ. School of Medicine, Atlanta, GA (USA))

    1990-10-01

    Microvascular free tissue transfer has provided a variety of methods of restoring vascularized bone and soft tissue to difficult defects created by tumor resection and trauma. Over 7 years, 26 patients have undergone 28 free flaps for mandibular reconstruction, 15 for primary squamous cell carcinoma of the floor of the mouth or tongue, 7 for recurrent tumor, and 6 for other reasons (lymphangioma (1), infection (1), gunshot wound (1), and osteoradionecrosis (3)). Primary reconstruction was performed in 19 cases and secondary in 9. All repairs were composite flaps including 12 scapula, 5 radial forearm, 3 fibula, 2 serratus, and 6 deep circumflex iliac artery. Mandibular defects included the symphysis alone (7), symphysis and body (5), symphysis-body-ramus condyle (2), body or ramus (13), and bilateral body (1). Fourteen patients had received prior radiotherapy to adjuvant or curative doses. Eight received postoperative radiotherapy. All patients had initially successful vascularized reconstruction by clinical examination (28) and positive radionuclide scan (22 of 22). Bony stability was achieved in 25 of 26 patients and oral continence in 24 of 26. One complete flap loss occurred at 14 days. Complications of some degree developed in 22 patients including partial skin necrosis (3), orocutaneous fistula (3), plate exposure (1), donor site infection (3), fracture of reconstruction (1), and fracture of the radius (1). Microvascular transfer of bone and soft tissue allows a reliable reconstruction--despite previous radiotherapy, infection, foreign body, or surgery--in almost every situation in which mandible and soft tissue are absent. Bony union, a healed wound, and reasonable function and appearance are likely despite early fistula, skin loss, or metal plate or bone exposure.

  8. 冠心病稳定性心绞痛与微血管性心绞痛中医证候要素调查%Expert Investigation of Traditional Chinese Medical Syndrome Elements of Microvascular Angina Pectoris and Stable Angina Pectoris Induced by Coronary Artery Disease

    Institute of Scientific and Technical Information of China (English)

    毕颖斐; 毛静远

    2012-01-01

    [目的]对冠心病稳定性心绞痛与微血管性心绞痛的中医证候要素进行专家调查.[方法]运用专家调查( Delphi)法在全国范围内对冠心病稳定性心绞痛与微血管性心绞痛的中医证候要素及证候类型进行专家咨询和调查.[结果]冠心病稳定性心绞痛与微血管性心绞痛的中医证候要素及证候类型分布基本一致,但也存在一定差异,微血管性心绞痛较稳定性心绞痛多见气滞、血虚等证素及气滞心胸证.[结论]本调查结果可为冠心病稳定性心绞痛与微血管性心绞痛的中医临床辨证提供一定的参考.%Objective To investigate the traditional Chinese medical syndrome elements of microvascular angina pectoris and stable angina pectoris induced by coronary artery disease. Methods Delphi method was adopted for the investigation of traditional Chinese medical syndrome elements and syndrome patterns of microvascular angina pectoris and stable angina pectoris induced by coronary artery disease by experts overall the country. Results Syndrome elements and syndrome patterns were similar in patients with microvascular angina pectoris and stable angina pectoris induced by coronary artery disease. However, some differences existed in the two kinds of angina pectoris, microvascular angina pectoris patients were characterized with syndrome elements of Qi stagnation and blood deficiency, and with syndrome pattern of Qi stagnation in heart and chest. Conclusion The results of the investigation will supply certain evidence for syndrome differentiation of microvascular angina pectoris and stable angina pectoris induced by coronary artery disease.

  9. 扩张皮瓣转移术后血运障碍的原因分析与处理%The cause and management of the disorder of blood supplying of expanded flaps after reconstruction

    Institute of Scientific and Technical Information of China (English)

    薛文丽; 宋维铭; 王佳琦; 王千文; 郑行跃; 侯典举; 郭鑫; 于浩; 王太玲

    2013-01-01

    Objective To investigate the cause and management of the disorder of blood supplying of expanded flaps after reconstruction.Methods Totally 325 patients with 903 expanded flaps were reviewed retrospectively for the disorder of blood supplying.The data concerned were analysed statistically, and the therapeutic methods were also summarized.Results The number of disorder of blood supplying of the expanded flaps: total 43 (4.76% ) , upper limbs 11, trunk 12, neck 8, lower limbs 1, head and face 11, local skin flap 28 , ortho-position skin flap 7, distant skin flap 8.The cause of the disorder of blood supplying of expanded flaps: large length to width ratio 12, thin of expanded flap in central part 7, hematoma 8 , infection 4, large of flap tension 4, containing scar tissue in expanded flap 5, removal of envelope 3.Conclusion There is a significant relationship between the disorder of blood supplying of expanded flaps and expanded positions.There is also a significant relationship between the disorder of blood supplying of expanded flaps and the pattern of expanded flaps.The local skin flaps have lower incidences of disorder of blood supplying than the ortho-position and distant skin flaps.As to the distant and ortho-position skin flaps with large length to width ratio, the flap delaying operation can improve the survival of the expanded skin flap.%目的 探讨扩张皮瓣转移术后血运障碍的原因及预防处理的措施.方法 对采用扩张皮瓣转移修复治疗的325例患者、903个扩张皮瓣进行回顾性研究,将相关数据进行统计学分析并对其处理方法进行总结.结果 扩张皮瓣发生血运障碍者43例(4.76%);发生部位:上肢11例、躯干部12例、颈部8例、下肢1例、头面部11例.采用局部皮瓣修复28例,邻位皮瓣修复7例,远位皮瓣修复8例.扩张皮瓣发生血运障碍的原因:皮瓣长宽比例过大12例、皮瓣中央过薄7例、血肿8例、感染4例、皮瓣张力过大4

  10. Analysis of Clinical Blood Collection and Supply from 2012 to 2015 in Fuyang City%阜阳市2012~2015年采供血情况分析

    Institute of Scientific and Technical Information of China (English)

    沈小婷; 操基玉; 姚全邦

    2016-01-01

    目的:探讨如何合理用血、缓解临床用血供需矛盾、杜绝血液浪费、保证血液安全有效、解决临床用血可持续发展的采供血新模式。方法对阜阳市中心血站2012~2015年采供血数据进行统计学分析。结果总采血量呈逐年下降趋势,红细胞和冷沉淀用量增加,成分用血比例提升到98.5%。外调血主要包括红细胞、血浆和单采血小板,其中以红细胞量最多、单采血小板量最少。不同年份分析,以2012年度最高、2015年度最低。结论随着医疗水平的发展和临床输血技术的规范,阜阳市临床合理用血水平明显提升;探寻适宜的无偿献血宣传、招募模式,加强农村无偿献血宣传、招募,制定科学合理的采供血计划,对阜阳市无偿献血事业的健康发展具有非常重要的意义。%Objective To discuss on how to use blood reasonably and alleviate the contradiction between supply and demand of clinical blood use, putting an end to waste of blood, guaranteeing the safe, timely and effective clinical use of blood in a sustainable mode. Methods Making statistical analysis of Fuyang city center blood stations during 2012 to 2015, the data includes collcetion and supply. Results The total HP has a downward trend year by year, the dosage level of red blood cells and cryoprecipitate increased, the using scale of blood component increased with its ratio grew to 98.5%. The transfer of blood mainly included red blood cells, plasma and platelets, red blood cells and platelet shared the most and the least amount respectively. When considering different years, 2012 peaked and 2015 bottomed. Conclusion With the improvement of medical level and technical specifications of clinical blood transfusion, reasonable level improved significantly with blood usage. Scientific and reasonable planning of blood sampling and supply has shown great significance, including exploring diversified publicity of blood

  11. Obesity is associated with lower coronary microvascular density.

    Directory of Open Access Journals (Sweden)

    Duncan J Campbell

    Full Text Available BACKGROUND: Obesity is associated with diastolic dysfunction, lower maximal myocardial blood flow, impaired myocardial metabolism and increased risk of heart failure. We examined the association between obesity, left ventricular filling pressure and myocardial structure. METHODS: We performed histological analysis of non-ischemic myocardium from 57 patients (46 men and 11 women undergoing coronary artery bypass graft surgery who did not have previous cardiac surgery, myocardial infarction, heart failure, atrial fibrillation or loop diuretic therapy. RESULTS: Non-obese (body mass index, BMI, ≤ 30 kg/m(2, n=33 and obese patients (BMI >30 kg/m(2, n=24 did not differ with respect to myocardial total, interstitial or perivascular fibrosis, arteriolar dimensions, or cardiomyocyte width. Obese patients had lower capillary length density (1145 ± 239, mean ± SD, vs. 1371 ± 333 mm/mm(3, P=0.007 and higher diffusion radius (16.9 ± 1.5 vs. 15.6 ± 2.0 μm, P=0.012, in comparison with non-obese patients. However, the diffusion radius/cardiomyocyte width ratio of obese patients (0.73 ± 0.11 μm/μm was not significantly different from that of non-obese patients (0.71 ± 0.11 μm/μm, suggesting that differences in cardiomyocyte width explained in part the differences in capillary length density and diffusion radius between non-obese and obese patients. Increased BMI was associated with increased pulmonary capillary wedge pressure (PCWP, P<0.0001, and lower capillary length density was associated with both increased BMI (P=0.043 and increased PCWP (P=0.016. CONCLUSIONS: Obesity and its accompanying increase in left ventricular filling pressure were associated with lower coronary microvascular density, which may contribute to the lower maximal myocardial blood flow, impaired myocardial metabolism, diastolic dysfunction and higher risk of heart failure in obese individuals.

  12. Clinical outcome following micro-vascular decompression for trigeminal neuralgia

    Directory of Open Access Journals (Sweden)

    Godugu Bhaskar Rao

    2015-07-01

    Conclusion: Micro-vascular decompression is safe and effective in producing good pain relief over a long term in patients with Trigeminal neuralgias refractive to medical treatment. [Int J Res Med Sci 2015; 3(7.000: 1741-1744

  13. Retinal microvascular abnormalities and stroke: a systematic review

    NARCIS (Netherlands)

    Doubal, F.N.; Hokke, P.E.; Wardlaw, J.M.

    2009-01-01

    Background: Lacunar strokes account for 25% of ischaemic strokes, but their precise aetiology is unknown. Similarities between the retinal and cerebral small vessels mean that clarification of the exact relationship between retinal microvascular abnormalities and stroke, and particularly with stroke

  14. Deleterious Effects of Intra-arterial Administration of Particulate Steroids on Microvascular Perfusion in a Mouse Model.

    Science.gov (United States)

    Laemmel, Elisabeth; Segal, Nicolas; Mirshahi, Massoud; Azzazene, Dalel; Le Marchand, Sylvie; Wybier, Marc; Vicaut, Eric; Laredo, Jean-Denis

    2016-06-01

    Purpose To determine the in vivo effects of several particulate steroids on microvascular perfusion by using intravital microscopy in a mice model and to investigate the in vitro interactions between these particulate steroids and red blood cells (RBCs). Materials and Methods The study was conducted in agreement with the guidelines of the National Committee of Ethic Reflection on Animal Experimentation. By using intravital microscopy of mouse cremaster muscle, the in vivo effects of several particulate steroids on microvascular perfusion were assessed. Four to five mice were allocated to each of the following treatment groups: saline solution, dexamethasone sodium phosphate, a nonparticulate steroid, and the particulate steroids cortivazol, methylprednisolone, triamcinolone, and prednisolone. By using in vitro blood microcinematography and electron microscopy, the interactions between these steroids and human RBCs were studied. All results were analyzed by using nonparametric tests. Results With prednisolone, methylprednisolone, or triamcinolone, blood flow was rapidly and completely stopped in all the arterioles and venules (median RBC velocity in first-order arterioles, 5 minutes after administration was zero for these three groups) compared with a limited effect in mice treated with saline, dexamethasone, and cortivazol (20.3, 21.3, and 27.5 mm/sec, respectively; P steroids. Conclusion Several particulate steroids have an immediate and massive effect on microvascular perfusion because of formation of RBC aggregates associated with the transformation of RBCs into spiculated RBCs. (©) RSNA, 2016 Online supplemental material is available for this article.

  15. Microvascular permeability changes might explain cardiac tamponade after alcohol septal ablation for hypertrophic cardiomyopathy.

    Science.gov (United States)

    Hsu, Jen-Te; Hsiao, Ju-Feng; Chang, Jung-Jung; Chung, Chang-Min; Chang, Shih-Tai; Pan, Kuo-Li

    2014-04-01

    Various sequelae of alcohol septal ablation for hypertrophic obstructive cardiomyopathy have been reported. Of note, some cases of cardiac tamponade after alcohol septal ablation cannot be well explained. We describe the case of a 78-year-old woman with hypertrophic obstructive cardiomyopathy in whom cardiac tamponade developed one hour after alcohol septal ablation, probably unrelated to mechanical trauma. At that time, we noted a substantial difference in the red blood cell-to-white blood cell ratio between the pericardial effusion (1,957.4) and the peripheral blood (728.3). In addition to presenting the patient's case, we speculate that a possible mechanism for acute tamponade--alcohol-induced changes in microvascular permeability--is a reasonable explanation for cases of alcohol septal ablation that are complicated by otherwise-unexplainable massive pericardial effusions.

  16. Novel biomarkers of arterial and venous ischemia in microvascular flaps.

    Directory of Open Access Journals (Sweden)

    Gerard K Nguyen

    Full Text Available The field of reconstructive microsurgery is experiencing tremendous growth, as evidenced by recent advances in face and hand transplantation, lower limb salvage after trauma, and breast reconstruction. Common to all of these procedures is the creation of a nutrient vascular supply by microsurgical anastomosis between a single artery and vein. Complications related to occluded arterial inflow and obstructed venous outflow are not uncommon, and can result in irreversible tissue injury, necrosis, and flap loss. At times, these complications are challenging to clinically determine. Since early intervention with return to the operating room to re-establish arterial inflow or venous outflow is key to flap salvage, the accurate diagnosis of early stage complications is essential. To date, there are no biochemical markers or serum assays that can predict these complications. In this study, we utilized a rat model of flap ischemia in order to identify the transcriptional signatures of venous congestion and arterial ischemia. We found that the critical ischemia time for the superficial inferior epigastric fasciocutaneus flap was four hours and therefore performed detailed analyses at this time point. Histolgical analysis confirmed significant differences between arterial and venous ischemia. The transcriptome of ischemic, congested, and control flap tissues was deciphered by performing Affymetrix microarray analysis and verified by qRT-PCR. Principal component analysis revealed that arterial ischemia and venous congestion were characterized by distinct transcriptomes. Arterial ischemia and venous congestion was characterized by 408 and 1536>2-fold differentially expressed genes, respectively. qRT-PCR was used to identify five candidate genes Prol1, Muc1, Fcnb, Il1b, and Vcsa1 to serve as biomarkers for flap failure in both arterial ischemia and venous congestion. Our data suggests that Prol1 and Vcsa1 may be specific indicators of venous congestion and

  17. Glycogen Synthase Kinase-3 Inhibitor Protects Against Microvascular Hyperpermeability Following Hemorrhagic Shock

    Science.gov (United States)

    Sawant, Devendra A.; Tharakan, Binu; Hunter, Felicia A.; Childs, Ed W.

    2015-01-01

    Background Hemorrhagic shock (HS)-induce microvascular hyperpermeability involves disruption of endothelial cell adherens junctions leading to increase in paracellular permeability. β-Catenin, an integral component of the adherens junctional complex and Wnt pathway, and caspase-3 via its apoptotic signaling regulate endothelial cell barrier integrity. We have hypothesized that inhibiting phosphorylation of β-catenin and caspase-3 activity using glycogen synthase kinase-3 (GSK-3) specific inhibitor SB216763, would attenuate microvascular hyperpermeability following HS. Methods In Sprague-Dawley rats, HS was induced by withdrawing blood to reduce mean arterial pressure to 40 mmHg for 60 minutes followed by resuscitation. Rats were given SB216763 (600 μg/kg) intravenously 10 minutes prior to shock. To study microvascular permeability, the rats were injected intravenously with FITC-albumin (50 mg/kg) and its flux across the mesenteric post-capillary venules was determined using intravital microscopy. In cell-culture studies, rat lung microvascular endothelial cell (RLMEC) monolayers grown on Transwell plates were pre-treated with SB216763 (5 μM) followed by BAK (5 μg/mL) and caspase-3 (5 μg/mL) protein transfection. FITC-albumin (5 mg/mL) flux across cell monolayers indicates change in monolayer permeability. Activity of canonical Wnt pathway was determined by luciferase assay. Caspase-3 enzyme activity was assayed fluorometrically. Results The HS group showed significant increase in FITC-albumin extravasation (p<0.05) compared with sham. SB216763 significantly decrease HS-induced FITC-albumin extravasation (p<0.05). Pre-treatment with SB216763, protected against a BAK-induced increase in RLMEC monolayer permeability and caspase-3 activity, but failed to show similar results with a caspase-3-induced increase in monolayer permeability. Wnt3a treatment showed an increase in β-catenin dependent TCF-mediated transcription. Conclusion Inhibiting phosphorylation of

  18. In vitro model of cerebral ischemia by using brain microvascular endothelial cells derived from human induced pluripotent stem cells.

    Science.gov (United States)

    Kokubu, Yasuhiro; Yamaguchi, Tomoko; Kawabata, Kenji

    2017-04-29

    Brain-derived microvascular endothelial cells (BMECs), which play a central role in blood brain barrier (BBB), can be used for the evaluation of drug transport into the brain. Although human BMEC cell lines have already been reported, they lack original properties such as barrier integrity. Pluripotent stem cells (PSCs) can be used for various applications such as regenerative therapy, drug screening, and pathological study. In the recent study, an induction method of BMECs from PSCs has been established, making it possible to more precisely study the in vitro human BBB function. Here, using induced pluripotent stem (iPS) cell-derived BMECs, we examined the effects of oxygen-glucose deprivation (OGD) and OGD/reoxygenation (OGD/R) on BBB permeability. OGD disrupted the barrier function, and the dysfunction was rapidly restored by re-supply of the oxygen and glucose. Interestingly, TNF-α, which is known to be secreted from astrocytes and microglia in the cerebral ischemia, prevented the restoration of OGD-induced barrier dysfunction in an apoptosis-independent manner. Thus, we could establish the in vitro BBB disease model that mimics the cerebral ischemia by using iPS cell-derived BMECs.

  19. Pericyte abundance affects sucrose permeability in cultures of rat brain microvascular endothelial cells.

    Science.gov (United States)

    Parkinson, Fiona E; Hacking, Cindy

    2005-07-05

    The blood-brain barrier is a physical and metabolic barrier that restricts diffusion of blood-borne substances into brain. In vitro models of the blood-brain barrier are used to characterize this structure, examine mechanisms of damage and repair and measure permeability of test substances. The core component of in vitro models of the blood-brain barrier is brain microvascular endothelial cells. We cultured rat brain microvascular endothelial cells (RBMEC) from isolated rat cortex microvessels. After 2-14 days in vitro (DIV), immunohistochemistry of these cells showed strong labeling for zona occludens 1 (ZO-1), a tight junction protein expressed in endothelial cells. Pericytes were also present in these cultures, as determined by expression of alpha-actin. The present study was performed to test different cell isolation methods and to compare the resulting cell cultures for abundance of pericytes and for blood-brain barrier function, as assessed by 14C-sucrose flux. Two purification strategies were used. First, microvessels were preabsorbed onto uncoated plastic for 4 h, then unattached microvessels were transferred to coated culture ware. Second, microvessels were incubated with an antibody to platelet-endothelial cell adhesion molecule 1 (PECAM-1; CD31) precoupled to magnetic beads, and a magnetic separation procedure was performed. Our results indicate that immunopurification, but not preadsorption, was an effective method to purify microvessels and reduce pericyte abundance in the resulting cultures. This purification significantly reduced 14C-sucrose fluxes across cell monolayers. These data indicate that pericytes can interfere with the development of blood-brain barrier properties in in vitro models that utilize primary cultures of RBMECs.

  20. Propionyl-L-Carnitine Enhances Wound Healing and Counteracts Microvascular Endothelial Cell Dysfunction.

    Directory of Open Access Journals (Sweden)

    Maria Giovanna Scioli

    Full Text Available Impaired wound healing represents a high cost for health care systems. Endothelial dysfunction characterizes dermal microangiopathy and contributes to delayed wound healing and chronic ulcers. Endothelial dysfunction impairs cutaneous microvascular blood flow by inducing an imbalance between vasorelaxation and vasoconstriction as a consequence of reduced nitric oxide (NO production and the increase of oxidative stress and inflammation. Propionyl-L-carnitine (PLC is a natural derivative of carnitine that has been reported to ameliorate post-ischemic blood flow recovery.We investigated the effects of PLC in rat skin flap and cutaneous wound healing. A daily oral PLC treatment improved skin flap viability and associated with reactive oxygen species (ROS reduction, inducible nitric oxide synthase (iNOS and NO up-regulation, accelerated wound healing and increased capillary density, likely favoring dermal angiogenesis by up-regulation for iNOS, vascular endothelial growth factor (VEGF, placental growth factor (PlGF and reduction of NADPH-oxidase 4 (Nox4 expression. In serum-deprived human dermal microvascular endothelial cell cultures, PLC ameliorated endothelial dysfunction by increasing iNOS, PlGF, VEGF receptors 1 and 2 expression and NO level. In addition, PLC counteracted serum deprivation-induced impairment of mitochondrial β-oxidation, Nox4 and cellular adhesion molecule (CAM expression, ROS generation and leukocyte adhesion. Moreover, dermal microvascular endothelial cell dysfunction was prevented by Nox4 inhibition. Interestingly, inhibition of β-oxidation counteracted the beneficial effects of PLC on oxidative stress and endothelial dysfunction.PLC treatment improved rat skin flap viability, accelerated wound healing and dermal angiogenesis. The beneficial effects of PLC likely derived from improvement of mitochondrial β-oxidation and reduction of Nox4-mediated oxidative stress and endothelial dysfunction. Antioxidant therapy and

  1. Diet Induced Obesity in Sprague Dawley Rats Causes Microvascular and Neural Dysfunction

    Science.gov (United States)

    Davidson, Eric P.; Coppey, Lawrence J.; Calcutt, Nigel A.; Oltman, Christine L.; Yorek, Mark A.

    2010-01-01

    Background The objective was to determine the effect of diet induced obesity (DIO) on microvascular and neural function. Methods Rats were fed a standard or high fat diet for up to 32 weeks. Measurements were performed of vasodilation in epineurial arterioles by videomicroscopy, endoneurial blood flow by hydrogen clearance, nerve conduction velocity by electrical stimulation, size-frequency distribution of myelinated fibers of the sciatic nerve, intraepidermal nerve fiber density using confocal microscopy and thermal nociception using the Hargreaves method. Results Rats fed a high fat diet for 32 weeks developed sensory neuropathy as indicated by slowing of sensory nerve conduction velocity and thermal hypoalgesia. Motor nerve conduction velocity and endoneurial blood flow were not impaired. Mean axonal diameter of myelinated fibers of the sciatic nerve was unchanged in high fat fed rats compared to control. Intraepidermal nerve fiber density was significantly reduced in high fat fed rats. Vascular relaxation to acetylcholine and calcitonin gene-related peptide was decreased and expression of neutral endopeptidase (NEP) increased in epineurial arterioles of rats fed a high fat diet. In contrast, insulin-mediated vascular relaxation was increased in epineurial arterioles. NEP activity was significantly increased in the skin of the hindpaw. Markers of oxidative stress were increased in the aorta and serum of high fat fed rats but not in epineurial arterioles. Conclusion Chronic obesity causes microvascular and neural dysfunction. This is associated with increased expression of NEP but not oxidative stress in epineurial arterioles. NEP degrades vasoactive peptides which may explain the decrease in microvascular function. PMID:20503263

  2. Role of genetic polymorphisms of ion channels in the pathophysiology of coronary microvascular dysfunction and ischemic heart disease.

    Science.gov (United States)

    Fedele, Francesco; Mancone, Massimo; Chilian, William M; Severino, Paolo; Canali, Emanuele; Logan, Suzanna; De Marchis, Maria Laura; Volterrani, Maurizio; Palmirotta, Raffaele; Guadagni, Fiorella

    2013-11-01

    Conventionally, ischemic heart disease (IHD) is equated with large vessel coronary disease. However, recent evidence has suggested a role of compromised microvascular regulation in the etiology of IHD. Because regulation of coronary blood flow likely involves activity of specific ion channels, and key factors involved in endothelium-dependent dilation, we proposed that genetic anomalies of ion channels or specific endothelial regulators may underlie coronary microvascular disease. We aimed to evaluate the clinical impact of single-nucleotide polymorphisms in genes encoding for ion channels expressed in the coronary vasculature and the possible correlation with IHD resulting from microvascular dysfunction. 242 consecutive patients who were candidates for coronary angiography were enrolled. A prospective, observational, single-center study was conducted, analyzing genetic polymorphisms relative to (1) NOS3 encoding for endothelial nitric oxide synthase (eNOS); (2) ATP2A2 encoding for the Ca²⁺/H⁺-ATPase pump (SERCA); (3) SCN5A encoding for the voltage-dependent Na⁺ channel (Nav1.5); (4) KCNJ8 and KCNJ11 encoding for the Kir6.1 and Kir6.2 subunits of K-ATP channels, respectively; and (5) KCN5A encoding for the voltage-gated K⁺ channel (Kv1.5). No significant associations between clinical IHD manifestations and polymorphisms for SERCA, Kir6.1, and Kv1.5 were observed (p > 0.05), whereas specific polymorphisms detected in eNOS, as well as in Kir6.2 and Nav1.5 were found to be correlated with IHD and microvascular dysfunction. Interestingly, genetic polymorphisms for ion channels seem to have an important clinical impact influencing the susceptibility for microvascular dysfunction and IHD, independent of the presence of classic cardiovascular risk factors.

  3. Use of intravital microscopy to study the microvascular behavior of microbubble-based ultrasound contrast agents.

    Science.gov (United States)

    Schneider, Michel; Broillet, Anne; Tardy, Isabelle; Pochon, Sibylle; Bussat, Philippe; Bettinger, Thierry; Helbert, Alexandre; Costa, Maria; Tranquart, François

    2012-04-01

    The study describes the use of intravital microscopy (IVM) to assess the behavior of ultrasound contrast agents (UCAs), including targeted UCAs, in the microcirculation of rodents. IVM was performed on various exteriorized organs: hamster cheek pouch, rat mesentery, liver, spinotrapezius muscle, and mouse cremaster muscle. A dorsal skin-fold chamber with MatBIII tumor cells was also implanted in rats. Nontargeted UCAs (SonoVue(®) and BR14) and targeted UCAs (BR55 and P-selectin targeted microbubbles) were tested. IVM was used to measure microbubble size, determine their persistence, and observe their behavior in the blood circulation. Intravenous and intra-arterial injections of high doses of UCAs did not modify the local microvascular hemodynamics. No microbubble coalescence and no increased size were observed. Adhesion of some microbubbles to leukocytes was observed in various microcirculation models. Microbubbles are captured by Kupffer cells in the liver. Targeted microbubbles were shown to adhere specifically to endothelial receptors without compromising local blood flow. These results support the safety of both targeted and nontargeted UCAs as no microvascular flow alteration or plugging of microvessels were observed. They confirm that binding observed with targeted microbubbles are due to the binding of these microbubbles to specific endothelial receptors. © 2012 John Wiley & Sons Ltd.

  4. Vasoconstrictor eicosanoids and impaired microvascular function in inactive and insulin-resistant primates.

    Science.gov (United States)

    Chadderdon, S M; Belcik, J T; Bader, L; Kievit, P; Grove, K L; Lindner, J R

    2016-10-01

    The inability to augment capillary blood volume (CBV) in response to insulin or glucose is thought to contribute to insulin resistance (IR) by limiting glucose uptake in key storage sites. Understanding the mechanisms that contribute to impaired CBV augmentation early in the onset of IR may lead to new future therapies. We hypothesized that inactivity alters the balance of vasoactive eicosanoids and contributes to microvascular IR. In ten activity-restricted (AR) and six normal activity adult male rhesus macaques, contrast-enhanced ultrasound of skeletal muscle blood flow and CBV was performed at baseline and during intravenous glucose tolerance test (IVGTT). Plasma was analyzed for vasoconstrictor hydroxyeicosatetraenoic acids (HETEs) and the ratio of vasodilatory epoxyeicosatrienoic acids (EETs) to their less biologically active dihydroxyeicosatrienoic acids (DHETs) as an indirect measure of soluble epoxide hydrolase activity. AR primates were IR during IVGTT and had a 45% lower glucose-stimulated CBV response. Vasoconstrictor 18-HETE and 19-HETE and the DHET/EET ratio were markedly elevated in the AR group and correlated inversely with the CBV response. In addition, levels of 18-HETE and 19-HETE correlated directly with microvascular IR. We conclude that a shift toward increased eicosanoid vasoconstrictor tone correlates with abnormal skeletal muscle vascular recruitment and may contribute to IR.

  5. [Microvascular and macrovascular complications in children and adolescents with type 1 diabetes mellitus].

    Science.gov (United States)

    Fröhlich-Reiterer, Elke E; Borkenstein, Martin H

    2010-08-01

    Diabetes-related microvascular and macrovascular complications, as retinopathy, nephropathy and neuropathy are life-threatening complications in children and adolescents with type 1 diabetes mellitus (T1DM). Risk factors for the development of complications are longer duration of diabetes, older age and puberty. Further risk factors include smoking, hypertension, higher body mass index and dyslipoproteinaemia. Therefore prevention and screening for complications is an important part in the care of children and adolescents with T1DM. Target levels to reduce the risk of microvascular and macrovascular complications in children and adolescents with T1DM are the following: HbA1cdiabetes duration and from 9 years with 5 years duration and after 2 years diabetes duration in an adolescent. Thereafter screening should be performed annually. Blood pressure should be measured at least annually. Screening for fasting blood lipids should be performed soon after diagnosis in all children with T1DM aged over 12 years. If normal results are obtained, this should be repeated every 5 years.

  6. Nursing Supplies

    Science.gov (United States)

    ... Stages Listen Español Text Size Email Print Share Nursing Supplies Page Content Article Body Throughout most of ... budget. (Nursing equipment also makes wonderful baby gifts.) Nursing Bras A well-made nursing bra that comfortably ...

  7. Microsurgical treatment of medial sphenoid ridge meningioma rich in blood supply%血供丰富内侧型蝶骨嵴脑膜瘤显微手术治疗(附28例临床分析)

    Institute of Scientific and Technical Information of China (English)

    何裕超; 窦以河; 王衍刚; 张欣

    2011-01-01

    Objective To explore the preoperative evaluation approach and microsurgical technique of medial sphenoid ridge meningioma rich in blood supply. Methods Twenty eight patients with medial sphenoid ridge meningioma rich in blood supply treated in our hospital in the past five years were reviewed r etrospectively. CT angiography (CTA) or digital subtraction an-giography (DSA) were used to detect the blood supply of the tumors. Results Of 28 cases, total removal w as made in 21 cases, subtotal removal in 6 cases and partial removal in 1 case. Glasow out scale(GOS) grade I and Ⅱ include 0 case, gradeⅢ includes 8 cases, grade IV includes 19 cases. Conclusion Complete preoperative evaluation and the combination of angiography and microsurgical treatment are of great help to the resection and prognosis of medial sphenoid ridge meningioma rich in blood supply.%目的 探讨血供丰富内侧型蝶骨嵴脑膜瘤的术前评估及治疗方法.方法 回顾性分析经显微手术治疗的28例血供丰富内侧型蝶骨嵴脑膜瘤,CTA或DSA明确瘤周血管走形及肿瘤血供情况,发现肿瘤血运丰富,首先行颈外动脉血管内栓塞治疗,然后经显微手术行脑膜瘤切除术,分析病人术后疗效及并发症等,总结治疗经验.结果 28例肿瘤全切除(Simpson分级Ⅰ、Ⅱ级)21例,次全切除(Simpson分级Ⅲ级)6例,部分切除(Simpson分级Ⅳ级)1例.格拉斯哥预后分级(glascow out scale,GOS)Ⅰ级0例,Ⅱ级0例,Ⅲ级8例,Ⅳ级19例,Ⅴ级1例.结论 完善术前评估及影像学检查,综合应用血管成像技术及栓塞术配合显微手术治疗血供丰富的内侧型蝶骨嵴脑膜瘤,对提高肿瘤切除程度,改善预后有积极意义.

  8. Microvascular dysfunction in nonfailing arrhythmogenic right ventricular cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Matthias [University Hospital Muenster, Department of Cardiology and Angiology, Muenster (Germany); University Hospital Muenster, Institute for Genetics of Heart Diseases, Muenster (Germany); Rahbar, Kambiz; Kies, Peter; Schober, Otmar [University Hospital Muenster, Department of Nuclear Medicine, Muenster (Germany); Gerss, Joachim [University of Muenster, Institute of Biostatistics and Clinical Research, Muenster (Germany); Schaefers, Klaus; Schaefers, Michael [University of Muenster, European Institute for Molecular Imaging - EIMI, Muenster (Germany); Breithardt, Guenter [University Hospital Muenster, Department of Cardiology and Angiology, Muenster (Germany); Schulze-Bahr, Eric [University Hospital Muenster, Institute for Genetics of Heart Diseases, Muenster (Germany); Wichter, Thomas [Marienhospital Osnabrueck, Department of Cardiology, Niels-Stensen-Kliniken, Osnabrueck (Germany)

    2012-03-15

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a nonischaemic cardiomyopathy and leading cause of sudden death in the young. It has been shown that microvascular dysfunction reflected by an impaired myocardial blood flow (MBF) response to stress is present in patients with other forms of nonischaemic cardiomyopathy, e.g. dilated cardiomyopathy, and that the reduced MBF may be related to a poor prognosis. Therefore, we quantified MBF, coronary flow reserve and coronary vascular resistance in patients with nonfailing ARVC using H{sub 2}{sup 15} O and PET. In ten male patients with ARVC (mean age 49 {+-} 14 years), MBF was quantified at rest and during adenosine-induced hyperaemia using H{sub 2}{sup 15} O PET. Results were compared with those obtained in 20 age-matched healthy male control subjects (mean age 46 {+-} 14 years). Resting MBF was not significantly different between patients with ARVC and controls (MBF{sub rest} 1.19 {+-} 0.29 vs. 1.12 {+-} 0.20 ml/min/ml). However, hyperaemic MBF was significantly lower in patients with ARVC than in controls (2.60 {+-} 0.96 vs. 3.68 {+-} 0.84 ml/min/ml; p = 0.005). Consequently, patients with ARVC had a significantly lower coronary flow reserve than control subjects (2.41 {+-} 1.34 vs. 3.39 {+-} 0.93; p = 0.030). In addition, hyperaemic coronary vascular resistance was increased in patients with ARVC (36.79 {+-} 12.91 vs. 26.31 {+-} 6.49 mmHg x ml{sup -1} x min x ml; p = 0.007), but was found to be unchanged at rest. In this small well-characterized cohort of patients with nonfailing ARVC, we found a significantly reduced hyperaemic MBF and increased coronary vascular resistance. Further studies are necessary to corroborate this potential new functional aspect of the pathophysiological mechanisms underlying ARVC. (orig.)

  9. ‘Short-term treatment with methotrexate does not affect microvascular endothelial function in patients with psoriasis’

    DEFF Research Database (Denmark)

    Gyldenløve, M; Jensen, Peter; Løvendorf, M B

    2015-01-01

    influences microvascular endothelial function (MEF), an early surrogate marker of atherosclerosis, in patients with psoriasis. METHODS: We prospectively studied a hospital cohort of patients with psoriasis. Measurements of MEF were performed with the Endo-PAT2000© device at baseline and after 8-10 weeks...... by 7 (from 9 to 2). No significant changes were observed in MEF, expressed by reactive hyperaemia index and augmentation index. Also, we saw no significant changes in BMI, waist-hip ratio, blood pressure and blood samples. CONCLUSION: Short-term treatment with methotrexate did not affect MEF...

  10. IL-1α-induced microvascular endothelial cells promote neutrophil killing by increasing MMP-9 concentration and lysozyme activity.

    Science.gov (United States)

    Liu, Xiaoye; Dong, Hong; Wang, Mingming; Gao, Ying; Zhang, Tao; Hu, Ge; Duan, Huiqing; Mu, Xiang

    2016-02-01

    The recruitment of neutrophils by endothelial cells during infection has been extensively studied, but little is known about the regulation of neutrophils activity by endothelial cells. To examine the role of microvascular endothelial cells in neutrophil killing, we established a transmigration model using rat intestinal microvascular endothelial cells (RIMVECs) and measured the extracellular and intracellular killing of Escherichia coli, Lactobacillus acidophilus, and Staphylococcus aureus by transendothelial neutrophils. We observed that blood neutrophils engulfed bacteria but did not kill them, and lipopolysaccharide- or hemolysin-injured RIMVECs inhibited the extracellular and intracellular bactericidal activity of transendothelial neutrophils. In comparison, interleukin-1α-induced RIMVECs promoted the extracellular and intracellular killing activity of transendothelial neutrophils and significantly increased MMP-9 concentration and lysozyme activity in transendothelial neutrophils (p neutrophils and bacterial toxin damage of endothelial cells led to reduction in bactericidal activity of transendothelial neutrophils. These findings offered new insight into the role of endothelial cells in the bactericidal activity of neutrophils.

  11. A Novel Microvascular Flow Technique: Initial Results in Thyroids.

    Science.gov (United States)

    Machado, Priscilla; Segal, Sharon; Lyshchik, Andrej; Forsberg, Flemming

    2016-03-01

    To evaluate the flow imaging capabilities of a new prototype ultrasound (US) image processing technique (superb micro-vascular imaging [SMI]; Toshiba Medical Systems, Tokyo, Japan) for depiction of microvascular flow in normal thyroid tissue and thyroid nodules compared with standard color and power Doppler US imaging.Ten healthy volunteers and 22 patients, with a total of 25 thyroid nodules, scheduled for US-guided fine needle aspiration were enrolled in this prospective study. Subjects underwent US examination consisting of grayscale, color and power Doppler imaging (CDI and PDI) followed by color and monochrome SMI and pulsed Doppler. SMI is a novel, microvascular flow imaging mode implemented on the Aplio 500 US system (Toshiba). SMI uses advanced clutter suppression to extract flow signals from large to small vessels and depicts this information at high frame rates as a color overlay image or as a monochrome map of flow. Two radiologists independently scored still images and digital clips for overall flow detection, vessel branching details and noise on a visual-analog scale of 1 (worst) to 10 (best).For the volunteers SMI visualized microvasculature with significantly lower velocity than CDI and PDI (P SMI demonstrated microvascular flow with significantly higher image scores and provided better depiction of the vessel branching details compared with CDI and PDI (P SMI mode than in the other modes, including color SMI (P SMI mode consistently improved the depiction of thyroid microvascular flow compared with standard CDI and PDI.

  12. Diabetic Peripheral Microvascular Complications: Relationship to Cognitive Function

    Directory of Open Access Journals (Sweden)

    Lorraine Ba-Tin

    2011-01-01

    Full Text Available Peripheral microvascular complications in diabetes are associated with concurrent cerebrovascular disease. As detailed cognitive assessment is not routinely carried out among diabetic patients, the aim was to establish whether the presence of clinical “peripheral” microvascular disease can identify a subgroup of patients with early evidence of cognitive impairment. Detailed psychometric assessment was performed in 23 diabetic patients with no microvascular complications (Group D, 27 diabetic patients with at least one microvascular complication: retinopathy, neuropathy, and/or nephropathy (Group DC, and 25 healthy controls (Group H. Groups D and DC participants had significantly lower scores on reaction time (P=0.003 and 0.0001, resp. compared to controls. Similarly, groups D and DC participants had significantly lower scores on rapid processing of visual information (P=0.034 and 0.001, resp. compared to controls. In contrast, there was no significant difference between Groups D and DC on any of the cognitive areas examined. The results show that diabetes, in general, is associated with cognitive dysfunction, but the additional presence of peripheral microvascular disease does not add to cognitive decline. The study, however, indirectly supports the notion that the aetiology of cognitive impairment in diabetes may not be restricted to vascular pathology.

  13. Magnetic particle spectroscopy allows precise quantification of nanoparticles after passage through human brain microvascular endothelial cells

    Science.gov (United States)

    Gräfe, C.; Slabu, I.; Wiekhorst, F.; Bergemann, C.; von Eggeling, F.; Hochhaus, A.; Trahms, L.; Clement, J. H.

    2016-06-01

    Crossing the blood-brain barrier is an urgent requirement for the treatment of brain disorders. Superparamagnetic iron oxide nanoparticles (SPIONs) are a promising tool as carriers for therapeutics because of their physical properties, biocompatibility, and their biodegradability. In order to investigate the interaction of nanoparticles with endothelial cell layers in detail, in vitro systems are of great importance. Human brain microvascular endothelial cells are a well-suited blood-brain barrier model. Apart from generating optimal conditions for the barrier-forming cell units, the accurate detection and quantification of SPIONs is a major challenge. For that purpose we use magnetic particle spectroscopy to sensitively and directly quantify the SPION-specific iron content. We could show that SPION concentration depends on incubation time, nanoparticle concentration and location. This model system allows for further investigations on particle uptake and transport at cellular barriers with regard to parameters including particles’ shape, material, size, and coating.

  14. The impact of early aerobic exercise on brain microvascular alterations induced by cerebral hypoperfusion.

    Science.gov (United States)

    Leardini-Tristão, Marina; Borges, Juliana Pereira; Freitas, Felipe; Rangel, Raquel; Daliry, Anissa; Tibiriçá, Eduardo; Estato, Vanessa

    2017-02-15

    The therapeutic potential of early exercise training following cerebral hypoperfusion was investigated on brain perfusion and inflammation in rats with permanent bilateral occlusion of the common carotid arteries (2VO). Wistar rats were subjected to 2VO or sham surgery and each group was then subdivided randomly into sedentary or exercise groups. Early exercise training was initiated after three days of 2VO or sham surgery and consisted of seven days of treadmill training (30min/day at ∼60% of maximal exercise test), composing four groups: 1) Sham sedentary (Sham-Sed), 2) Sham exercised (Sham-Ex), 3) 2VO sedentary (2VO-Sed) and 4) 2VO exercised (2VO-Ex). Microvascular cerebral blood flow (MCBF) and NADPH oxidase and eNOS gene expression were evaluated by laser speckle contrast imaging and RT-PCR, respectively, and brain functional capillary density and endothelial-leukocyte interactions were evaluated by fluorescence intravital video-microscopy. The 2VO-Sed group presented a decrease in MCBF (Sham-Sed: 230.9±12.2 vs. 2VO-Sed: 183.6±10.6 arbitrary perfusion units, Pexercise was able to prevent the cerebral microvascular inflammation by decreasing endothelial-leukocyte interactions (2VO-Ex: 0.9±0.3 vs. 2VO-Sed: 5±0.6cells/min/100μm, Pbrain NADPH oxidase gene expression (2VO-Ex: 1.7±0.1 arbitrary units, Pexercise may represent a means of preventing the microvascular alterations induced by chronic cerebral hypoperfusion.

  15. Correlation Factor Analysis of Retinal Microvascular Changes in Patients With Essential Hypertension

    Institute of Scientific and Technical Information of China (English)

    Huang Duru; Huang Zhongning

    2006-01-01

    Objectives To investigate correlation between retinal microvascular signs and essential hypertension classification. Methods The retinal microvascular signs in patients with essential hypertension were assessed with the indirect biomicroscopy lens, the direct and the indirect ophthalmoscopes were used to determine the hypertensive retinopathy grades and retinal arteriosclerosis grades.The rank correlation analysis was used to analysis the correlation these grades with the risk factors concerned with hypertension. Results Of 72 cases with essential hypertension, 28 cases complicated with coronary disease, 20 cases diabetes, 41 cases stroke,17 cases renal malfunction. Varying extent retinal arterioscleroses were found in 71 cases, 1 case with retinal hemorrhage, 2 cases with retina edema, 4 cases with retinal hard exudation, 5 cases with retinal hemorrhage complicated by hard exudation, 2 cases with retinal hemorrhage complicated by hard exudation and cotton wool spot, 1 case with retinal hemorrhage complicated by hard exudation and microaneurysms,1 case with retinal edema and hard exudation, 1 case with retinal microaneurysms, 1 case with branch retinal vein occlusion. The rank correlation analysis showed that either hypertensive retinopathy grades or retinal arteriosclerosis grades were correlated with risk factor lamination of hypertension (r=0.25 or 0.31, P<0.05), other correlation factors included age and blood high density lipoprotein concerned about hypertensive retinopathy grades or retinal arteriosclerosis grades, but other parameters, namely systolic or diastolic pressure, total cholesterol, triglyceride, low density lipoprotein cholesterol, fasting blood glucose,blood urea nitrogen and blood creatinine were not confirmed in this correlation analysis (P > 0.05).Conclusions Either hypertensive retinopathy grade or retinal arteriosclerosis grade is close with the hypertension risk factor lamination, suggesting that the fundus examination of patients with

  16. Profile of Microvascular Disease in Type 2 Diabetes in a Tertiary ...

    African Journals Online (AJOL)

    Morbidity and mortality in patients with type 2 diabetes mellitus. (T2DM) is attributed to the microvascular and macrovascular ... the clinical profile of microvascular diabetes complications [peripheral sensory neuropathy ..... District, south India.

  17. Active cooling of microvascular composites for battery packaging

    Science.gov (United States)

    Pety, Stephen J.; Chia, Patrick X. L.; Carrington, Stephen M.; White, Scott R.

    2017-10-01

    Batteries in electric vehicles (EVs) require a packaging system that provides both thermal regulation and crash protection. A novel packaging scheme is presented that uses active cooling of microvascular carbon fiber reinforced composites to accomplish this multifunctional objective. Microvascular carbon fiber/epoxy composite panels were fabricated and their cooling performance assessed over a range of thermal loads and experimental conditions. Tests were performed for different values of coolant flow rate, channel spacing, panel thermal conductivity, and applied heat flux. More efficient cooling occurs when the coolant flow rate is increased, channel spacing is reduced, and thermal conductivity of the host composite is increased. Computational fluid dynamics (CFD) simulations were also performed and correlate well with the experimental data. CFD simulations of a typical EV battery pack confirm that microvascular composite panels can adequately cool battery cells generating 500 W m‑2 heat flux below 40 °C.

  18. 血站供电应急预案的实现%Realization of Power-supply Emergency Plan in Blood Center

    Institute of Scientific and Technical Information of China (English)

    张晋

    2011-01-01

    This paper provides an overview about realization of emergency plan and design and lectotype of main equipment of Qingdao Blood Station.%本文扼要介绍了青岛血站供电应急预案实现以及主要设备的设计、选型.

  19. Retinal Microvascular Abnormalities in Neurofibromatosis Type 1 Associated with Congenital Retinal Macrovessels

    Science.gov (United States)

    Makino, Shinji; Endoh, Katsuhisa; Tampo, Hironobu

    2013-01-01

    Here, we report a case of retinal microvascular abnormalities in a patient with neurofibromatosis type 1 (NF1) associated with congenital retinal macrovessels. An abnormal retinal macrovessel, crossing the macula horizontally, was detected in the right eye. Additionally, retinal microvascular abnormalities were detected. Eight years after the initial visit, the retinal microvascular abnormalities were noted to have changed substantially. We speculate that retinal microvascular abnormalities in NF1 may change dynamically over the years. PMID:23781366

  20. Retinal Microvascular Abnormalities in Neurofibromatosis Type 1 Associated with Congenital Retinal Macrovessels

    Directory of Open Access Journals (Sweden)

    Shinji Makino

    2013-01-01

    Full Text Available Here, we report a case of retinal microvascular abnormalities in a patient with neurofibromatosis type 1 (NF1 associated with congenital retinal macrovessels. An abnormal retinal macrovessel, crossing the macula horizontally, was detected in the right eye. Additionally, retinal microvascular abnormalities were detected. Eight years after the initial visit, the retinal microvascular abnormalities were noted to have changed substantially. We speculate that retinal microvascular abnormalities in NF1 may change dynamically over the years.

  1. Metabolic dynamics in skeletal muscle during acute reduction in blood flow and oxygen supply to mitochondria: in-silico studies using a multi-scale, top-down integrated model.

    Science.gov (United States)

    Dash, Ranjan K; Li, Yanjun; Kim, Jaeyeon; Beard, Daniel A; Saidel, Gerald M; Cabrera, Marco E

    2008-09-09

    Control mechanisms of cellular metabolism and energetics in skeletal muscle that may become evident in response to physiological stresses such as reduction in blood flow and oxygen supply to mitochondria can be quantitatively understood using a multi-scale computational model. The analysis of dynamic responses from such a model can provide insights into mechanisms of metabolic regulation that may not be evident from experimental studies. For the purpose, a physiologically-based, multi-scale computational model of skeletal muscle cellular metabolism and energetics was developed to describe dynamic responses of key chemical species and reaction fluxes to muscle ischemia. The model, which incorporates key transport and metabolic processes and subcellular compartmentalization, is based on dynamic mass balances of 30 chemical species in both capillary blood and tissue cells (cytosol and mitochondria) domains. The reaction fluxes in cytosol and mitochondria are expressed in terms of a general phenomenological Michaelis-Menten equation involving the compartmentalized energy controller ratios ATP/ADP and NADH/NAD(+). The unknown transport and reaction parameters in the model are estimated simultaneously by minimizing the differences between available in vivo experimental data on muscle ischemia and corresponding model outputs in coupled with the resting linear flux balance constraints using a robust, nonlinear, constrained-based, reduced gradient optimization algorithm. With the optimal parameter values, the model is able to simulate dynamic responses to reduced blood flow and oxygen supply to mitochondria associated with muscle ischemia of several key metabolite concentrations and metabolic fluxes in the subcellular cytosolic and mitochondrial compartments, some that can be measured and others that can not be measured with the current experimental techniques. The model can be applied to test complex hypotheses involving dynamic regulation of cellular metabolism and

  2. Preventing the parathyroid glands and their blood supplies during level VI lymphadenectomy of thyroid cancer surgery%甲状腺癌Ⅵ区清扫术中预防甲状旁腺损伤的术式探讨

    Institute of Scientific and Technical Information of China (English)

    齐宏

    2011-01-01

    Objective: To discuss how to identify and protect the parathyroid glands and their blood supplies during level Ⅵ lymphadenectomy of thyroid cancer surgery.Methods: During operation ,the parathyroid glands were exposed and preserved ,and the trunk of thyroid arteries were avoided to ligate.After operation,the function of parathyroid was observed.Results: Before operation,the blood concentrations in patients received ligating the trunk of thyroid arteries were almost the same compared to those without ligating the arteries,there was no statistical difference,but after operation,there was statistical difference(P<0.01 ).Conclusion: During level Ⅵ lymphadenectomy of thyroid cancer surgery,parathyroid glands and its artery blood-supply should be exposed and preserved to prevent hypoparathyroidism after surgery.%目的:探讨甲状腺癌Ⅵ区清扫术中保留甲状腺血管后支对甲状旁腺血运及功能的影响.方法:采用传统方法行甲状腺癌VI区淋巴结清扫及术中保留甲状腺上下血管后支方法的手术,术后观察甲状旁腺的血运及功能变化.结果:甲状腺癌Ⅵ区淋巴结清扫术中保留甲状旁腺上下血管后支可明显阳氏对甲状旁腺血运和功能影响.结论:甲状腺癌Ⅵ区清扫术中保留甲状腺血管后支可有效预访甲状旁腺功静低下.

  3. Non-Invasive Measurement of Skin Microvascular Response during Pharmacological and Physiological Provocations.

    Directory of Open Access Journals (Sweden)

    Fredrik Iredahl

    Full Text Available Microvascular changes in the skin due to pharmacological and physiological provocations can be used as a marker for vascular function. While laser Doppler flowmetry (LDF has been used extensively for measurement of skin microvascular responses, Laser Speckle Contrast Imaging (LSCI and Tissue Viability Imaging (TiVi are novel imaging techniques. TiVi measures red blood cell concentration, while LDF and LSCI measure perfusion. Therefore, the aim of this study was to compare responses to provocations in the skin using these different techniques.Changes in skin microcirculation were measured in healthy subjects during (1 iontophoresis of sodium nitroprusside (SNP and noradrenaline (NA, (2 local heating and (3 post-occlusive reactive hyperemia (PORH using LDF, LSCI and TiVi.Iontophoresis of SNP increased perfusion (LSCI: baseline 40.9±6.2 PU; 10-min 100±25 PU; p<0.001 and RBC concentration (TiVi: baseline 119±18; 10-min 150±41 AU; p = 0.011. No change in perfusion (LSCI was observed after iontophoresis of NA (baseline 38.0±4.4 PU; 10-min 38.9±5.0 PU; p = 0.64, while RBC concentration decreased (TiVi: baseline 59.6±11.8 AU; 10-min 54.4±13.3 AU; p = 0.021. Local heating increased perfusion (LDF: baseline 8.8±3.6 PU; max 112±55 PU; p<0.001, LSCI: baseline 50.8±8.0 PU; max 151±22 PU; p<0.001 and RBC concentration (TiVi: baseline 49.2±32.9 AU; max 99.3±28.3 AU; p<0.001. After 5 minutes of forearm occlusion with prior exsanguination, a decrease was seen in perfusion (LDF: p = 0.027; LSCI: p<0.001 and in RBC concentration (p = 0.045. Only LSCI showed a significant decrease in perfusion after 5 minutes of occlusion without prior exsanguination (p<0.001. Coefficients of variation were lower for LSCI and TiVi compared to LDF for most responses.LSCI is more sensitive than TiVi for measuring microvascular changes during SNP-induced vasodilatation and forearm occlusion. TiVi is more sensitive to noradrenaline-induced vasoconstriction. LSCI and Ti

  4. Rotary blood-supplied patches for the treatment of osteomyelitis of the bones of the foot and the distal third of the tibia

    Directory of Open Access Journals (Sweden)

    V. V. Yurkevich

    2012-01-01

    Full Text Available The results of 112 transpositions of blood receiving complexes tissue foot applied in the treatment of chronic posttraumatic osteomyelitis of the bones of the foot and the distal third of the shin. Positive results were obtained in 86,6% of patients with recovery to work in 81,5% of the patients. The authors argue that the proposed blood receiving complexes tissue foot in the treatment of chronic posttraumatic osteomyelitis of the bones of the foot and the distal third of the shin allow to depart from the practice of multistage operations, reduce the time of hospital treatment. The algorithm for help in the treatment of chronic posttraumatic osteomyelitis of the bones of the foot and the distal third of the shin.

  5. Circulating endothelial progenitor cells, microvascular density and fibrosis in obesity before and after bariatric surgery.

    Science.gov (United States)

    De Ciuceis, Carolina; Rossini, Claudia; Porteri, Enzo; La Boria, Elisa; Corbellini, Claudia; Mittempergher, Francesco; Di Betta, Ernesto; Petroboni, Beatrice; Sarkar, Annamaria; Agabiti-Rosei, Claudia; Casella, Claudio; Nascimbeni, Riccardo; Rezzani, Rita; Rodella, Luigi F; Bonomini, Francesca; Agabiti-Rosei, Enrico; Rizzoni, Damiano

    2013-06-01

    It is not known whether, in obesity, the capillary density or the number of circulating endothelial progenitor cells (EPCs) are reduced, or whether fibrosis of small vessels is also present. In addition, possible effects of weight reduction on these parameters have never been evaluated. Therefore, we investigated EPCs and capillary density in 25 patients with severe obesity, all submitted to bariatric surgery, and in 18 normotensive lean subjects and 12 hypertensive lean patients as controls. All patients underwent a biopsy of subcutaneous fat during bariatric surgery. In five patients, a second biopsy was obtained after consistent weight loss, about 1 year later, during a surgical intervention for abdominoplasty. EPCs and capillary density were reduced in obesity, and EPCs were significantly increased after weight reduction. Vascular collagen content was clearly increased in obese patients. No significant difference in vascular collagen was observed between normotensive obese patients and hypertensive obese patients. After pronounced weight reduction, collagen content was nearly normalized. No difference in stress-strain relation was observed among groups or before and after weight loss. In conclusion, our data suggest that microvascular rarefaction occurs in obesity. EPCs were significantly reduced in obese patients. Pronounced weight loss induced by bariatric surgery seems to induce a significant improvement of EPC number, but not of capillary rarefaction. A pronounced fibrosis of subcutaneous small resistance arteries is present in obese patients, regardless of the presence of increased blood pressure values. Consistent weight loss induced by bariatric surgery may induce an almost complete regression of microvascular fibrosis.

  6. Sutureless microvascular anastomosis assisted by an expandable shape-memory alloy stent.

    Science.gov (United States)

    Saegusa, Noriko; Sarukawa, Shunji; Ohta, Kunihiro; Takamatsu, Kensuke; Watanabe, Mitsuhiro; Sugino, Takashi; Nakagawa, Masahiro; Akiyama, Yasuto; Kusuhara, Masatoshi; Kishi, Kazuo; Inoue, Keita

    2017-01-01

    Vascular anastomosis is the highlight of cardiovascular, transplant, and reconstructive surgery, which has long been performed by hand using a needle and suture. However, anastomotic thrombosis occurs in approximately 0.5-10% of cases, which can cause serious complications. To improve the surgical outcomes, attempts to develop devices for vascular anastomosis have been made, but they have had limitations in handling, cost, patency rate, and strength at the anastomotic site. Recently, indwelling metal stents have been greatly improved with precise laser metalwork through programming technology. In the present study, we designed a bare metal stent, Microstent, that was constructed by laser machining of a shape-memory alloy, NiTi. An end-to-end microvascular anastomosis was performed in SD rats by placing the Microstent at the anastomotic site and gluing the junction. The operation time for the anastomosis was significantly shortened using Microstent. Thrombus formation, patency rate, and blood vessel strength in the Microstent anastomosis were superior or comparable to hand-sewn anastomosis. The results demonstrated the safety and effectiveness, as well as the operability, of the new method, suggesting its great benefit for surgeons by simplifying the technique for microvascular anastomosis.

  7. Microvascular anastomosis in rodent model evaluated by Fourier domain Doppler optical coherence tomography

    Science.gov (United States)

    Huang, Yong; Tong, Dedi; Zhu, Shan; Wu, Lehao; Ibrahim, Zuhaib; Lee, WP Andrew; Brandacher, Gerald; Kang, Jin U.

    2014-03-01

    Vascular and microvascular anastomosis are critical components of reconstructive microsurgery, vascular surgery and transplant surgery. Imaging modality that provides immediate, real-time in-depth view and 3D structure and flow information of the surgical site can be a great valuable tool for the surgeon to evaluate surgical outcome following both conventional and innovative anastomosis techniques, thus potentially increase the surgical success rate. Microvascular anastomosis for vessels with outer diameter smaller than 1.0 mm is extremely challenging and effective evaluation of the outcome is very difficult if not impossible using computed tomography (CT) angiograms, magnetic resonance (MR) angiograms and ultrasound Doppler. Optical coherence tomography (OCT) is a non-invasive high-resolution (micron level), high-speed, 3D imaging modality that has been adopted widely in biomedical and clinical applications. Phaseresolved Doppler OCT that explores the phase information of OCT signals has been shown to be capable of characterizing dynamic blood flow clinically. In this work, we explore the capability of Fourier domain Doppler OCT as an evaluation tool to detect commonly encountered post-operative complications that will cause surgical failure and to confirm positive result with surgeon's observation. Both suture and cuff based techniques were evaluated on the femoral artery and vein in the rodent model.

  8. Imaging Evaluation of Blood Supply in Deep Inferior Epigastric Perforator Skin Flap%影像学评估腹壁下动脉穿支皮瓣血运的研究进展

    Institute of Scientific and Technical Information of China (English)

    孙敬岩

    2012-01-01

    应用不同影像学方法评估游离皮瓣的穿支血管走行及血供特性在乳房再造术中的重要作用.腹壁下动脉穿支(deep inferior epigastric perforator,DIEP)皮瓣属穿支皮瓣,穿支血管细小,解剖变异大,术前影像评估穿支血管的位置,管径大小及其走行,对提高手术成功率和安全性具有重要意义.评估血管的方法包括手持多普勒、色彩双超声、数字减影血管造影、CT血管造影、核磁血管造影、多层螺旋CT以及吲哚菁绿激光辅助的血管造影等,本文初步介绍不同检查方法评估DIEP皮瓣血管走行及血供特性的优缺点,辅助乳腺癌乳房再造术中血管分布的评估.%The use of various imaging methods to evaluate the characteristics of vascular direction and blood supply in the perforator artery of the free flap plays an important role in breast reconstruction. The deep inferior epigastric perforator ( DIEP ) flap has tiny blood vessels but its anatomy varies in individuals. The use of preoperative imaging on vascular position, pipe diameter size, and vascular direction can improve the success rate and safety of surgery. The evaluation methods used in blood circulation include hand-held doppler, color duplex ultrasound examination, digital subtraction angiography, angiography, imaging angiography, modified discrete cosine transform, and indocyanine green laser-assisted angiography. This article introduces the merits and demerits of different preliminary inspection methods used in evaluating the features of vascular direction and blood supply of the DIEP flap, as well as the distribution of blood vessels during adjuvant breast reconstruction.

  9. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows

    Science.gov (United States)

    Brust, M.; Aouane, O.; Thiébaud, M.; Flormann, D.; Verdier, C.; Kaestner, L.; Laschke, M. W.; Selmi, H.; Benyoussef, A.; Podgorski, T.; Coupier, G.; Misbah, C.; Wagner, C.

    2014-03-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects.

  10. Neuregulin1-β decreases IL-1β-induced neutrophil adhesion to human brain microvascular endothelial cells.

    Science.gov (United States)

    Wu, Limin; Walas, Samantha; Leung, Wendy; Sykes, David B; Wu, Jiang; Lo, Eng H; Lok, Josephine

    2015-04-01

    Neuroinflammation contributes to the pathophysiology of diverse diseases including stroke, traumatic brain injury, Alzheimer's disease, Parkinson's disease, and multiple sclerosis, resulting in neurodegeneration and loss of neurological function. The response of the microvascular endothelium often contributes to neuroinflammation. One such response is the upregulation of endothelial adhesion molecules which facilitate neutrophil adhesion to the endothelium and their migration from blood to tissue. Neuregulin-1 (NRG1) is an endogenous growth factor which has been reported to have anti-inflammatory effects in experimental stroke models. We hypothesized that NRG1 would decrease the endothelial response to inflammation and result in a decrease in neutrophil adhesion to endothelial cells. We tested this hypothesis in an in vitro model of cytokine-induced endothelial injury, in which human brain microvascular endothelial cells (BMECs) were treated with IL-1β, along with co-incubation with vehicle or NRG1-β. Outcome measures included protein levels of endothelial ICAM-1, VCAM-1, and E-selectin, as well as the number of neutrophils that adhere to the endothelial monolayer. Our data show that NRG1-β decreased the levels of VCAM-1, E-selectin, and neutrophil adhesion to brain microvascular endothelial cells activated by IL1-β. These findings open new possibilities for investigating NRG1 in neuroprotective strategies in brain injury.

  11. Microvascular response to transfusion in elective spine surgery

    Science.gov (United States)

    Walz, J Matthias; Stundner, Ottokar; Girardi, Federico P; Barton, Bruce A; Koll-Desrosiers, Aimee R; Heard, Stephen O; Memtsoudis, Stavros G

    2017-01-01

    AIM To investigate the microvascular (skeletal muscle tissue oxygenation; SmO2) response to transfusion in patients undergoing elective complex spine surgery. METHODS After IRB approval and written informed consent, 20 patients aged 18 to 85 years of age undergoing > 3 level anterior and posterior spine fusion surgery were enrolled in the study. Patients were followed throughout the operative procedure, and for 12 h postoperatively. In addition to standard American Society of Anesthesiologists monitors, invasive measurements including central venous pressure, continual analysis of stroke volume (SV), cardiac output (CO), cardiac index (CI), and stroke volume variability (SVV) was performed. To measure skeletal muscle oxygen saturation (SmO2) during the study period, a non-invasive adhesive skin sensor based on Near Infrared Spectroscopy was placed over the deltoid muscle for continuous recording of optical spectra. All administration of fluids and blood products followed standard procedures at the Hospital for Special Surgery, without deviation from usual standards of care at the discretion of the Attending Anesthesiologist based on individual patient comorbidities, hemodynamic status, and laboratory data. Time stamps were collected for administration of colloids and blood products, to allow for analysis of SmO2 immediately before, during, and after administration of these fluids, and to allow for analysis of hemodynamic data around the same time points. Hemodynamic and oxygenation variables were collected continuously throughout the surgery, including heart rate, blood pressure, mean arterial pressure, SV, CO, CI, SVV, and SmO2. Bivariate analyses were conducted to examine the potential associations between the outcome of interest, SmO2, and each hemodynamic parameter measured using Pearson’s correlation coefficient, both for the overall cohort and within-patients individually. The association between receipt of packed red blood cells and SmO2 was performed by

  12. Correlation between dynamic contrast-enhanced MRI and quantitative histopathologic microvascular parameters in organ-confined prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Niekerk, Cornelis G. van; Laak, Jeroen A.W.M. van der; Kaa, Christina A.H. de [Radboud University Medical Centre, Department of Pathology, P.O. Box 9101, Nijmegen (Netherlands); Hambrock, Thomas; Huisman, Henk-Jan; Barentsz, Jelle O. [Radboud University Medical Centre, Department of Radiology, Nijmegen (Netherlands); Witjes, J.A. [Radboud University Medical Centre, Department of Urology, Nijmegen (Netherlands)

    2014-10-15

    To correlate pharmacokinetic parameters of 3-T dynamic contrast-enhanced (DCE-)MRI with histopathologic microvascular and lymphatic parameters in organ-confined prostate cancer. In 18 patients with unilateral peripheral zone (pT2a) tumours who underwent DCE-MRI prior to radical prostatectomy (RP), the following pharmacokinetic parameters were assessed: permeability surface area volume transfer constant (K{sup trans}), extravascular extracellular volume (Ve) and rate constant (K{sub ep}). In the RP sections blood and lymph vessels were visualised immunohistochemically and automatically examined and analysed. Parameters assessed included microvessel density (MVD), area (MVA) and perimeter (MVP) as well as lymph vessel density (LVD), area (LVA) and perimeter (LVP). A negative correlation was found between age and K{sup trans} and K{sub ep} for tumour (r = -0.60, p = 0.009; r = -0.67, p = 0.002) and normal (r = -0.54, p = 0.021; r = -0.46, p = 0.055) tissue. No correlation existed between absolute values of microvascular parameters from histopathology and DCE-MRI. In contrast, the ratio between tumour and normal tissue (correcting for individual microvascularity variations) significantly correlated between K{sub ep} and MVD (r = 0.61, p = 0.007) and MVP (r = 0.54, p = 0.022). The lymphovascular parameters showed only a correlation between LVA and K{sub ep} (r = -0.66, p = 0.003). Significant correlations between DCE-MRI and histopathologic parameters were found when correcting for interpatient variations in microvascularity. (orig.)

  13. The impact of obesity on the relationship between epicardial adipose tissue, left ventricular mass and coronary microvascular function

    Energy Technology Data Exchange (ETDEWEB)

    Bakkum, M.J.; Danad, I.; Romijn, M.A.J.; Stuijfzand, W.J.A.; Leonora, R.M.; Rossum, A.C. van; Knaapen, P. [VU University Medical Center, Department of Cardiology, Amsterdam (Netherlands); Tulevski, I.I.; Somsen, G.A. [Cardiology Centers of the Netherlands, Amsterdam (Netherlands); Lammertsma, A.A.; Kuijk, C. van; Raijmakers, P.G. [VU University Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands)

    2015-09-15

    Epicardial adipose tissue (EAT) has been linked to coronary artery disease (CAD) and coronary microvascular dysfunction. However, its injurious effect may also impact the underlying myocardium. This study aimed to determine the impact of obesity on the quantitative relationship between left ventricular mass (LVM), EAT and coronary microvascular function. A total of 208 (94 men, 45 %) patients evaluated for CAD but free of coronary obstructions underwent quantitative [{sup 15}O]H{sub 2}O hybrid positron emission tomography (PET)/CT imaging. Coronary microvascular resistance (CMVR) was calculated as the ratio of mean arterial pressure to hyperaemic myocardial blood flow. Obese patients [body mass index (BMI) > 25, n = 133, 64 % of total] had more EAT (125.3 ± 47.6 vs 93.5 ± 42.1 cc, p < 0.001), a higher LVM (130.1 ± 30.4 vs 114.2 ± 29.3 g, p < 0.001) and an increased CMVR (26.6 ± 9.1 vs 22.3 ± 8.6 mmHg x ml{sup -1} x min{sup -1} x g{sup -1}, p < 0.01) as compared to nonobese patients. Male gender (β = 40.7, p < 0.001), BMI (β = 1.61, p < 0.001), smoking (β = 6.29, p = 0.03) and EAT volume (β = 0.10, p < 0.01) were identified as independent predictors of LVM. When grouped according to BMI status, EAT was only independently associated with LVM in nonobese patients. LVM, hypercholesterolaemia and coronary artery calcium score were independent predictors of CMVR. EAT volume is associated with LVM independently of BMI and might therefore be a better predictor of cardiovascular risk than BMI. However, EAT volume was not related to coronary microvascular function after adjustments for LVM and traditional risk factors. (orig.)

  14. Research on Blood Emergency Scheduling Optimization under Supply Disruption after Disasters%考虑供应中断的灾后安全救援血液优化调度研究

    Institute of Scientific and Technical Information of China (English)

    秦晓燕; 刘晓; 程勤侦

    2012-01-01

    血液应急保障是灾后安全救援的重要环节.为既有效满足需求,又避免盲目、过量的采血、调血增大血液过期报废压力甚至血荒的发生,保障灾后安全救援顺利进行,针对血液的易腐特性,提出血液应急调度的特点,并建立在物联网技术支持下的多时段、多类型血制品、多种运输方式的优化调度模型,通过合理调用库存血,组织自采血、外调血,并确定相应的数量以满足用血需求,实现血液应急保障系统响应时间和调度总成本最小化目标.采用ILOG CPLEX软件对模型进行求解,结合汶川特大地震的实际案例,进行数值仿真与结果分析,并给出在不同中断情景下的调度策略,表明通过建立双向互调的血液供应网络,并采用调度优化方法能够以更短的时间满足用血需求,同时减小调配成本和血液报废压力,能更好地应对灾后救援中出现的供应中断情况.%Blood emergency guarantee system plays an important role in the disaster relief. However, large fluctuation in blood demand makes precise forecast impossible, meanwhile, node failure and road resistance cause supply disruption. So in order to meet the demand and avoid great discard pressure caused by severe excess, even blood supply shortage after disaster relief, a multi-period, multi-commodity, multi-mode transportation model was developed, based on blood characteristics, analysis of blood emergency scheduling features and technology of Internet of Things, with an objective to minimize the total response time and emergency cost of the blood scheduling network as well as reduce the discard risk, by determining the amount of self-collection, transportation and inventory to meet the demand. ILOG CPLEX software was employed to resolve the model and gave scheduling strategies for different scenarios of supply disruption. With Wenchuan earthquake as an example, a numerical simulation was conducted, and the analysis results show

  15. Microvascular responsiveness in obesity: implications for therapeutic intervention

    OpenAIRE

    Bagi Zsolt (1974-) (orvos); Fehér Attila (Szeged); Cassuto, James

    2012-01-01

    Obesity has detrimental effects on the microcirculation. Functional changes in microvascular responsiveness may increase the risk of developing cardiovascular complications in obese patients. Emerging evidence indicates that selective therapeutic targeting of the microvessels may prevent life-threatening obesity-related vascular complications, such as ischaemic heart disease, heart failure and hypertension. It is also plausible that alterations in adipose tissue microcirculation contribute to...

  16. Repeat microvascular decompression for recurrent idiopathic trigeminal neuralgia

    NARCIS (Netherlands)

    Bakker, Nicolaas A.; van Dijk, J. Marc C.; Immenga, Steven; Wagemakers, Michiel; Metzemaekers, Jan D. M.

    2014-01-01

    Object. Microvascular decompression (MVD) is considered the method of choice to treat idiopathic trigeminal neuralgia (TN) refractory to medical treatment. However, repeat MVD for recurrent TN is not well established. In this paper, the authors describe a large case series in which patients underwen

  17. Vitamin D and retinal microvascular damage: The Rotterdam Study

    NARCIS (Netherlands)

    Mutlu, U.; Ikram, M.A.; Hofman, A.; Jong, P.T.; Uitterlinden, A.G.; Klaver, C.C.W.; Ikram, M.K.

    2016-01-01

    Vitamin D has been linked to various cardiovascular risk factors including indices of large-vessel disease. However, it remains unclear whether vitamin D is also associated with microvascular damage. In a community-dwelling population, we studied associations between vitamin D serum levels and

  18. Renal and cardiac microvascular endothelium: injury and repair

    NARCIS (Netherlands)

    Oosterhuis, NR

    2016-01-01

    Injury to the capillary endothelium can be devastating for renal and cardiac function. To halt the progression of chronic kidney disease (CKD) and heart failure (HF) preservation of the microvascular endothelial cell (EC) function and structure is of great importance.1 Increasing knowledge about

  19. Repeat microvascular decompression for recurrent idiopathic trigeminal neuralgia

    NARCIS (Netherlands)

    Bakker, Nicolaas A.; van Dijk, J. Marc C.; Immenga, Steven; Wagemakers, Michiel; Metzemaekers, Jan D. M.

    2014-01-01

    Object. Microvascular decompression (MVD) is considered the method of choice to treat idiopathic trigeminal neuralgia (TN) refractory to medical treatment. However, repeat MVD for recurrent TN is not well established. In this paper, the authors describe a large case series in which patients

  20. Vitamin D and retinal microvascular damage : The Rotterdam Study

    NARCIS (Netherlands)

    Mutlu, Unal; Ikram, M Arfan; Hofman, Albert; de Jong, Paulus T V M; Uitterlinden, Andre G; Klaver, Caroline C W; Ikram, M Kamran

    2016-01-01

    Vitamin D has been linked to various cardiovascular risk factors including indices of large-vessel disease. However, it remains unclear whether vitamin D is also associated with microvascular damage. In a community-dwelling population, we studied associations between vitamin D serum levels and retin

  1. Renal and cardiac microvascular endothelium: injury and repair

    NARCIS (Netherlands)

    Oosterhuis, N.R.

    2016-01-01

    Injury to the capillary endothelium can be devastating for renal and cardiac function. To halt the progression of chronic kidney disease (CKD) and heart failure (HF) preservation of the microvascular endothelial cell (EC) function and structure is of great importance.1 Increasing knowledge about mic

  2. Modeling of microvascular permeability changes after electroporation.

    Directory of Open Access Journals (Sweden)

    Selma Corovic

    Full Text Available Vascular endothelium selectively controls the transport of plasma contents across the blood vessel wall. The principal objective of our preliminary study was to quantify the electroporation-induced increase in permeability of blood vessel wall for macromolecules, which do not normally extravasate from blood into skin interstitium in homeostatic conditions. Our study combines mathematical modeling (by employing pharmacokinetic and finite element modeling approach with in vivo measurements (by intravital fluorescence microscopy. Extravasation of fluorescently labeled dextran molecules of two different sizes (70 kDa and 2000 kDa following the application of electroporation pulses was investigated in order to simulate extravasation of therapeutic macromolecules with molecular weights comparable to molecular weight of particles such as antibodies and plasmid DNA. The increase in blood vessel permeability due to electroporation and corresponding transvascular transport was quantified by calculating the apparent diffusion coefficients for skin microvessel wall (D [μm2/s] for both molecular sizes. The calculated apparent diffusion coefficients were D = 0.0086 μm2/s and D = 0.0045 μm2/s for 70 kDa and 2000 kDa dextran molecules, respectively. The results of our preliminary study have important implications in development of realistic mathematical models for prediction of extravasation and delivery of large therapeutic molecules to target tissues by means of electroporation.

  3. Modeling of microvascular permeability changes after electroporation.

    Science.gov (United States)

    Corovic, Selma; Markelc, Bostjan; Dolinar, Mitja; Cemazar, Maja; Jarm, Tomaz

    2015-01-01

    Vascular endothelium selectively controls the transport of plasma contents across the blood vessel wall. The principal objective of our preliminary study was to quantify the electroporation-induced increase in permeability of blood vessel wall for macromolecules, which do not normally extravasate from blood into skin interstitium in homeostatic conditions. Our study combines mathematical modeling (by employing pharmacokinetic and finite element modeling approach) with in vivo measurements (by intravital fluorescence microscopy). Extravasation of fluorescently labeled dextran molecules of two different sizes (70 kDa and 2000 kDa) following the application of electroporation pulses was investigated in order to simulate extravasation of therapeutic macromolecules with molecular weights comparable to molecular weight of particles such as antibodies and plasmid DNA. The increase in blood vessel permeability due to electroporation and corresponding transvascular transport was quantified by calculating the apparent diffusion coefficients for skin microvessel wall (D [μm2/s]) for both molecular sizes. The calculated apparent diffusion coefficients were D = 0.0086 μm2/s and D = 0.0045 μm2/s for 70 kDa and 2000 kDa dextran molecules, respectively. The results of our preliminary study have important implications in development of realistic mathematical models for prediction of extravasation and delivery of large therapeutic molecules to target tissues by means of electroporation.

  4. Intraoperative microvascular Doppler monitoring in intracranial aneurysm surgery

    Institute of Scientific and Technical Information of China (English)

    HUI Pin-jing; YAN Yan-hong; ZHANG Shi-ming; WANG Zhong; YU Zheng-quan; ZHOU You-xin; LI Xiang-dong

    2013-01-01

    Background Surgical treatment of intracranial aneurysms is often compromised by incomplete exclusion of the aneurysm or stenosis of parent vessels.Intraoperative microvascular Doppler (IMD) is an attractive,noninvasive,and inexpensive tool.The present study aimed to evaluate the usefulness and reliability of IMD for guiding clip placement in aneurysm surgery.Methods A total of 92 patients with 101 intracranial aneurysms were included in the study.IMD with a 1.5-mm diameter,20-MHz microprobe was used before and after clip application to confirm aneurysm obliteration and patency of parent vessels and branching arteries.IMD findings were verified postoperatively with digital subtraction angiography (DSA) or dual energy computed tomography angiography (DE-CTA).Ninety consecutive patients,harboring 108 aneurysms,who underwent surgery without IMD was considered as the control group.Results The microprobe detected all vessels of the Circle of Willis and their major branches.Clips were repositioned in 24 (23.8%) aneurysms on the basis of the IMD findings consistent with incomplete exclusion and/or stenosis.IMD identified persistent weak blood flow through the aneurismal sac of 11 of the 101 (10.9%) aneurysms requiring clip adjustment.Stenosis or occlusion of the parent or branching arteries as indicated by IMD necessitated immediate clip adjustment in 19 aneurysms (18.8%).The mean duration of the IMD procedure was 4.8 minutes.The frequency of clip adjustment (mean:1.8 times per case) was associated with the size and location of the aneurysm.There were no complications related to the use of IMD,and postoperative angiograms confirmed complete aneurysm exclusion and parent vessel patency.About 8.3% (9/108) aneurysms were unexpectedly incompletely occluded,and 10.2% (11/108) aneurysms and parent vessel stenosis without IMD were detected by postoperative DSA or DE-CTA.IMD could reduce the rate of residual aneurysm and unanticipated vessel stenosis which demonstrated

  5. Intensive blood pressure control affects cerebral blood flow in type 2 diabetes mellitus patients

    DEFF Research Database (Denmark)

    Kim, Yu-Sok; Davis, Shyrin C A T; Truijen, Jasper;

    2011-01-01

    Type 2 diabetes mellitus is associated with microvascular complications, hypertension, and impaired dynamic cerebral autoregulation. Intensive blood pressure (BP) control in hypertensive type 2 diabetic patients reduces their risk of stroke but may affect cerebral perfusion. Systemic hemodynamic...... variables and transcranial Doppler-determined cerebral blood flow velocity (CBFV), cerebral CO2 responsiveness, and cognitive function were determined after 3 and 6 months of intensive BP control in 17 type 2 diabetic patients with microvascular complications (T2DM+), in 18 diabetic patients without (T2DM......-) microvascular complications, and in 16 nondiabetic hypertensive patients. Cerebrovascular reserve capacity was lower in T2DM+ versus T2DM- and nondiabetic hypertensive patients (4.6±1.1 versus 6.0±1.6 [P

  6. The brain microvascular endothelium supports T cell proliferation and has potential for alloantigen presentation.

    Directory of Open Access Journals (Sweden)

    Julie Wheway

    Full Text Available Endothelial cells (EC form the inner lining of blood vessels and are positioned between circulating lymphocytes and tissues. Hypotheses have formed that EC may act as antigen presenting cells based on the intimate interactions with T cells, which are seen in diseases like multiple sclerosis, cerebral malaria (CM and viral neuropathologies. Here, we investigated how human brain microvascular EC (HBEC interact with and support the proliferation of T cells. We found HBEC to express MHC II, CD40 and ICOSL, key molecules for antigen presentation and co-stimulation and to take up fluorescently labeled antigens via macropinocytosis. In co-cultures, we showed that HBEC support and promote the proliferation of CD4(+ and CD8(+ T cells, which both are key in CM pathogenesis, particularly following T cell receptor activation and co-stimulation. Our findings provide novel evidence that HBEC can trigger T cell activation, thereby providing a novel mechanism for neuroimmunological complications of infectious diseases.

  7. The Microvascular Gap Junction Channel: A Route to Deliver MicroRNAs for Neurological Disease Treatment.

    Science.gov (United States)

    Thuringer, Dominique; Solary, Eric; Garrido, Carmen

    2017-01-01

    Brain microvascular endothelial cells (BMECs) separate the peripheral blood from the brain. These cells, which are surrounded by basal lamina, pericytes and glial cells, are highly interconnected through tight and gap junctions. Their permeability properties restrict the transfer of potentially useful therapeutic agents. In such a hermetic system, the gap junctional exchange of small molecules between cerebral endothelial and non-endothelial cells is crucial for maintaining tissue homeostasis. MicroRNA were shown to cross gap junction channels, thereby modulating gene expression and function of the recipient cell. It was also shown that, when altered, BMEC could be regenerated by endothelial cells derived from pluripotent stem cells. Here, we discuss the transfer of microRNA through gap junctions between BMEC, the regeneration of BMEC from induced pluripotent stem cells that could be engineered to express specific microRNA, and how such an innovative approach could benefit to the treatment of glioblastoma and other neurological diseases.

  8. The Microvascular Gap Junction Channel: A Route to Deliver MicroRNAs for Neurological Disease Treatment

    Directory of Open Access Journals (Sweden)

    Dominique Thuringer

    2017-08-01

    Full Text Available Brain microvascular endothelial cells (BMECs separate the peripheral blood from the brain. These cells, which are surrounded by basal lamina, pericytes and glial cells, are highly interconnected through tight and gap junctions. Their permeability properties restrict the transfer of potentially useful therapeutic agents. In such a hermetic system, the gap junctional exchange of small molecules between cerebral endothelial and non-endothelial cells is crucial for maintaining tissue homeostasis. MicroRNA were shown to cross gap junction channels, thereby modulating gene expression and function of the recipient cell. It was also shown that, when altered, BMEC could be regenerated by endothelial cells derived from pluripotent stem cells. Here, we discuss the transfer of microRNA through gap junctions between BMEC, the regeneration of BMEC from induced pluripotent stem cells that could be engineered to express specific microRNA, and how such an innovative approach could benefit to the treatment of glioblastoma and other neurological diseases.

  9. Microvascular injury and the kidney in hypertension.

    Science.gov (United States)

    Ruiz-Hurtado, G; Ruilope, L M

    2017-04-18

    Renal macrocirculation participates in the development of arterial hypertension. The elevation in systemic blood pressure (BP) can damage the kidney starting in the microcirculation. Established arterial hypertension impinge upon the large arteries and stiffness develops. As a consequence central BP raises and BP pulsatility appear and contribute to further damage renal microcirculation by direct transmission of the elevated BP. Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Role of microcomputed tomography in microvascular imaging

    Science.gov (United States)

    Ritman, Erik L.

    2011-03-01

    Micro-CT scans generate three-dimensional images consisting of the order of 10003 voxels (3D picture elements), each cubic voxel being sub-micron to 100 micrometer on a side. The gray-scale modulation within tomographic images reflects the local attenuation of the x-ray. This allows for differentiation of different tissues by virtue of their elemental content. However, the elements in blood vessel walls and within blood differ little from organ parenchyma, hence they are not readily distinguishable unless the attenuation of blood is enhanced by injecting a heavy element (such as iodine) into the blood stream or by staining the vessel wall tissues with heavy metals such as osmium tetroxide. Three-dimensional micro-CT images a volume (of light-opaque tissue) large enough to include entire, intact, vascular trees without the need to destroy the 3D tissue specimen. Hence, the fluid dynamic and the perfusion territory size consequences, as well the micro-anatomic relationship of the vascular branching geometry and interconnectivity to parenchymal structures (e.g., nephron, hepatic lobule or cancer) can be readily appreciated and quantified. The permeability of microvasculature can also be imaged by virtue of the increased contrast resulting from the fraction of the injected contrast agent passing through the endothelium into the surrounding extravascular tissue. In recent years micro-CT based on the imaging of coherent x-ray scatter and on x-ray phase shift caused by local electron density distributions (reflecting molecular bond type in some cases) provide greater inherent image contrast than does x-ray attenuation. These new capabilities are now active avenues of research and development.

  11. Diminished Alveolar Microvascular Reserves in Type 2 Diabetes Reflect Systemic Microangiopathy

    Science.gov (United States)

    Chance, William W.; Rhee, Chanhaeng; Yilmaz, Cuneyt; Dane, D. Merrill; Pruneda, M. Lourdes; Raskin, Philip; Hsia, Connie C.W.

    2008-01-01

    OBJECTIVE—Alveolar microvascular function is moderately impaired in type 1 diabetes, as manifested by restriction of lung volume and diffusing capacity (DLCO). We examined whether similar impairment develops in type 2 diabetes and defined the physiologic sources of impairment as well as the relationships to glycemia and systemic microangiopathy. RESEARCH DESIGN AND METHODS—A cross-sectional study was conducted at a university-affiliated diabetes treatment center and outpatient diabetes clinic, involving 69 nonsmoking type 2 diabetic patients without overt cardiopulmonary disease. Lung volume, pulmonary blood flow (Q̇), DLCO, membrane diffusing capacity (measured from nitric oxide uptake [DLNO]), and pulmonary capillary blood volume (VC) were determined at rest and exercise for comparison with those in 45 healthy nonsmokers as well as with normal reference values. RESULTS—In type 2 diabetic patients, peak levels of oxygen uptake, Q̇ and DLCO, DLNO, and VC at exercise were 10–25% lower compared with those in control subjects. In nonobese patients (BMI DLNO, and VC were fully explained by the lower lung volume and peak Q̇, but these factors did not fully explain the impairment in obese patients (BMI >30 kg/m2). The slope of the increase in VC with respect to Q̇ was reduced ∼20% in patients regardless of BMI, consistent with impaired alveolar-capillary recruitment. Functional impairment was directly related to A1C level, retinopathy, neuropathy, and microalbuminuria in a sex-specific manner. CONCLUSIONS—Alveolar microvascular reserves are reduced in type 2 diabetes, reflecting restriction of lung volume, alveolar perfusion, and capillary recruitment. This reduction correlates with glycemic control and extrapulmonary microangiopathy and is aggravated by obesity. PMID:18492945

  12. 21 CFR 606.65 - Supplies and reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Supplies and reagents. 606.65 Section 606.65 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS CURRENT GOOD MANUFACTURING PRACTICE FOR BLOOD AND BLOOD COMPONENTS Equipment § 606.65 Supplies and reagents. All supplies and reagents used in...

  13. Melatonin reduces microvascular damage and insulin resistance in hamsters due to chronic intermittent hypoxia.

    Science.gov (United States)

    Bertuglia, Silvia; Reiter, Russel J

    2009-04-01

    Obstructive sleep apnea (OSA) causes intermittent hypoxia (IH) associated with hypertension, insulin resistance and a systemic inflammatory response. We evaluated the effects of melatonin on vasodilation, capillary perfusion in hamster cheek pouch and insulin resistance, hypertension, and reactive oxygen species (ROS) and nitrate/nitrite levels after IH for 4 wk. Syrian hamsters were divided into four groups: control group (CON), IH group, and melatonin (10 mg/kg) intraperitoneally administered daily for 4 wk/30 min before intermittent air (MEL) or IH (IH + MEL) exposure. IH alone caused elevated blood pressure, increased hematocrit, fasting hyperglycemia, elevated ROS and nitrite/nitrate levels, and vasoconstriction and reduced microvascular perfusion. Melatonin treatment of IH-exposed animals decreased blood pressure, blood glucose, and ROS and nitrite/nitrate levels, and increased vasodilation and capillary perfusion. An oral glucose tolerance test was performed after 4 wk of IH. During the last 30 min of the hyperinsulinemic euglycemic clamp, blood glucose, and insulin levels were identically matched between groups, but the glucose infusion rate was significantly reduced in IH (29.9 +/- 1.9 mg/kg/min) versus IH + MEL group (45.4 +/- 1.5 mg/kg/min, P melatonin. In conclusion, protection induced by melatonin against functional and metabolic impairment in IH is related to the regulation of ROS and nitrite/nitrate levels in the microcirculation. These observations may have importance to OSA pathological changes.

  14. The Trp64Arg amino acid polymorphism of the beta3-adrenergic receptor gene does not contribute to the genetic susceptibility of diabetic microvascular complications in Caucasian type 1 diabetic patients

    DEFF Research Database (Denmark)

    Tarnow, L; Urhammer, S A; Mottlau, B

    1999-01-01

    OBJECTIVE: The beta3-adrenergic receptor is involved in regulation of microvascular blood flow. A missense mutation (Trp64Arg) in the beta3-adrenergic receptor gene has been suggested as a risk factor for proliferative retinopathy in Japanese type 2 diabetic patients. The aim of the present study...

  15. Tainted blood

    DEFF Research Database (Denmark)

    Deleuran, Ida; Sheikh, Zainab Afshan; Hoeyer, Klaus

    2015-01-01

    study of the historical rise and current workings of safety practices in the Danish blood system. Here, we identify a strong focus on contamination in order to avoid 'tainted blood', at the expense of working with risks that could be avoided through enhanced blood monitoring practices. Of further...... significance to this focus are the social dynamics found at the heart of safety practices aimed at avoiding contamination. We argue that such dynamics need more attention, in order to achieve good health outcomes in transfusion medicine. Thus, we conclude that, to ensure continuously safe blood systems, we...... need to move beyond the bifurcation of the social and medical aspects of blood supply as two separate issues and approach social dynamics as key medical safety questions....

  16. Radiochemotherapy-induced changes of tumour vascularity and blood supply estimated by dynamic contrast-enhanced CT and fractal analysis in malignant head and neck tumours.

    Science.gov (United States)

    Abramyuk, A; Hietschold, V; Appold, S; von Kummer, R; Abolmaali, N

    2015-01-01

    To investigate radiochemotherapy (RChT)-induced changes of transfer coefficient (K(trans)) and relative tumour blood volume (rTBV) estimated by dynamic contrast-enhanced CT (DCE-CT) and fractal analysis in head and neck tumours (HNTs). DCE-CT was performed in 15 patients with inoperable HNTs before RChT, and after 2 and 5 weeks. The dynamics of K(trans) and rTBV as well as lacunarity, slope of log(lacunarity) vs log(box size), and fractal dimension were compared with tumour behaviour during RChT and in the 24-month follow-up. In 11 patients, an increase of K(trans) and/or rTBV after 20 Gy followed by a decrease of both parameters after 50 Gy was noted. Except for one local recurrence, no tumour residue was found during the follow-up. In three patients with partial tumour reduction during RChT, a decrease of K(trans) accompanied by an increase in rTBV between 20 and 50 Gy was detected. In one patient with continuous elevation of both parameters, tumour progressed after RChT. Pre-treatment difference in intratumoral heterogeneity with its decline under RChT for the responders vs non-responders was observed. Initial growth of K(trans) and/or rTBV followed by further reduction of both parameters along with the decline of the slope of log(lacunarity) vs log(box size) was associated with positive radiochemotherapeutic response. Increase of K(trans) and/or rTBV under RChT indicated a poor outcome. The modification of K(trans) and rTBV as measured by DCE-CT may be applied for the assessment of tumour sensitivity to chose RChT regimen and, consequently, to reveal clinical impact allowing individualization of RChT strategy in patients with HNT.

  17. Treatment of Angina Pectoris Associated with Coronary Microvascular Dysfunction.

    Science.gov (United States)

    Ong, Peter; Athanasiadis, Anastasios; Sechtem, Udo

    2016-08-01

    Treatment of angina pectoris associated with coronary microvascular dysfunction is challenging as the underlying mechanisms are often diverse and overlapping. Patients with type 1 coronary microvascular dysfunction (i.e. absence of epicardial coronary artery disease and myocardial disease) should receive strict control of their cardiovascular risk factors and thus receive statins and ACE-inhibitors in most cases. Antianginal medication consists of ß-blockers and/or calcium channel blockers. Second line drugs are ranolazine and nicorandil with limited evidence. Despite individually titrated combinations of these drugs up to 30 % of patients have refractory angina. Rho-kinase inhibitors and endothelin-receptor antagonists represent potential drugs that may prove useful in these patients in the future.

  18. Microvascular retinopathy in subjects without diabetes

    DEFF Research Database (Denmark)

    Munch, Inger Christine; Kessel, Line; Borch-Johnsen, Knut

    2012-01-01

    tolerance testing, clinical and laboratory examinations, non-invasive ocular lens fluorometry and seven-field fundus photography. Results: Retinopathy was present in 8.3% (CI(95) 6.3-10.3%) of subjects. Higher systolic blood pressure (SBP) (p = 0.032), increasing body mass index (BMI) (p = 0.014) and wider......Purpose: Retinal vascular lesions such as microaneurysms and haemorrhages, while typical of diabetic retinopathy, are also seen in subjects without diabetes where they are associated with elevated cardiovascular mortality. In theory, these lesions could be a consequence of past hyperglycaemia. We...... examined the prevalence and risk factors for retinopathy, including lens fluorescence, a biomarker of cumulative life-time glycaemia in adults without diabetes. Methods: Cross-sectional population-based study of 711 subjects without diabetes (WHO 1999 criteria) aged 30-60 years, including oral glucose...

  19. Cell proliferation along vascular islands during microvascular network growth

    Directory of Open Access Journals (Sweden)

    Kelly-Goss Molly R

    2012-06-01

    Full Text Available Abstract Background Observations in our laboratory provide evidence of vascular islands, defined as disconnected endothelial cell segments, in the adult microcirculation. The objective of this study was to determine if vascular islands are involved in angiogenesis during microvascular network growth. Results Mesenteric tissues, which allow visualization of entire microvascular networks at a single cell level, were harvested from unstimulated adult male Wistar rats and Wistar rats 3 and 10 days post angiogenesis stimulation by mast cell degranulation with compound 48/80. Tissues were immunolabeled for PECAM and BRDU. Identification of vessel lumens via injection of FITC-dextran confirmed that endothelial cell segments were disconnected from nearby patent networks. Stimulated networks displayed increases in vascular area, length density, and capillary sprouting. On day 3, the percentage of islands with at least one BRDU-positive cell increased compared to the unstimulated level and was equal to the percentage of capillary sprouts with at least one BRDU-positive cell. At day 10, the number of vascular islands per vascular area dramatically decreased compared to unstimulated and day 3 levels. Conclusions These results show that vascular islands have the ability to proliferate and suggest that they are able to incorporate into the microcirculation during the initial stages of microvascular network growth.

  20. Delayed, bilateral, non-microvascular ear replantation after violent amputation.

    Science.gov (United States)

    García-Murray, E; Adán-Rivas, O; Salcido-Calzadilla, H

    2009-06-01

    Amputation of any body part is undoubtedly a traumatic experience leaving a terrible deformity, especially when the part or parts involved are visible and constitute an essential component of someone's facial whole. Bilateral ear amputation and successful subsequent replantation has been reported historically, but not in the modern surgical literature. We report the case of a 27-year-old female who was abducted and suffered a bilateral ear amputation at the hands of one of her captors to speed delivery of ransom money; the severed parts were sent to the parents approximately 2 hours after the amputation had taken place, and the girl was released some 48 hours after the ears were delivered. Microvascular replantation was attempted immediately after admission to the hospital some 2 hours after her release, but failed, and so a non-microvascular replantation was performed and was successful, after approximately 54 hours of ischaemia time. We consider this the first report of a complete bilateral, delayed, non-microvascular, successful ear replantation in a human being in the modern literature.

  1. Antiproliferative effect of elevated glucose in human microvascular endothelial cells

    Science.gov (United States)

    Kamal, K.; Du, W.; Mills, I.; Sumpio, B. E.

    1998-01-01

    Diabetic microangiopathy has been implicated as a fundamental feature of the pathological complications of diabetes including retinopathy, neuropathy, and diabetic foot ulceration. However, previous studies devoted to examining the deleterious effects of elevated glucose on the endothelium have been performed largely in primary cultured cells of macrovessel origin. Difficulty in the harvesting and maintenance of microvascular endothelial cells in culture have hindered the study of this relevant population. Therefore, the objective of this study was to characterize the effect of elevated glucose on the proliferation and involved signaling pathways of an immortalized human dermal microvascular endothelial cell line (HMEC-1) that possess similar characteristics to their in vivo counterparts. Human dermal microvascular endothelial cells (HMEC-1) were grown in the presence of normal (5 mM) or high D-glucose (20 mM) for 14 days. The proliferative response of HMEC-1 was compared under these conditions as well as the cAMP and PKC pathways by in vitro assays. Elevated glucose significantly inhibited (P diabetic microangiopathy.

  2. [Microvascular anastomoses in reconstructive head and neck surgery].

    Science.gov (United States)

    Remmert, S

    1995-04-01

    At the ENT Department of the University of Lübeck, 57 microvascular tissue transplants with 129 anastomoses (61 arterial and 68 venous) have been performed in the last three years. Arteries have always been anastomosed end to end. The venous anastomoses have primarily been performed as end-to-side unions with the jugular vein. In nine patients, great distances between the donor and recipient vessel had to be connected with venous interponates. In two cases in which veins were lacking in the neck after radical neck dissection or radiation fibrosis, we used the cephalic vein or veins of the capsule of the thyroid gland as recipient vessels. The jejunal or osteomyocutaneous transplants were first fitted into the defect before performing the anastomosis. The jejunal peristalsis and the required freedom of movement in shaping the bone necessitated this technique. Microvascular anastomosis was first performed on the transplant of the radialis flap and the neurovascular infrahyoid muscular flap, and then they were integrated into the defect. We lost two transplants postoperatively because of venous thrombosis. In this article wie describe our anastomosis technique, the frequency distribution of recipient vessels, and the rules and characteristics of microvascular anastomosis after radiation and neck dissection.

  3. Microfabrication of cylindrical microfluidic channel networks for microvascular research.

    Science.gov (United States)

    Huang, Zhouchun; Li, Xiang; Martins-Green, Manuela; Liu, Yuxin

    2012-10-01

    Current methods for formation of microvascular channel scaffolds are limited with non-circular channel cross-sections, complicated fabrication, and less flexibility in microchannel network design. To address current limitations in the creation of engineered microvascular channels with complex three-dimensional (3-D) geometries in the shape of microvessels, we have developed a reproducible, cost-effective, and flexible micromanufacturing process combined with photolithographic reflowable photoresist and soft lithography techniques to fabricate cylindrical microchannel and networks. A positive reflowable photoresist AZ P4620 was used to fabricate a master microchannel mold with semi-circular cross-sections. By the alignment and bonding of two polydimethylsiloxane (PDMS) microchannels replicated from the master mold together, a cylindrical microchannel or microchannel network was created. Further examination of the channel dimensions and surface profiles at different branching levels showed that the shape of the microfluidic channel was well approximated by a semi-circular surface, and a multi-level, multi-depth channel network was created. In addition, a computational fluidic dynamics (CFD) model was used to simulate shear flows and corresponding pressure distributions inside of the microchannel and channel network based on the dimensions of the fabricated channels. The fabricated multi-depth cylindrical microchannel network can provide platforms for the investigation of microvascular cells growing inside of cylindrical channels under shear flows and lumen pressures, and work as scaffolds for the investigation of morphogenesis and tubulogenesis.

  4. Early experiences with microvascular free tissue transfer in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Bolaji O Mofikoya

    2014-01-01

    Full Text Available Objectives: Microvascular free tissue transfer within our subregion is fraught with considerable challenges. We aim to highlight our experiences gained with our first fifteen cases of microvascular free tissue transfer at the Lagos University Teaching Hospital. We believe our report will be useful to colleagues embarking on such reconstructions in similar settings. Materials and Methods: The clinical records of the first 15 cases of free flaps done at our center were reviewed. The indications for surgery, choice of flap, recipient vessels, duration of surgery and complications were noted. Results: Fifteen cases were done, 10 flaps survived, ten defects occurred following trauma while remaining five followed cancer resections. Anterolateral thigh and radial forearm flaps were the most common flap used. The mean duration of surgeries was 7.1 hours SD ± 1.10 hours. Our take back rate was 13.3%, with a salvage rate of 50%. Three flaps failed on account venous congestion while remaining two failed due to arterial occlusion. Conclusion: 66.67% free flap success rate recorded reflect our early experiences in our institution. We believe meticulous planning, careful vessel selection, close flap monitoring as well as improved infrastructural support can lead to much better success rates in microvascular reconstruction in our country.

  5. Evaluation of gravimetric techniques to estimate the microvascular filtration coefficient.

    Science.gov (United States)

    Dongaonkar, R M; Laine, G A; Stewart, R H; Quick, C M

    2011-06-01

    Microvascular permeability to water is characterized by the microvascular filtration coefficient (K(f)). Conventional gravimetric techniques to estimate K(f) rely on data obtained from either transient or steady-state increases in organ weight in response to increases in microvascular pressure. Both techniques result in considerably different estimates and neither account for interstitial fluid storage and lymphatic return. We therefore developed a theoretical framework to evaluate K(f) estimation techniques by 1) comparing conventional techniques to a novel technique that includes effects of interstitial fluid storage and lymphatic return, 2) evaluating the ability of conventional techniques to reproduce K(f) from simulated gravimetric data generated by a realistic interstitial fluid balance model, 3) analyzing new data collected from rat intestine, and 4) analyzing previously reported data. These approaches revealed that the steady-state gravimetric technique yields estimates that are not directly related to K(f) and are in some cases directly proportional to interstitial compliance. However, the transient gravimetric technique yields accurate estimates in some organs, because the typical experimental duration minimizes the effects of interstitial fluid storage and lymphatic return. Furthermore, our analytical framework reveals that the supposed requirement of tying off all draining lymphatic vessels for the transient technique is unnecessary. Finally, our numerical simulations indicate that our comprehensive technique accurately reproduces the value of K(f) in all organs, is not confounded by interstitial storage and lymphatic return, and provides corroboration of the estimate from the transient technique.

  6. 单侧完全性唇腭裂胎儿颌面部血供的应用解剖%Applied anatomy of the maxillofacial region's blood supply in unilateral complete cleft lip and palate fetus

    Institute of Scientific and Technical Information of China (English)

    黄海龙; 邓健全; 陈丽娟; 钟卫娟; 梁恩来

    2013-01-01

    Objective To provide anatomic basis of intrauterine surgical repair in unilateral complete cleft lip and palate fetus. Methods The head and neck vascular cast specimens of 21-32 weeks normal and unilateral complete cleft lip and palate were made and observed, which maxillofacial region's blood supply source and arterial anastomosis were compared. Results ①For the normal fetus, the maxillofacial region' s blood supply mainly came from facial artery, submental artery, inferior labial artery, superior labial artery, lower edge nasal alar artery, nasal alar artery, lateral nasal artery, dorsal nasal artery, infraorbiatal artery and transverse facial artery, which to build the rich vascular network. ②For the fetus with unilateral complete cleft lip and palate, the affected side of superior labial artery walked along cleft border up to the anastomosis with lower edge nasal alar artery by the basis of nasal alar artery. The affected side of greater palatine artery and nasal vessel were formd in the anastomosis by bone stump. Conclusion When the intrauterine surgical repair of unilateral complete cleft lip and palate is performed, the emphasis of blood supply are on the nose and upper lip region, which are mainly in superior labial artery, lower edge nasal alar artery and greater palatine artery.%目的 为单侧完全性唇腭裂胎儿宫内手术修复提供解剖学基础.方法 制作和观察21~32周正常和单侧完全性唇腭裂胎儿头颈部血管铸型标本,比较它们颌面部血供的来源及吻合情况.结果 ①正常胎儿颌面部血供主要来源于面动脉、颏下动脉、下唇动脉、上唇动脉、鼻翼下缘动脉、鼻翼动脉、鼻外侧动脉、鼻背动脉、眶下动脉及面横动脉等,这些动脉及其分支构筑颌面部组织丰富的血管网;②单侧完全性唇腭裂胎儿患侧上唇动脉沿裂缘向上至鼻翼基底部与鼻翼下缘动脉等相吻合,患侧部分腭骨缺损暴露的腭大动脉穿过骨残端

  7. Perfusion MRI derived indices of microvascular shunting and flow control correlate with tumor grade and outcome in patients with cerebral glioma.

    Directory of Open Access Journals (Sweden)

    Anna Tietze

    Full Text Available Deficient microvascular blood flow control is thought to cause tumor hypoxia and increase resistance to therapy. In glioma patients, we tested whether perfusion-weighted MRI (PWI based indices of microvascular flow control provide more information on tumor grade and patient outcome than does the established PWI angiogenesis marker, cerebral blood volume (CBV.Seventy-two glioma patients (sixty high-grade, twelve low-grade gliomas were included. Capillary transit time heterogeneity (CTH and the coefficient of variation (COV, its ratio to blood mean transit time, provide indices of microvascular flow control and the extent to which oxygen can be extracted by tumor tissue. The ability of these parameters and CBV to differentiate tumor grade were assessed by receiver operating characteristic curves and logistic regression. Their ability to predict time to progression and overall survival was examined by the Cox proportional-hazards regression model, and by survival curves using log-rank tests.The best prediction of grade (AUC = 0.876; p < 0.05 was achieved by combining knowledge of CBV and CTH in the enhancing tumor and peri-focal edema, and patients with glioblastoma multiforme were identified best by CTH (AUC = 0.763; p<0.001. CTH outperformed CBV and COV in predicting time to progression and survival in all gliomas and in a subgroup consisting of only high-grade gliomas.Our study confirms the importance of microvascular flow control in tumor growth by demonstrating that determining CTH improves tumor grading and outcome prediction in glioma patients compared to CBV alone.

  8. Selective microvascular muscle perfusion imaging in the shoulder with intravoxel incoherent motion (IVIM).

    Science.gov (United States)

    Nguyen, Audrey; Ledoux, Jean-Baptiste; Omoumi, Patrick; Becce, Fabio; Forget, Joachim; Federau, Christian

    2017-01-01

    The evaluation of local muscle recruitment during a specific movement can be done indirectly by measuring changes in local blood flow. Intravoxel incoherent motion perfusion imaging exploits some properties of the magnetic resonance to measure locally microvascular perfusion, and seems ideally suited for this task. We studied the selectivity of the increase in intravoxel incoherent motion blood flow related parameter fD* in the muscles of 24 shoulders after two physical exam maneuvers, Jobe and Lift-off test (test order reversed in half of the volunteers) each held 2min against resistance. After a lift-off, IVIM blood flow-related fD* was increased in the subscapularis (in 10(-3)mm(2)s(-1), 3.24±0.86 vs. rest 1.37±0.58, pmuscles and deltoid bundles respectively. After a Jobe test, increase in fD* was scattered within the rotator cuff muscles, but was selective for the lateral deltoid compared to the other deltoid bundles (anterior, pmuscle testing of the shoulder muscles with IVIM. This technique has the potential to non-invasively characterize perfusion-related musculoskeletal physiological as well as pathological processes. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. 静脉留置针在深部游离组织瓣移植中监测血供的临床应用%Clinical application of intravenous catheter in monitoring blood supply of deep free flap graft

    Institute of Scientific and Technical Information of China (English)

    胡广伟; 廖天安; 王鸿; 邱勋永

    2012-01-01

    目的:评价静脉留置针在深部游离组织瓣移植中监测血供的临床应用价值.方法:应用腓骨肌(皮)瓣、髂骨肌骨瓣、前臂皮瓣等游离移植修复组织缺损的病例共26例,年龄22~ 70岁,在深部游离组织瓣静脉远心端留置静脉针,术后通过静脉留置针输注低分子右旋糖酐,20ml/h,持续7天,并给予罂粟碱30mg肌肉注射,1次/8h,抗凝及扩血管处理.结果:7天内现测25例静脉留置针滴注通畅,有1例患者在术后48h内出现静脉留置针滴速变慢,给予灌注稀释肝素生理盐水后阻力恢复正常.26例深部组织瓣全部存活,未出现血管危象.结论:静脉留置针在深部游离组织瓣移植应用能持续监测组织瓣血管通畅状况,有效预防静脉血栓形成,提高组织瓣的成活率.%Objective To assess the clinical application value of intravenous catheter in monitoring blood supply of deep free flap graft. Methods 26 cases of tissue defects which were reconstructed by free radical fibular osteocutaneous flap,iliac osteomusculocutaneous flap,forearm flaps,the age from 22 to 70,were treated with intravenous catheter from distal vein of deep free flap by which intravenous drip dextran-40 were given,average 20 milliliter each hour and last 7 days.The patients were given narceine 30mg, intramuscular injection every 8 hour anticoagulation and vasodilator therapy by routine. Results Distal intravenous catheter of 25 cases kept fluent, and intravenous catheter of 1 case appeared slow,became normal after repeated infusion of dilute heparin saline.26 cases'deep free flaps were all survived without occurring vascular crisis. Conclusion Application of intravenous catheter in deep free flap graft can monitor blood supply of free flap continuously, prevent venous thrombosis effectively and improve flap survival.

  10. An evaluation of the efficacy of microvascular breast reconstruction techniques.

    Science.gov (United States)

    Dobrut, Mirosław; Maciejewski, Adam; Półtorak, Stanisław

    2013-01-01

    The aim of the study was to evaluate the efficacy of different microvascular techniques in breast reconstruction with the analysis of postoperative complications. The additional goal of the study is to analyze the quality of life of patients after microvascular breast reconstruction in comparison to the control group of patients who underwent only mastectomy without any reconstructive procedures. Also the algorithm of breast reconstruction is presented as the result of own experiences. Clinical material contain 2 groups of patients - women after surgical treatment in Department of Oncological and Reconstructive Surgery, Cancer Center in Gliwice in the year 2004-2009 where in 53 cases immediate and in 26 delayed breast microvascular reconstruction were performed. In all cases the diagnosis of cancer was proved by histopathological biopsy before the treatment. The type of radical resection (mastectomy) depended on histopathological type of cancer and its localization. The reconstruction - immediate vs delayed was carefully planned together with oncological treatment of the cases. Everywhere this plan was established based on carefully examinations of inferior epigastric vessels and theirs perforators. The choice between immediate and delayed microvascular reconstruction was based on prognosis and predictive factors. The QOL was analyzed due to own questionnaire when functional, aesthetics and social effects were evaluated. Free flap survival rate for all types of free flap was 95%. In cases where classic TRAM was used the rate was 85%, in cases where muscle sparring TRAM was chosen the survival rate was 100% and in remaining cases of DIEP reconstructions the rate was 89%. Generally the complications after microvascular reconstruction occurred in 13 cases (16%). In 9 cases the problems with flaps perfusion were notified. Total flap necrosis was observed in 2 TRAM and in 2 DIEP cases. In all those cases salvage surgery was administered in which the microanastomoses

  11. Red blood cell phase separation in symmetric and asymmetric microchannel networks: effect of capillary dilation and inflow velocity

    Science.gov (United States)

    Clavica, Francesco; Homsy, Alexandra; Jeandupeux, Laure; Obrist, Dominik

    2016-11-01

    The non-uniform partitioning or phase separation of red blood cells (RBCs) at a diverging bifurcation of a microvascular network is responsible for RBC heterogeneity within the network. The mechanisms controlling RBC heterogeneity are not yet fully understood and there is a need to improve the basic understanding of the phase separation phenomenon. In this context, in vitro experiments can fill the gap between existing in vivo and in silico models as they provide better controllability than in vivo experiments without mathematical idealizations or simplifications inherent to in silico models. In this study, we fabricated simple models of symmetric/asymmetric microvascular networks; we provided quantitative data on the RBC velocity, line density and flux in the daughter branches. In general our results confirmed the tendency of RBCs to enter the daughter branch with higher flow rate (Zweifach-Fung effect); in some cases even inversion of the Zweifach-Fung effect was observed. We showed for the first time a reduction of the Zweifach-Fung effect with increasing flow rate. Moreover capillary dilation was shown to cause an increase of RBC line density and RBC residence time within the dilated capillary underlining the possible role of pericytes in regulating the oxygen supply.

  12. Evaluation of multi-slice spiral CT perfusion on blood supply of rabbits model bearing VX2 hepatic carcinoma%多排螺旋CT灌注成像对兔VX2肝癌血供的评价

    Institute of Scientific and Technical Information of China (English)

    周悦; 高剑波; 杨学华; 张永高; 岳松伟; 曲艳红

    2011-01-01

    Aim:To assess the diagnostic value of Muhi-slice CT perfusion for blood supply evaluation of the rabbits VX2 hepatic tumors. Methods: VX2 hepatic carcinoma mass were implanted into the left lobe of liver of 30 rabbits via laparotomic route. Multi-slice CT enhancement and perfusion were performed in these rabbits at twenty-one day after implantation. The CT imaging features of the tumors were observed and the perfusion parameters were measured in the rim of the tumor, non-tumorous regions nearby the tumor and the normal liver tissues. Results: Twenty-five (83%) rabbits were sucessfully implanted with the tumor. The tumors which has smooth border were demostrated itself as the round-shaped tumors with hypodensity on plain CT scan,significantly tinge-enhancement on arterial phase, relatively hypodensity on portal phase and no enhanced in the zone of necrosis. Blood flow, blood volume, permeability surface, hepatic arterial fraction, hepatic arterial perfusion increased and mean transit time decreased in the rim of the tumor compared with those of the non-normorous regions nearby the tumor and the normal liver ( P < 0.05). Conclusion: Multi-slice CT perfusion could evaluate the blood supply station of hepatic tumors in vivo by perfusion parameters.%目的:探讨多排螺旋CT灌注成像对兔VX2肝癌血供的评价价值.方法:采用开腹瘤组织块直接包埋法将VX2肝癌移植瘤植入30只新西兰大白兔肝左叶,并于种植后第21天行多排螺旋CT增强及灌注扫描,观察其CT征象,并对比肿瘤边缘区、瘤旁肝组织以及对照肝组织的CT灌注参数(血流量、血容量、平均通过时间、表面通透性、肝动脉分数以及肝动脉灌注量).结果:25只(83%)大白兔种植成功.CT平扫肿瘤为类圆形低密度灶;增强动脉期病灶表现为边缘环状强化;门脉期呈相对低密度,中心见低密度坏死区,与周围组织界限较清.CT灌注成像结果:肿瘤边缘区、瘤旁肝组织及对照肝

  13. Secretory glands and microvascular systems imaged in aqueous solution by atmospheric scanning electron microscopy (ASEM).

    Science.gov (United States)

    Yamazawa, Toshiko; Nakamura, Naotoshi; Sato, Mari; Sato, Chikara

    2016-12-01

    Exocrine glands, e.g., salivary and pancreatic glands, play an important role in digestive enzyme secretion, while endocrine glands, e.g., pancreatic islets, secrete hormones that regulate blood glucose levels. The dysfunction of these secretory organs immediately leads to various diseases, such as diabetes or Sjögren's syndrome, by poorly understood mechanisms. Gland-related diseases have been studied by optical microscopy (OM), and at higher resolution by transmission electron microscopy (TEM) of Epon embedded samples, which necessitates hydrophobic sample pretreatment. Here, we report the direct observation of tissue in aqueous solution by atmospheric scanning electron microscopy (ASEM). Salivary glands, lacrimal glands, and pancreas were fixed, sectioned into slabs, stained with phosphotungstic acid (PTA), and inspected in radical scavenger d-glucose solution from below by an inverted scanning electron microscopy (SEM), guided by optical microscopy from above to target the tissue substructures. A 2- to 3-µm specimen thickness was visualized by the SEM. In secretory cells, cytoplasmic vesicles and other organelles were clearly imaged at high resolution, and the former could be classified according to the degree of PTA staining. In islets of Langerhans, the microvascular system used as an outlet by the secretory cells was also clearly observed. Microvascular system is also critically involved in the onset of diabetic complications and was clearly visible in subcutaneous tissue imaged by ASEM. The results suggest the use of in-solution ASEM for histology and to study vesicle secretion systems. Further, the high-throughput of ASEM makes it a potential tool for the diagnosis of exocrine and endocrine-related diseases.

  14. Preparation of a designed poly(trimethylene carbonate) microvascular network by stereolithography.

    Science.gov (United States)

    Schüller-Ravoo, Sigrid; Zant, Erwin; Feijen, Jan; Grijpma, Dirk W

    2014-12-01

    Designed flexible and elastic network structures are prepared by stereolithography using a photo-crosslinkable resin based on a poly(trimethylene carbonate) (PTMC) macromer with a molecular weight of 3150 g/mol. Physical properties and the compatibility with human umbilical vein endothelial cells (HUVECs) are evaluated. The hydrophobic networks are found to be flexible and elastic, with an E modulus of 7.9 ± 0.1 MPa, a tensile strength of 3.5 ± 0.1 MPa and an elongation at break of 76.7 ± 0.7%. HUVECs attach and proliferate well on the surfaces of the built structures. A three-dimensional microvascular network is designed to serve as a perfusable scaffold for tissue engineering. In the design, 5 generations of open channels each branch into 4 smaller channels yielding a microvascular region with a high density of capillaries. The overall cross-sectional area through which medium or blood can be perfused remains constant. These structures would ensure efficient nourishment of cells in a large volume of tissue. Built by stereolithography using the PTMC resin, the smallest channels of these structures have square cross-sectional areas, with inner widths of approximately 224 μm and wall thicknesses of approximately 152 μm. The channels are open, allowing water to perfuse the scaffold at 0.279 ± 0.006 mL/s at 80 mmHg and 0.335 ± 0.009 mL/s at 120 mmHg.

  15. Microvascular anatomy of spinal dural arteriovenous fistulas: arteriovenous connections and their relationships with the dura mater.

    Science.gov (United States)

    Takai, Keisuke; Komori, Takashi; Taniguchi, Makoto

    2015-10-01

    OBJECT The microvascular anatomy of spinal dural arteriovenous fistulas (AVFs), especially the relationships of the vessels with the dura mater, has yet to be angiographically demonstrated in detail and proven histologically. METHODS From January 2012 through April 2014, a total of 7 patients with spinal dural AVFs in the thoracic region underwent open microsurgical obliteration at Tokyo Metropolitan Neurological Hospital. The microvascular anatomy of spinal dural AVFs was comprehensively assessed by using advanced microangiography, including 3D computer graphics and intraoperative indocyanine green video angiography, and by histological findings. RESULTS The 2 microangiography techniques revealed the spatial course and in vivo blood flow of the meningeal vessels and their relationships with the dura mater in sufficient detail. The meningeal branch of the intercostal artery split into multiple meningeal vessels on the outer dural surface adjacent to the root sleeve. After crossing the dura mater to the inner dural surface, these vessels gathered and joined a single intradural draining vessel. On the inner dural surface, the single draining vessel was fed by the surrounding multiple meningeal vessels, which appeared to be caput medusae. Histological findings revealed that the structure of the meningeal branch of the intercostal artery corresponded to that of a normal artery. The structure of intradural draining vessels corresponded to that of a vein modified by retrograde arterial inflow. On the inner dural surface, more than 1 meningeal artery gathered and joined with the proximal radiculomedullary vein. CONCLUSIONS Spinal dural AVFs are located on the inner dural surface, where multiple direct AV connections between more than 1 meningeal feeding artery and a single proximal radiculomedullary vein occur at the site where the vein connects to the dura mater.

  16. Real-time 3D Fourier-domain optical coherence tomography guided microvascular anastomosis

    Science.gov (United States)

    Huang, Yong; Ibrahim, Zuhaib; Lee, W. P. A.; Brandacher, Gerald; Kang, Jin U.

    2013-03-01

    Vascular and microvascular anastomosis is considered to be the foundation of plastic and reconstructive surgery, hand surgery, transplant surgery, vascular surgery and cardiac surgery. In the last two decades innovative techniques, such as vascular coupling devices, thermo-reversible poloxamers and suture-less cuff have been introduced. Intra-operative surgical guidance using a surgical imaging modality that provides in-depth view and 3D imaging can improve outcome following both conventional and innovative anastomosis techniques. Optical coherence tomography (OCT) is a noninvasive high-resolution (micron level), high-speed, 3D imaging modality that has been adopted widely in biomedical and clinical applications. In this work we performed a proof-of-concept evaluation study of OCT as an assisted intraoperative and post-operative imaging modality for microvascular anastomosis of rodent femoral vessels. The OCT imaging modality provided lateral resolution of 12 μm and 3.0 μm axial resolution in air and 0.27 volume/s imaging speed, which could provide the surgeon with clearly visualized vessel lumen wall and suture needle position relative to the vessel during intraoperative imaging. Graphics processing unit (GPU) accelerated phase-resolved Doppler OCT (PRDOCT) imaging of the surgical site was performed as a post-operative evaluation of the anastomosed vessels and to visualize the blood flow and thrombus formation. This information could help surgeons improve surgical precision in this highly challenging anastomosis of rodent vessels with diameter less than 0.5 mm. Our imaging modality could not only detect accidental suture through the back wall of lumen but also promptly diagnose and predict thrombosis immediately after reperfusion. Hence, real-time OCT can assist in decision-making process intra-operatively and avoid post-operative complications.

  17. ID3 contributes to the acquisition of molecular stem cell-like signature in microvascular endothelial cells: its implication for understanding microvascular diseases.

    Science.gov (United States)

    Das, Jayanta K; Voelkel, Norbert F; Felty, Quentin

    2015-03-01

    While significant progress has been made to advance our knowledge of microvascular lesion formation, yet the investigation of how stem-like cells may contribute to the pathogenesis of microvascular diseases is still in its infancy. We assessed whether the inhibitor of DNA binding and differentiation 3 (ID3) contributes to the acquisition of a molecular stem cell-like signature in microvascular endothelial cells. The effects of stable ID3 overexpression and SU5416 treatment - a chemical inducer of microvascular lesions, had on the stemness signature were determined by flow cytometry, immunoblot, and immunohistochemistry. Continuous ID3 expression produced a molecular stemness signature consisting of CD133(+) VEGFR3(+) CD34(+) cells. Cells exposed to SU5416 showed positive protein expression of ID3, VEGFR3, CD34 and increased expression of pluripotent transcription factors Oct-4 and Sox-2. ID3 overexpressing cells supported the formation of a 3-D microvascular lesion co-cultured with smooth muscle cells. In addition, in vivo microvascular lesions from SuHx rodent model showed an increased expression of ID3, VEGFR3, and Pyk2 similar to SU5416 treated human endothelial cells. Further investigations into how normal and stem-like cells utilize ID3 may open up new avenues for a better understanding of the molecular mechanisms which are underlying the pathological development of microvascular diseases.

  18. Functional blood flow patterns of the endolymphatic sac in the rat

    DEFF Research Database (Denmark)

    Friis, Morten; Qvortrup, Klaus

    2008-01-01

    Conclusion. Visualization of the endolymphatic sac vascular network under video fluorescence microscopy showed a typical microvascular organization. The microvascular arrangement and the microcirculation may reflect a functional state of the endolymphatic sac. Damage or change of the blood...... circulation following endolymphatic sac surgery is discussed. Objectives. To visualize and study the dynamic microcirculation of the endolymphatic sac in live rats. Method. An experimental animal study using in vivo video fluorescence microscopy. Results. Visualization of the endolymphatic sac vascular...

  19. Studies of pathological dynamics after microvascular injury using nonlinear optical methods

    Science.gov (United States)

    Rosidi, Nathanael L.

    Microvascular lesions are a common feature in the aging brain and clinical evidence has correlated microvascular pathology with the development of neurodegenerative diseases such as Alzheimer's disease and dementia. Traditional animal models that replicate hemorrhagic and ischemic lesions in the brain typically affect large regions in the cortex and do not reproduce the small-scale lesions linked to neurodegeneration that likely stem from injuries to single microvessels. Due in part to this lack of small-scale injury animal models, there remains an incomplete understanding of the cellular and pathophysiological dynamics following small-scale vascular lesions, making progress on therapeutic strategies difficult. We used tightly focused femtosecond laser pulses to injure single penetrating arterioles (PA) (i.e., arterioles that plunge into the brain) in the cortex of live anesthetized rodents and used two-photon excited fluorescence (2PEF) imaging to quantify blood flow changes and to determine the time course of pathological consequences in the brain after injury. We find that after ischemic occlusion of a PA, nearby pial and penetrating arterioles do not actively compensate for the reduction of blood flow observed near the occluded blood vessel. We find that capillaries connected downstream to the clotted vessel dilate but other capillaries in the vicinity do not, suggesting that any compensatory signal that results in a physiological response travels vascularly. We ruptured individual PAs to induce microhemorrhages that resulted in extravasation of blood into the parenchyma. We find that tissue compression due to the hematoma does not collapse capillaries and cause acute ischemia. 2PEF imaging of mice expressing yellow fluorescent protein (YFP) in a subset of cortical neurons revealed no dendrite degeneration out to seven days after microhemorrhage. However, we did observe an inflammatory response by microglia/macrophages as quickly as 1.5-hrs after

  20. Assessing the effects of a short-term green tea intervention in skin microvascular function and oxygen tension in older and younger adults.

    Science.gov (United States)

    Wasilewski, Rebecca; Ubara, Emmanuel O; Klonizakis, Markos

    2016-09-01

    Green tea consumption has been associated with a reduction in cardiovascular disease risk factors. However, there is little evidence examining its potential differing effect between younger and older populations, whilst little is known on its effect on the circulatory system when oxygen demand is higher. Therefore the aim of this study was to evaluate the short-term effects of green tea consumption on microvascular functioning in both an older and younger population. Fifteen young [24 (4.0)] and fifteen older [61 (4.0)] participants, consumed two cups of green tea daily for 14days. We used Laser Doppler Flowmetry (LDF) to assess cutaneous microvascular function and Transcutaneous Oxygen monitoring (TcPO2) to assess skin oxygen tension. Systolic and diastolic blood pressure were also assessed on both visits. We observed significant improvements in axon-mediated microvascular vasodilation for the younger group [1.6 (0.59) vs 2.05 (0.72), p<0.05] and the older group [1.25 (0.58) vs 1.65 (0.5) p<0.05]. Improvements in skin oxygen tension were also noted for both groups in both noted TcPO2 measures (i.e. 1.25 (0.58) vs 1.65 (0.5) (p<0.05), for ΔTcPO2max for the older group, between visits) respectively. Improvements were also observed for systolic blood pressure in both the younger [120 (10) vs 112 (10), p<0.05] and older group [129 (12) v 124 (11), p<0.001]. In conclusion, we observed statistically-significant improvements in microvascular function and skin oxygen tension. Our results suggest that green tea may prove beneficial as a dietary element in lifestyle interventions aiming to lower cardiovascular disease risk, in both older and younger populations.

  1. Protective effects of quercetin on rat pial microvascular changes during transient bilateral common carotid artery occlusion and reperfusion.

    Directory of Open Access Journals (Sweden)

    Dominga eLapi

    2012-03-01

    Full Text Available The aim of this study was to assess the in vivo effects of quercetin on pial microvascular responses during transient bilateral common carotid artery occlusion (BCCAO and reperfusion. Rat pial microcirculation was visualized by fluorescence microscopy through a closed cranial window. Pial arterioles were classified in five orders of branchings. Capillaries were assigned order 0, the smallest arterioles order 1 and the largest ones order 5. In ischemic rats, 30 min BCCAO and 60 min reperfusion caused arteriolar diameter decrease (by 14.5 ± 3.3% of baseline in order 2, microvascular leakage (0.47 ± 0.04 NGL: Normalized Grey Levels, leukocyte adhesion in venules (9 ± 2/100 µm venular length, v.l./30s and reduction of capillary perfusion (by 40 ± 7% of baseline. Moreover, at the end of BCCAO and reperfusion there was a significant increase in reactive oxygen species formation (ROS when compared with baseline. Quercetin highest dose determined dilation in all arteriolar orders (by 40 ± 4 % of baseline in order 2 and prevented microvascular permeability (0.15 ± 0.02 NGL, leukocyte adhesion (3 ± 1/100 µm v.l./30s as well as ROS formation, while capillary perfusion was protected. Inhibition of endothelial Nitric Oxide Synthase (NOS prior to quercetin reduced arteriolar dilation (order 2 diameter increase by 10.3 ± 2.5% of baseline and caused permeability increase (0.29 ± 0.03 NGL; inhibition of neuronal NOS or inducible NOS did not affect quercetin-induced effects. Inhibition of guanylyl cyclase prior to quercetin reversed the quercetin’s effects on pial arteriolar diameter and leakage. In conclusion, quercetin was able to protect pial microcirculation from ischemia-reperfusion damage inducing arteriolar dilation likely by nitric oxide release. Moreover, quercetin scavenger activity blunted reactive oxygen species formation preserving the blood-brain barrier integrity.

  2. Brazil nuts intake improves lipid profile, oxidative stress and microvascular function in obese adolescents: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Koury Josely C

    2011-05-01

    Full Text Available Abstract Background Obesity is a chronic disease associated to an inflammatory process resulting in oxidative stress that leads to morpho-functional microvascular damage that could be improved by some dietary interventions. In this study, the intake of Brazil nuts (Bertholletia excelsa, composed of bioactive substances like selenium, α- e γ- tocopherol, folate and polyunsaturated fatty acids, have been investigated on antioxidant capacity, lipid and metabolic profiles and nutritive skin microcirculation in obese adolescents. Methods Obese female adolescents (n = 17, 15.4 ± 2.0 years and BMI of 35.6 ± 3.3 kg/m2, were randomized 1:1 in two groups with the diet supplemented either with Brazil nuts [BNG, n = 08, 15-25 g/day (equivalent to 3 to 5 units/day] or placebo [PG (lactose, n = 09, one capsule/day] and followed for 16 weeks. Anthropometry, metabolic-lipid profiles, oxidative stress and morphological (capillary diameters and functional [functional capillary density, red blood cell velocity (RBCV at baseline and peak (RBCVmax and time (TRBCVmax to reach it during post-occlusive reactive hyperemia, after 1 min arterial occlusion] microvascular variables were assessed by nailfold videocapillaroscopy at baseline (T0 and after intervention (T1. Results T0 characteristics were similar between groups. At T1, BNG (intra-group variation had increased selenium levels (p = 0.02, RBCV (p = 0.03 and RBCVmax (p = 0.03 and reduced total (TC (p = 0.02 and LDL-cholesterol (p = 0.02. Compared to PG, Brazil nuts intake reduced TC (p = 0.003, triglycerides (p = 0.05 and LDL-ox (p = 0.02 and increased RBCV (p = 0.03. Conclusion Brazil nuts intake improved the lipid profile and microvascular function in obese adolescents, possibly due to its high level of unsaturated fatty acids and bioactive substances. Trial Registration Clinical Trials.gov NCT00937599

  3. Wide-area mapping of resting state hemodynamic correlations at microvascular resolution with multi-contrast optical imaging (Conference Presentation)

    Science.gov (United States)

    Senarathna, Janaka; Hadjiabadi, Darian; Gil, Stacy; Thakor, Nitish V.; Pathak, Arvind P.

    2017-02-01

    Different brain regions exhibit complex information processing even at rest. Therefore, assessing temporal correlations between regions permits task-free visualization of their `resting state connectivity'. Although functional MRI (fMRI) is widely used for mapping resting state connectivity in the human brain, it is not well suited for `microvascular scale' imaging in rodents because of its limited spatial resolution. Moreover, co-registered cerebral blood flow (CBF) and total hemoglobin (HbT) data are often unavailable in conventional fMRI experiments. Therefore, we built a customized system that combines laser speckle contrast imaging (LSCI), intrinsic optical signal (IOS) imaging and fluorescence imaging (FI) to generate multi-contrast functional connectivity maps at a spatial resolution of 10 μm. This system comprised of three illumination sources: a 632 nm HeNe laser (for LSCI), a 570 nm ± 5 nm filtered white light source (for IOS), and a 473 nm blue laser (for FI), as well as a sensitive CCD camera operating at 10 frames per second for image acquisition. The acquired data enabled visualization of changes in resting state neurophysiology at microvascular spatial scales. Moreover, concurrent mapping of CBF and HbT-based temporal correlations enabled in vivo mapping of how resting brain regions were linked in terms of their hemodynamics. Additionally, we complemented this approach by exploiting the transit times of a fluorescent tracer (Dextran-FITC) to distinguish arterial from venous perfusion. Overall, we demonstrated the feasibility of wide area mapping of resting state connectivity at microvascular resolution and created a new toolbox for interrogating neurovascular function.

  4. Association of Maternal Antiangiogenic Profile at Birth With Early Postnatal Loss of Microvascular Density in Offspring of Hypertensive Pregnancies

    Science.gov (United States)

    Yu, Grace Z.; Aye, Christina Y.L.; Lewandowski, Adam J.; Davis, Esther F.; Khoo, Cheen P.; Newton, Laura; Yang, Cheng T.; Al Haj Zen, Ayman; Simpson, Lisa J.; O’Brien, Kathryn; Cook, David A.; Granne, Ingrid; Kyriakou, Theodosios; Channon, Keith M.; Watt, Suzanne M.

    2016-01-01

    Offspring of hypertensive pregnancies are more likely to have microvascular rarefaction and increased blood pressure in later life. We tested the hypothesis that maternal angiogenic profile during a hypertensive pregnancy is associated with fetal vasculogenic capacity and abnormal postnatal microvascular remodeling. Infants (n=255) born after either hypertensive or normotensive pregnancies were recruited for quantification of postnatal dermal microvascular structure at birth and 3 months of age. Vasculogenic cell potential was assessed in umbilical vein endothelial cells from 55 offspring based on in vitro microvessel tube formation and proliferation assays. Maternal angiogenic profile (soluble fms-like tyrosine kinase-1, soluble endoglin, vascular endothelial growth factor, and placental growth factor) was measured from postpartum plasma samples to characterize severity of pregnancy disorder. At birth, offspring born after hypertensive pregnancy had similar microvessel density to those born after a normotensive pregnancy, but during the first 3 postnatal months, they had an almost 2-fold greater reduction in total vessel density (−17.7±16.4% versus −9.9±18.7%; P=0.002). This postnatal loss varied according to the vasculogenic capacity of the endothelial cells of the infant at birth (r=0.49; P=0.02). The degree of reduction in both in vitro and postnatal in vivo vascular development was proportional to levels of antiangiogenic factors in the maternal circulation. In conclusion, our data indicate that offspring born to hypertensive pregnancies have reduced vasculogenic capacity at birth that predicts microvessel density loss over the first 3 postnatal months. Degree of postnatal microvessel reduction is proportional to levels of antiangiogenic factors in the maternal circulation at birth. PMID:27456522

  5. Relationship Between Different Subpopulations of Circulating CD4+ T-lymphocytes and Microvascular Structural Alterations in Humans.

    Science.gov (United States)

    De Ciuceis, Carolina; Rossini, Claudia; Airò, Paolo; Scarsi, Mirko; Tincani, Angela; Tiberio, Guido Alberto Massimo; Piantoni, Silvia; Porteri, Enzo; Solaini, Leonardo; Duse, Sarah; Semeraro, Francesco; Petroboni, Beatrice; Mori, Luigi; Castellano, Maurizio; Gavazzi, Alice; Agabiti Rosei, Claudia; Agabiti Rosei, Enrico; Rizzoni, Damiano

    2017-01-01

    Different components of the immune system, including innate and adaptive immunity (T-effector lymphocytes and T-regulatory lymphocytes-TREGs) may be involved in the development of hypertension. In addition, it was demonstrated in animal models that TREGs may prevent angiotensin II-induced hypertension and vascular injury/inflammation. However, no data are presently available in humans about possible relationships between T-lymphocyte subtypes and microvascular structural alterations. For this purpose, in the present study, we enrolled 24 normotensive subjects and 12 hypertensive patients undergoing an elective surgical intervention. No sign of local or systemic inflammation was present. All patients underwent a biopsy of subcutaneous fat during surgery. Subcutaneous small resistance arteries were dissected and mounted on a wire myograph and the media to lumen ratio (M/L) was calculated. In addition, retinal arteriolar structure was evaluated noninvasively by scanning laser Doppler flowmetry. Capillary density in the nailfold, dorsum of the finger, and forearm were evaluated by videomicroscopy. A peripheral blood sample was obtained before surgery for assessment of T-lymphocyte subpopulations by flow cytometry. Significant negative correlations were observed between indices of microvascular structure (M/L of subcutaneous small arteries and wall to lumen ratio of retinal arterioles) and circulating TREG lymphocytes. A direct correlation was observed between M/L of subcutaneous small arteries and circulating Th17 lymphocytes. In addition, total capillary density was correlated with a TREG effector memory subpopulation. Our data suggest that some lymphocyte subpopulations may be related to microvascular remodeling, confirming previous animal data, and opening therapeutic possibilities. © American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Vitamin D levels and microvascular complications in type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Sarita Bajaj

    2014-01-01

    Full Text Available Background: Vitamin D has important actions on glucose metabolism. These include improved insulin exocytosis, direct stimulation of insulin receptor, improved uptake of glucose by peripheral tissues, improving insulin resistance. It has got various pleiotropic effects like suppression of cell mediated immunity, regulation of cell proliferation, stimulation of neurotropic factors such as nerve growth factor, Glial cell line-derived neurotrophic factor, neurotropin, suppression of RAAS, reduction of albuminuria, immunomodulatory effects, and anti-inflammatory effects. Thus, vitamin D is implicated in many ways in the pathogenesis of retinopathy, neuropathy and nephropathy. Objectives: To study the correlation of vitamin D levels with microvascular complications in type 2 diabetes. Materials and Methods: Cross-sectional case-control study of 18 patients (18-70 years, who met the American Diabetes Association 2011 criteria for type 2 diabetes, was conducted. Age and sex matched healthy controls were taken. Subjects were evaluated for the presence of microvascular complications by clinical evaluation, urine examination, fundus examination, nerve conduction studies, and various biochemical tests. 25-OH cholecalciferol levels were done for each. Cut off level for vitamin D deficiency was 20 ng/ml. Results: Mean vitamin D was lower in type 2 diabetics than healthy subjects (19.046 vs. 27.186 ng/ml. Prevalence of vitamin D deficiency and insufficiency was found to significantly higher in diabetics when compared to healthy subjects (P = 0.0001. Vitamin D deficiency was found to be significantly associated with neuropathy (χ2 = 5.39, df = 1, P = 0.020, retinopathy, (χ2 = 6.6, df = 1, P = 0.010 and nephropathy (χ2 = 10. 52, df = 1, P = 0.001. Lower levels of vitamin D were found to be associated with increasing prevalence of combinations of microvascular complications namely neuropathy with retinopathy (P = 0.036, neuropathy with nephropathy (P = 0

  7. Acute Thermotherapy Prevents Impairments in Cutaneous Microvascular Function Induced by a High Fat Meal

    Science.gov (United States)

    Harvey, Jennifer C.; Roseguini, Bruno T.; Goerger, Benjamin M.; Fallon, Elizabeth A.

    2016-01-01

    We tested the hypothesis that a high fat meal (HFM) would impair cutaneous vasodilation, while thermotherapy (TT) would reverse the detrimental effects. Eight participants were instrumented with skin heaters and laser-Doppler (LD) probes and tested in three trials: control, HFM, and HFM + TT. Participants wore a water-perfused suit perfused with 33°C (control and HFM) or 50°C (HFM + TT) water. Participants consumed 1 g fat/kg body weight. Blood samples were taken at baseline and two hours post-HFM. Blood pressure was measured every 5–10 minutes. Microvascular function was assessed via skin local heating from 33°C to 39°C two hours after HFM. Cutaneous vascular conductance (CVC) was calculated and normalized to maximal vasodilation (%CVCmax). HFM had no effect on initial peak (48 ± 4 %CVCmax) compared to control (49 ± 4 %CVCmax) but attenuated the plateau (51 ± 4 %CVCmax) compared to control (63 ± 4 %CVCmax, P < 0.001). Initial peak was augmented in HFM + TT (66 ± 4 %CVCmax) compared to control and HFM (P < 0.05), while plateau (73 ± 3 % CVCmax) was augmented only compared to the HFM trial (P < 0.001). These data suggest that HFM negatively affects cutaneous vasodilation but can be minimized by TT. PMID:27595112

  8. Signal Intensity of Superb Microvascular Imaging Correlates with the Severity of Acute Cholecystitis

    Directory of Open Access Journals (Sweden)

    Minoru Tomizawa

    2016-08-01

    Full Text Available Evaluation of the severity of acute cholecystitis is critical for the management of this condition. Superb microvascular imaging (SMI enables the assessment of slow blood flow of small vessels without any contrast medium. An 84-year-old man visited our hospital with right upper abdominal pain. Computed tomography and abdominal ultrasonography showed a slight thickening of the gallbladder. White blood cell count and C-reactive protein levels were elevated. He was diagnosed with acute cholecystitis and treated conservatively with antibiotics. Two days later, his condition worsened and percutaneous transhepatic gallbladder drainage (PTGBD was performed. The patient recovered and was discharged, and his drainage was withdrawn 7 days later. On admission, color-coded SMI (cSMI showed pulsatory signals on the slightly thickened gallbladder wall. On the day of PTGBD, the intensity of the signal on cSMI had increased. Once the patient was cured, no further signal was observed on the gallbladder wall with either cSMI or mSMI. In conclusion, the strong pulsatory signal correlated with the severity of acute cholecystitis observed with cSMI and mSMI. Illustrating the signal intensity is useful for the evaluation of the severity of acute cholecystitis.

  9. Signal Intensity of Superb Microvascular Imaging Correlates with the Severity of Acute Cholecystitis

    Science.gov (United States)

    Tomizawa, Minoru; Shinozaki, Fuminobu; Motoyoshi, Yasufumi; Sugiyama, Takao; Yamamoto, Shigenori; Ishige, Naoki

    2016-01-01

    Evaluation of the severity of acute cholecystitis is critical for the management of this condition. Superb microvascular imaging (SMI) enables the assessment of slow blood flow of small vessels without any contrast medium. An 84-year-old man visited our hospital with right upper abdominal pain. Computed tomography and abdominal ultrasonography showed a slight thickening of the gallbladder. White blood cell count and C-reactive protein levels were elevated. He was diagnosed with acute cholecystitis and treated conservatively with antibiotics. Two days later, his condition worsened and percutaneous transhepatic gallbladder drainage (PTGBD) was performed. The patient recovered and was discharged, and his drainage was withdrawn 7 days later. On admission, color-coded SMI (cSMI) showed pulsatory signals on the slightly thickened gallbladder wall. On the day of PTGBD, the intensity of the signal on cSMI had increased. Once the patient was cured, no further signal was observed on the gallbladder wall with either cSMI or mSMI. In conclusion, the strong pulsatory signal correlated with the severity of acute cholecystitis observed with cSMI and mSMI. Illustrating the signal intensity is useful for the evaluation of the severity of acute cholecystitis. PMID:27721732

  10. Acute Thermotherapy Prevents Impairments in Cutaneous Microvascular Function Induced by a High Fat Meal

    Directory of Open Access Journals (Sweden)

    Jennifer C. Harvey

    2016-01-01

    Full Text Available We tested the hypothesis that a high fat meal (HFM would impair cutaneous vasodilation, while thermotherapy (TT would reverse the detrimental effects. Eight participants were instrumented with skin heaters and laser-Doppler (LD probes and tested in three trials: control, HFM, and HFM + TT. Participants wore a water-perfused suit perfused with 33°C (control and HFM or 50°C (HFM + TT water. Participants consumed 1 g fat/kg body weight. Blood samples were taken at baseline and two hours post-HFM. Blood pressure was measured every 5–10 minutes. Microvascular function was assessed via skin local heating from 33°C to 39°C two hours after HFM. Cutaneous vascular conductance (CVC was calculated and normalized to maximal vasodilation (%CVCmax. HFM had no effect on initial peak (48 ± 4 %CVCmax compared to control (49 ± 4 %CVCmax but attenuated the plateau (51 ± 4 %CVCmax compared to control (63 ± 4 %CVCmax, P < 0.001. Initial peak was augmented in HFM + TT (66 ± 4 %CVCmax compared to control and HFM (P < 0.05, while plateau (73 ± 3 % CVCmax was augmented only compared to the HFM trial (P < 0.001. These data suggest that HFM negatively affects cutaneous vasodilation but can be minimized by TT.

  11. Intercellular adhesion molecule-1 blockade attenuates inflammatory response and improves microvascular perfusion in rat pancreas grafts.

    Science.gov (United States)

    Preissler, Gerhard; Eichhorn, Martin; Waldner, Helmut; Winter, Hauke; Kleespies, Axel; Massberg, Steffen

    2012-10-01

    After pancreas transplantation (PTx), early capillary malperfusion and leukocyte recruitment indicate the manifestation of severe ischemia/reperfusion injury (IRI). Oscillatory blood-flow redistribution (intermittent capillary perfusion, IP), leading to an overall decrease in erythrocyte flux, precedes complete microvascular perfusion failure with persistent blood flow cessation. We addressed the role of intercellular adhesion molecule-1 (ICAM-1) for leukocyte-endothelial interactions (LEIs) after PTx and evaluated the contribution of IP and malperfusion. Pancreas transplantation was performed in rats after 18-hour preservation, receiving either isotype-matched IgG or monoclonal anti-ICAM-1 antibodies (10 mg/kg intravenously) once before reperfusion. Leukocyte-endothelial interaction, IP, erythrocyte flux, and functional capillary density, respectively, were examined in vivo during 2-hour reperfusion. Nontransplanted animals served as controls. Tissue samples were analyzed by histomorphometry. In grafts of IgG-treated animals, IP was encountered already at an early stage after reperfusion and steadily increased over 2 hours, whereas erythrocyte flux declined continuously. In contrast, inhibition of ICAM-1 significantly improved erythrocyte flux and delayed IP appearance by 2 hours. Further, anti-ICAM-1 significantly reduced LEI and leukocyte tissue infiltration when compared to IgG; edema development was less pronounced in response to anti-ICAM-1 monoclonal antibody. Intercellular adhesion molecule-1 blockade significantly attenuates IRI via immediate reduction of LEI and concomitant improvement of capillary perfusion patterns, emphasizing its central role during IRI in PTx.

  12. Eccentric exercise slows in vivo microvascular reactivity during brief contractions in human skeletal muscle.

    Science.gov (United States)

    Larsen, Ryan G; Hirata, Rogerio P; Madzak, Adnan; Frøkjær, Jens B; Graven-Nielsen, Thomas

    2015-12-01

    Unaccustomed exercise involving eccentric contractions results in muscle soreness and an overall decline in muscle function, however, little is known about the effects of eccentric exercise on microvascular reactivity in human skeletal muscle. Fourteen healthy men and women performed eccentric contractions of the dorsiflexor muscles in one leg, while the contralateral leg served as a control. At baseline, and 24 and 48 h after eccentric exercise, the following were acquired bilaterally in the tibialis anterior muscle: 1) transverse relaxation time (T2)-weighted magnetic resonance images to determine muscle cross-sectional area (mCSA) and T2; 2) blood oxygen level-dependent (BOLD) images during and following brief, maximal voluntary contractions (MVC) to monitor the hyperemic responses with participants positioned supine in a 3T magnet; 3) muscle strength; and 4) pain pressure threshold. Compared with the control leg, eccentric exercise resulted in soreness, decline in strength (∼20%), increased mCSA (∼7%), and prolonged T2 (∼7%) at 24 and 48 h (P eccentric exercise, such that time-to-peak (∼35%, P eccentric exercise may impede rapid adjustments in muscle blood flow at exercise onset and during activities involving brief bursts of muscle activation, which may impair O2 delivery and contribute to reduced muscle function after eccentric exercise. Copyright © 2015 the American Physiological Society.

  13. Risk factors for progression of microvascular complications in the Stockholm Diabetes Intervention Study (SDIS).

    Science.gov (United States)

    Reichard, P

    1992-05-01

    Ninety-six patients with insulin-dependent diabetes mellitus (IDDM), non-proliferative retinopathy, normal s-creatinine and previously high blood glucose levels were followed for 5 years. In multivariate analyses the mean HbA1c level (14 values during 6-60 months) was significantly correlated with albumin excretion level (P less than 0.01), retinopathy (P less than 0.001), motoric and sensoric nerve conduction velocities (P less than 0.01), thermal threshold on the foot (P less than 0.01), the respiratory sinus arrhythmia (P less than 0.01), the valsalva ratio (P less than 0.05) and the orthostatic blood pressure reaction (P = 0.05) after 5 years. Neuropathy was related to both the HbA1c value at baseline (P less than 0.05) and the mean HbA1c value during the study (P less than 0.001). Smoking habits were correlated with the total number of complications deteriorating (P less than 0.05), as was HbA1c during the study (P less than 0.001). Patients with an initial HbA1c of 9% or more could reduce the risks for deterioration of microvascular complications to 10-15% by reducing their HbA1c below this level.

  14. Continuous Dynamic Registration of Microvascularization of Liver Tumors with Contrast-Enhanced Ultrasound

    Directory of Open Access Journals (Sweden)

    Lukas Philipp Beyer

    2014-01-01

    Full Text Available Aim. To evaluate the diagnostic value of quantification of liver tumor microvascularization using contrast-enhanced ultrasound (CEUS measured continuously from the arterial phase to the late phase (3 minutes. Material and Methods. We present a retrospective analysis of 20 patients with malignant (n=13 or benign (n=7 liver tumors. The tumors had histopathologically been proven or clearly identified using contrast-enhanced reference imaging with either 1.5 T MRI (liver specific contrast medium or triphase CT and follow-up. CEUS was performed using a multifrequency transducer (1–5 MHz and a bolus injection of 2.4 mL sulphur hexafluoride microbubbles. A retrospective perfusion analysis was performed to determine TTP (time-to-peak, RBV (regional blood volume, RBF (regional blood flow, and Peak. Results. Statistics revealed a significant difference (P<0.05 between benign and malignant tumors in the RBV, RBF, and Peak but not in TTP (P=0.07. Receiver operating curves (ROC were generated for RBV, RBF, Peak, and TTP with estimated ROC areas of 0.97, 0.96, 0.98, and 0.76, respectively. Conclusion. RBV, RBF, and Peak continuously measured over a determined time period of 3 minutes could be of valuable support in differentiating malignant from benign liver tumors.

  15. Alternative venous outflow vessels in microvascular breast reconstruction.

    Science.gov (United States)

    Mehrara, Babak J; Santoro, Timothy; Smith, Andrew; Arcilla, Eric A; Watson, James P; Shaw, William W; Da Lio, Andrew L

    2003-08-01

    The lack of adequate recipient vessels often complicates microvascular breast reconstruction in patients who have previously undergone mastectomy and irradiation. In addition, significant size mismatch, particularly in the outflow veins, is an important contributor to vessel thrombosis and flap failure. The purpose of this study was to review the authors' experience with alternative venous outflow vessels for microvascular breast reconstruction. In a retrospective analysis of 1278 microvascular breast reconstructions performed over a 10-year period, the authors identified all patients in whom the external jugular or cephalic veins were used as the outflow vessels. Patient demographics, flap choice, the reasons for the use of alternative venous drainage vessels, and the incidence of microsurgical complications were analyzed. The external jugular was used in 23 flaps performed in procedures with 22 patients. The superior gluteal and transverse rectus abdominis musculocutaneous (TRAM) flaps were used in the majority of the cases in which the external jugular vein was used (72 percent gluteal, 20 percent TRAM flap). The need for alternative venous outflow vessels was usually due to a significant vessel size mismatch between the superior gluteal and internal mammary veins (74 percent). For three of the external jugular vein flaps (13 percent), the vein was used for salvage after the primary draining vein thrombosed, and two of three flaps in these cases were eventually salvaged. In three patients, the external jugular vein thrombosed, resulting in two flap losses, while the third was salvaged using the cephalic vein. A total of two flaps were lost in the external jugular vein group. The cephalic vein was used in 11 flaps (TRAM, 64.3 percent; superior gluteal, 35.7 percent) performed in 11 patients. In five patients (54.5 percent), the cephalic vein was used to salvage a flap after the primary draining vein thrombosed; the procedure was successful in four cases. In three

  16. On-line dynamic measurement of blood viscosity, hematocrit and change of blood volume

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To develop an on-line system for the measurement of blood viscosity and hematocrit. The dynamic changes of the macrovascular blood volumes,microvascular blood volumes and the total blood volume were observed by means of calculating from the testing result. Methods: Applying traditional viscosity measurement principle and specific wavelength optic density measurement method, an on-line system for the measurement of blood viscosity and hematocrit was developed, and the A/D multifunctionai board and the testing circuit were designed by ourselves. The system was validated by experiments both in vitro and in vivo. Therapeutic effects of hypertonic saline dextran solution (HSD) and Lactatic Ringer's solution at the early stage after burn-blast combined injury were compared by this method. Results: The results showed that the system has attained the goal of the design. The changes of the blood viscosity and hematocrit could be detected effectively and continuously. The changes of macrovascular, microvascular and total blood volume could be calculated approximately. Conclusions: The system and the method can continuously on-line test the blood viscosity and hematocrit, and reveal the change and distribution of blood volumes more accurately and dearly in the therapy process by estimating changes of the macrovascular, microvascular and total blood volumes, respectively. It has confirmed that HSD treatment could increase blood pressure and attenuate tissue edema by significantly increasing total blood volume,improving macrocirculatory and microcirculatory blood volumes. This study suggested that it could be desirable to develop an experiment technique based on the method mentioned above.

  17. The acute effects of exercise on the microvascular volume of Achilles tendons in healthy young subjects

    DEFF Research Database (Denmark)

    Pingel, Jessica; Harrison, Adrian; Suetta, Charlotte

    2013-01-01

    Real-time harmonic contrast-enhanced ultrasound (CEU) is used in several diseases to visualize the microvascularization in various tissues, due to its high sensitivity.......Real-time harmonic contrast-enhanced ultrasound (CEU) is used in several diseases to visualize the microvascularization in various tissues, due to its high sensitivity....

  18. Tumor necrosis factor-alpha increases myocardial microvascular transport in vivo

    DEFF Research Database (Denmark)

    Hansen, P R; Svendsen, Jesper Hastrup; Høyer, S

    1994-01-01

    ng/kg for 60 min) on myocardial microvascular transport of a small hydrophilic indicator was examined by the single-injection, residue-detection method. Intracoronary infusion of rTNF-alpha increased myocardial microvascular transport after 120 min. This increase was preceded by a sustained decline...

  19. Microvascular endothelial cell heterogeneity : general concepts and pharmacological consequences for anti-angiogenic therapy of cancer

    NARCIS (Netherlands)

    Langenkamp, Elise; Molema, Grietje

    2009-01-01

    Microvascular endothelial cells display a large degree of heterogeneity in function depending on their location in the vascular tree. The existence of organ-specific, microvascular-bed-specific, and even intravascular variations in endothelial cell gene expression emphasizes their high cell-to-cell

  20. Pathophysiology of hypertension: interactions between macro and microvascular alterations through endothelial dysfunction.

    Science.gov (United States)

    Yannoutsos, Alexandra; Levy, Bernard I; Safar, Michel E; Slama, Gerard; Blacher, Jacques

    2014-02-01

    Hypertension is a multifactorial systemic chronic disorder through functional and structural macrovascular and microvascular alterations. Macrovascular alterations are featured by arterial stiffening, disturbed wave reflection and altered central to peripheral pulse pressure amplification. Microvascular alterations, including altered wall-to-lumen ratio of larger arterioles, vasomotor tone abnormalities and network rarefaction, lead to disturbed tissue perfusion and susceptibility to ischemia. Central arterial stiffness and microvascular alterations are common denominators of organ damages. Vascular alterations are intercorrelated, amplifying the haemodynamic load and causing further damage in the arterial network. A plausible precursor role of vascular alterations in incident hypertension provides new insights for preventive and therapeutic strategies targeting macro and microvasculature. Cumulative metabolic burden and oxidative stress lead to chronic endothelial injury, promoting structural and functional vascular alterations, especially in the microvascular network. Pathophysiology of hypertension may then be revisited, based on both macrovascular and microvascular alterations, with a precursor role of endothelial dysfunction for the latter.

  1. Skin injury after embolization of ITA participating in blood supply of liver cancer%胸廓内动脉参与肝癌供血介入栓塞后皮肤损伤的发生及预防

    Institute of Scientific and Technical Information of China (English)

    宋鹏; 吴宁; 林福煌; 李斯锐; 陈峰

    2015-01-01

    目的:探讨胸廓内动脉(ITA)参与肝癌供血行介入栓塞治疗后皮肤损伤的发生特点及预防措施。方法对26例经血管造影确认有ITA参与肝癌供血者行ITA栓塞治疗。26例患者既往行TACE治疗2~6次,5例有肝切除病史。其中16例用碘油-抗癌药物乳剂栓塞,10例用碘化油及明胶海绵颗粒进行栓塞。8例用微导管行超选择性肿瘤供血动脉栓塞。术后观察并随访患者前胸壁及肝区皮肤变化。结果26例患者ITA参与肝癌供血者,右侧ITA 24例,左侧ITA 3例。19例介入治疗后出现不同程度前胸壁及肝区皮肤灼热感或针刺样疼痛。5例出现明显皮肤损伤,其中3例损伤皮肤出现破溃,1例继发感染。5例患者均应用碘油-抗癌药物乳剂行非选择性ITA栓塞。随诊1~4个月后5例均结痂愈合。结论皮肤损伤是经导管介入栓塞ITA的常见并发症,应用碘油-抗癌药物乳剂非选择性栓塞ITA是造成皮肤损伤的主要原因。%Objective To explore the characteristics and the preventive measures of skin injury after interventional embolization of internal thoracic artery (ITA) participating in the blood supply of liver cancer. Methods ITA embolization was performed in 26 hepatic carcinoma patients confirmed to be the tumor blood supply arteries by angiography. All of the 26 patients had received TACE treatment for 2 to 6 times, and 5 of them had received liver resection. A total of 16 patients received ITA embolization by lipiodol antineoplastic emulsion, but lipiodol and Gelfoam were used in the other 10 patients. Eight cases received super selective embolization with micro-catheter. Observe and follow-up the change of the anterior chest wall skin.Results Twenty-four of the 26 patients received RITA embolization, 3 received LITA embolization, and 1 patient received both RITA and LITA embolization. After interventional therapy, 19 patients experienced different degree of burning sense

  2. Modelo de suprimento sanguíneo do intestino delgado e grosso da preguiça de coleira (Bradypus torquatus Blood supply model of the small and large intestine of the maned three-toed sloth (Bradypus torquatus

    Directory of Open Access Journals (Sweden)

    Jussara Rocha Ferreira

    2013-06-01

    Full Text Available O Bradypus torquatus, conhecido como preguiça de coleira, está classificado na lista vermelha da IUCN como vulnerável. Este animal é um folívoro estrito que se alimenta de um pequeno número de plantas. O suprimento sanguíneo do intestino delgado e grosso de oito Bradypus torquatus, pertencentes ao acervo da Anatomia dos Animais Domésticos e Sivestres da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, foi estudado. O método incluiu preparação de relatório macroscópico, perfusão do sistema arterial com água (40°C, injeção de látex corado (Neoprene® 650, Sulvinil® 2350-0003, fixação com formaldeído (10%, conservação em solução modificada de Laskowiski e dissecação por mesoscopia de luz (Lupa LTS® 3700. A irrigação dos intestinos delgado e grosso dependeu da aorta abdominal, cujo ramo visceral ventral identificado como artéria mesentérica comum distribuiu-se no mesentério e mesocólon. Uma sequência de 9 a 25 ramos colaterais primários craniais destinaram-se ao duodeno, jejuno, íleo e parte da bolsa cecal. Outra sequência de 4 a 11 ramos caudais destinaram-se à bolsa cecal e cólons. No animal adulto, o modelo de vascularização do intestino diferiu dos outros vertebrados recentes em razão de não ocorrer coalescência peritoneal ao longo do intestino delgado e grosso.The Bradypus torquatus also known as maned three-toed sloth is listed as vulnerable in the IUCN red list. This species is strict folivorous that feeds on a relatively small number of food plants. The blood supply in the small and large intestines of eight Bradypus torquatus was studied. These animals are from the Anatomia dos Animais Domésticos e Silvestres collection of the Universidade de São Paulo . The method included preparation of the macroscopic collection report, perfusion of the arterial network with water (40°C, injection of colored latex (Neoprene 650®, 2350-0003 Suvinil® dye, fixation in

  3. Surveys of brain blood-supply status in acute and chronic schizophrenia patients%急慢性精神分裂症患者脑部供血状况临床研究

    Institute of Scientific and Technical Information of China (English)

    杨秀珍; 龚毅; 王跃升

    2015-01-01

    目的:探讨急慢性精神分裂症患者脑部供血状况的变化。方法采用超声多普勒对急、慢性精神分裂症患者(急性组和慢性组各35例)和正常人(对照组20名)的脑部供血状况进行检测分析,比较不同位置的血管脉动指数及血管阻力指数。结果慢性组在大脑前动脉、大脑中动脉、大脑后动脉、双侧椎动脉、小脑后下动脉及基底动脉血流参数显著高于急性组及对照组(P<0.05或0.01),右侧大脑半球更加明显(P<0.01)。急性组大脑中动脉、大脑后动脉右侧血管脉动指数均显著高于对照组(P<0.05或0.01)。结论慢性精神分裂症患者脑血流表现为高灌注状态,血管阻力偏高,以右侧大脑半球更加明显。%Objective To explore the changes of brain blood‐supply status in acute and chronic schizophre‐nia patients .Methods Detections and analyses were carried out using Doppler ultrasonography in acute and chronic schizophrenics (acute and chronic group of 35 ones each) and health adults (control group ,n=20) ,pulsatility indexes (PI) and resistant indexes (RI) of different positions compared .Results Blood flow parameters of anterior cerebral artery ,middle cerebral artery ,posterior cerebral artery ,bilateral ver‐tebral artery ,posterior inferior cerebellar artery and basilar artery were significantly higher in chronic than in acute and control group (P< 0 .05 or 0 .01) ,especially in right cerebral hemisphere (P< 0 .01) .Pulsa‐tility indexes of right middle and posterior cerebral artery were significantly higher in acute than in control group (P< 0 .05 or 0 .01) .Conclusion Cerebral blood flow of chronic schizophrenic manifests hypertrans‐fusion state and vascular resistance is higher ,especially in right cerebral hemisphere .

  4. Measurement of pulmonary flow reserve and pulmonary index of microcirculatory resistance for detection of pulmonary microvascular obstruction.

    Directory of Open Access Journals (Sweden)

    Rahn Ilsar

    Full Text Available BACKGROUND: The pulmonary microcirculation is the chief regulatory site for resistance in the pulmonary circuit. Despite pulmonary microvascular dysfunction being implicated in the pathogenesis of several pulmonary vascular conditions, there are currently no techniques for the specific assessment of pulmonary microvascular integrity in humans. Peak hyperemic flow assessment using thermodilution-derived mean transit-time (T(mn facilitate accurate coronary microcirculatory evaluation, but remain unvalidated in the lung circulation. Using a high primate model, we aimed to explore the use of T(mn as a surrogate of pulmonary blood flow for the purpose of measuring the novel indices Pulmonary Flow Reserve [PFR = (maximum hyperemic/(basal flow] and Pulmonary Index of Microcirculatory Resistance [PIMR = (maximum hyperemic distal pulmonary artery pressurex(maximum hyperemic T(mn]. Ultimately, we aimed to investigate the effect of progressive pulmonary microvascular obstruction on PFR and PIMR. METHODS AND RESULTS: Temperature- and pressure-sensor guidewires (TPSG were placed in segmental pulmonary arteries (SPA of 13 baboons and intravascular temperature measured. T(mn and hemodynamics were recorded at rest and following intra-SPA administration of the vasodilator agents adenosine (10-400 microg/kg/min and papaverine (3-24 mg. Temperature did not vary with intra-SPA sensor position (0.010+/-0.009 v 0.010+/-0.009 degrees C; distal v proximal; p = 0.1, supporting T(mn use in lung for the purpose of hemodynamic indices derivation. Adenosine (to 200 microg/kg/min & papaverine (to 24 mg induced dose-dependent flow augmentations (40+/-7% & 35+/-13% T(mn reductions v baseline, respectively; p<0.0001. PFR and PIMR were then calculated before and after progressive administration of ceramic microspheres into the SPA. Cumulative microsphere doses progressively reduced PFR (1.41+/-0.06, 1.26+/-0.19, 1.17+/-0.07 & 1.01+/-0.03; for 0, 10(4, 10(5 & 10(6 microspheres; p

  5. Microvascular responsiveness in obesity: implications for therapeutic intervention.

    Science.gov (United States)

    Bagi, Zsolt; Feher, Attila; Cassuto, James

    2012-02-01

    Obesity has detrimental effects on the microcirculation. Functional changes in microvascular responsiveness may increase the risk of developing cardiovascular complications in obese patients. Emerging evidence indicates that selective therapeutic targeting of the microvessels may prevent life-threatening obesity-related vascular complications, such as ischaemic heart disease, heart failure and hypertension. It is also plausible that alterations in adipose tissue microcirculation contribute to the development of obesity. Therefore, targeting adipose tissue arterioles could represent a novel approach to reducing obesity. This review aims to examine recent studies that have been focused on vasomotor dysfunction of resistance arteries in obese humans and animal models of obesity. Particularly, findings in coronary resistance arteries are contrasted to those obtained in other vascular beds. We provide examples of therapeutic attempts, such as use of statins, ACE inhibitors and insulin sensitizers to prevent obesity-related microvascular complications. We further identify some of the important challenges and opportunities going forward. 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.

  6. Angina pectoris in women: focus on microvascular disease.

    Science.gov (United States)

    Zuchi, Cinzia; Tritto, Isabella; Ambrosio, Giuseppe

    2013-02-20

    Ischemic heart disease (IHD) is the leading cause of death among women in Western countries, and it is associated with higher morbidity and mortality than in men. Nevertheless, IHD in women remains underdiagnosed and undertreated, and the misperception that females are "protected" against cardiovascular disease leads to underestimation of their cardiovascular risk; instead, women with chest pain have a high risk of cardiovascular events. Women suffering from angina pectoris tend to have different characteristics compared to men, with a high prevalence of non-significant coronary artery disease. Angina in women is more commonly microvascular in origin than in men, and therefore standard diagnostic algorithms may be suboptimal for women. This different pathophysiology impacts clinical management of IHD in women. While response to medical therapy may differ in women, they are scarcely represented in clinical trials. Therefore, solid data in terms of gender efficacy of antianginal drugs are lacking, and particularly when angina is microvascular in origin women often continue to be symptomatic despite maximal therapy with classical antianginal drugs. Recently, new molecules have shown promising results in women. In conclusion, women with angina are a group of patients in whom it seems appropriate to concentrate efforts aimed at reducing morbidity and improving quality of life.

  7. Quercetin protects human brain microvascular endothelial cells from fibrillar β-amyloid1–40-induced toxicity

    Directory of Open Access Journals (Sweden)

    Yongjie Li

    2015-01-01

    Full Text Available Amyloid beta-peptides (Aβ are known to undergo active transport across the blood-brain barrier, and cerebral amyloid angiopathy has been shown to be a prominent feature in the majority of Alzheimer׳s disease. Quercetin is a natural flavonoid molecule and has been demonstrated to have potent neuroprotective effects, but its protective effect on endothelial cells under Aβ-damaged condition is unclear. In the present study, the protective effects of quercetin on brain microvascular endothelial cells injured by fibrillar Aβ1–40 (fAβ1–40 were observed. The results show that fAβ1–40-induced cytotoxicity in human brain microvascular endothelial cells (hBMECs can be relieved by quercetin treatment. Quercetin increases cell viability, reduces the release of lactate dehydrogenase, and relieves nuclear condensation. Quercetin also alleviates intracellular reactive oxygen species generation and increases superoxide dismutase activity. Moreover, it strengthens the barrier integrity through the preservation of the transendothelial electrical resistance value, the relief of aggravated permeability, and the increase of characteristic enzyme levels after being exposed to fAβ1–40. In conclusion, quercetin protects hBMECs from fAβ1–40-induced toxicity.

  8. The Balance Between Metalloproteinases and TIMPs: Critical Regulator of Microvascular Endothelial Cell Function in Health and Disease.

    Science.gov (United States)

    Masciantonio, Marcello G; Lee, Christopher K S; Arpino, Valerie; Mehta, Sanjay; Gill, Sean E

    2017-01-01

    Endothelial cells (EC), especially the microvascular EC (MVEC), have critical functions in health and disease. For example, healthy MVEC provide a barrier between the fluid and protein found within the blood, and the surrounding tissue. Following tissue injury or infection, the microvascular barrier is often disrupted due to activation and dysfunction of the MVEC. Multiple mechanisms promote MVEC activation and dysfunction, including stimulation by cytokines, mechanical interaction with activated leukocytes, and exposure to harmful leukocyte-derived molecules, which collectively result in a loss of MVEC barrier function. However, MVEC activation is also critical to facilitate recruitment of inflammatory cells, such as neutrophils (PMNs) and monocytes, into the injured or infected tissue. Metalloproteinases, including the matrix metalloproteinases (MMPs) and the closely related, a disintegrin and metalloproteinases (ADAMs), have been implicated in regulating both MVEC barrier function, through cleavage of adherens and tight junctions proteins between adjacent MVEC and through degradation of the extracellular matrix, as well as PMN-MVEC interaction, through shedding of cell surface PMN receptors. Moreover, the tissue inhibitors of metalloproteinases (TIMPs), which collectively inhibit most MMPs and ADAMs, are critical regulators of MVEC activation and dysfunction through their ability to inhibit metalloproteinases and thereby promote MVEC stability. However, TIMPs have been also found to modulate MVEC function through metalloproteinase-independent mechanisms, such as regulation of vascular endothelial growth factor signaling. This chapter is focused on examining the role of the metalloproteinases and TIMPs in regulation of MVEC function in both health and disease. © 2017 Elsevier Inc. All rights reserved.

  9. On-line blood viscosity monitoring in vivo with a central venous catheter, using electrical impedance technique

    NARCIS (Netherlands)

    Pop, G.A.M.; Bisschops, L.L.A.; Iliev, B.; Struijk, P.C.; Hoeven, J.G. van der; Hoedemaekers, C.W.E.

    2013-01-01

    Blood viscosity is an important determinant of microvascular hemodynamics and also reflects systemic inflammation. Viscosity of blood strongly depends on the shear rate and can be characterized by a two parameter power-law model. Other major determinants of blood viscosity are hematocrit, level of i

  10. Associations of Macro- and Microvascular Endothelial Dysfunction With Subclinical Ventricular Dysfunction in End-Stage Renal Disease.

    Science.gov (United States)

    Dubin, Ruth F; Guajardo, Isabella; Ayer, Amrita; Mills, Claire; Donovan, Catherine; Beussink, Lauren; Scherzer, Rebecca; Ganz, Peter; Shah, Sanjiv J

    2016-10-01

    Patients with end-stage renal disease (ESRD) suffer high rates of heart failure and cardiovascular mortality, and we lack a thorough understanding of what, if any, modifiable factors contribute to cardiac dysfunction in these high-risk patients. To evaluate endothelial function as a potentially modifiable cause of cardiac dysfunction in ESRD, we investigated cross-sectional associations of macro- and microvascular dysfunction with left and right ventricular dysfunction in a well-controlled ESRD cohort. We performed comprehensive echocardiography, including tissue Doppler imaging and speckle-tracking echocardiography of the left and right ventricle, in 149 ESRD patients enrolled in an ongoing prospective, observational study. Of these participants, 123 also underwent endothelium-dependent flow-mediated dilation of the brachial artery (macrovascular function). Microvascular function was measured as the velocity time integral of hyperemic blood flow after cuff deflation. Impaired flow-mediated dilation was associated with higher left ventricular mass, independently of age and blood pressure: per 2-fold lower flow-mediated dilation, left ventricular mass was 4.1% higher (95% confidence interval, 0.49-7.7; P=0.03). After adjustment for demographics, blood pressure, comorbidities, and medications, a 2-fold lower velocity time integral was associated with 9.5% higher E/e' ratio (95% confidence interval, 1.0-16; P=0.03) and 6.7% lower absolute right ventricular longitudinal strain (95% confidence interval, 2.0-12; P=0.003). Endothelial dysfunction is a major correlate of cardiac dysfunction in ESRD, particularly diastolic and right ventricular dysfunction, in patients whose volume status is well controlled. Future investigations are needed to determine whether therapies targeting the vascular endothelium could improve cardiac outcomes in ESRD.

  11. Leishmaniosis--a report about the microvascular and cellular architecture of the infected spleen in Canis familiaris.

    Science.gov (United States)

    Alexandre-Pires, G; Pais, D; Correia, M; Pina, J A Esperança

    2006-04-01

    Leishmaniosis is an anthropozoonosis caused by an intracellular protozoan parasite that causes a wide spectrum of diseases in humans and dogs worldwide. In the Mediterranean basin, Portugal, Central and South America, and in the Middle East, visceral leishmaniosis is caused by Leishmania infantum. In these areas, dogs are believed to be the natural reservoirs of this parasite. In the case of visceral leishmaniosis, the spleen is one of the several hematopoietic and immunocompetent organs involved. Since this viscera is a blood filter, the authors investigated the expression of the morphological and microvascular environment and modifications of the spleen cell population related to immunological responses to this parasitic condition. The tools used to perform this study were scanning electronic microscopy of intact tissue and corrosion casts, transmission electronic microscopy, histology and immunohistochemistry. The results reveal three important modifications concerning the spleen's microvascular architecture when compared with its normal pattern, independently of the serological titer obtained with indirect immunofluorescence. (1) A marked scarcity of the sinusoidal system sheet that surrounds the central artery/arteriole of the white pulp; (2) A huge development of pulp venules and veins; (3) The presence of a surprising development of reticular fibers. The authors postulate that independent of the virulence of the parasite involved and the type of immunity prevalent in a particular host, the spleen develops blood dynamic conditions that permit reduction in the speed of blood flow so that cells involved in immunological processes can proliferate and differentiate, and also contributes to trapping lymphocytes within the area through the differentiation of characteristics that resemble those of HEV endothelial cells.

  12. Health supply chain management.

    Science.gov (United States)

    Zimmerman, Rolf; Gallagher, Pat

    2010-01-01

    This chapter gives an educational overview of: * The actual application of supply chain practice and disciplines required for service delivery improvement within the current health environment. * A rationale for the application of Supply Chain Management (SCM) approaches to the Health sector. * The tools and methods available for supply chain analysis and benchmarking. * Key supply chain success factors.

  13. Effect of osmolality on erythrocyte rheology and perfusion of an artificial microvascular network.

    Science.gov (United States)

    Reinhart, Walter H; Piety, Nathaniel Z; Goede, Jeroen S; Shevkoplyas, Sergey S

    2015-03-01

    Plasma sodium concentration is normally held within a narrow range. It may however vary greatly under pathophysiological conditions. Changes in osmolality lead to either swelling or shrinkage of red blood cells (RBCs). Here we investigated the influence of suspension osmolality on biophysical properties of RBCs and their ability to perfuse an artificial microvascular network (AMVN). Blood was drawn from healthy volunteers. RBC deformability was measured by osmotic gradient ektacytometry over a continuous range of osmolalities. Packed RBCs were suspended in NaCl solutions (0.45, 0.6, 0.9, 1.2, and 1.5 g/dL), resulting in supernatant osmolalities of 179 ± 4, 213 ± 1, 283 ± 2, 354 ± 3, and 423 ± 5 mOsm/kg H2O. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) were determined using centrifuged microhematocrit. RBC suspensions at constant cell numbers were used to measure viscosity at shear rates ranging from 0.11 to 69.5s(-1) and the perfusion rate of the AMVN. MCV was inversely and MCHC directly proportional to osmolality. RBC deformability was maximized at isosmotic conditions (290 mOsm/kg H2O) and markedly decreased by either hypo- or hyperosmolality. The optimum osmolality for RBC suspension viscosity was shifted toward hyperosmolality, while lower osmolalities increased suspension viscosity exponentially. However, the AMVN perfusion rate was maximized at 290 mOsm/kg H2O and changed by less than 10% over a wide range of osmolalities. These findings contribute to the basic understanding of blood flow in health and disease and may have significant implications for the management of osmotic homeostasis in clinical practice.

  14. Changes in microvascular permeability of the middle ear mucosa following the occulsion of the eustachian tube of rabbits. The functional investigation using radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Yasutaka

    1988-12-01

    Serial changes in submucosal microvascular permeability of the middle ear and the response to histamine after occlusion of the eustachian tube were functionally investigated using radioisotope in rabbits with experimentally induced otitis media with effusion. Tritium water was administered through intravenous injection and transference of tritium water into the middle ear cavity was measured by radioactivity of the middle ear perfusate. Morphological changes were concurrently examined for comparison. Vascular permeability, as measured one, 7, and 14 days after occlusion of the eustachian tube, increased with time. A histological study showed an edematous hypertrophy of the submucosal tissue of the middle ear, suggesting a noticeable increase in microvascular permeability. The response of the middle ear mucosa to histamine, which was added to the fluid for perfusion, gradually decreased after occlusion of the eustachian tube, although the effect of histamine tended to persist for a long time, irrespective of the amount of administration. The results indicated that the mucosal membrane of the middle ear has a noticeable permeability at least up to 14 days after occlusion, and that histamine may be responsible for the increase of submucosal microvascular permeability not only in the normal middle ear cavity but also in otitis media with effusion which results in the persistance of the disease. The presence of factors permeable to the blood, other than histamine, caused microvascular peameability to increase, probably resulting in chronic or irreversible inflammation. This may be explained by markedly proliferative or parenchymatous connective tissues observed 7 and l0 weeks after occlusion. It should be noted that surgical treatment be performed as early as possible in the case of otitis media with effusion. (Namekawa, K) 80 refs.

  15. Directed assembly of three-dimensional microvascular networks

    Science.gov (United States)

    Therriault, Daniel

    Three-dimensional (3-D) microvascular networks with pervasive, interconnected channels less than 300 mum in diameter may find widespread application in microfluidic devices, biotechnology, sensors, and autonomic healing materials. Although microchannel arrays are readily constructed in two-dimensions by photolithographic or soft lithographic techniques, their construction in three-dimensions remains a challenging problem. The development of a microfabrication method to build 3-D microvascular networks based on direct-write assembly is described is this thesis. The method is based on the robotic deposition of a fugitive organic ink to form a free-standing scaffold structure. Secondary infiltration of a structural resin followed by setting of the matrix and removal of the scaffold yields an embedded pervasive network of smooth cylindrical channels (˜10--500 mum) with defined connectivity. Rheological and other material properties studies of fugitive organic ink were performed in order to identify the critical characteristics required for successful deposition of 3-D scaffolds by direct-write assembly. Guided by the results of these studies, several new ink formulations were screened for improved deposition performance. The most successful of these inks (40wt% microcrystalline wax, 60wt% petroleum jelly) showed excellent deposition and had an equilibrium modulus at room temperature (G 'eq ˜ 7.70 kPa 1 Hz) nearly two orders of magnitude higher than the original ink. The optimized ink was used to successfully build thick (i.e., ˜100 layers) scaffold structures at room temperature with negligible time-dependent deformation post-deposition. Secondary infiltration of the resin was accomplished at room temperature while maintaining the scaffold architecture. The optimized ink was also successfully extruded through small micronozzles (1 mum). The construction of 3-D microvascular networks enables microfluidic devices with unparallel geometric complexity. In one example, a

  16. Intrinsic sex-specific differences in microvascular endothelial cell phosphodiesterases

    Science.gov (United States)

    Bingaman, Susan; Huxley, Virginia H.

    2010-01-01

    The importance of gonadal hormones in the regulation of vascular function has been documented. An alternate and essential contribution of the sex chromosomes to sex differences in vascular function is poorly understood. We reported previously sex differences in microvessel permeability (Ps) responses to adenosine that were mediated by the cAMP signaling pathway (Wang J, PhD thesis, 2005; Wang J and Huxley V, Proceedings of the VIII World Congress of Microcirculation, 2007; Wang J and Huxley VH, Am J Physiol Heart Circ Physiol 291: H3094–H3105, 2006). The two cyclic nucleotides, cAMP and cGMP, central to the regulation of vascular barrier integrity, are hydrolyzed by phosphodiesterases (PDE). We hypothesized that microvascular endothelial cells (EC) would retain intrinsic and inheritable sexually dimorphic genes with respect to the PDEs modulating EC barrier function. Primary cultured microvascular EC from skeletal muscles isolated from male and female rats, respectively, were used. SRY (a sex-determining region Y gene) mRNA expression was observed exclusively in male, not female, cells. The predominant isoform among PDE1–5, present in both XY and XX EC, was PDE4. Expression mRNA levels of PDE1A (male > female) and PDE3B (male < female) were sex dependent; PDE2A, PDE4D, and PDE5A were sex independent. Barrier function, Ps, was determined from measures of albumin flux across confluent primary cultured microvessel XY and XX EC monolayers. Consistent with intact in situ microvessels, basal monolayer Ps did not differ between XY (1.7 ± 0.2 × 10−6 cm/s; n = 8) and XX (1.8 ± 0.1 × 10−6 cm/s; n = 10) EC. Cilostazol, a PDE3 inhibitor, reduced (11%, P < 0.05) Ps in XX, not XY, cells. These findings demonstrate the presence and maintenance of intrinsic sex-related differences in gene expression and cellular phenotype by microvascular EC in a gonadal-hormone-free environment. Furthermore, intrinsic cell-sex likely contributes significantly to sexual dimorphism in

  17. The role of abnormal muscle response monitoring during microvascular decompression for treating hemifacial spasm

    Directory of Open Access Journals (Sweden)

    Xiao-chen CHEN

    2016-05-01

    Full Text Available Objective To investigate the significance of abnormal muscle response (AMR monitoring during microvascular decompression (MVD for hemifacial spasm (HFS in confirming the responsible blood vessel, improving the prognosis and reducing postoperative complications.  Methods A total of 34 HFS patients underwent AMR monitoring during MVD.  Results The AMR of mentalis was recorded in all 34 patients by electrically stimulating zygomatic branch of facial nerve before anesthesia. Compared with preoperation, the AMR latency after operation was significantly longer [(16.12 ± 3.17 ms vs (14.75 ± 3.32 ms, P = 0.015] and amplitude was significantly reduced [(0.11 ± 0.03)mV vs (0.13 ± 0.03 mV, P = 0.027]. AMR was disappeared in 32 cases (94.12% after the removal of responsible blood vessel. There was one patient (2.94% whose AMR disappeared momentarily after the incision of endocranium and disappeared completely after the removal of responsible blood vessel, while AMR still existed in one case (2.94% after the removal of responsible blood vessel. Responsible blood vessels included anterior inferior cerebellar artery (N = 30, 88.24%, posterior inferior cerebellar artery (N = 3, 8.82% and basilar artery (N = 1, 2.94%, which oppressed the root of facial nerve (N = 22, 64.71%, the distal part (N = 8, 23.53%, and both the root and distal part (N = 4, 11.76%. After operation, facial spasm disappeared. Thirty-one cases were cured, 2 cases evidently remitted, and one case inefficacious. The total effective rate was 97.06%.  Conclusions Continuously intraoperative monitoring of AMR contributes to confirming the responsible blood vessel, completing decompression for facial nerve more thoroughly, improving the prognosis, reducing delayed healing up, at the same time enhancing neurosurgeons' confidence and reducing operation time. DOI: 10.3969/j.issn.1672-6731.2016.05.010

  18. Relationship Between Serum Zinc Level and Microvascular Complications in Patients with Type 2 Diabetes

    Institute of Scientific and Technical Information of China (English)

    Ying-Ying Luo; Jie Zhao; Xue-Yao Han; Xiang-Hai Zhou; Jing Wu; Li-Nong Ji

    2015-01-01

    Background: Previous studies suggested that zinc level was related to a certain diabetic microvascular complication.However, the relationship between zinc level and all the microvascular complications in type 2 diabetic patients remains unknown.The purpose of this study was to analyze the relationship between zinc level and each diabetic microvascular complication and identify the features related to low serum zinc level.Methods: We included the hospitalized patients with type 2 diabetes (T2D) at our department from May 30, 2013 to March 31, 2014.We initially compared the serum zinc levels between patients with specific microvascular complications and those without.We then analyzed the association between zinc level and each microvascular complication.Furthermore, we identified the unique features of patients with high and low serum zinc levels and analyzed the risk factors related to low zinc level.Results: The 412 patients included 271 with microvascular complications and 141 without any microvascular complications.Serum zinc level was significantly lower in patients with diabetic retinopathy (P < 0.001), diabetic nephropathy (DN, P < 0.001), or diabetic peripheral neuropathy (P =0.002) compared with patients without that specific complication.Lower zinc level was an independent risk factor for DN (odds ratio =0.869, 95% confidence interval =0.765-0.987, P < 0.05).The subjects with lower serum zinc level had manifested a longer duration of diabetes, higher level of hemoglobin A 1 c, higher prevalence of hypertension and microvascular complications, and lower fasting and 2-h C-peptide levels.Conclusions: Lower serum zinc level in T2D patients was related to higher prevalence of diabetic microvascular complications, and represented as an independent risk factor for DN.Patients with lower zinc level were more likely to have a longer duration of diabetes, poorer glucose control, and worse β-cell function.

  19. Altered microvascular hemodynamics during the induction and perpetuation of chronic gut inflammation.

    Science.gov (United States)

    Harris, Norman R; Whatley, Joseph R; Carter, Patsy R; Morgan, Georgia A; Grisham, Matthew B

    2009-04-01

    Adoptive transfer of naïve CD4+ T cells into lymphopenic mice induces chronic small and large bowel inflammation similar to Crohn's disease. Although much is now known regarding the immunopathology in this model of inflammatory bowel disease, virtually nothing is known about the microvascular hemodynamic changes during the induction and perpetuation of chronic gut inflammation. In this study, CD4+CD45RBhigh T cells obtained from healthy C57BL/6 donor mice were transferred into lymphopenic recombinase-activating gene-1-deficient (RAG knockout) mice, which induced small and large bowel inflammation. At various time points following reconstitution (3 days-9 wk), intravital microscopy was used to examine the microvessels in the submucosa of the ileum and proximal colon following infusion of fluorescently labeled platelets and injection of rhodamine 6G (to label leukocytes). Hemodynamic measurements and the extent of blood cell adhesion to the venular wall were compared with measurements in unreconstituted RAG knockout controls. In 50% compared with controls, with this decrease also observed at 4-5 and 7-9 wk postreconstitution. At 7-9 wk, arteriolar diameters were found to be approximately 15% larger than in controls, but, despite this dilation, flow rates in the individual vessels were decreased by approximately 30%. Venular platelet and leukocyte adherence were not significantly elevated above controls; however, an association was found between platelet adherence and venular shear rate. In summary, significant decreases in arteriolar velocity and shear rates are observed in this model of chronic gut inflammation.

  20. Glutathione in Cerebral Microvascular Endothelial Biology and Pathobiology: Implications for Brain Homeostasis

    Directory of Open Access Journals (Sweden)

    Wei Li

    2012-01-01

    Full Text Available The integrity of the vascular endothelium of the blood-brain barrier (BBB is central to cerebrovascular homeostasis. Given the function of the BBB as a physical and metabolic barrier that buffers the systemic environment, oxidative damage to the endothelial monolayer will have significant deleterious impact on the metabolic, immunological, and neurological functions of the brain. Glutathione (GSH is a ubiquitous major thiol within mammalian cells that plays important roles in antioxidant defense, oxidation-reduction reactions in metabolic pathways, and redox signaling. The existence of distinct GSH pools within the subcellular organelles supports an elegant mode for independent redox regulation of metabolic processes, including those that control cell fate. GSH-dependent homeostatic control of neurovascular function is relatively unexplored. Significantly, GSH regulation of two aspects of endothelial function is paramount to barrier preservation, namely, GSH protection against oxidative endothelial cell injury and GSH control of postdamage cell proliferation in endothelial repair and/or wound healing. This paper highlights our current insights and hypotheses into the role of GSH in cerebral microvascular biology and pathobiology with special focus on endothelial GSH and vascular integrity, oxidative disruption of endothelial barrier function, GSH regulation of endothelial cell proliferation, and the pathological implications of GSH disruption in oxidative stress-associated neurovascular disorders, such as diabetes and stroke.

  1. Characterization of tumor microvascular structure and permeability: comparison between magnetic resonance imaging and intravital confocal imaging

    Science.gov (United States)

    Reitan, Nina Kristine; Thuen, Marte; Goa, Pa˚L. Erik; de Lange Davies, Catharina

    2010-05-01

    Solid tumors are characterized by abnormal blood vessel organization, structure, and function. These abnormalities give rise to enhanced vascular permeability and may predict therapeutic responses. The permeability and architecture of the microvasculature in human osteosarcoma tumors growing in dorsal window chambers in athymic mice were measured by confocal laser scanning microscopy (CLSM) and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). Dextran (40 kDa) and Gadomer were used as molecular tracers for CLSM and DCE-MRI, respectively. A significant correlation was found between permeability indicators. The extravasation rate Ki as measured by CLSM correlated positively with DCE-MRI parameters, such as the volume transfer constant Ktrans and the initial slope of the contrast agent concentration-time curve. This demonstrates that these two techniques give complementary information. Extravasation was further related to microvascular structure and was found to correlate with the fractal dimension and vascular density. The structural parameter values that were obtained from CLSM images were higher for abnormal tumor vasculature than for normal vessels.

  2. Serum lipid profiles and dyslipidaemia are associated with retinal microvascular changes in children and adolescents

    Science.gov (United States)

    Xiao, Wei; Guo, Xinxing; Ding, Xiaohu; He, Mingguang

    2017-01-01

    The present study aims to assess the relationship between serum lipid parameters and retinal microvascular calibres in children and adolescents. A total of 950 participants aged 7 to 19 years were recruited. Central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were measured from digital retinal images. Serological testing was performed to obtain lipid profiles. Dyslipidaemia was defined according to the US national expert panel guideline. After adjusted for age, sex, mean arterial blood pressure, axial length, body mass index and the fellow retinal vascular calibre, no significant association was found between retinal vascular diameters and any lipid parameters (all P > 0.05) in children younger than 12 years. Among the adolescents 12 years and older, increased triglycerides, total cholesterol, low-density lipoprotein cholesterol, and apoB were associated with decrease in CRAE (β = −1.33, −1.83, −1.92 and −7.18, P = 0.031, 0.003, 0.006, and 0.009, respectively). Compared with normolipidemic counterparts, adolescents with dyslipidaemia had significantly narrower retinal arteriolar diameters. No significant relationship between lipid subclass levels and CRVE was revealed in adolescents. The present findings suggest that the elevation of atherogenic lipids in adolescents is closely related to the adverse changes of retinal arterioles. Dyslipidaemia may affect systemic microvasculature from childhood on. PMID:28317946

  3. Evaluation of the Microvascular Research Center Training Program for Assessing Microsurgical Skills in Trainee Surgeons

    Directory of Open Access Journals (Sweden)

    Seiji Komatsu

    2013-05-01

    Full Text Available Background  We established the Microvascular Research Center Training Program (MRCPto help trainee surgeons acquire and develop microsurgical skills. Medical students wererecruited to undergo theMRCP to assessthe effectiveness oftheMRCP fortrainee surgeons.Methods  Twenty-two medical students with no prior microsurgical experience, who completed the course from2005 to 2012,were included. TheMRCP comprises 5 stages oftraining,each with specific passing requirements. Stages 1 and 2 involve anastomosing silicone tubesand blood vessels of chicken carcasses,respectively,within 20minutes. Stage 3 involves anastomosing the femoral artery and vein oflive ratswith a 1-day patency rate of > 80%. Stage4 requires replantation of free superficial inferior epigastric artery flaps in rats with a 7-daysuccessrate of > 80%. Stage 5 involvessuccessful completion of one case ofratreplantation/transplantation. We calculated the passing rate for each stage and recorded the number ofanastomosesrequired to passstages 3 and 4.Results  The passing rates were 100% (22/22 for stages 1 and 2, 86.4% (19/22 for stage3, 59.1% (13/22 for stage 4, and 55.0% (11/20 for stage 5. The number of anastomosesperformedwas 17.2± 12.2 in stage 3 and 11.3± 8.1 in stage 4.Conclusions  Majority ofthemedicalstudentswho undertook theMRCP acquired basicmicrosurgicalskills. Thus,we conclude thatthe MRCP is an effective microsurgery training programfortrainee surgeons.

  4. Human brain microvascular endothelial cells resist elongation due to shear stress.

    Science.gov (United States)

    Reinitz, Adam; DeStefano, Jackson; Ye, Mao; Wong, Andrew D; Searson, Peter C

    2015-05-01

    Endothelial cells in straight sections of vessels are known to elongate and align in the direction of flow. This phenotype has been replicated in confluent monolayers of bovine aortic endothelial cells and human umbilical vein endothelial cells (HUVECs) in cell culture under physiological shear stress. Here we report on the morphological response of human brain microvascular endothelial cells (HBMECs) in confluent monolayers in response to shear stress. Using a microfluidic platform we image confluent monolayers of HBMECs and HUVECs under shear stresses up to 16 dyne cm(-2). From live-cell imaging we quantitatively analyze the cell morphology and cell speed as a function of time. We show that HBMECs do not undergo a classical transition from cobblestone to spindle-like morphology in response to shear stress. We further show that under shear stress, actin fibers are randomly oriented in the cells indicating that there is no cytoskeletal remodeling. These results suggest that HBMECs are programmed to resist elongation and alignment under shear stress, a phenotype that may be associated with the unique properties of the blood-brain barrier.

  5. An Unusual Case of Suspected Microvascular Angina in a Newborn

    Directory of Open Access Journals (Sweden)

    Stefania Cataldo

    2012-01-01

    Full Text Available Myocardial ischemia in pediatric population is uncommon and usually due to congenital heart disease or extracardiac conditions leading to poor coronary perfusion. A 6-day-old newborn presented with respiratory distress and signs of heart failure. ECG, echocardiography, and laboratory results were consistent with myocardial ischemia. Coronary angiography was performed to exclude anomalous origin of coronary arteries, showing normal coronary artery origin and course. Thrombophilia and extra-cardiac causes were ruled out. Clinical conditions improved with mechanical ventilation and diuretics, enzyme levels lowered, repolarisation and systolic function abnormalities regressed, but ischemic electrocardiographic and echocardiographic signs still presented during intense crying. Becaues of suspicion of microvascular angina, therapy with ASA and beta-blocker was started. At 5 month followup, the baby was in good clinical condition and no more episodes were recorded. We believe it is an interesting case, as no similar cases have been recorded till now.

  6. Intra-operative neurophysiology during microvascular decompression for hemifacial spasm.

    Science.gov (United States)

    Fernández-Conejero, I; Ulkatan, S; Sen, C; Deletis, V

    2012-01-01

    There is evidence that primary hemifacial spasm (HFS) in the majority of patients is related to a vascular compression of the facial nerve at its root exit zone (REZ). As a consequence, the hyperexcitability of facial nerve generates spasms of the facial muscles. Microvascular decompression (MVD) of the facial nerve near its REZ has been established as an effective treatment of HFS. Intra-operative disappearance of abnormal muscle responses (lateral spread) elicited by stimulating one of the facial nerve branches has been used as a method to predict MVD effectiveness. Other neurophysiologic techniques, such as facial F-wave, blink reflex and facial corticobulbar motor evoked potentials (FCoMEP), are feasible to intra-operatively study changes in excitability of the facial nerve and its nucleus during MVDs. Intra-operative neuromonitoring with the mentioned techniques allows a better understanding of HFS pathophysiology and helps to optimise the MVD.

  7. CMR of microvascular obstruction and hemorrhage in myocardial infarction

    Directory of Open Access Journals (Sweden)

    Wu Katherine C

    2012-09-01

    Full Text Available Abstract Microvascular obstruction (MO or no-reflow phenomenon is an established complication of coronary reperfusion therapy for acute myocardial infarction. It is increasingly recognized as a poor prognostic indicator and marker of subsequent adverse LV remodeling. Although MO can be assessed using various imaging modalities including electrocardiography, myocardial contrast echocardiography, nuclear scintigraphy, and coronary angiography, evaluation by cardiovascular magnetic resonance (CMR is particularly useful in enhancing its detection, diagnosis, and quantification, as well as following its subsequent effects on infarct evolution and healing. MO assessment has become a routine component of the CMR evaluation of acute myocardial infarction and will increasingly play a role in clinical trials of adjunctive reperfusion agents and strategies. This review will summarize the pathophysiology of MO, current CMR approaches to diagnosis, clinical implications, and future directions needed for improving our understanding of this common clinical problem.

  8. Statin use before diabetes diagnosis and risk of microvascular disease

    DEFF Research Database (Denmark)

    Nielsen, Sune F; Nordestgaard, Børge G

    2014-01-01

    BACKGROUND: The role of statins in the development of microvascular disease in patients with diabetes is unknown. We tested the hypothesis that statin use increases the risk of diabetic retinopathy, diabetic neuropathy, diabetic nephropathy, and gangrene of the foot in individuals with diabetes...... the cumulative incidence of diabetic retinopathy, diabetic neuropathy, diabetic nephropathy, or gangrene of the foot in statin users versus non-statin users. We analysed data with Cox regression models, adjusted for covariates including sex, age at diabetes diagnosis, and method of diabetes diagnosis. To address...... diabetic neuropathy, 1248 developed diabetic nephropathy, and 2392 developed gangrene of the foot. Compared with non-statin users, statin users had a lower cumulative incidence of diabetic retinopathy (hazard ratio 0·60, 95% CI 0·54-0·66; pdiabetic neuropathy (0·66, 0·57-0·75; p

  9. Polylactic Acid Nanoparticles Targeted to Brain Microvascular Endothelial Cells

    Institute of Scientific and Technical Information of China (English)

    WANG Huafang; HU Yu; SUN Wangqiang; XIE Changsheng

    2005-01-01

    In this work, blank polylactic acid (PLA) nanoparticles with unstained surface were prepared by the nano-deposition method. On the basis of the preparation, the effect of surface modification on brain microvascular endothelial cells (BMECs) targeting was examined by in vivo experiments and fluorescence microscopy. The results showed that PLA nanoparticles are less toxic than PACA nanoparticles but their BMECs targeting is similar to PACA nanoparticles. The experiments suggest that drugs can be loaded onto the particles and become more stable through adsorption on the surface of PLA nanoparticles with high surface activity. The surface of PLA nanoparticles was obviously modified and the hydrophilicity was increased as well in the presence of non-ionic surfactants on PLA nanoparticles. As a targeting moiety, polysobate 80 (T-80) can facilitate BMECs targeting of PLA nanoparticles.

  10. Modelo de suprimento sanguíneo do intestino grosso do tamanduá bandeira (Myrmecophaga tridactyla Model of blood supply to the intestine of Giant anteater (Myrmecophaga tridactyla

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Rezende de Souza

    2010-03-01

    Full Text Available Em seis animais adultos Myrmecophaga tridactyla estudou-se o modelo de suprimento sanguíneo do intestino grosso, que é dependente das artérias mesentérica cranial (AMCr e caudal (AMC. Os espécimes coletados conforme as normas do IBAMA (Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis foram perfundidos com água (40 C, injetados com látex corado, fixados em formol e conservados em solução alcoólica (50%. O mesocólon está disposto na linha sagital mediana e fixa o intestino grosso à parede dorsal do abdome. Derivaram da AMC: a artéria retal cranial, sete a 14 artérias cólicas e uma ou duas artérias ileocólicas, que apresentaram anastomoses de irrigação com a AMCr. A AMC finaliza-se na borda mesocólica das alças intestinais, emitindo ramos cólicos retos a partir das arcadas justacólicas, que penetram na intimidade da musculatura longitudinal. Ao longo do trajeto da AMC foram observadas ilhas arteriais, e a região ileocólica apresentou maior densidade vascular.This research aimed to study the model of large intestine blood supply, which is dependent on the cranial mesenteric artery (AMCr and caudal mesenteric artery (AMC, in six adults of Myrmecophaga tridactyla. The specimens were collected in accordance with the IBAMA standards (Brazilian Institute of the Environment and were perfused with water (40 C, injected with colored latex, fixed in formaldehyde and preserved in alcohol solution (50%. The mesocolon is positioned in the median sagittal line and fixes the large intestine to the dorsal wall of the abdomen. The following is derived from the AMC: the cranial rectal artery, from 7 to 14 colic arteries and one or two ileocolic arteries, which present irrigation anastomosis with AMCr. The AMC finishes at the mesocolic edge of the bowel loop, generating straight colic branches from juxtacolic arcades, which penetrate the intimacy of longitudinal muscles. Arterial islands were observed along the AMC

  11. 天麻素联合倍他司汀治疗椎基底动脉供血不足临床分析%Clinical analysis of treating vertebrobasilar insufficient blood supply with Tianmasu plus betahistine

    Institute of Scientific and Technical Information of China (English)

    杨东宁

    2013-01-01

      目的:观察天麻素注射液联合盐酸倍他司汀注射液治疗椎基底动脉供血不足引起的眩晕症状,在不同中医证型间的疗效差别。方法:对120例确诊为椎基底动脉供血不足且有眩晕症状的患者,均给予天麻素注射液联合盐酸倍他司汀注射液治疗,按中医辨证分为肝阳上亢组和其它证型组;观察两组患者的治疗效果。结果:肝阳上亢组治愈率明显高于其它证型组,二者相比差异具有显著性(P<0.05)。结论:天麻素注射液适用于肝阳上亢的眩晕症患者,在使用其治疗椎基底动脉供血不足引起的眩晕症状时也要遵循中医辨证论治的原则。%Objective:To observe the symptoms of vertigo caused by vertebrobasilar insufficient blood supply with Tianmasu plus betahistine and the effect differences between different syndrome types. Methods:120 cases were given Tianmasu plus betahistine injection, with Ganyang Shangkang group and other syndrome-type group. To observe the effect of the two groups. Results: The cure rate of the former was higher than the latter group. The difference was significant (P<0.05). Conclusion:Tianmasu injection applies to the vertigo of Ganyang Shangkang type, should follow the principles of TCM syndrome differentiation.

  12. Peroxynitrite mediates testosterone-induced vasodilation of microvascular resistance vessels.

    Science.gov (United States)

    Puttabyatappa, Yashoda; Stallone, John N; Ergul, Adviye; El-Remessy, Azza B; Kumar, Sanjiv; Black, Stephen; Johnson, Maribeth; Owen, Mary P; White, Richard E

    2013-04-01

    Our knowledge of how androgens influence the cardiovascular system is far from complete, and this lack of understanding is especially true of how androgens affect resistance vessels. Our aim was to identify the signaling mechanisms stimulated by testosterone (TES) in microvascular arteries and to understand how these mechanisms mediate TES-induced vasodilation. Mesenteric microvessels were isolated from male Sprague-Dawley rats. Tension studies demonstrated a rapid, concentration-dependent, vasodilatory response to TES that did not involve protein synthesis or aromatization to 17β-estradiol. Dichlorofluorescein fluorescence and nitrotyrosine immunoblot experiments indicated that TES stimulated peroxynitrite formation in microvessels, and functional studies demonstrated that TES-induced vasodilation was inhibited by scavenging peroxynitrite. As predicted, TES enhanced the production of both peroxynitrite precursors (i.e., superoxide and nitic oxide), and xanthine oxidase was identified as the likely source of TES-stimulated superoxide production. Functional and biochemical studies indicated that TES signaling involved activity of the phosphoinositide 3 (PI3) kinase-protein kinase B (Akt) cascade initiated by activation of the androgen receptor and culminated in enhanced production of cGMP and microvascular vasodilation. These findings, derived from a variety of analytical and functional approaches, provide evidence for a novel nongenomic signaling mechanism for androgen action in the microvasculature: TES-stimulated vasodilation mediated primarily by peroxynitrite formed from xanthine oxidase-generated superoxide and NO. This response was associated with activation of the PI3 kinase-Akt signaling cascade initiated by activation of the androgen receptor. We propose this mechanism could account for TES-stimulated cGMP production in microvessels and, ultimately, vasodilation.

  13. Uterine microvascular sensitivity to nanomaterial inhalation: An in vivo assessment.

    Science.gov (United States)

    Stapleton, P A; McBride, C R; Yi, J; Nurkiewicz, T R

    2015-11-01

    With the tremendous number and diverse applications of engineered nanomaterials incorporated in daily human activity, exposure can no longer be solely confined to occupational exposures of healthy male models. Cardiovascular and endothelial cell dysfunction have been established using in vitro and in situ preparations, but the translation to intact in vivo models is limited. Intravital microscopy has been used extensively to understand microvascular physiology while maintaining in vivo neurogenic, humoral, and myogenic control. However, a tissue specific model to assess the influences of nanomaterial exposure on female reproductive health has not been fully elucidated. Female Sprague Dawley (SD) rats were exposed to nano-TiO2 aerosols (171 ± 6 nm, 10.1 ± 0.39 mg/m(3), 5h) 24-hours prior to experimentation, leading to a calculated deposition of 42.0 ± 1.65 μg. After verifying estrus status, vital signs were monitored and the right horn of the uterus was exteriorized, gently secured over an optical pedestal, and enclosed in a warmed tissue bath using intravital microscopy techniques. After equilibration, significantly higher leukocyte-endothelium interactions were recorded in the exposed group. Arteriolar responsiveness was assessed using ionophoretically applied agents: muscarinic agonist acetylcholine (0.025 M; ACh; 20, 40, 100, and 200 nA), and nitric oxide donor sodium nitroprusside (0.05 M; SNP; 20, 40, and 100 nA), or adrenergic agonist phenylephrine (0.05 M; PE; 20, 40, and 100 nA) using glass micropipettes. Passive diameter was established by tissue superfusion with 10(-4)M adenosine. Similar to male counterparts, female SD rats present systemic microvascular dysfunction; however the ramifications associated with female health and reproduction have yet to be elucidated. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Uterine microvascular sensitivity to nanomaterial inhalation: An in vivo assessment☆

    Science.gov (United States)

    Stapleton, P.A.; McBride, C.R.; Yi, J.; Nurkiewicz, T.R.

    2015-01-01

    With the tremendous number and diverse applications of engineered nanomaterials incorporated in daily human activity, exposure can no longer be solely confined to occupational exposures of healthy male models. Cardiovascular and endothelial cell dysfunction have been established using in vitro and in situ preparations, but the translation to intact in vivo models is limited. Intravital microscopy has been used extensively to understand microvascular physiology while maintaining in vivo neurogenic, humoral, and myogenic control. However, a tissue specific model to assess the influences of nanomaterial exposure on female reproductive health has not been fully elucidated. Female Sprague Dawley (SD) rats were exposed to nano-TiO2 aerosols (171 ± 6 nm, 10.1 ± 0.39 mg/m3, 5 h) 24-hours prior to experimentation, leading to a calculated deposition of 42.0 ± 1.65 μg. After verifying estrus status, vital signs were monitored and the right horn of the uterus was exteriorized, gently secured over an optical pedestal, and enclosed in a warmed tissue bath using intravital microscopy techniques. After equilibration, significantly higher leukocyte-endothelium interactions were recorded in the exposed group. Arteriolar responsiveness was assessed using ionophoretically applied agents: muscarinic agonist acetylcholine (0.025 M; ACh; 20, 40, 100, and 200 nA), and nitric oxide donor sodium nitroprusside (0.05 M; SNP; 20, 40, and 100 nA), or adrenergic agonist phenylephrine (0.05 M; PE; 20, 40, and 100 nA) using glass micropipettes. Passive diameter was established by tissue superfusion with 10−4 M adenosine. Similar to male counterparts, female SD rats present systemic microvascular dysfunction; however the ramifications associated with female health and reproduction have yet to be elucidated. PMID:26375943

  15. Comprehensive Analysis of Chicken Vessels as Microvascular Anastomosis Training Model

    Science.gov (United States)

    Kang, Bo Young; Jeon, Byung-Joon; Lee, Kyeong-Tae

    2017-01-01

    Background Nonliving chickens are commonly used as a microvascular anastomosis training model. However, previous studies have investigated only a few types of vessel, and no study has compared the characteristics of the various vessels. The present study evaluated the anatomic characteristics of various chicken vessels as a training model. Methods Eight vessels—the brachial artery, basilic vein, radial artery, ulnar artery, ischiatic artery and vein, cranial tibial artery, and common dorsal metatarsal artery—were evaluated in 26 fresh chickens and 30 chicken feet for external diameter (ED) and thicknesses of the tunica adventitia and media. The dissection time from skin incision to application of vessel clamps was also measured. Results The EDs of the vessels varied. The ischiatic vein had the largest ED of 2.69±0.33 mm, followed by the basilic vein (1.88±0.36 mm), ischiatic artery (1.68±0.24 mm), common dorsal metatarsal artery (1.23±0.23 mm), cranial tibial artery (1.18±0.19 mm), brachial artery (1.08±0.15 mm), ulnar artery (0.82±0.13 mm), and radial artery (0.56±0.12 mm), and the order of size was consistent across all subjects. Thicknesses of the tunica adventitia and media were also diverse, ranging from 74.09±19.91 µm to 158.66±40.25 µm (adventitia) and from 31.2±7.13 µm to 154.15±46.48 µm (media), respectively. Mean dissection time was <3 minutes for all vessels. Conclusions Our results suggest that nonliving chickens can provide various vessels with different anatomic characteristics, which can allow trainees the choice of an appropriate microvascular anastomosis training model depending on their purpose and skillfulness. PMID:28194342

  16. Brain microvascular pericytes are immunoactive in culture: cytokine, chemokine, nitric oxide, and LRP-1 expression in response to lipopolysaccharide

    Directory of Open Access Journals (Sweden)

    Erickson Michelle A

    2011-10-01

    Full Text Available Abstract Background Brain microvascular pericytes are important constituents of the neurovascular unit. These cells are physically the closest cells to the microvascular endothelial cells in brain capillaries. They significantly contribute to the induction and maintenance of the barrier functions of the blood-brain barrier. However, very little is known about their immune activities or their roles in neuroinflammation. Here, we focused on the immunological profile of brain pericytes in culture in the quiescent and immune-challenged state by studying their production of immune mediators such as nitric oxide (NO, cytokines, and chemokines. We also examined the effects of immune challenge on pericyte expression of low density lipoprotein receptor-related protein-1 (LRP-1, a protein involved in the processing of amyloid precursor protein and the brain-to-blood efflux of amyloid-β peptide. Methods Supernatants were collected from primary cultures of mouse brain pericytes. Release of nitric oxide (NO was measured by the Griess reaction and the level of S-nitrosylation of pericyte proteins measured with a modified "biotin-switch" method. Specific mitogen-activated protein kinase (MAPK pathway inhibitors were used to determine involvement of these pathways on NO production. Cytokines and chemokines were analyzed by multianalyte technology. The expression of both subunits of LRP-1 was analyzed by western blot. Results Lipopolysaccharide (LPS induced release of NO by pericytes in a dose-dependent manner that was mediated through MAPK pathways. Nitrative stress resulted in S-nitrosylation of cellular proteins. Eighteen of twenty-three cytokines measured were released constitutively by pericytes or with stimulation by LPS, including interleukin (IL-12, IL-13, IL-9, IL-10, granulocyte-colony stimulating factor, granulocyte macrophage-colony stimulating factor, eotaxin, chemokine (C-C motif ligand (CCL-3, and CCL-4. Pericyte expressions of both subunits of

  17. Effects of electroacupuncture on microcirculatory blood flow and glucose transporter function in the hippocampus

    Institute of Scientific and Technical Information of China (English)

    Yan Lu; Bingbing Han; Shijun Wang

    2011-01-01

    Nerve cell metabolism in post brain ischemia depends on increased microcirculation perfusion and transport function of microvascular endothelial cells. In the present study, a rat model of middle cerebral artery occlusion was established to investigate the influence of electroacupuncture(EA)on hippocampal CA1 cerebral blood flow and glucose transporter 1(GLUT1)expression in the microvascular endothelial cp.lls. Following EA at Neiguan(PC 6), the cerebral blood flow in the ischemic hippocampal CA1 region was significantly elevated, the number and microvascular integrated absorbance of the GLUTl-positive cells were significantly increased, nerve cell damage was ameliorated, and GLUT1 protein expression in the ischemic hippocampus was significantly increased. Results demonstrate that EA increased the cerebral blood flow of the hippocampal CA1 region and improved the glucose transport function, thereby attenuating neuronal injuries.

  18. Role of Microvascular Tone and Extracellular Matrix Contraction in the Regulation of Interstitial Fluid: Implications for Aortic Dissection.

    Science.gov (United States)

    Mallat, Ziad; Tedgui, Alain; Henrion, Daniel

    2016-09-01

    The pathophysiology of aortic dissection is poorly understood, and its risk is resistant to medical treatment. Most studies have focused on a proposed pathogenic role of transforming growth factor-β in Marfan disease and related thoracic aortic aneurysms and aortic dissections. However, clinical testing of this concept using angiotensin II type 1 receptor antagonists to block transforming growth factor-β signaling fell short of promise. Genetic mutations that predispose to thoracic aortic aneurysms and aortic dissections affect components of the extracellular matrix and proteins involved in cellular force generation. Thus, a role for dysfunctional mechanosensing in abnormal aortic wall remodeling is emerging. However, how abnormal mechanosensing leads to aortic dissection remains a mystery. Here, we review current knowledge about the regulation of interstitial fluid dynamics and myogenic tone and propose that alteration in contractile force reduces vascular tone in the microcirculation (here, aortic vasa vasorum) and leads to elevations of blood flow, transmural pressure, and fluid flux into the surrounding aortic media. Furthermore, reduced contractile force in medial smooth muscle cells coupled with alteration of structural components of the extracellular matrix limits extracellular matrix contraction, further promoting the formation of intramural edema, a critical step in the initiation of aortic dissection. The concept is supported by several pathophysiological and clinical observations. A direct implication of this concept is that drugs that lower blood pressure and limit interstitial fluid accumulation while preserving or increasing microvascular tone would limit the risk of dissection. In contrast, drugs that substantially lower microvascular tone would be ineffective or may accelerate the disease and precipitate aortic dissection.

  19. Implementation of digital optical capillaroscopy for quantifying and estimating the microvascular abnormalities in type 2 diabetes mellitus

    Science.gov (United States)

    Gurfinkel, Yu. I.; Suchkova, O. V.; Sasonko, M. L.; Priezzhev, A. V.

    2016-04-01

    This study is aimed to define the extent of digital capillaroscopy possibilities for the quantification and estimation of microvascular abnormalities in type 2 diabetes mellitus (T2DM). A total of 196 adult persons were enrolled in the study including the group of compensated T2DM (n = 52), decompensated diabetics (n = 68), and healthy volunteers (n = 76) with normal blood glucose and without signs of cardiovascular pathology. All participants of the study were examined with the digital optical capillaroscope ("AET", Russia). This instrument is equipped with an image-processing program allowing for quantifying the diameters of the arterial and venous segments of the capillaries and their ratio (coefficient of remodeling), perivascular zone size, capillary blood velocity, and the degree of arterial loops narrowing and the density of the capillary network. Also we estimated the relative amount of coil-shaped capillaries. The study revealed significant difference in the capillary density and the remodeling coefficient in comparison of T2DM patients with non-diabetic individuals. Significant changes are found in the decompensated T2DM group compared to the compensated group of diabetic patients. Furthermore, the number of coil-shaped capillaries differed greatly in T2DM patients as compared to the healthy subjects. The study did not reveal any statistically significant differences in the capillary density between the patients with compensated and decompensated T2DM. The digital optical capillaroscope equipped with the advanced image-processing algorithm opens up new possibilities for obtaining clinically important information on microvascular abnormalities in patients suffering from diabetes mellitus.

  20. Establishment of an in vitro blood-brain barrier model by co-culturing rat brain microvascular endothelial cells,pericytes and astrocytes%大鼠脑微血管内皮细胞与周细胞、星形胶质细胞共培养建立体外血脑屏障模型

    Institute of Scientific and Technical Information of China (English)

    查雨锋; 傅晓钟; 张顺; 罗敏; 欧瑜; 董永喜; 王爱民; 王永林

    2015-01-01

    目的:应用原代培养的大鼠脑微血管内皮细胞(brain-microvessel endothelial cells,BMECs )与脑微血管周细胞(brain-microvessel pericytes,BMPC )、星形胶质细胞(astro-cytes,AS)共培养建立可模拟在体状态的体外血脑屏障(blood-brain barrier,BBB)模型。方法原代分离、纯化和培养大鼠BMECs、BMPC和AS,通过细胞形态学和免疫细胞化学染色方法鉴定原代培养的细胞,应用Millicell细胞培养插(孔径0.4μm)建立5种不同类型的体外BBB模型,经跨内皮电阻值(transendothelial electrical resistance,TEER)、荧光素钠通透性(sodium fluorescent,Na-FLU )、碱性磷酸酶(AKP)和γ-谷氨酰转肽酶(γ-GT1)的表达测定以及阳性药在体内和体外BBB通透量的相似性,比较评价其屏障功能。结果原代培养的BMECs呈典型的铺路卵石样结构,BMPC胞体较大且呈分枝状,AS 有细长突触,胞质较浅;免疫细胞化学染色证实原代细胞为目标细胞;BMECs与BMPC、AS共培养后TEER值可达(478±25)Ω·cm2,Na-FLU 的表观渗透系数为[(8.23±0.78)×10-6]cm·s-1,AKP和γ-GT1表达分别为(6.90±0.27)金氏单位· g-1 Pro,(4.39±0.32)μg·g-1 Pro;阳性药在体外BBB的表观渗透系数(apparent permeability coefficient,Papp )与在体数据具有较好的相关性(R2=0.92)。结论原代培养的大鼠BMECs与BMPC、AS共培养建立的体外BBB模型在形态、结构及屏障功能方面具备BBB的基本特征,为研究BBB的生理学、病理学以及筛选化合物提供了一种有用工具。%Aim To establish in vitro blood-brain barrier (BBB) model with characteristics of simulation of in vivo BBB by primi-tive co-culture of brain-microvessel endothelial cells (BMECs) with brain-microvessel pericytes (BMPC)and astrocytes (AS). Methods BMECs,BMPC and AS from SD rats were primitively isolated,purified and cultured,and then

  1. Zika Virus Persistently Infects and Is Basolaterally Released from Primary Human Brain Microvascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Megan C. Mladinich

    2017-07-01

    Full Text Available Zika virus (ZIKV is a mosquito-borne Flavivirus that has emerged as the cause of encephalitis and fetal microencephaly in the Americas. ZIKV uniquely persists in human bodily fluids for up to 6 months, is sexually transmitted, and traverses the placenta and the blood-brain barrier (BBB to damage neurons. Cells that support persistent ZIKV replication and mechanisms by which ZIKV establishes persistence remain enigmatic but central to ZIKV entry into protected neuronal compartments. The endothelial cell (EC lining of capillaries normally constrains transplacental transmission and forms the BBB, which selectively restricts access of blood constituents to neurons. We found that ZIKV (strain PRVABC59 persistently infects and continuously replicates in primary human brain microvascular ECs (hBMECs, without cytopathology, for >9 days and following hBMEC passage. ZIKV did not permeabilize hBMECs but was released basolaterally from polarized hBMECs, suggesting a direct mechanism for ZIKV to cross the BBB. ZIKV-infected hBMECs were rapidly resistant to alpha interferon (IFN-α and transiently induced, but failed to secrete, IFN-β and IFN-λ. Global transcriptome analysis determined that ZIKV constitutively induced IFN regulatory factor 7 (IRF7, IRF9, and IFN-stimulated genes (ISGs 1 to 9 days postinfection, despite persistently replicating in hBMECs. ZIKV constitutively induced ISG15, HERC5, and USP18, which are linked to hepatitis C virus (HCV persistence and IFN regulation, chemokine CCL5, which is associated with immunopathogenesis, as well as cell survival factors. Our results reveal that hBMECs act as a reservoir of persistent ZIKV replication, suggest routes for ZIKV to cross hBMECs into neuronal compartments, and define novel mechanisms of ZIKV persistence that can be targeted to restrict ZIKV spread.

  2. Restoring microvascular efficiency with mesoglycan in women affected by moderate chronic venous disease.

    Science.gov (United States)

    Maresca, L; Foggia, C; Leonardo, G

    2015-04-01

    Chronic venous disorders (CVDs) subtend a spectrum of vascular abnormalities, including microcirculation and skin damages (as ulcers) in the lower limb. Mesoglycan has been established as an effective agent to improve microcirculation associated with CVDs. The aim of this study was to determine the beneficial function of mesoglycan on cutaneous blood flow measured by laser Doppler fluometry (LDF) before and after iontophoresis analysis using methacholine chloride (MCh) injection in a group of female patients in different stages of CVDs, according to the CEAP classification. Female patients with chronic venous disorders (CVD) were referred from primary care practices and vascular clinics. The study selected 75 women aged 45.5 ± 9.6 years (range, 30 to 60 years). And grading in CEAP classification. Eligible patients were allocated consecutively, according to entrance order, in an active treatment group and in a control group for 90 days. The active group (N. = 37) received mesoglycan 50 mg twice daily in adjunct to standard care. The primary outcome variable for the study was the measurement of skin microcirculation blood flow by LDF. Data obtained was transferred to a database (Excel) and analysed using statistical software (SPSS version 12, SPSS, USA). After 90 days of treatment, mesoglycan obtained a significative increase in peak flow at LDF of about 13% respect of baseline and standard care in the entire group of CVD treated women. In upper CEAP classes there was a trend for a more intense vasodilating activity of mesoglycan. The study shows improving in microvascular function induced by a 3-month mesoglycan treatment in patients classified by CEAP stages C1 and C4.

  3. Security of supply

    OpenAIRE

    2007-01-01

    Paul Isbell revisits the energy security debate; John Gault considers European security and natural gas supplies; William C. Ramsay discusses security of energy supplies in a global market; Hasan M. Qabazard outlines OPEC’s abiding commitment to energy security.