Effects of neuropeptides and vasoactive substances on microcirculation of the callus after tibial osteotomy in rabbits

2009 ◽  
Vol 57 (3) ◽  
pp. 427-439
Author(s):  
Zsolt Vendégh ◽  
András Melly ◽  
Balázs Tóth ◽  
Konrad Wolf ◽  
Tamás Farkas ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Perfusion Pressure ◽  
Tibial Osteotomy ◽  
Peripheral Vascular ◽  
Flow Measurements ◽  
Vasoactive Substances ◽  
Blood Flow Measurements

Previous studies have demonstrated a dynamic ingrowth of vessels into the developing callus. In this study, maturation and development of the regulation of microcirculation were followed in the callus of rabbits. In the first series, the effects of vasoactive substances on blood flow velocity, perfusion pressure, duration of effects and peripheral vascular resistance of the bone marrow in the femur and tibia were compared. In the second series, the same parameters were measured in the femur and in the developing callus 10 and 15 days following gap osteotomy of the tibia. There were no significant differences between the microcirculatory reactions of the intact femur and tibia. Basal blood flow could be verified in the callus on the 10th postoperative day. No vascular reactions could be elicited. Basal blood flow velocity was higher on the 15th day, when compared to the measurements on the 10th day. The substances elicited statistically significant differences in flow velocity, resistance and 50% recovery time in the callus on the 15th day. Blood flow reactions of the ipsilateral femoral and tibial bone marrow are identical, thus the femur can serve as a reference site for blood flow measurements in the callus. Regulation and maturation of callus microcirculation develop rapidly between the 10th and 15th days.

Brain Blood Flow

PEDIATRICS ◽  
1984 ◽  
Vol 74 (2) ◽  
pp. 317-317
Author(s):  
NANCY B. HANSEN ◽  
BARBARA S. STONESTREET ◽  
TED S. ROSENKRANTZ ◽  
WILLIAM OH
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Cerebral Blood Flow Velocity ◽  
Brain Blood Flow ◽  
Flow Measurements ◽  
Correlation Data ◽  
Microsphere Method ◽  
Blood Flow Measurements

In Reply.— We appreciate Rosenfeld's comments on our paper on the validity of Doppler measurements of anterior cerebral artery blood flow velocity. Rosenfeld raised two points regarding the validity of our correlation data between Doppler technique and cerebral blood flow measurements by the microsphere method. (1) Rosenfeld correctly pointed out that when we relate brain blood flow to any of the parameters obtained in the measurement of cerebral blood flow velocity, there is considerable variation in the values observed.

Ocular and Orbital Blood Flow Velocity in Patients with Peripheral Vascular Disease and Diabetes Treated with Intravenous Prostaglandin E1

2001 ◽  
Vol 17 (6) ◽  
pp. 529-535 ◽  
Author(s):  
Robert D. Steigerwalt ◽  
Gianni V. Belcaro ◽  
Vichy Christopoulos ◽  
Lucrezia Incandela ◽  
Maria Rosaria Cesarone ◽  
...  
Keyword(s):  
Blood Flow ◽  
Vascular Disease ◽  
Flow Velocity ◽  
Peripheral Vascular Disease ◽  
Blood Flow Velocity ◽  
Prostaglandin E1 ◽  
Peripheral Vascular

Cerebral pressure-flow relations in hypertensive elderly humans: transfer gain in different frequency domains

2005 ◽  
Vol 98 (1) ◽  
pp. 151-159 ◽  
Author(s):  
Jorge M. Serrador ◽  
Farzaneh A. Sorond ◽  
Mitul Vyas ◽  
Margaret Gagnon ◽  
Ikechukwu D. Iloputaife ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Transfer Function ◽  
Flow Velocity ◽  
Elderly People ◽  
Blood Flow Velocity ◽  
Perfusion Pressure ◽  
Cerebral Blood Flow Velocity ◽  
Pressure Changes

The dynamics of the cerebral vascular response to blood pressure changes in hypertensive humans is poorly understood. Because cerebral blood flow is dependent on adequate perfusion pressure, it is important to understand the effect of hypertension on the transfer of pressure to flow in the cerebrovascular system of elderly people. Therefore, we examined the effect of spontaneous and induced blood pressure changes on beat-to-beat and within-beat cerebral blood flow in three groups of elderly people: normotensive, controlled hypertensive, and uncontrolled hypertensive subjects. Cerebral blood flow velocity (transcranial Doppler), blood pressure (Finapres), heart rate, and end-tidal CO2 were measured during the transition from a sit to stand position. Transfer function gains relating blood pressure to cerebral blood flow velocity were assessed during steady-state sitting and standing. Cerebral blood flow regulation was preserved in all three groups by using changes in cerebrovascular resistance, transfer function gains, and the autoregulatory index as indexes of cerebral autoregulation. Hypertensive subjects demonstrated better attenuation of cerebral blood flow fluctuations in response to blood pressure changes both within the beat (i.e., lower gain at the cardiac frequency) and in the low-frequency range (autoregulatory, 0.03–0.07 Hz). Despite a better pressure autoregulatory response, hypertensive subjects demonstrated reduced reactivity to CO2. Thus otherwise healthy hypertensive elderly subjects, whether controlled or uncontrolled with antihypertensive medication, retain the ability to maintain cerebral blood flow in the face of acute changes in perfusion pressure. Pressure regulation of cerebral blood flow is unrelated to cerebrovascular reactivity to CO2.

Cerebrovascular CO2Reactivity during Anesthesia in Patients with Diabetes Mellitus and Peripheral Vascular Disease 

1998 ◽  
Vol 89 (4) ◽  
pp. 887-893 ◽  
Author(s):  
Ryuichi Kawata ◽  
Kazuhiko Nakakimura ◽  
Mishiya Matsumoto ◽  
Kouji Kawai ◽  
Mitsuru Kunihiro ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Carbon Dioxide ◽  
Blood Flow ◽  
Vascular Disease ◽  
Flow Velocity ◽  
Peripheral Vascular Disease ◽  
Blood Flow Velocity ◽  
Control Group ◽  
Peripheral Vascular ◽  
Carbon Dioxide Reactivity

Background Diabetes mellitus (DM) and systemic atherosclerosis are risk factors for stroke. Although the origins of increased risk are complex, one possibility is that cerebrovascular reactivity is impaired and does not allow the brain to compensate for aberrations in physiology. The current study tested this issue by evaluating mean blood flow velocity of the middle cerebral artery (Vmca) and carbon dioxide reactivity during anesthesia in patients with DM and peripheral vascular disease (PVD). Methods Fifty-two patients were observed: 20 patients with DM (the DM group), 12 patients with PVD (the PVD group), and 20 patients classified as American Society of Anesthesiologists physical status 1 or 2 (the control group). The Vmca was measured using transcranial Doppler ultrasonography during isoflurane-nitrous oxide anesthesia. After measuring baseline Vmca at a partial pressure of carbon dioxide in arterial blood (PaCO2) of 37.7 +/- 4.5 mmHg (mean +/- SD), measurements were repeated at a PaCO of 44.2 +/- 3.8 mmHg, and the carbon dioxide reactivity (absolute value: cm x s(-1) x mmHg(-1); relative value: percentage of baseline Vmca/mmHg) was calculated. Results The baseline Vmca of the DM group (51 +/- 12 cm/s) was significantly greater than those of the control group (42 +/- 6 cm/s) and the PVD group (42 +/- 13 cm/s). The absolute and relative values of carbon dioxide reactivity in the DM group (3.1 +/- 1.3 cm x s(-1) x mmHg(-1); 6.3 +/- 2.4%/mmHg) were significantly greater than or equivalent to those of the control group (2.3 +/- 0.8 cm x s(-1) x mmHg(-1); 5.3 +/- 1.7%/mmHg), respectively. In the PVD group, the baseline Vmca was equivalent to the control group, but the carbon dioxide reactivity (1.1 +/- 0.5 cm x s(-1) x mmHg(-1) 2.8 +/- 1.2%/mmHg) was significantly less. Conclusions The patients with DM have increased baseline cerebral blood flow velocity and normal carbon dioxide reactivity during anesthesia. The patients with PVD have decreased carbon dioxide reactivity, but baseline flow velocity is maintained.

scholarly journals Fetal blood flow velocity waveforms in relation to changing peripheral vascular resistance

1987 ◽  
Vol 15 (2) ◽  
pp. 119-127 ◽  
Author(s):  
M.J. Noordam ◽  
J.W. Wladimiroff ◽  
F.K. Lotgering ◽  
P.C. Struijk ◽  
H.M. Tonge
Keyword(s):  
Blood Flow ◽  
Flow Velocity ◽  
Vascular Resistance ◽  
Blood Flow Velocity ◽  
Peripheral Vascular Resistance ◽  
Fetal Blood ◽  
Peripheral Vascular

scholarly journals Positron emission tomographic measurement of bone marrow blood flow to the pelvis and lumbar vertebrae in young normal adults [published erratum appears in Blood 1994 Nov 15;84(10):3602]

Blood ◽  
1994 ◽  
Vol 83 (4) ◽  
pp. 958-963 ◽  
Author(s):  
D Kahn ◽  
GJ Weiner ◽  
S Ben-Haim ◽  
LL Ponto ◽  
MT Madsen ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Blood Flow ◽  
Lumbar Vertebrae ◽  
Individual Subject ◽  
Flow Measurements ◽  
Lumbar Vertebral Body ◽  
Positron Emission ◽  
Blood Flow Measurements ◽  
Normal Adults ◽  
Bone Marrow Blood

Abstract Ten young normal adults had pelvic and lumbar vertebral body bone marrow blood flow examined using [15O]water and positron emission tomography (PET) in a study designed to assess the feasibility and reproducibility of the PET technique for measuring marrow blood flow to various marrow regions. The procedure was well tolerated. Repeated blood flow measurements obtained from two consecutive [15O]water exams on each individual subject were highly reproducible. In addition, there was minimal variation in marrow blood flow from individual to individual and no gender differences were noted. In contrast, mean+/-SD bone marrow blood flows (expressed as milliliters per minute per 100 g) at selected anatomical sites were significantly different and were as follows: lower lumbar vertebral bodies, 17.6+/-3.1; most posterior and superior pelvis (conventional site of percutaneous bone marrow biopsy), 14.3+/-3.1; and total superior pelvis, 11.1+/-2.0. We conclude that PET is a relatively noninvasive, simple, and reproducible technique for measuring bone marrow blood flow. Marrow blood flow is consistent between normal young subjects, but varies significantly between different anatomic regions of the marrow.

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