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PubMed1996

[The effect of chemical sympathectomy on the adrenergic innervation of the blood vessels belonging to different organs in salt-sensitive and salt-resistant Dahl-strain rats].

The action of chemical desympathization by 6-hydroxydophamine influencing adrenergic innervation in different organs vessels (mesenterial, renal and femoral) was studied using histochemical fluorescent method in salt susceptible and salt-resistant Dahl rats kept on a low- and high-salt diet. Heterogeneity of adrenergic innervation of different region vessels was established to display and 6-hydroxydophamine caused complete desympathization only in mesenterial artery and in all veins, while in renal artery retained adrenergic plexus its certain branching and femoral artery-in two thirds of its surface. The process of reinnervation in vessels running with different intensity in different animals and in different vessels was found to start in vessels of majority of animals on day 5-6 after the chemical desympathization. 6-hydroxydophamine had greater impact on the vessels of salt-susceptible high salt rat (hypertension) and salt-resistant high-salt-diet (normension) rats. Thus, the state of arterial and venous adrenergic apparatus in hypertension Dahl rats is determined not by the increased blood pressure itself but by the natrium metabolism disturbance.

Adrenergic Fibers↗

PubMed1998

Number of perifoveal vessels in aging, hypertension, and atherosclerosis: the Rotterdam Study.

PURPOSE: To assess the associations among age, gender, hypertension, atherosclerosis, combined hypertension and atherosclerosis, and the number of perifoveal retinal arterioles and venules in the general elderly population. METHODS: A cross-sectional study was performed among subjects ranging in age from 55 to 74 years who participated in the population-based Rotterdam Study. Perifoveal vessels were counted in a masked way by two observers within 1500 microm from the foveola on fundus transparencies of 34 cases with hypertension, 55 with lower extremity arterial disease (LEAD), 27 with hypertension and LEAD, and 194 control subjects without either condition. Multiple linear regression analysis was used to study the associations. RESULTS: The mean number of perifoveal vessels was 12.0 (SD 2.0). The number of perifoveal vessels decreased with age in all groups, with an average of 0.4 per 5 years (95% confidence interval [CI], 0.2, 0.6, P=0.001). In women, the number of perifoveal vessels was on average 0.8 (95% CI, 0.3, 1.2, P=0.002) lower than in men. Patients with hypertension had a significantly lower number of vessels compared with control subjects: mean reduction 1.0 (95% CI, 0.2, 1.7), independent of age and sex. Patients with LEAD had 1.0 (95% CI, 0.4, 1.6) fewer perifoveal vessels, whereas the number in those with hypertension and LEAD was 1.8 (95% (CI, 1.0, 2.6) lower. Additional adjustment for established cardiovascular risk factors did not materially alter the findings. CONCLUSIONS: Increasing age, female gender, systemic hypertension, and LEAD were associated with a lower number of perifoveal arterioles and venules in the elderly.

Aged↗

PubMed1999

Anatomical study of the perforating vessels of the lower leg.

Difficulty of soft tissue defects of the lower leg demands the development of new methods to treat such defects. The aim of this study is the examination of perforators and the various ways of blood supply to the skin in the lower leg. Provided with certain regularity, we would be able to cure soft-tissue defects also in the difficult zone of the distal segment and on the dorsum of the foot not harming vessels and not affecting mobility of muscles. Subcutaneous island-flaps supplied by perforating vessels could replace free flaps. By saving the crural fascia of 10 lower legs we flayed layers of skin and fat, marked the perforating vessels with pins, and photographed and documented them. Specimens were divided into a proximal, an intermediate and a distal segment, each of them subdivided into a medial, lateral and dorsal section. The perforators, which can be classified as septocutaneous and musculocutaneous vessels, followed a reproducible pattern all over the lower leg. All vessels were sufficient in number as well as in size. Additionally these perforators can easily be identified by colour-coded sonography. The knowledge that perforators in the lower leg occur regularly enables the development of a new operative approach in therapy of soft-tissue defects in this region with the advantage, that the vessels used can be selected preoperatively.

Adipose Tissue↗

PubMed2001

Visualization of blood flow in hepatic vessels and hepatocellular carcinoma using B-flow sonography.

PURPOSE: A B-flow sonographic technique was recently developed to provide direct visualization of blood flow with gray-scale sonography. Compared with color Doppler sonography, B-flow imaging has wideband resolution and a high frame rate. The purpose of this study was to evaluate the usefulness of B-flow sonography for visualizing blood flow in hepatic vessels and tumor vascularity in patients with liver cirrhosis or hepatocellular carcinoma (HCC). METHODS: Twenty-five patients with liver cirrhosis, including 15 with HCC, were studied by B-flow and color Doppler sonography. Blood-flow detection rates in portal veins and hepatic arteries and tumor vascularity in HCC were analyzed, and the 2 methods were compared. RESULTS: Using B-flow, blood flow was visualized in the portal vein in 23 (92%) of 25 patients and was visualized in the hepatic artery separately from the portal vein in 9 (36%) of 25 patients. The blood-flow signals were visualized only within vessels, never "bleeding" outside the vessel's lumen. Blood flow in the portal vein was observed with color Doppler sonography in all 25 patients, but the hepatic artery was never clearly separated from the portal vein. Vascularity within the HCC tumor was detected in 9 (60%) of 15 nodules with B-flow imaging, and fine arteries flowing into the tumor were observed in 6 nodules. Color Doppler sonography detected blood flow in 13 (87%) of the 15 HCC nodules. CONCLUSIONS: Blood flow in hepatic vessels and tumor vessels of HCC were visualized with B-flow sonography. B-flow sonography is a potentially useful technique for the evaluation of liver vascularity and intratumoral vessels.

Aged↗

PubMed1990

Tumor angiogenesis formation of vessels de novo at germ cell tumors.

Systemic studies of 346 biopsy specimens and 56 necropsy specimens with testicular germ cell tumors established two types of vessel formation: (1) classic (mature) type, representing a proliferation of the vessel system that already exists; and (2) embryonal type, with a real new formation of vessels from giant multinuclear cells. Vessels and vessel convolutes with wide lumina and thin walls are characteristic of the embryonal type. Essential properties of both types of vessel formation are presented, as well as the gradual transformation of giant multinuclear cells. The way that giant cell formations are created is described, along with their role in the tumor angiogenesis.

Humans↗

PubMed2002

Long-term clinical outcomes after coronary angioplasty using long stents in small coronary vessels.

The role of coronary stenting in challenging situations, such as small vessels and long lesions, remains controversial. The aim of this study was to examine the procedural, in-hospital, and long-term clinical outcomes of patients undergoing angioplasty with long stents in small coronary vessels. We evaluated the procedural success rate and clinical outcomes in 252 consecutive subjects treated by means of the implantation of a single coronary stent in vessels with a mean reference diameter of < 2.5 mm; 128 patients received a short stent (< or = 16 mm) and 124 a long stent (> or = 18 mm). Lesion morphology was more complex in patients treated with long stents (P < 0.05). The mean stent length was 14 +/- 2 mm in the short-stent group and 25 +/- 3 mm in the long-stent group (P < 0.001). The overall procedural success rate (98.4% vs. 97.6%; P = NS) and the rate of major in-hospital adverse events (death, acute myocardial infarction, or target vessel revascularization; 1.6% vs. 2.4%; P = NS) was similar in the two groups. After 11.7 +/- 7 months of follow-up, there was no difference in the incidence of mortality and myocardial infarction (5% vs. 6.6%; P = NS), but revascularization tended to occur more frequently in the patients treated with long stents (21.7% vs. 13.9%; P = NS). In conclusion, the procedural success rate of single short or long stents in small coronary vessels was similar. Although the incidence of target vessel revascularization tended to be higher in the patients treated with longer stents, 2-year event-free survival was equivalent in the two groups (65% vs. 70%; P = NS).

Aged↗

PubMed2004

Cutting balloon angioplasty of the popliteal and infrapopliteal vessels for symptomatic limb ischemia.

Options for lower limb percutaneous revascularization are limited especially for complex vessel obstruction. Cutting balloon angioplasty (CBA) has been described in the coronary literature as effective for complex disease. We analyzed our peripheral vascular database and report procedural outcomes along with the clinical success at a mean of 1-year follow-up in 73 patients with symptomatic lower limb ischemia undergoing CBA. CBA was successfully completed in all 73 patients (93 vessels; 100%) with predilation necessary in 4% of vessels. Severe intimal dissection or inadequate hemodynamic result necessitated in adjunctive stenting in 20%. There were no incidents of vessel perforation or surgical target vessel revascularization. One patient (1.5%) died during the periprocedural period due to renal failure. After mean follow-up of 1 year (6-21 months), 89.5% of threatened limbs were salvaged. CBA is a safe and feasible option for the treatment of popliteal and infrapopliteal vessels.

Adult↗

PubMed2004

Predictors of vessel remodeling following directional coronary atherectomy.

The purpose of this study was to clarify predictors of vessel remodeling following directional coronary atherectomy (DCA). Negative remodeling after DCA leads to restenosis. However, little is known about the predictors of the vessel remodeling. Serial IVUS was performed in 43 lesions. The vessel remodeling was defined as adaptive if vessel area at follow-up minus postprocedure vessel area was > 0 mm2, or as constrictive if < 0 mm2. Adaptive remodeling occurred in 21 (49%) lesions. Postprocedure percent plaque area was smaller in the adaptive group (32.9% +/- 5.7% vs. 45.5% +/- 8.8%; P < 0.005). At follow-up, vessel area was larger in the adaptive group. However, plaque area was similar between the two groups. As a result, lumen area was larger in the adaptive group. Multivariate analyses showed that postprocedure percent plaque area < 40% was the only predictor of adaptive remodeling (odds ratio, 6.68; P < 0.05).

Adaptation, Physiological↗

PubMed1991

Effects of rotational atherectomy in normal canine coronary and diseased human cadaveric arteries: potential for plaque removal from distal, tortuous, and diffusely diseased vessels.

To test the hypothesis that tortuous, diseased vessels could be successfully treated with a flexible rotational atherectomy device we evaluated the BARD atherectomy device with quantitative angiography and histology in normal canine coronary arteries and diseased human below-knee amputation specimens. The mid left anterior descending and the circumflex vessels were treated in 4 dogs serially with 1 wk separating treatments. The acute and follow-up anterior descending artery size was unchanged (1.41 mm before, 1.39 mm after, and 1.59 mm at 1 week). Similar findings were obtained in the circumflex vessels. In 4 adult human amputated legs, diseased peroneal or tibial arteries were treated with a significant reduction in the percent luminal diameter stenosis from 62.75 prior to intervention to 36.5 following intervention (p = 0.021). The luminal diameter increased from 0.81 to 1.54 mm (p = 0.06). In 2 canine arteries there was histologic evidence of localized perforation of the arterial wall, but there was no angiographic evidence of perforation or dissection and no significant myocardial necrosis in the distribution of the treated vessels at 1 wk. The majority of the diseased human vessels demonstrated smoothly cut atheromas with sparing of the media. The rotational atherectomy catheter system holds promise for removal of plaque in relatively small, diffusely diseased, tortuous vessels.

Animals↗

PubMed1992

Monocyte diapedesis through an in vitro vessel wall construct: inhibition with monoclonal antibodies to thrombospondin.

Human peripheral blood monocytes were examined for migration across an endothelial cell monolayer in an in vitro vessel wall construct. Few monocytes invaded in the absence of a chemotactic gradient, despite significant adhesion to the endothelial monolayer. However, the addition of zymosan-activated human plasma to the lower compartment, to create a chemotactic gradient across the vessel wall, resulted in significantly enhanced monocyte migration. Pretreatment of the monocytes with monoclonal antibodies to thrombospondin (TSP) dramatically inhibited monocyte diapedesis into the vessel wall. The same treatment inhibited monocyte adhesion to endothelial cells in two-dimensional monolayer cultures as well as in vessel wall constructs (no chemotactic gradient). Of interest, however, the monoclonal antibodies had no inhibitory effect on monocyte migration into collagen gels devoid of endothelial cells in response to the same chemotactic gradient, suggesting the importance of TSP in monocyte-endothelial cell interactions. Monoclonal antibodies to fibronectin and normal mouse immunoglobulin G did not inhibit migration in this model of a vessel wall. Furthermore, monoclonal antibodies to TSP showed no inhibition of human peripheral blood neutrophil migration. Previous studies have shown that monocytes synthesize TSP and express this moiety on their surface. The present data suggest that monocytes may utilize TSP to interact with endothelial cells lining the vessel wall during diapedesis.

Antibodies, Monoclonal↗

PubMedDate not supplied

Vessel enhancement filtering in three-dimensional MR angiography.

For a variety of reasons, small vessels have low signal intensity in magnetic resonance angiography. When the vessel signal intensity is lower than the signal intensity of background tissues, these vessels tend not to be visible on maximum-intensity-projection images. The authors developed a nonlinear second-difference spatial filtering technique that enhances the details of small vessels while suppressing both noise and uniform background tissue. Two similar nonlinear second-difference filters are presented and compared with the linear Laplacian second-difference filter. To evaluate the performance of these filters, they were applied to intracranial three-dimensional time-of-flight MR angiographic data and the results compared with the vessel enhancement obtained with a simple second-difference Laplacian filter and with magnetization transfer contrast (MTC) techniques. The comparisons demonstrated that nonlinear filtering and MTC techniques result in similar improvement in small-vessel visibility and apparent continuity. A quantitative comparison demonstrated that the improvement in the contrast-to-noise ratio is much greater with the nonlinear filters than the Laplacian filter.

Circle of Willis↗

PubMedDate not supplied

Vessel enhancement filtering in three-dimensional MR angiography.

Circle of Willis↗

PubMed1982

Systematic error associated with apparatus 2 of the USP dissolution test II: Effects of deviations in vessel curvature from that of a sphere.

Dissolution vessels made from glass or plastic are recognized by the USP as being suitable for dissolution testing. Glass vessels with a bottom inside curvature flatter than that of a sphere can cause a high bias in dissolution results; vessels with a steeper curvature can cause a low bias. The inside bottom curvature of plastic vessels adhered closely to the curvature of a sphere. The plastic vessels are preferable for use if the drug is not adsorbed and the vessel is not attacked by the dissolution medium. Bias in results between individual positions of a dissolution apparatus was traced to two shafts which were not vertical.

Chemistry, Pharmaceutical↗

PubMed1987

Prognostic significance of lymph vessel involvement in gastric cancer.

We studied the prognostic significance of lymph vessel involvement in the gastric wall in 226 patients with advanced gastric cancer. There was no close correlation between the gross morphology of the cancer and the incidence of lymph vessel invasion. However, the more severe the degree of lymph vessel involvement, the higher was the incidence of lymph node metastasis. Severe lymph vessel invasion was found most frequently in poorly differentiated adenocarcinoma of the medullary type. Among patients with scirrhous carcinoma there were some in whom lymph vessel involvement was overlooked on routine histologic examination. Because the depth of lymph vessel invasion of the gastric wall was significantly related to the clinical course, we consider this to be of supplementary predictive value.

Carcinoma↗

PubMed2006

"Open y" technique in vessel diameter discrepancy.

For the last 20 years, free tissue transfers have increasingly become the mainstay of plastic surgery. Size discrepancy between the vessels during tissue transfers are frequently encountered in clinical practice, and this may potentially be an important factor in the patency of anastomosis. In our clinic, we first studied a rat model and a fresh sheep cadaver to improve the diameter discrepancy in microvascular anastomosis with "open y" technique. At the end of our research, we progressed to success, and the open y technique was applied to nine patients in our clinic with a diameter discrepancy in microvascular anastomosis. After finding the bifurcation of vessels (artery, vein, or a vein graft) that are prepared for anastomosis, a distal cut of 2-3 mm was made for the anastomosis, which is considered to increase the diameter. Both legs of the resultant "y"-shaped vessel were united after inserting the microscissors from one leg and exiting from the other. Performing an end-to-end anastomosis between the vessels, we obtain an increase in the diameter. By using this method, we eliminated the diameter discrepancy in microvascular anastomosis in nine patients in our clinic. There was not any flap loss. To increase the usage of this technique, when we come across a problem of size discrepancy, it is important to use the open y technique, both to the recipient vessels, donor vessels, and to the vein grafts. Owing to its high prevalence and the ease of application, we are convinced that this is a suitable technique in appropriate cases.

Anastomosis, Surgical↗

PubMed2005

Vessel size imaging in humans.

The relation of contrast-enhanced transverse relaxation rates R2* and R2 provides in vivo mapping of the mean caliber of cerebral vessels. This technique is referred to as vessel size imaging (VSI). Here a quantitative assessment of the vessel caliber in brain tumor patients is presented. The obtained mean vessel size shows sensitivity to the tumor type. A theoretical analysis is given to elucidate the morphological information content of VSI in the context of vessel architecture. The simplification of the theory underlying the data processing results in a systematic overestimation of the vessel caliber. An increase in the magnetic susceptibility of the contrast agent allows for quantitatively more accurate measurements. Quantitative VSI must include measurements of the regional diffusion coefficient and absolute determination of the regional cerebral blood volume.

Anisotropy↗

PubMed2004

The three-vessel and tracheal view of the fetal heart: an in utero sonographic evaluation.

OBJECTIVES: To establish a nomogram for fetal cardiac three-vessel view diameter changes during gestation. METHODS: The study is a prospective cross-sectional evaluation of 338 male and female fetuses between 14 and 38 weeks of normal singleton pregnancies. Measurements of fetal pulmonary artery, aorta and superior vena cava diameters, performed on a transverse view of the upper mediastinum were conducted using transvaginal ultrasonography between 14 to 18 weeks and transabdominal after 19 weeks' gestation. RESULTS: Adequate measurements of the three cardiac vessels were obtained in 338 fetuses. The regression equations for vessel diameters modeled as function of gestational age were pulmonary artery diameter (mm) = -2.275 + 0.273 x gestational age (week), aorta diameter (mm) = -1.77 + 0.227 x gestational age (week), and SVC diameter (mm) = -0.98 + 0.142 x gestational age (week). The correlation coefficients between gestational age and the diameter of the vessels were, r = 0.93, r = 0.93 and r = 0.86 for pulmonary artery, aorta and SVC respectively (all found to be highly statistically significant, p < 0.0001). The normal mean and 90% prediction limits were defined. CONCLUSION: Our data present the normal range of fetal heart three-vessel diameters during gestation. They may allow intrauterine assessment of their development and an adjunct in the detection and evaluation of great vessel pathology.

Aorta↗

PubMed1997

Leukotriene synthesis by isolated perinatal ovine intrapulmonary vessels correlates with age-related changes in 5-lipoxygenase protein.

Leukotrienes (LT) are potent vasoconstrictors in the pulmonary circulation. We have investigated the synthesis of LTC4 by intrapulmonary arteries and veins of perinatal lambs. Paired vessels of near-term fetal 146 +/- 2- and 2- to 7-day-old newborn lambs (each n = 7), were incubated for 10 min at 37 degrees C in baseline, with 1 mumol/L A32187 or 0.1 mmol/L arachidonic acid. Produced leukotriene C4 was assayed from media by ELISA. Baseline production of leukotriene (ng/mg tissue, means +/- SEM) by vessels for arteries was 0.006 +/- 0.001 and 0.059 +/- 0.009 for fetus and newborn, respectively. In veins, the values were 0.013 +/- 0.003 and 0.073 +/- 0.007 for fetus and newborn, respectively. On stimulation with the calcium ionophore A23187, production by arteries increased 25-fold in the fetus, but 4-fold in the newborn. The corresponding values for stimulated veins were 37-fold and 9-fold in fetus and newborn, respectively. Generally, production by veins was greater than production by the matching arteries. In all instances, the fetal vessels produced less leukotrienes than the newborn vessels. Western analysis of stimulated and unstimulated vessel membrane protein showed greater expression of 5-lipoxygenase in veins than in arteries (P < 0.05). Our data show that veins produce more LTC4 due to greater expression of 5-lipoxygenase in the vessels and thus suggest that veins of perinatal lamb lungs may be more susceptible to LT-induced vasoreactivity in the perinatal pulmonary circulation. We speculate that a higher production of LTC4 by fetal veins may be necessary to maintain a high venous tone in fetal lungs.

Age Factors↗