Mean Vessel Area Research Articles

Expeditious building of ring-porous earlywood vessel chronologies without loosing signal information

Chronologies of earlywood vessel size of ring- porous trees contain valuable ecological information, but long preparation procedures limit their application in eco- logical studies. Recent and fast techniques for wood surface preparation combined with automated image analysis are reducing the work needed to build chronolo- gies, but might also entail measurement inaccuracy. In this study, we aim to evaluate the effect of a possible effi- ciency-accuracy trade-off on ecological signal strength. To this end, we compare measurements of mean vessel area from two recent and fast procedures carried out on sanded wood surfaces with a reference procedure based on an accurate survey from thin sections. Measurements were performed on increment cores of 15 sessile oaks (Quercus petraea (Mattuschka) Liebl.) for the period 1956-2006. Dissimilarities in results with the reference procedure were quantified and evaluated. Our data show that the workload can be reduced by more than 20-fold when using the highly automated procedure. Signal weakening caused by mea- surement errors is negligible for vessels (6,000 lm 2 and can be easily compensated by increasing the sample size. Manual correction of misrecognized vessels hardly reduced this error further. The new procedures constitute a major step towards an efficient and accurate analysis of early- wood vessel chronologies of ring-porous tree species.

Wood anatomy and biometric parameters variation of Eucalyptus globulus clones

Variation in wood anatomy and biometric variables was studied in 14 7-year-old Eucalyptus globulus clones grown in a clonal trial in Arauco, Bio-Bio Region, Chile. Biometric characteristics were measured for each tree and the anatomical variables were measured at three radial positions by image analysis on transverse microsections cut from radial increment cores sampled at breast height. Results showed, that among clones wide ranges of variation were found for vessel frequency, vessel area and vessel coverage. However, narrow ranges of variation were found for fiber wall thickness, fiber diameter and lumen diameter. From pith to bark, mean vessel area and vessel coverage increased gradually, whereas the vessel frequency decreased. The fiber wall thickness did not differ significantly from pith to bark. Mean fiber and lumen diameters showed the same radial pattern, increasing from pith to the midpoint of the radius to reach a plateau close to the bark. Furthermore, important commercial volume gains that can exceed 100% were found. Considering the commercial importance of tree volume, vessel and fiber anatomy in the pulping and papermaking process, it is suggested that the information given in this study may be used as an additional criteria for the selection of E. globulus.

Effects of elevated CO2 and nitrogen on wood structure related to water transport in seedlings of two deciduous broad-leaved tree species

Wood structure might be altered through the physiological responses to atmospheric carbon dioxide concentration ([CO2]) and nitrogen (N) deposition. We investigated growth, water relations and wood structure of 1-year-old seedlings of two deciduous broad-leaved tree species, Quercus mongolica (oak, a ring-porous species) and Alnus hirsuta (alder, a diffuse-porous species and N2–fixer), grown under a factorial combination of two levels of [CO2] (36 and 72 Pa) and nitrogen supply (N; low and high) for 141 days in phytotron chambers. In oak, there was no significant effect of [CO2] on wood structure, although elevated [CO2] tended to decrease stomatal conductance (g s) and increased water use efficiency regardless of the N treatment. However, high N supply increased root biomass and induced wider earlywood and larger vessels in the secondary xylem in stems, leading to increased hydraulic conductance. In alder, there was significant interactive effect of [CO2] and N on vessel density, and high N supply increased the mean vessel area. Our results suggest that wood structures related to water transport were not markedly altered, although elevated [CO2] induced changes in physiological parameters such as g s and biomass allocation, and that N fertilization had more pronounced effects on non-N2-fixing oak than on N2-fixing alder.

A Comparison of Acquired Port-wine Stain with Congenital Port-wine Stain Using an Image Analyzer.

Recent reports have proposed that there were no differences between acquired port-wine stain (APWS) and congenital port-wine stain (CPWS) except the onset of disease. Pulsed dye laser (PDL) therapy is regarded as the treatment of choice in PWS. Although in some articles, APWS might have shown a better response to PDL than CPWS, this is still controversial. It has been assumed however, that there might be some differences determining therapeutic responses between the two entities. The purpose of this study is to find out some histopathologic differences between APWS and CPWS. 14 patients with APWS and 17 patients with CPWS from our patient files were included in this study. Immunohistochemical staining by factor VIII-related antigen was carried out on the specimens of punch biopsy to better visualize the blood vessels. Histopathologic assessment of variables such as vessel area, percentage of vascular area and vessel depth was performed using a computer-assisted image analyzer program. The mean vessel area in APWS was 1014.7 ± 782.5µm(2) and that of CPWS was 1341.5 ± 689.9µm(2). The mean percentage of vascular area in APWS was 2.02 ± 1.38% and that of CPWS was 2.65 ± 1.56%. The mean vessel depth in APWS was 327.5 ± 120.7µm and 321.7 ± 93.1µm in CPWS. No histopathologic variable was statistically significant using the Mann-Whitney test (p>0.05).

Angiogenesis Assessed in Tissue Microarrays of Diagnostic Follicular Lymphoma Correlates with Outcome.

Micro-vessel density (MVD) is a powerful prognostic factor in cancers but its value in haematological malignancies is more controversial. To examine its prognostic value in follicular lymphoma (FL) we assessed number and distribution of blood vessels by high-throughput tissue microarray and automated image analysis measurements in tissue microarrays (TMA) of paraffin-embedded, diagnostic lymph node biopsies taken from fifty-nine FL patients. These patients were selected from those who died from lymphoma progression less than 5 years after diagnosis (short survivor group) (n=34) and those who survived more than 15 years from diagnosis (long survivor group) (n=25). Immunohistochemistry was used in TMAs to study the number and location of vessels staining positive for the endothelial cell markers CD31 and CD34 and pericyte coverage using PDGFR. Interactive quantification using image analysis software was used to provide details of absolute numbers of vessels from each patient, as well as vessel size and their location. Image stacks of immunofluorescence stained sections were obtained using laser-scanning confocal microscopy to trace the tumour vasculature. Results demonstrated that both total vessel count and mean vessel area were significantly different between the two groups. Samples from the long survivor group were significantly more likely to have fewer (p=0.025), but larger vessels (p=0.002) than those from the short surviving group. The differences in vessel size and number were more prominent in inter-follicular vessels compared with those inside the neoplastic follicles. The smaller and more numerous blood vessels seen in the poorer prognostic sub-group likely reflects active, sprouting angiogenesis as confirmed by confocal microscopy. This study validates the use of TMAs to examine angiogenesis and demonstrates the powerful prognostic value of assessing MVD in FL. These results suggest that sprouting angiogenesis represents a therapeutic target in this disease and ongoing studies are investigating the mechanisms contributing to alteration in angiogenesis in different prognostic subgroups in FL and in transformation of this disease. The prognostic significance of MVD assessment in TMA is currently being evaluated in a validation set of FL samples.

Determinants of Lumen Loss Between Years 1 and 2 After Cardiac Transplantation

We previously reported that negative remodeling, not plaque progression, correlated with lumen loss during the first year after cardiac transplantation and that cytomegalovirus antibody seropositivity correlated with increased negative remodeling and greater lumen loss. Whether these findings persist between years 1 and 2 after transplantation is unknown. Serial 3-dimensional intravascular ultrasound analysis in the left anterior descending coronary artery was performed in 30 cardiac transplant recipients at year 1 and 2 after transplantation. Vessel, lumen, and plaque area were determined at 0.5-mm axial intervals in the first 50 mm of the left anterior descending coronary artery, and volumes were computed using Simpson's method. Univariate and multivariate regression analyses were performed to identify clinical predictors of change in coronary dimensions. Although mean vessel area did not change (13.6+/-3.4 to 13.4+/-3.3 mm/mm(3), P=0.45), mean plaque area increased (3.4+/-2.3 to 3.8+/-2.2 mm/mm(3), P=0.012), resulting in significant mean lumen area loss (10.3+/-2.5 to 9.6+/-2.3 mm/mm(3), P=0.016). However, the degree of luminal change strongly correlated with the degree of change in vessel size (R=0.81, P<0.0001), but not with change in plaque amount (R=-0.19, P=0.32). In fact, in 57% of the patients who demonstrated lumen loss, negative remodeling contributed more to lumen loss than did plaque progression. Diabetes at 2 years was the only significant independent clinical predictor of plaque progression and lumen loss. Despite significant plaque progression, negative remodeling correlated with coronary lumen loss between years 1 and 2 after cardiac transplantation.

Quantitative analysis of the microvasculature growing in the fibrin interface between a skin graft and the recipient site

Current tissue engineering techniques have failed to provide an established microvasculature in skin substitutes, a requisite for the maintenance of graft viability and rapid revascularization subsequent to graft transplantation in vivo. To improve outcomes for both conventional skin grafts and skin substitutes, the existing knowledge gap concerning the spatio-temporal mechanisms of skin graft revascularization must be abrogated. The current knowledge gap is due, at least in part, to a lack of appropriate diagnostic methods to quantify skin graft revascularization. To enhance the understanding of skin graft revascularization, we quantitatively evaluated revascularization of autologous skin grafts in a rat model by quantifying 2- and 3-dimensional vascular metrics in the fibrin interface 3, 7, and 10 days after transplantation. In this study, the fibrin interface appeared to be completely replaced with fibrovascular tissue by postoperative day 10. Although the mean vessel diameter was about 10 μm for the time points sampled, the mean vessel number, area, and volume fraction increased about 2.5-fold from postoperative day 3 to 7 and then decreased about 1.27-fold at postoperative day 10. There was no significant difference between 2- and 3-dimensional vascular metrics based on Bland–Altman analysis. In conclusion, these data establish a standard for metrics of vessels growing in the fibrin interface of a rat autologous skin graft and its donor site and suggests that once the blood supply has been restored to a viable transplant, the number, area, and volume fractions of vessels decrease to levels found at postoperative day 3.

Electromagnetic Breast Imaging: Results of a Pilot Study in Women with Abnormal Mammograms

To prospectively assess quantitatively the inherent contrast of electromagnetic (EM) properties that can be imaged by using available technology in women with abnormal findings at conventional breast imaging who underwent subsequent biopsy. The protocol was HIPAA compliant and approved by the institutional review board. All participants provided informed consent. Fifty-three women with normal (Breast Imaging Reporting and Data System [BI-RADS] category 1) and ninety-seven women with abnormal (BI-RADS category 4 or 5) screening mammograms were imaged with three EM imaging methods: electrical impedance spectroscopy (EIS), microwave imaging spectroscopy (MIS), and near-infrared spectral tomography (NIR). A region-of-interest (ROI) analysis was used to assess the EM image properties for comparison of findings with conventional image findings and correlation with specific pathologic parameters for women with abnormal findings. Statistical analyses were conducted. One hundred fifty participants (age range, 35-81 years) were included. EM image property contrast ratios of 150%-200% were found in breast abnormality ROIs relative to the ipsilateral breast background. Analysis of variance demonstrated significant differences in ROI image summaries of mammographically normal versus abnormal breasts for EIS, across diagnostic groups for NIR, and for MIS (analysis restricted to lesions larger than 1 cm(3)). Receiver operating curve (ROC) analysis of the EM properties for cancers among subjects with BI-RADS category 4 or 5, compared with the EM properties for the subjects with normal breasts (BI-RADS category 1), yielded areas under the ROC curve ranging from 0.67 to 0.81. Pathologic correlations with mean vessel density, mean vessel area, and epithelium-to-stroma ratio suggest a biological origin of the EM image properties associated with disease. Results from EM breast examinations provide statistical evidence of a mean increase in image contrast of 150%-200% between abnormal (benign and malignant) and normal breast tissue.

Temperature responses of growth and wood anatomy in European beech saplings grown in different carbon dioxide concentrations

Effects of temperature on growth and wood anatomy were studied in young European beech (Fagus sylvatica L.) grown in 7-l pots for 2.5 years in field-phytotron chambers supplied with an ambient (approximately 400 micromol mol-1) or elevated (approximately 700 micromol mol-1) carbon dioxide concentration ([CO2]). Temperatures in the chambers ranged in increments of 2 degrees C from -4 degrees C to +4 degrees C relative to the long-term mean monthly (day and night) air temperature in Berlin-Dahlem. Soil was not fertilized and soil water and air humidity were kept constant. Data were evaluated by regression analysis. At final harvest, stem diameter was significantly greater at increased temperature (Delta1 degrees C: 2.4%), stems were taller (Delta1 degrees C: 8.5%) and stem mass tree-1 (Delta1 degrees C: 10.9%) and leaf area tree-1(Delta1 degrees C: 6.5%) were greater. Allocation pattern was slightly influenced by temperature: leaf mass ratio and leaf area ratio decreased with increasing temperature (Delta1 degrees C: 2.3% and 2.2% respectively), whereas stem mass/total mass increased (Delta1 degrees C: 2.1%). Elevated [CO2] enhanced height growth by 8.8% and decreased coarse root mass/total mass by 10.3% and root/shoot ratio by 11.7%. Additional carbon was mainly invested in aboveground growth. At final harvest a synergistic interaction between elevated [CO2] and temperature yielded trees that were 3.2% taller at -4 degrees C and 12.7% taller at +4 degrees C than trees in ambient [CO2]. After 2.5 seasons, cross-sectional area of the oldest stem part was approximately 32% greater in the +4 degrees C treatment than in the -4 degrees C treatment, and in the last year approximately 67% more leaf area/unit tree ring area was produced in the highest temperature regime compared with the lowest. Elevated [CO2] decreased mean vessel area of the 120 largest vessels per mm2 by 5.8%, causing a decrease in water conducting capacity. There was a positive interaction between temperature and elevated [CO2] for relative vessel area, which was approximately 38% higher at +4 degrees C than at -4 degrees C in elevated [CO2] compared with ambient [CO2]. Overall, temperature had a greater effect on growth than [CO2], but elevated [CO2] caused quantitative changes in wood anatomy.

Effect of Atherosclerotic Regression on Total Luminal Size of Coronary Arteries as Determined by Intravascular Ultrasound

We assessed vascular changes during atherosclerosis regression. Compensatory enlargement of coronary arteries accommodates plaque burden during atherosclerosis development. Lipid-lowering therapy has altered the natural history of coronary atherosclerosis, but the arterial changes that occur during disease regression need to be clarified. Intravascular ultrasound was performed at baseline and after approximately 18 months in 432 patients with coronary disease. Mean plaque, lumen, and total vessel area were computed in a 30-mm coronary segment of interest. Mean low-density lipoprotein cholesterol level was 2.4 mmol/L, and 88% of patients received statins. Overall, changes in plaque and total vessel areas were highly correlated (r = 0.82, p <0.0001). Among the 227 patients with plaque regression, the plaque area decrease was -0.58 +/- 0.54 mm(2), and changes in total vessel and lumen areas were -1.02 +/- 1.10 and -0.44 +/- 0.86 mm(2), respectively. The decrease in plaque area correlated better with the change in total vessel area (r = 0.64, p <0.0001) than with the change in lumen area (r = 0.20, p = 0.003). The relation between plaque regression and decrease in total vessel area was significantly better (p = 0.019) for patients with a >40% atheroma area (r = 0.72; p <0.0001) than for those with <or=40% (r = 0.48; p = 0.0004). In conclusion, regression of atherosclerotic plaque is generally accompanied by a decrease in total vessel size, without an increase in luminal dimensions. This reverse vascular remodeling may be responsible for the "regression paradox," whereby secondary prevention is associated with clinical benefits despite minimal improvement in coronary lumen dimensions.

Mycophenolate Mofetil Reduces Intimal Thickness by Intravascular Ultrasound After Heart Transplant: Reanalysis of the Multicenter Trial

The mycophenolate mofetil (MMF) trial involved 650 heart transplant patients from 28 centers who received MMF or azathioprine (AZA), both in combination with cyclosporine and corticosteroids. Baseline and 1-year intravascular ultrasound (IVUS) were performed in 196 patients (102 MMF and 94 AZA) with no differences between groups in IVUS results analyzed by morphometric analysis (average of 10 evenly spaced sites, without matching sites between studies). Baseline to first-year IVUS data can also be analyzed by site-to-site analysis (matching sites between studies), which has been reported to be more clinically relevant. Therefore, we used site-to-site analysis to reanalyze the multicenter MMF IVUS data. IVUS images were reviewed and interpretable in 190 patients (99 MMF and 91 AZA) from the multicenter randomized trial. The AZA group compared to the MMF group had a larger number of patients with first-year maximal intimal thickness (MIT)>or=0.3 mm (43% vs. 23%, p=0.005), a greater decrease in the mean lumen area (p=0.02) and a decrease in the mean vessel area (the area actually increased in the MMF group, p=0.03). MMF-treated heart transplant patients compared to AZA-treated patients, both concurrently on cyclosporine and corticosteroids, in this study have significantly less progression of first-year intimal thickening.

Coronary Endothelial Vasomotor Function and Vascular Remodeling in Heart Transplant Recipients Randomized for Tacrolimus or Cyclosporine Immunosuppression

This study aimed to compare changes in coronary endothelial function, systemic endothelin-1 (ET-1) levels, and vascular remodeling in heart transplant recipients randomized to cyclosporin A (CyA) or tacrolimus (Tac) immunosuppression. Functional endothelial abnormalities and intimal thickening are sensitive measures of early cardiac allograft vasculopathy (CAV). The randomized, prospective study was performed in two groups of 22 patients, maintained on Tac or CyA and mycophenolate mofetil immunosuppression, 1 and 12 months after heart transplantation. We investigated epicardial luminal diameter, coronary blood flow velocity, and ET-1 plasma levels at 1 and 12 months after transplantation. Structural coronary alterations were determined using intravascular ultrasound. Epicardial vasomotor function at baseline and during follow-up was comparable between the groups. Deterioration of microvascular endothelial function during follow-up was significantly enhanced in the CyA versus Tac group (p < 0.05). Circulating ET-1 concentration increased in the CyA group but significantly decreased over time in the Tac group (CyA +17% vs. Tac -25%; p < 0.05). The time-dependent increase in mean intimal area was significantly enhanced in the CyA versus Tac group, whereas the vessel area significantly increased during follow-up in the Tac compared with the CyA group. Epicardial endothelial function is comparable between CyA- and Tac-treated patients. Microvascular endothelial function deteriorates more in CyA-treated patients, a finding that correlates with enhanced ET-1 concentration and an increased intimal area during follow-up. The mean vessel area in the Tac group increased over time, indicating positive vascular remodeling. Tac is superior to CyA with respect to microvascular endothelial function, intimal thickening, and vascular remodeling.

Endometrial vascularization in levonorgestrel intrauterine device users; computerized microvessel measurement study

Levonorgestrel use in the levonorgestrel intrauterine device (LNG-IUS) induces vascular distension within the superficial layer of the endometrium and massive pseudodecidualization. With a computer-assisted image analysis system, we objectively measured the vascular bed in LNG-IUS users and compared it to the physiological endometrium. A study was undertaken on 25 women using LNG-IUS, in an outpatient procedure at the time of removal of the IUS and compared with 11 normally cycling women (control group). Suction curette specimens were obtained just after retrieval of the IUS, and immunohistochemistry was carried out with a specific marker of the endothelial cells (CD31). Number of vessels decreased in the LNG-IUS group to 60/mm 2 versus 124/mm 2 in the control group, and mean vessel area increased to 1255 μm 2 versus 157 μm 2, respectively, in the control group. The decrease in mean vascular density and the increase of mean vessel area in the LNG-IUS group, compared to the control group, were both highly significant (p<.001).

Impact of different progestins on endometrial vascularisation of postmenopausal women. A retrospective image analysis—morphometric study

Objectives: To determine if the vascularisation of the endometrium is dependent on the administered progestin during sequential hormone replacement therapy . Methods: Nine women received percutaneous estradiol-17β, 1.5 mg/day from days 1 to 24 combined with 200 mg/day micronised progesterone from days 11 to 24 of the treatment cycle. Fifteen women received percutaneous estradiol, 1.5 mg/day from days 1 to 24, combined with 10 mg/day chlormadinone acetate from days 11 to 24. Eleven women received percutaneous estradiol, 50 μg/day from days 1 to 28 combined with percutaneous norethisterone acetate, 0.3mg/day form days 14 to 28. Twelve women received intranasal estradiol, 300 μg/day from days 1 to 25 combined with 0.5 mg of promegestone from days 11 to 24. Eleven spontaneous cycling women had an endometrial biopsy during luteal phase and served as controls. Endometrial biopsies were processed routinely between days 18 and 24 and sections were immunostained using anti-CD34 antibody to identify vascular endothelial cells, which were treated with an automatic image analysis system. Results: mean (±S.D.) vascular density for controls was 147±41.5 vessels/mm 2, with mean vessel area of 143±60.9 μm 2. In chlormadinone users endometrial microvascular density and mean vessel area did not differ from the control group (150.2±58.6 and 152.9±70.5). The other three progestins generated a significant increase of mean vessel density, 179.6±51.6 with micronised progesterone, 178.5±67.6 with norethisterone and 179.6±48.4 with promegestone. The mean vessel area was lower in the latter three groups, respectively, 108.4±39.0, 97.5±46.5 and 141.6±66.7 μm 2, promegestone leading to non significant difference with control. Conclusion: regarding vascularisation, chlormadinone and control group gave similar patterns. Promegestone was associated with an increase of the number of vessels, as did micronised progesterone or norethisterone; the mean vascular area was the smallest in the norethisterone group.

Relative contributions of intimal hyperplasia and vascular remodeling in early cardiac transplant-mediated coronary artery disease

The relative contribution of intimal hyperplasia and vascular remodeling in early transplant coronary artery disease (TxCAD) is unknown. This study was designed to determine the contributions of vascular remodeling and intimal hyperplasia in the initial year after transplantation by intravascular ultrasound (IVUS). Twenty-five patients underwent baseline (<6 weeks after transplant) and 1-year angiography and IVUS to evaluate total vessel, luminal, and intimal + medial areas in ≥3 segments of the coronary artery. Nine patients had donor atherosclerotic disease on baseline study (23% of segments), and at 1-year, 21 patients (84%) had intimal hyperplasia (70% of segments). Fourteen patients had positive remodeling in all arterial segments, whereas the remaining 11 had positive and negative remodeling in the same vessel. Mean plaque area and total vessel area increased significantly (p = 0.0001) in proximal, mid, and distal segments, whereas total vessel area was most pronounced in distal segments. Luminal area did not change over time. Of the 87 segments evaluated, 68 (78%) had an increase in total vessel area, 57 (66%) had intimal growth, and 54 (62%) had an increase in luminal area. Although changes in total vessel and luminal area were closely correlated, a decrease in luminal area was associated with positive and negative remodeling. In conclusion, luminal area is generally maintained during the initial transplant year despite significant intimal hyperplasia due to positive remodeling. Reduction in the luminal area results from either inadequate positive remodeling or negative remodeling without intimal growth and often occurs in the same artery.

Diffuse intimal thickening of coronary arteries in slow coronary flow.

Intravascular ultrasound imaging can detect intimal thickening and is suitable for detection of early atherosclerosis, which cannot be detected by conventional angiography. The aim of the present study was to investigate the epicardial coronary morphology and intracoronary pressure in relation to slow coronary flow (SCF). The study population consisted of 19 patients with SCF [11 (57.9%) females; 55.95 +/- 9.42 years]. Proximal, middle, distal and mean total vessel area, lumen area, intima + media area (IMA), percent IMA, and maximal intima + media (I + M) thickness were calculated and compared to healthy subjects. Proximal, middle, distal and mean I + M thickness, IMA, and % IMA of patients with SCF were found to be significantly higher than those of control subjects. Longitudinally extended massive calcification throughout the epicardial arteries was found in 13 (68.49%) patients with SCF and regional calcification was found in 6 (31.6%) patients with SCF. Proximal and distal pressure gradients of patients with SCF were determined to be 15.84 +/- 12.11 mmHg in the intracoronary pressure measurements. Fractional flow reserve values were significantly lower than the normal population (0.83 +/- 0.13, P < 0.0001). This study indicates that patients with SCF have diffuse intimal thickening, widespread calcification along the vessel wall and atheroma which does not cause luminal irregularities in coronary angiography, and a pressure gradient between proximal and distal segments of epicardial coronary arteries with SCF. Based on these results, we believe that SCF may be a form of diffuse atherosclerosis involving both the microvascular system and epicardial coronary arteries.

CLONAL AND SITE VARIATION OF VESSELS IN 7-YEAR-OLD EUCALYPTUS GLOBULUS

Pith to bark variation of vessel anatomy was studied in 17 clones of 7-year-old Eucalyptus globulus trees grown on two sites in Portugal. Vessels were measured by image analysis on transverse microsections cut from radial strips sampled at 25% tree height. The mean vessel area increased gradually from pith to bark, whereas the vessel frequency (number of vessels per unit area) decreased outwards from the innermost ring on and levelled off towards the bark. The proportion of vessels relative to other tissues remained constant across the radius. The vessel variables showed cyclic variations defined by minima (vessel area and proportion) or maxima (number of vessels). The effect of site and clone on vessel variability was significant. Clonal variation accounted for 30% and site explained 67% of the total variance of vessel proportion. At the least water stressed site, vessels appeared to be generally larger and occupied a greater proportion of total cross-sectional area.

Tumor angiogenesis as a prognostic factor in thick cutaneous malignant melanoma. A quantitative morphologic analysis.

The prognostic value of the extent of neovascularization in cutaneous melanoma is a highly controversial issue. The aim of the current study was to evaluate whether the morphometric analysis of tumor vascularity may be helpful in predicting the clinical outcome of patients with thick cutaneous melanomas. A series of 15 patients with melanoma (>3 mm in thickness) who did not experience disease progression after long-term follow-up (10 years) and 30 matched controls who underwent recurrence and/or metastases were selected for the study. Microvessels were immunohistochemically stained with anti-CD31 antibody. Several parameters, including vessel number, vascular density, vessel area, equivalent circle diameter, perimeter, shape factor, compactness, and the number of vascular ramifications per 100 vessel sections, were quantitatively assessed by a computer-aided semi-automatic image analysis system. Mean vessel area was 341.69 microm2 in cases without progression and 512.55 microm2 in the progressed melanomas (P=0.008, Mann-Whitney U test). The mean equivalent circle diameter was 18.95 microm in non-progressed melanomas and 22.57 microm in progressed melanomas (P=0.009). The mean number of ramifications was 0.8 in cases without progression and 1.9 in the controls (P=0.03). Microvessel count and vascular density were higher in progressed cases (17.37 vs. 11.73 and 28.94/mm2 vs. 19.55/mm2, respectively), but the difference did not reach statistical significance (P=0.06). Our results suggest that neovascularization is a critical event in the progression of thick melanoma. Its prognostic significance is better assessed by quantification of vessel area, equivalent circle diameter, and microvessel branching, whereas microvessel count and vascular density do not provide significant prognostic information.

Vascular endothelial growth factor (VEGF) expression in the subacromial bursa is increased in patients with impingement syndrome

Vascular endothelial growth factor (VEGF), which is known to be an angiogenetic factor, plays an important role in the inflammation of synovial tissue. To investigate the relationships between VEGF and clinical symptoms in rotator cuff disease, VEGF expression was examined using RT–PCR and immunohistochemical analysis in 50 patients with this disease (26 with full-thickness cuff tear, 12 with partial-thickness tear, and 12 with subacromial bursitis). VEGF mRNA expression was detected in 40 out of 50 patients by RT–PCR. VEGF mRNA expression was found more frequently in the patients with motion pain (39 out of 41) than in those without motion pain (1 out of 9) with statistical significance (Fisher's test, P<0.001). Thirty-one out of 33 patients with synovial proliferation showed VEGF mRNA expression, whereas the expression of this transcript was found in 9 out of 17 patients without synovial proliferation. This association with synovial proliferation was also significant (Fisher's test, P=0.0013). Thirty out of 41 patients with motion pain had synovial proliferation but 3 out of 9 patients without motion pain had synovial proliferation. In all these 30 patients with both motion pain and synovial proliferation, VEGF mRNA expression was detected. This association between motion pain and synovial proliferation was also significant (Fisher's test, P<0.05). The mean vessel count and area in subacromial bursa expressing VEGF was significantly higher than in those without VEGF (Mann–Whitney's U test, P<0.01). These results suggested that VEGF expression is associated with vascularity, synovial proliferation and shoulder motion pain in the rotator cuff disease.

Coronary artery disease: arterial remodelling and clinical presentation

OBJECTIVETo investigate the hypothesis that in coronary artery disease large plaques in compensatorily enlarged segments are associated with acute coronary syndromes, whereas smaller plaques in shrunken segments are associated with...