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T J Anderson

Publications and source records attributed to T J Anderson.

At least 73 records · Page 4Linked to original sources

Suppression of displacement in severely slowed saccades.

Severely slowed saccades in Spinocerebellar ataxia have previously been shown to be at least partially closed-loop in nature, their long duration means that they can be modified in-flight in response to intrasaccadic target movements. In this study, a woman with these pathologically slowed saccades could modify them in-flight in response to target movements, even when saccadic suppression of displacement (SSD) prevented conscious awareness of those movements. Thus, SSD is not complete, in that it provides perceptual information that is sub-threshold to consciousness but which can still be effectively utilised by the oculomotor system.

Adolescent↗

Comparative study of ACE-inhibition, angiotensin II antagonism, and calcium channel blockade on flow-mediated vasodilation in patients with coronary disease (BANFF study)

OBJECTIVES: To determine the effect of angiotensin-converting enzyme (ACE) inhibition on brachial flow-mediated vasodilation. BACKGROUND: Quinapril, an ACE inhibitor with high affinity, has been shown to improve coronary endothelial dysfunction in patients with coronary artery disease. The effectiveness of different vasoactive agents to improve human endothelial function is unknown. METHODS: High resolution ultrasound was used to assess endothelium-dependent brachial artery flow-mediated vasodilation (FMD) in patients with coronary disease. We studied 80 patients (mean age 58 +/- 0.9 years) in a partial-block, cross-over design trial. Patients were randomized to one of four different drug sequences to receive quinapril 20 mg, enalapril 10 mg, losartan 50 mg or amlodipine 5 mg daily. Each patient received three drugs with a two-week washout period between treatments. The primary end point was the absolute difference in FMD after eight weeks of each study drug compared with their respective baselines analyzed in a blinded fashion. RESULTS: There was mild impairment of FMD at baseline (7.3 +/- 0.6%). The change in FMD from baseline was significant only for quinapril (1.8 +/- 1%, p < 0.02). No change was seen with losartan (0.8 +/- 1.1%, p = 0.57), amlodipine (0.3 +/- 0.9%, p = 0.97) or enalapril (-0.2 +/- 0.8%, p = 0.84). No significant change in nitroglycerin-induced dilation occurred with drug therapy. The improvement in quinapril response was not seen in those with the DD ACE genotype (0.5 +/- 2.1%) but was seen in those with the ID and II genotype (3.3 +/- 1.2 and 3.2 +/- 1.9%, respectively, p = 0.03). CONCLUSION: Only quinapril was associated with significant improvement in FMD, and this response is related to the presence of the insertion allele of the ACE genotype.

Aged↗

Effective tamoxifen therapy of breast cancer involves both antiproliferative and pro-apoptotic changes.

Despite knowledge of oestrogen receptor status, it is not always possible to predict which breast cancers will respond to tamoxifen. We have previously reported that decreased expression of Bcl-2 and/or Ki-S1 were associated with tumour response to neo-adjuvant tamoxifen in 50 elderly women with oestrogen receptor (ER)-positive breast cancer. In this study, we confirm that the expression of Bcl-2 and Ki-S1 are surrogates for the frequency of apoptosis and mitosis respectively, within these untreated breast cancers, with an inverse relationship between Bcl-2 expression and the apoptotic index (P<0.05), and a positive relationship between Ki-S1 expression and the mitotic index (P<0.01). However, after 3 months' tamoxifen treatment these relationships were no longer apparent. Moreover, amongst the 27 tumours in which Bcl-2 expression was reduced during the 3 months' therapy, there was a significant correlation between the response to therapy and the increase in apoptosis (P<0.05), whereas in those tumours in which Bcl-2 did not fall with therapy, there was a significant correlation between response and the decrease in mitosis (P<0.05). These data suggest there are at least two mechanisms for effective tamoxifen therapy: increased apoptosis as a consequence of reduced Bcl-2 expression, and decreased proliferation.

Aged↗

Do malaria parasites mate non-randomly in the mosquito midgut?

Polymerase chain reaction (PCR)-based genotyping of oocysts dissected from mosquito midguts has previously been used to investigate overall levels of inbreeding within malaria parasite populations. We present a re-analysis of the population structure of Plasmodium falciparum malaria using diploid genotypes at three antigen-encoding loci in 118 oocysts dissected from 34 mosquitoes. We use these data to ask whether mating is occurring at random within the mosquito midgut, as is generally assumed. We observe a highly significant deficit of heterozygous oocysts within mosquitoes at all three loci, suggesting that fusion of gametes occurs non-randomly in the mosquito gut. A variety of biological explanations, such as interrupted feeding of mosquitoes, positive assortative mating and outcrossing depression, could account for this observation. However, an alternative artefactual explanation--the presence of non-amplifying or null alleles--can account for the observed data equally well, without the need to invoke non-random mating. To evaluate this explanation further, we estimate the frequencies of null alleles within the oocyst population using maximum likelihood, by making the assumption that non-amplifying oocysts at any of the three loci are homozygous for null alleles. Observed levels of visible heterozygotes fit closely with those expected under random mating when non-amplifying oocysts are accounted for. Other lines of evidence also support the artefactual explanation. Overall inbreeding coefficients have been recalculated in the light of this analysis, and may be considerably lower than those estimated previously. In conclusion, we suggest that the deficit of heterozygotes observed is unlikely to indicate non-random mating within the mosquito gut and is better explained by misscoring of heterozygotes as homozygotes.

Alleles↗

Complex mutations in a high proportion of microsatellite loci from the protozoan parasite Plasmodium falciparum.

Microsatellite loci are generally assumed to evolve via a stepwise mutational process and a battery of statistical techniques has been developed in recent years based on this or related mutation models. It is therefore important to investigate the appropriateness of these models in a wide variety of taxa. We used two approaches to examine mutation patterns in the malaria parasite Plasmodium falciparum: (i) we examined sequence variation at 12 tri-nucleotide repeat loci; and (ii) we analysed patterns of repeat structure and heterozygosity at 114 loci using data from 12 laboratory parasite lines. The sequencing study revealed complex patterns of mutation in five of the 12 loci studied. Alleles at two loci contain indels of 24 bp and 57 bp in flanking regions, while in the other three loci, blocks of imperfect microsatellites appear to be duplicated or inserted; these loci essentially consist of minisatellite repeats, with each repeat unit containing four to eight microsatellites. The survey of heterozygosity revealed a positive relationship between repeat number and microsatellite variability for both di- and trinucleotides, indicating a higher mutation rate in loci with longer repeat arrays. Comparisons of levels of variation in different repeat types indicate that the mutation rate of dinucleotide-bearing loci is 1.6-2.1 times faster than trinucleotides, consistent with the lower mean number of repeats in trinucleotide-bearing loci. However, despite the evidence that microsatellite arrays themselves are evolving in a manner consistent with stepwise mutation model in P. falciparum, the high frequency of complex mutations precludes the use of analytical tools based on this mutation model for many microsatellite-bearing loci in this protozoan. The results call into question the generality of models based on stepwise mutation for analysing microsatellite data, but also demonstrate the ease with which loci that violate model assumptions can be detected using minimal sequencing effort.

Animals↗

Pathology characteristics that optimize outcome prediction of a breast screening trial.

The ability of pathology characteristics to predict outcome was tested with the 1029 cancers accumulated in the Edinburgh Randomized Trial of breast screening after 14 years follow-up. The majority (55.7%) were in the screening arm, which also had more operable cases (81.3% vs 62.2%); the reduction in the proportion of inoperable breast cancers in a UK female population invited to mammographic screening is a notable effect of the trial. In the 691 operable invasive cases the size, histological type, grade, node status and node number group individually showed highly significant (P<0.001) association with survival. In multivariate analysis the Nottingham Prognostic Index (NPI) derived from these features showed highly significant association with survival (P<0.001). However, when first adjusted for NPI, combined addition of pathological size in 6 categories and histological type as special or not had an independent association with survival that was statistically firmly based (P<0.001). For operable breast cancer the gains are in smaller sizes, better histological features, and higher proportion node negative. The weighting factors applied to pathology indicators of survival in the NPI are not optimal for a population included in a trial of screening. In particular, a linear trend of the index with pathological size is not appropriate. Inclusion of histological type as special or not improves the index further.

Analysis of Variance↗

Tetrahydrobiopterin improves endothelial function in human saphenous veins.

OBJECTIVES: Diminished production of nitric oxide has been linked to saphenous vein endothelial dysfunction. Tetrahydrobiopterin is an obligate cofactor for the oxidation of L -arginine by nitric oxide synthase in the production of nitric oxide by endothelial cells. The objective of the present study was to examine whether the exogenous addition of tetrahydrobiopterin improves endothelial function in saphenous veins from patients undergoing coronary artery bypass graft operations. METHODS: Vascular segments of saphenous veins were obtained from 17 patients undergoing elective coronary artery bypass grafting, and in vitro endothelium-dependent and endothelium-independent responses to acetylcholine and sodium nitroprusside were assessed. Isometric dose-response curves were constructed in precontracted rings in the presence and absence of tetrahydrobiopterin (0.1 mmol/L) with the use of the organ bath apparatus. The percentages of maximum relaxation and sensitivity were compared between interventions. RESULTS: Acetylcholine caused dose-dependent endothelium-mediated relaxation in saphenous veins. In the presence of tetrahydrobiopterin, acetylcholine-induced relaxation was significantly augmented (percentage maximum relaxation, 16.8% +/- 2.9% vs control 7.5% +/- 1.8%; P =.003) without an effect on agonist sensitivity. These effects were endothelium-specific because endothelium-independent responses to sodium nitroprusside were preserved. CONCLUSIONS: These data uncover beneficial effects of acute tetrahydrobiopterin addition on endothelial function in human vessels. Because endothelial dysfunction has been implicated in the development of graft failure, studies aimed at chronic delivery of tetrahydrobiopterin would be useful in determining the contribution of this cofactor toward saphenous vein atherosclerosis.

Acetylcholine↗

Microsatellite markers reveal a spectrum of population structures in the malaria parasite Plasmodium falciparum.

Multilocus genotyping of microbial pathogens has revealed a range of population structures, with some bacteria showing extensive recombination and others showing almost complete clonality. The population structure of the protozoan parasite Plasmodium falciparum has been harder to evaluate, since most studies have used a limited number of antigen-encoding loci that are known to be under strong selection. We describe length variation at 12 microsatellite loci in 465 infections collected from 9 locations worldwide. These data reveal dramatic differences in parasite population structure in different locations. Strong linkage disequilibrium (LD) was observed in six of nine populations. Significant LD occurred in all locations with prevalence <1% and in only two of five of the populations from regions with higher transmission intensities. Where present, LD results largely from the presence of identical multilocus genotypes within populations, suggesting high levels of self-fertilization in populations with low levels of transmission. We also observed dramatic variation in diversity and geographical differentiation in different regions. Mean heterozygosities in South American countries (0.3-0.4) were less than half those observed in African locations (0. 76-0.8), with intermediate heterozygosities in the Southeast Asia/Pacific samples (0.51-0.65). Furthermore, variation was distributed among locations in South America (F:(ST) = 0.364) and within locations in Africa (F:(ST) = 0.007). The intraspecific patterns of diversity and genetic differentiation observed in P. falciparum are strikingly similar to those seen in interspecific comparisons of plants and animals with differing levels of outcrossing, suggesting that similar processes may be involved. The differences observed may also reflect the recent colonization of non-African populations from an African source, and the relative influences of epidemiology and population history are difficult to disentangle. These data reveal a range of population structures within a single pathogen species and suggest intimate links between patterns of epidemiology and genetic structure in this organism.

Africa↗

Inhibition of adhesion of Escherichia coli k88ac fimbria to its receptor, intestinal mucin-type glycoproteins, by a monoclonal antibody directed against a variable domain of the fimbria.

Strains of enterotoxigenic Escherichia coli that express K88 fimbriae are among the most common causes of diarrhea in young pigs. Adhesion of bacteria to receptors on intestinal epithelial cells, mediated by K88 fimbriae, is the initial step in the establishment of infection. Three antigenic variants of K88 fimbriae exist in nature: K88ab, K88ac, and K88ad. K88ac is the most prevalent and may be the only variant of significance in swine disease. Each K88 fimbrial variant is composed of multiple antigenic determinants. Some of these determinants are shared among the three variants and may be referred to as conserved epitopes, whereas others are unique to a specific variant and may be referred to as variable epitopes. In this study, monoclonal antibodies (MAbs) specific to either variable or conserved epitopes of K88ac fimbriae were produced. The specificity of each MAb was tested by enzyme-linked immunosorbent and immunoblot assays. Fab fragments were prepared from these MAbs and were tested for their ability to block the binding of K88-positive bacteria and purified fimbriae to porcine enterocyte brush border vesicles and purified K88 receptors, respectively. The purified receptors were intestinal mucin-type sialoglycoproteins (IMTGP) isolated from porcine enterocytes (A. K. Erickson, D. R. Baker, B. T. Bosworth, T. A. Casey, D. A. Benfield, and D. H. Francis, Infect. Immun. 62:5404-5410, 1994). Fab fragments prepared from MAbs specific for variable epitopes blocked the binding of bacteria to brush borders and of fimbriae to IMTGP. However, those from MAbs specific for a conserved epitope did not. These observations indicate that the receptor-binding domain of a K88ac fimbria is contained, at least in part, within the antigenically variable epitopes of that fimbria. Epitope mapping for one of the MAbs, which recognizes a linear epitope on K88ac fimbriae, indicated that this MAb binds to the region from amino acid no. 64 to no. 107 on the major subunit of K88ac fimbriae.

Adhesins, Escherichia coli↗

Wave-intensity analysis: a new approach to coronary hemodynamics.

In 10 anesthetized dogs, we measured high-fidelity left circumflex coronary (P(LCx)), aortic (P(Ao)), and left ventricular (P(LV)) pressures and left circumflex velocity (U(LCx); Doppler) and used wave-intensity analysis (WIA) to identify the determinants of P(LCx) and U(LCx). Dogs were paced from the right atrium (control 1) or right ventricle by use of single (control 2) and then paired pacing to evaluate the effects of left ventricular contraction on P(LCx) and U(LCx). During left ventricular isovolumic contraction, P(LCx) exceeded P(Ao), paired pacing increasing the difference. Paired pacing increased DeltaP(X) (the P(LCx)-P(Ao) difference at the P(Ao)-P(LV) crossover) and average dP(LCx)/dt (P < 0.0001 for both). During this time, WIA identified a backward-going compression wave (BCW) that increased P(LCx) and decreased U(LCx); the BCW increased during paired pacing (P < 0.0001). After the aortic valve opened, the increase in P(Ao) caused a forward-going compression wave that, when it exceeded the BCW, caused U(LCx) to increase, despite P(LV) and (presumably) elastance continuing to increase. Thus WIA identifies the contributions of upstream (aortic) and downstream (microcirculatory) effects on P(LCx) and U(LCx).

Animals↗

Normal endothelial function despite insulin resistance in healthy women with the polycystic ovary syndrome.

Women with the polycystic ovarian syndrome (PCOS) carry a number of cardiovascular risk factors, including insulin resistance, lipid abnormalities, and an altered pattern of sex steroid exposure. Noninvasive measurements of endothelial function, which can demonstrate abnormalities well in advance of clinically apparent disease, have not been previously reported in this patient group. We undertook a cross-sectional evaluation of endothelium-dependent and -independent vascular function using brachial artery ultrasound. We studied healthy women with clinical and laboratory evidence of PCOS (n = 18) and age-matched controls (n = 19), not taking any antihypertensive, cholesterol-lowering, or hormonal therapies. Laboratory parameters of insulin resistance, glycemia, cholesterol status, and hormone levels were also measured. Despite marked differences in glucose/insulin ratio [6.1 +/- 1.1 mmol/pmol (PCOS) vs. 9.9 +/- 0.6 (controls)] and free androgen index [11.9 +/- 2.3 (PCOS) vs. 3.7 +/- 0.6 (controls); normal, <5], we did not find evidence of impaired endothelial function in our patients with PCOS. Both endothelium-dependent (8.7 +/- 3.1%) and endothelium-independent (23.2 +/- 3.4%) vascular responses were normal, and practically identical to the responses seen in the control group (endothelium-dependent, 9.0 +/- 0.7; endothelium-independent, 23.0 +/- 1.2%). The PCOS women were more obese, but baseline brachial arterial diameters were not different between groups. There was no correlation between degree of insulin resistance or hyperandrogenism and the brachial response. This group of healthy obese young women with insulin resistance and hyperandrogenism due to PCOS had normal endothelium-dependent and -independent vascular responses compared to age-matched controls. The factors resulting in preservation of these response are unclear and warrant further investigation.

Adult↗

The pathology of familial breast cancer: histological features of cancers in families not attributable to mutations in BRCA1 or BRCA2.

Breast cancers arising in carriers of mutations in the breast cancer susceptibility genes, BRCA1 and BRCA2, differ histologically from each other and from breast cancers unselected for a family history. However, a substantial proportion of families with multiple cases of breast cancer is not attributable to these two genes (non-BRCA1/2 families). We have now characterized the pathology of 82 breast cancers from non-BRCA1/2 families. Breast cancers in non-BRCA1/2 families were of lower grade (P = 0.0018), showed fewer mitoses (P < 0.0001), less nuclear pleomorphism (P = 0.0014), less lymphocytic infiltrate (P < 0.0001), a lesser extent of the tumor with a continuous pushing margin (P = 0.004), a lesser extent of the tumor composed of solid sheets of cells (P = 0.0047), less necrosis (P = 0.002), and wereparison with BRCA2 tumors, non-BRCA1/2 tumors were lower grade (P = 0.017) and exhibited less pleomorphism (P = 0.01) and more tubule formation (P = 0.05). In comparison with control breast cancers unselected for a family history of the disease, non-BRCA1/2 tumors were of significantly lower grade (P = 0.001), showed less pleomorphism (P = 0.0002), and had a lower mitotic count (P = 0.003). The results indicate that non-BRCA1/2 breast cancers differ histologically from both BRCA1 and BRCA2 breast cancers and are overall of lower grade. They also suggest that non-BRCA1/2 breast cancers differ from nonfamilial breast cancers, but these differences may be attributable to various types of bias.

BRCA2 Protein↗

Distinct phenotypes associated with increasing dosage of the PLP gene: implications for CMT1A due to PMP22 gene duplication.

Increased dosage of the proteolipid protein (Plp) gene causes CNS disease (Pelizaeus-Merzbacher disease [PMD]), which has many similarities to disorders of the PNS associated with duplication of the peripheral myelin protein-22 (PMP22) gene locus. Transgenic mice carrying extra copies of the wild-type Plp gene provide a valid model of PMD. Variations in gene dosage can cause a wide range of phenotypes from severe, lethal dysmyelination through late-onset demyelination. A predilection for different fiber diameters may occur within the various phenotypes with dysmyelination being more obvious in large fibers and late-onset degeneration predominantly affecting small fibers. Although the frequency of apoptotic oligodendrocytes is increased with high gene dosage, the number of mature oligodendrocytes appears adequate. Oligodendrocytes in the dysmyelinated CNS express a range of genes typical of mature cells, yet are unable to assemble sufficient myelin. Oligodendrocytes contain abnormal vacuoles and stain intensely for PLP and other proteins such as MAG. The findings suggest that with high gene dosage much of the PLP, and possibly other proteins, is missorted and degraded in the lysosomal system.

Animals↗

Primary stenting versus balloon angioplasty in occluded coronary arteries: the Total Occlusion Study of Canada (TOSCA).

BACKGROUND: Balloon angioplasty (PTCA) of occluded coronary arteries is limited by high rates of restenosis and reocclusion. Although stenting improves results in anatomically simple occlusions, its effect on patency and clinical outcome in a broadly selected population with occluded coronary arteries is unknown. METHODS AND RESULTS: Eighteen centers randomized 410 patients with nonacute native coronary occlusions to PTCA or primary stenting with the heparin-coated Palmaz-Schatz stent. The primary end point, failure of sustained patency, was determined at 6-month angiography. Repeat target-vessel revascularization, adverse cardiovascular events, and angiographic restenosis (>50% diameter stenosis) constituted secondary end points. Sixty percent of patients had occlusions of >6 weeks' duration, baseline flow was TIMI grade 0 in 64%, and median treated segment length was 30.5 mm. With 95.6% angiographic follow-up, primary stenting resulted in a 44% reduction in failed patency (10.9% versus 19.5%, P=0.024) and a 45% reduction in clinically driven target-vessel revascularization at 6 months (15.4% versus 8.4%, P=0.03). The incidence of adverse cardiovascular events was similar for both strategies (PTCA, 23.6%; stent, 23.3%; P=NS). Stenting resulted in a larger mean 6-month minimum lumen dimension (1.48 versus 1.23 mm, P<0.01) and a reduced binary restenosis rate (55% versus 70%, P<0.01). CONCLUSIONS: Primary stenting of broadly selected nonacute coronary occlusions is superior to PTCA alone, improving late patency and reducing restenosis and target-vessel revascularization.

Adolescent↗

14 years of follow-up from the Edinburgh randomised trial of breast-cancer screening.

BACKGROUND: The Edinburgh randomised trial of breast-cancer screening recruited women aged 45-64 years from 1978 to 1981 (cohort 1), and those aged 45-49 years during 1982-85 (cohorts 2 and 3). Results based on 14 years of follow-up and 270,000 woman-years of observation are reported. METHODS: Breast-cancer mortality rates in the intervention group (28,628 women offered screening) were compared with those in the control group (26,026) with adjustment for socioeconomic status (SES) of general medical practices. Rate ratios were derived by means of logistic regression for the total trial population and for women first offered screening while younger than 50 years. Analyses were by intention to treat. FINDINGS: Initial unadjusted results showed a difference of just 13% in breast-cancer mortality rates between the intervention and control groups (156 deaths [5.18 per 10,000] vs 167 [6.04 per 10,000]; rate ratio 0.87 [95% CI 0.70-1.06]), but the results were influenced by differences in SES by trial group. After adjustment for SES, the rate ratio was 0.79 (95% CI 0.60-1.02). When deaths after diagnosis more than 3 years after the end of the study were censored the rate ratio became 0.71 (0.53-0.95). There was no evidence of heterogeneity by age at entry and no evidence that younger entrants had smaller or delayed benefit (rate ratio 0.70 [0.41-1.20]). No breast-cancer mortality benefit was observed for women whose breast cancers were diagnosed when they were younger than 50 years. Other-cause mortality rates did not differ by trial group when adjusted for SES. INTERPRETATION: Our findings confirm results from randomised trials in Sweden and the USA that screening for breast cancer lowers breast-cancer mortality. Similar results are reported by the UK geographical comparison, UK Trial of Early Detection of Breast Cancer. The results for younger women suggest benefit from introduction of screening before 50 years of age.

Age Factors↗

Impaired brachial artery endothelial function is not predicted by elevated triglycerides.

OBJECTIVES: The purpose of this study was to determine if patients with modest hyperlipidemia, and no other risk factors for coronary artery disease (CAD), have impaired endothelium-dependent (ED) vasoactivity. BACKGROUND: Hypercholesterolemia impairs ED vasodilation, but the impact of elevated triglycerides on endothelial function is not as well established. METHODS: High-resolution ultrasound was used to determine flow-mediated dilation (FMD) in the brachial artery (BA) after a 5-min arterial occlusion (endothelium-dependent stimulus) and nitroglycerin-induced dilation (endothelium-independent stimulus). We studied 40 healthy controls (Group 1), 38 patients with elevated low-density lipoprotein (LDL) cholesterol (Group 2) and 35 patients with elevated triglycerides (Group 3). Patients were excluded if they had known CAD or other risk factors for CAD, or if they were receiving lipid-lowering or vasoactive medications. RESULTS: Control patients (Group 1) had normal LDL cholesterol (2.6+/-0.8 mmol/liter) and triglyceride levels (1.0+/-0.5 mmol/liter) compared with Group 2 (5.2+/-1.2 mmol/liter, 1.8+/-0.6 mmol/liter) and Group 3 (3.5+/-0.9 mmol/liter, 4.2+/-2.5 mmol/liter) subjects (p < 0.001). Baseline BA diameters were the same across the three groups. There was no significant attenuation of flow-mediated vasodilation (FMD) in either of the hyperlipidemic groups (Group 1: 10.9+/-5.0% vs. Group 2: 8.6+/-6.1% vs. Group 3: 9.4+/-3.9%; p = 0.14). However, nitroglycerin-induced vasodilation was mildly reduced (Group 1: 21.0+/-5.0% vs. 16.9+/-7.6% vs. 17.3+/-7.7%; p = 0.01). By multivariate analysis, after controlling for baseline diameters, only the ratio of LDL/high-density lipoprotein predicted a minor impairment in FMD. CONCLUSIONS: In patients free from other cardiac risk factors, modest elevations of triglycerides or LDL cholesterol do not significantly attenuate BA endothelial-dependent vasodilation. Synergism with other cardiac risk factors may be required to significantly impair endothelial function in these patients.

Adult↗