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Biomedical subjects

C M Williams

Publications and source records attributed to C M Williams.

At least 55 records · Page 3Linked to original sources

Anandamide induces overeating: mediation by central cannabinoid (CB1) receptors.

RATIONALE: Central cannabinoid systems have been implicated in appetite regulation by the respective hyperphagic actions of exogenous cannabinoids, such as delta9-THC, and hypophagic effects of selective cannabinoid receptor antagonists. OBJECTIVE: This study examined whether an endogenous cannabinoid, anandamide, could induce overeating, via a specific action at central (CB1) cannabinoid receptors. METHODS: Pre-satiated male rats (n=18), received subcutaneous injections of anandamide (0.5, 1.0, 5.0, 10.0 mg/kg) before 3-h, nocturnal food intake tests. In a second series of intake tests (n=8), anandamide injection (1.0 mg/kg) was preceded by injection of the specific CB1 receptor antagonist, SR141716 (0.1, 0.5, 1.0 mg/kg SC). RESULTS: All doses of anandamide induced significant overeating, with 1.0 mg/kg being most potent. Additionally, hyperphagia induced by 1.0 mg/kg anandamide was dose-dependently attenuated by SR141716 pretreatment. CONCLUSION: This first demonstration of anandamide-induced, CB -mediated, overeating provides important evidence for the involvement of a central cannabinoid system in the normal control of eating.

Animals↗

The effect of the daily intake of inulin on fasting lipid, insulin and glucose concentrations in middle-aged men and women.

The present study was carried out to examine the effect of the daily intake of 10 g inulin on fasting blood lipid, glucose and insulin levels in healthy middle-aged men and women with moderately raised total plasma cholesterol (TC) and triacylglycerol (TAG) levels. This study was a double-blind randomized placebo-controlled parallel study in which fifty-four middle-aged subjects received either inulin or placebo for a period of 8 weeks. Fasting blood samples were collected before the supplementation period (baseline samples 1 and 2, separated by 1 week) and at weeks 4 and 8, with a follow-up at week 12. Compared with baseline values, insulin concentrations were significantly lower at 4 weeks (P < 0.01) in the inulin group. There was a trend for TAG values, compared with baseline, to be lower in the inulin group at 8 weeks (P < 0.08) returning to baseline concentrations at week 12. On comparison of the inulin and placebo groups, the fasting TAG responses over the 8-week test period were shown to be significantly different (P < 0.05, repeated measures ANOVA), which was largely due to lower plasma TAG levels in the inulin group at week 8. The percentage change in TAG levels in the inulin group during the 8-week study was shown to correlate with the initial TAG level of the subjects (rs -0.499, P = 0.004). We therefore conclude that the daily addition of 10 g inulin to the diet significantly reduced fasting insulin concentrations during the 8-week test period and resulted in lower plasma TAG levels, particularly in subjects in whom fasting TAG levels were greater than 1.5 mmol/l. These data support findings from animal studies that fructans influence the formation and/or degradation of TAG-rich lipoprotein particles, and the insulin data are also consistent with recent studies showing attenuation of insulin levels in fructan-treated rats.

Adult↗

The quantitation of lipoprotein lipase mRNA in biopsies of human adipose tissue, using the polymerase chain reaction, and the effect of increased consumption of n-3 polyunsaturated fatty acids.

OBJECTIVE: To examine the effects of the consumption of fish oils on the gene expression of lipoprotein lipase (LPL, EC 3.1.1.34) in human adipose tissue. In order to measure LPL mRNA in adipose tissue samples obtained by needle biopsy from human volunteers a competitive, reverse transcriptase PCR (RT-PCR) protocol was developed. DESIGN: A randomised controlled, single blind cross over dietary study which compared the effects of a low level n-3 polyunsaturated fatty acids (PUFA) using normal foods enriched with eicosapentaenoic (EPA) and docosahexaenoic (DHA) (test diet), with non-enriched but otherwise identical foods (control). The diets were consumed for a period of 22 d with a wash out period of 5 months between the diets. SETTING: Free-living individuals associated with the University of Surrey. SUBJECTS: Six male subjects with a mean (+/- sd) age of 51.2+/-3.6 y were recruited. MAJOR OUTCOME MEASURES: Pre- and postprandial blood samples were taken for the measurement of triacylglycerol (TAG), postheparin LPL activity and adipose tissue samples for the measurement of LPL mRNA levels. RESULTS: Mean LPL expression values were 4.12 x 10(5) molecules of LPL mRNA per ng total RNA on the control diet and 4.60 x 10(5) molecules of LPL mRNA per ng total RNA on the n-3 PUFA enriched (test) diet. There was no significant difference between the levels of LPL expression following each diet, consistent with the lack of change in TAG levels in response to increased dietary n-3 PUFA intake. However, the change in LPL expression (Test-Control diet) correlated significantly with the change in fasting TAG levels (P = 0.03, R = -0.87 and R2 = 0.75) and with the total area under the TAG-time response curve (P = 0.003, R = -0.96 and R2 = 0.92) in individuals. CONCLUSIONS: These findings, although based on a small number of subjects, suggest that LPL expression may be a determinant of plasma TAG levels. The development of this methodology should allow further elucidation of the effects of dietary manipulation and disease processes on lipid clearance and regulation in human subjects.

Adipose Tissue↗

Eotaxin and eotaxin receptor (CCR3) expression in Sephadex particle-induced rat lung inflammation.

The beta chemokine eotaxin is a potent eosinophil activator and chemoattractant. We examined immunohistochemically eotaxin protein expression in a range of normal rat tissues and in rat lung during Sephadex particle-induced pulmonary inflammation. The time course of eotaxin expression in lung at various time points after Sephadex administration was related to the appearance of eosinophils in the bronchoalveolar lavage fluid and tissue distribution of eotaxin receptor (CCR3) positive cells. Results showed that eotaxin protein was constitutively expressed by both lung airway epithelial cells and gut epithelial cells in normal tissues in the absence of inflammation. During Sephadex induced pulmonary inflammation, eotaxin expression increased in alveolar macrophages prior to the major increase in eosinophil numbers which reached a peak at 72 h. The pattern of eotaxin pulmonary expression and the location of CCR3 receptor positive cells suggest a chemoattractant gradient resulting in migration firstly into the tissue and subsequently through the airway epithelium into the airways. Treatment of rats with the glucocorticoid dexamethasone or the immunosuppressant cyclosporin A reduced eosinophil entry into lung tissue and airways but had no apparent effect on eotaxin expression in vivo, indicating that both these drugs inhibit eosinophil recruitment either by an eotaxin-independent mechanism, or by targetting factors that synergise with eotaxin, or an event post eotaxin expression.

Animals↗

Comparison of four carbon dioxide resurfacing lasers. A clinical and histopathologic evaluation.

BACKGROUND: Several high-energy, pulsed and scanned carbon dioxide (CO2) lasers are currently available for cutaneous resurfacing. Although each laser system adheres to the same basic principles of selective photothermolysis, there are significant differences between lasers with respect to tissue dwell time, energy output, and laser beam profile. These differences may result in variable clinical and histologic tissue effects. OBJECTIVE: The purpose of this study was to examine the in vivo clinical and histopathologic effects of four different high-energy, pulsed or scanned CO2 resurfacing lasers. METHODS: A prospective study using four different CO2 resurfacing lasers (Coherent UltraPulse, Tissue Technologies TruPulse, Sharplan FeatherTouch, and Luxar NovaPulse) was performed. The cheeks of seven patients were divided into four quadrants. Each quadrant was randomly assigned to receive treatment with one of four CO2 lasers. Skin biopsies were obtained intraoperatively from each quadrant, after each of three laser passes, and at 1 and 3 months postoperatively. Blinded clinical assessments of each laser quadrant were made at 1, 3, and 6 months postoperatively by three physicians. Degree of lesional improvement as well as erythema severity, re-epithelialization rates, and presence of side effects were recorded. Blinded histologic examination of laser-treated quadrants was performed to determine the amount of tissue ablation, residual thermal damage, inflammation, and new collagen synthesis. RESULTS: The four CO2 lasers produced equivalent clinical improvement of rhytides and scars. Re-epithelialization occurred in all laser quadrants by day 7. Postoperative erythema was most intense in the quadrants treated by UltraPulse and NovaPulse; however, overall duration of erythema was equivalent for all four laser systems (3 months). Postinflammatory hyperpigmentation was the most frequently encountered side effect and occurred with equal frequency in each quadrant. No scarring, hypopigmentation, or infections were observed. After one laser pass, histologic examination revealed partial ablation of the epidermis with the TruPulse laser and complete epidermal ablation using the UltraPulse, NovaPulse, and FeatherTouch laser systems. The greatest degree of residual thermal damage was seen after FeatherTouch and NovaPulse laser irradiation. New collagen formation was greatest in the UltraPulse and FeatherTouch laser-irradiated quadrants. CONCLUSIONS: Equivalent clinical results were observed using the FeatherTouch, NovaPulse, TruPulse, and UltraPulse CO2 lasers. While postoperative erythema intensity differed between laser systems, total duration of erythema was equivalent. The four lasers under study resulted in minimal residual thermal damage and stimulated new collagen formation within 6 months after treatment.

Adult↗

Effects of inulin on lipid parameters in humans.

Convincing lipid-lowering effects of the fructooligosaccharide inulin have been demonstrated in animals, yet attempts to reproduce similar effects in humans have generated conflicting results. This may be because of the much lower doses used in humans as a result of the adverse gastrointestinal symptoms exhibited by most subjects consuming daily doses in excess of 30 g. Two studies that fed either oligofructose (20 g/d) or inulin (14 g/d) observed no effect on fasting total, LDL or HDL cholesterol, or serum triglycerides. Two other studies that fed inulin either in a breakfast cereal (9 g/d) or as a powdered addition to beverages and meals (10 g/d) reported similar reductions in fasting triglycerides (-27 and -19%, respectively). In one of these studies, total and LDL cholesterol concentrations were also modestly reduced (5 and 7%, respectively). Because animal studies have identified inhibition of hepatic fatty acid synthesis as the major site of action for the triglyceride-lowering effects of inulin, and because this pathway is relatively inactive in humans unless a high carbohydrate diet is fed, future attempts to demonstrate lipid-lowering effects of inulin should consider the nature of the background diet as a determinant of response.

Animals↗

The use of poultry litter as co-substrate and source of inorganic nutrients and microorganisms for the ex situ biodegradation of petroleum compounds.

The purpose of this investigation was to determine the feasibility of utilizing poultry litter as a source of microorganisms, C co-substrate, N, and P to enhance the biodegradation of petroleum compounds in contaminated soil. An initial laboratory-scale study utilized soil contaminated with approximately 3,000 mg/kg (ppm) total petroleum hydrocarbons (TPHC) as diesel fuel. Biotreatment units, each containing 10 L of contaminated soil, were supplemented (0, 1, 10, and 20%, total weight basis) with broiler litter containing 3.65% N and 1.89% P. Petroleum-degrading microorganisms previously enriched from broiler and turkey litter were also inoculated into the litter-treated units. A significant first order rate of TPHC biodegradation was measured for all treatment units containing broiler litter (P < 0.05). Based on these results, a subsequent study was conducted at the site of a commercial facility permitted to treat soil (ex situ) contaminated with hazardous compounds. Soil treatment plots, each containing approximately 1 ton of soil contaminated with approximately 1,200 to 1,600 mg/kg diesel fuel were established. Each plot was replicated four times and the experiment was conducted for 35 d. Treatments were as follows: control, soil only; soil + commercial blend of bioremediation nutrients; soil + commercial fertilizer; soil + poultry litter (1% by volume); soil + poultry litter (10% by volume); soil + pelleted poultry litter (10% by volume). The results showed that the remediation of soil contaminated with petroleum compounds is significantly (P < 0.05) enhanced when supplemented with poultry litter (pelleted or nonpelleted) in concentrations of 10% soil volume. These results demonstrate the potential for a specialized market for the use of poultry litter.

Animals↗

Occupational exposures to blood among emergency medicine residents.

OBJECTIVES: To investigate the epidemiologic characteristics of potentially infectious occupational exposures to blood among emergency medicine (EM) residents. METHODS: A SAEM-sponsored multiple-choice survey was administered anonymously to all EM residents participating in the 1998 American Board of Emergency Medicine in-service examination. Survey questions included resident demographics, use of universal precautions, frequency and types of exposures to blood, and exposure reporting. Residents who experienced at least one exposure were then asked to complete an additional set of questions referring only to their latest exposure. Mean values were calculated for each variable and differences between groups were compared by chi-square analysis. RESULTS: Three thousand one hundred sixty-two surveys were distributed to the resident participants, and 2,985 surveys (94.4%) were returned. Of the participants, 56.1% reported at least one exposure to blood during their EM training. The frequency of this self-reported exposure increased with advancing EM level of training (43% EM-1, 58% EM-2, 64% EM-3, 76% EM-4, p<0.001). Of these residents, 36.6% always followed universal precautions, 54% frequently, and 9.4% sometimes, rarely, or never. Those individuals who "always" followed universal precautions reported significantly fewer exposures than those who did not (p<0.005). The latest exposures were most commonly caused by a solid needle or sharp object (39.4%), by a hollow-bore needle (30.6%), or by eye splashes (17.2%). Of these exposures, 71.7% occurred in the ED setting, and only 46.7% of these exposures were reported to health care providers. CONCLUSION: Emergency medicine residents are frequently exposed to blood, most commonly due to puncture injuries by sharp objects. The rate of exposure reporting is low, which may compromise appropriate postexposure counseling and prophylaxis.

Blood↗

Tuberculosis exposure risk in emergency medicine residents.

OBJECTIVES: To assess purified protein derivative (PPD) test surveillance and respiratory protection practices of emergency medicine (EM) residents, along with the prevalence of PPD test conversion and the development of active tuberculosis (TB) in EM residents. METHODS: The study instrument was an anonymous, self-reporting, multiple-choice survey administered to U.S. and Canadian EM residents. It was distributed for voluntary completion in conjunction with the American Board of Emergency Medicine's annual in-service examination, which was administered February 25, 1998. RESULTS: A total of 89.3% (n = 2,985) of residents eligible to complete the survey completed at least part of it. The majority of residents are PPD-tested once a year. The prevalence of PPD test conversions in EM residents was between 1.4% (36/2,575) and 2.0% (52/2,575). Of the residents who PPD test-converted, the ED was most often the perceived area of TB source exposure (n = 15). Two residents (0.08%) reported having developed active TB, including chest radiographic findings or clinical infection, which equals a 0.14% (95% CI = 0.005 to 0.31) risk of developing active TB over a three-year residency. Half of all the residents do not routinely wear National Institute for Occupational Safety and Health (NIOSH)-approved particulate filtration respirator (PFR) masks in patient encounters at risk for TB exposure. While more than a third of EM residents have not undergone fit testing for a NIOSH-approved PFR mask, the lack of routine easy availability of such masks is the most common reason they are not routinely worn by EM residents during at-risk encounters for TB transmission. CONCLUSIONS: Most surveillance PPD testing of EM residents is performed at intervals recommended by the CDC. TB control programs at institutions sponsoring EM residencies need to improve both compliance with PFR mask fit testing by EM residents and availability of approved PFR masks in appropriate areas of the ED. Despite poor compliance with personal respiratory protection in ED patient encounters at risk for TB transmission, the risk of an EM resident's developing active TB over a three-year residency is low.

Emergency Medical Services↗

Lack of influence of test meal fatty acid composition on the contribution of intestinally-derived lipoproteins to postprandial lipaemia.

The extent and duration of postprandial lipaemia have been linked to risk of CHD but the influence of dietary variables on, and the relative contributions of, exogenous (chylomicron) and endogenous (VLDL) triacylglycerols to the total lipaemic response have not been comprehensively evaluated. In the present study the triacylglycerol, apolipoprotein (apo) B-48 and retinyl ester (RE) responses to three test meals of varying monounsaturated (MUFA) and saturated fatty acid (SFA) content were measured in the triacylglycerol-rich lipoprotein (TRL) fraction of plasma (rho = 1.006 g/ml) for 9 h after meal consumption. Fifteen healthy normolipidaemic young men consumed, on separate occasions, three test meals which were identical apart from their MUFA and SFA contents. Expressed as a percentage of total energy the MUFA/SFA contents of the meals were: (1) 12%/17%; (2) 17%/12% and (3) 24%/5%. The contribution of the intestinally-derived lipoproteins (chylomicrons) to the lipaemic response was investigated by determining the time to reach peak concentration and the total and incremental areas under the time response curves (AUC and incremental AUC) for RE, apoB-48 and triacylglycerol in the TRL fraction. No significant differences in these measurements were observed for the three meals. However, visual comparison of the postprandial responses to the three meals suggested that as meal MUFA content increased there was a tendency for the triacylglycerol, apoB-48 and RE responses to become biphasic as opposed to the typical monophasic response seen with the 12% MUFA/17% SFA meal. Comparison of the apoB-48 and RE responses for the three test meals confirmed other workers' findings of delayed entry of RE relative to apoB-48 in TRL. The value of the two markers in investigating dietary fat absorption and metabolism is discussed.

Adult↗

Inter-relationships between small, dense low-density lipoprotein (LDL), plasma triacylglycerol and LDL apoprotein B in an atherogenic lipoprotein phenotype in free-living subjects.

A predominance of small, dense low-density lipoprotein (LDL) is a major component of an atherogenic lipoprotein phenotype, and a common, but modifiable, source of increased risk for coronary heart disease in the free-living population. While much of the atherogenicity of small, dense LDL is known to arise from its structural properties, the extent to which an increase in the number of small, dense LDL particles (hyper-apoprotein B) contributes to this risk of coronary heart disease is currently unknown. This study reports a method for the recruitment of free-living individuals with an atherogenic lipoprotein phenotype for a fish-oil intervention trial, and critically evaluates the relationship between LDL particle number and the predominance of small, dense LDL. In this group, volunteers were selected through local general practices on the basis of a moderately raised plasma triacylglycerol (triglyceride) level (>1.5 mmol/l) and a low concentration of high-density-lipoprotein cholesterol (<1.1 mmol/l). The screening of LDL subclasses revealed a predominance of small, dense LDL (LDL subclass pattern B) in 62% of the cohort. As expected, subjects with LDL subclass pattern B were characterized by higher plasma triacylglycerol and lower high-density lipoprotein cholesterol (<1.1 mmol/l) levels and, less predictably, by lower LDL cholesterol and apoprotein B levels (P<0.05; LDL subclass A compared with subclass B). While hyper-apoprotein B was detected in only five subjects, the relative percentage of small, dense LDL-III in subjects with subclass B showed an inverse relationship with LDL apoprotein B (r=-0.57; P<0.001), identifying a subset of individuals with plasma triacylglycerol above 2.5 mmol/l and a low concentration of LDL almost exclusively in a small and dense form. These findings indicate that a predominance of small, dense LDL and hyper-apoprotein B do not always co-exist in free-living groups. Moreover, if coronary risk increases with increasing LDL particle number, these results imply that the risk arising from a predominance of small, dense LDL may actually be reduced in certain cases when plasma triacylglycerol exceeds 2.5 mmol/l.

Adult↗

Cholesterol reduction using manufactured foods high in monounsaturated fatty acids: a randomized crossover study.

In two separate studies, the cholesterol-lowering efficacy of a diet high in monounsaturated fatty acids (MUFA) was evaluated by means of a randomized crossover trial. In both studies subjects were randomized to receive either a high-MUFA diet or the control diet first, which they followed for a period of 8 weeks; following a washout period of 4-6 weeks they were transferred onto the opposing diet for a further period of 8 weeks. In one study subjects were healthy middle-aged men (n 30), and in the other they were young men (n 23) with a family history of CHD recruited from two centres (Guildford and Dublin). The two studies were conducted over the same time period using identical foods and study designs. Subjects consumed 38% energy as fat, with 18% energy as MUFA and 10% as saturated fatty acids (MUFA diet), or 13% energy as MUFA and 16% as saturated fatty acids (control diet). The polyunsaturated fatty acid content of each diet was 7%. The diets were achieved by providing subjects with manufactured foods such as spreads, 'ready meals', biscuits, puddings and breads, which, apart from their fatty acid compositions, were identical for both diets. Subjects were blind to which of the diets they were following on both arms of the study. Weight changes on the diets were less than 1 kg. In the groups combined (n 53) mean total and LDL-cholesterol levels were significantly lower at the end of the MUFA diet than the control diet by 0.29 (SD 0.61) mmol/l (P < 0.001) and 0.38 (SD 0.64) mmol/l (P < 0.0001) respectively. In middle-aged men these differences were due to a mean reduction in LDL-cholesterol of -11 (SD 12)% on the MUFA diet with no change on the control diet (-1.1 (SD 10)%). In young men the differences were due to an increase in LDL-cholesterol concentration on the control diet of +6.2 (SD 13)% and a decrease on the MUFA diet of -7.8 (SD 20)%. Differences in the responses of middle-aged and young men to the two diets did not appear to be due to differences in their habitual baseline diets which were generally similar, but appeared to reflect the lower baseline cholesterol concentrations in the younger men. There was a moderately strong and statistically significant inverse correlation between the change in LDL-cholesterol concentration on each diet and the baseline fasting LDL-cholesterol concentration (r -0.49; P < 0.0005). In conclusion, diets in which saturated fat is partially replaced by MUFA can achieve significant reductions in total and LDL-cholesterol concentrations, even when total fat and energy intakes are maintained. The dietary approach used to alter fatty acid intakes would be appropriate for achieving reductions in saturated fat intakes in whole populations.

Adult↗

Markers of intestinally-derived lipoproteins: application to studies of altered diet and meal fatty acid compositions.

BACKGROUND AND AIM: The atherogenic potential of dietary derived lipids, chylomicrons (CM) and their remnants (CMr) is now becoming more widely recognised. To investigate factors effecting levels of CM and CMr and their importance in coronary heart disease risk it is essential to use a specific method of quantification. Two studies were carried out to investigate: (i) effects of increased daily intake of long chain n-3 polyunsaturated fatty acid (LC n-3 PUFA), and (ii) effects of increasing meal monounsaturated fatty acid (MUFA) content on the postprandial response of intestinally-derived lipoproteins. The contribution of the intestinally-derived lipoproteins to total lipaemia was assessed by triacylglycerol-rich lipoprotein (TRL) apolipoprotein B-48 (apo B-48) and retinyl ester (RE) concentrations. METHODS AND RESULTS: In a randomised controlled crossover trial (placebo vs LC n-3 PUFA) a mean daily intake of 1.4 g/day of LC n-3 PUFA failed to reduce fasting and postprandial triacylglycerol (TAG) response in 9 healthy male volunteers. Although the pattern and nature of the apo B-48 response was consistent with the TAG response following the two diets, the postprandial RE response differed on the LC n-3 PUFA diet with a lower early RE response and a delayed and more marked increase in RE in the late postprandial period compared with the control diet, but the differences did not reach levels of statistical significance. In the meal study there was no effect of MUFA/SFA content on the total lipaemic response to the meals nor on the contribution of intestinally derived lipoproteins evaluated as TAG, apo B-48 and RE responses in the TRL fraction. In both studies, the RE and apo B-48 measurements provided broadly similar information with respect to lack of effects of dietary or meal fatty acid composition and the presence of single or multiple peak responses. However the apo B-48 and RE measurements differed with respect to the timing of their peak response times, with a delayed RE peak, relalive to apo B-48, of approximately 2-3 hours for the LC n-3 PUFA diet (p = 0.002) study and 1-1.5 hours for the meal MUFA/SFA study. CONCLUSIONS: It was concluded that there are limitations of using RE as a specific CM marker, apo B-48 quantitation was found to be a more appropriate method for CM and CMr quantitation. However it was still considered of value to measure RE as it provided additional information regarding the incorporation of other constituents into the CM particle.

Adolescent↗

Hyperphagia in pre-fed rats following oral delta9-THC.

Using a pre-feed paradigm, the effects of orally-administered delta9-tetrahydrocannabinol (THC) on low baseline levels of nocturnal feeding were assessed. Following 2-h access to a palatable wet mash diet at dark onset, adult male Lister hooded rats (Charles River) were treated with either sesame seed oil vehicle or delta9- tetrahydrocannabinol (0.063, 0.12, 0.25, 0.5, 1.0, or 2.0 mg/kg). One hour later, rats were allowed ad libitum access to standard chow, and intakes were monitored over the subsequent 24 h. Doses of 0.5, 1.0, and 2.0 mg/kg produced substantial hyperphagia during the first hour of testing. Subsequently, rats compensated for their overconsumption so that 24-h intakes were similar in all conditions. The data confirm anecdotal reports of the orexigenic actions of exogenous cannabinoids and suggest a critical role for endogenous cannabinoid systems in the regulation of appetite.

Administration, Oral↗

Differences in postprandial lipaemic response between Northern and Southern Europeans.

Postprandial lipaemic responses to two test meals were investigated in 30 Northern (15 British and 15 Irish), and 30 Southern (Greeks from Crete) healthy male Europeans. The meals were a saturated fatty acid (SFA) meal, which resembled the fatty acid composition of an average UK diet, and a monounsaturated fatty acid (MUFA) meal in which the fat consisted of olive oil. Habitual diets of the two groups differed, with higher total fat, (P < 0.03) and MUFA (P < 0.0001) and lower polyunsaturated fatty acid (PUFA) (P < 0.0001) intakes in Southern than Northern Europeans. Levels of total MUFA (P < 0.02) and oleic acid (P < 0.004) were also higher in adipose tissue of Southern in comparison to Northern Europeans. In both European groups there were no significant differences in postprandial triglyceride response between the two meal types, SFA or MUFA. However, Northern and Southern Europeans showed significant differences in their patterns of postprandial response in plasma triglycerides (P < 0.0001), apolipoprotein B-48 (P < 0.0001), NEFA (P < 0.0001), insulin (P < 0.0007), and factor VII activity (P-0.03). In the case of NEFA, areas under the response curve were higher following the SFA than the MUFA meal for both groups, (P < 0.003) and were greater in Southern than Northern Europeans (P < 0.002) and apo B-48 responses were lower (P < 0.005). Some of these differences may reflect differences in fasting levels since fasting apolipoprotein B-48 levels were lower (P < 0.01) and fasting NEFA (P < 0.02) and insulin (P < 0.005) were higher in the Southern than in the Northern Europeans. In addition, 9 h postprandial post-heparin lipoprotein lipase activity was lower in the Southern than in the Northern Europeans (P < 0.0006). This is the first report of differences in postprandial lipid, factor VII and insulin responses in Southern and Northern Europeans which may be of importance in explaining the different susceptibilities of these two populations to risk of coronary artery disease.

Adipose Tissue↗