Toxicity of nickel in the marine calanoid copepod Acartia tonsa: Nickel chloride versus nanoparticles

Nickel compounds are widely used in industries and have been massively introduced in the environment in different chemical forms. Here we report the effect of two different chemical forms of nickel, NiCl2 and nickel nanoparticles (NiNPs), on the reproduction of the marine calanoid copepod Acartia tonsa. The behavior of nickel nanoparticles was analyzed with different techniques and with two protocols. In the "sonicated experiment" (SON) NiNP solution was sonicated while in the "non-sonicated experiment" (NON-SON) the solution was vigorously shaken by hand. Final nominal concentrations of 5, 10 and 50mgL(-1) and 1, 5 and 10mgL(-1) NiNPs were used for the acute and semichronic tests, respectively. Nanoparticle size did not change over time except for the highest concentration of 50mgL(-1) NiNPs, in which the diameter increased up to 843nm after 48h. The concentration of Ni dissolved in the water increased with NP concentration and was similar for SON and NON-SON solutions. Our results indicate that sonication does not modify toxicity for the copepod A. tonsa. Mean EC50 values were similar for NON-SON (20.2mgL(-1)) and SON experiments (22.14mgL(-1)) in the acute test. Similarly, no differences occurred between the two different protocols in the semichronic test, with an EC50 of 7.45mgL(-1) and 6.97mgL(-1) for NON-SON and SON experiments, respectively. Acute and semichronic tests, conducted exposing A. tonsa embryos to NiCl2 concentrations from 0.025 to 0.63mgL(-1), showed EC50 of 0.164 and 0.039mgL(-1), respectively. Overall, A. tonsa is more sensitive to NiCl2 than NiNPs with EC50 being one order of magnitude higher for NiNPs. Finally, we exposed adult copepods for 4 days to NiCl2 and NiNPs (chronic exposure) to study the effect on fecundity in terms of daily egg production and naupliar viability. Egg production is not affected by either form of nickel, whereas egg viability is significantly reduced by 0.025mgL(-1) NiCl2 and by 8.5mgL(-1) NiNPs. At NiNP concentration below the acute EC50 (17mgL(-1)) only 9% of embryos hatched after 4 days. Interestingly, the percentage of naupliar mortality (>82%) observed in the semichronic test at the nominal concentration of 10mgL(-1) NiNPs corresponding to almost 0.10mgL(-1) of dissolved Ni, was similar to that recorded at the same Ni salt concentration. Electron microscopical analyses revealed that A. tonsa adults ingest NiNPs and excrete them through fecal pellets. To the best of our knowledge, this is the first study investigating the toxicity of two different forms of Ni on the reproductive physiology of the copepod A. tonsa and showing the ability of the calanoid copepod to ingest nanoparticles from seawater.

Comparing outcomes and costs between contingent and combined first-trimester screening strategies for Down's syndrome

OBJECTIVE

To compare a contingent strategy with a combined strategy for prenatal detection of Down's syndrome (DS) in terms of cost, outcomes and safety.

STUDY DESIGN

The contingent strategy was based on a simulation, removing measurement of the free beta subunit of human chorionic gonadotropin (free βhCG) and calculating the DS risk retrospectively in 32,371 pregnant women who had been screened with the combined strategy in the first trimester. In the contingent strategy, a risk between 1:31 and 1:1000 in the first trimester indicated further testing in the second trimester (alpha-fetoprotein, inhibin A, unconjugated oestriol and free βhCG). The cut-off risk values for the contingent and combined strategies in the first trimester were 1:30 and 1:250, respectively, and the cut-off risk value for integrated screening in the second trimester was 1:250. Costs were compared in terms of avoided DS births, and the ratio of loss of healthy fetuses following invasive procedures per avoided DS birth was calculated.

RESULTS

The combined strategy had sensitivity of 40/44 (90.9%) and a false-positive rate of 2.8%. Corresponding values for the contingent strategy were 39/44 (88.6%) and 1.3%, respectively. Only 11% of pregnant women required tests in the second trimester, and the approximate cost reduction for each avoided DS birth was 5000€. The ratio of lost healthy fetuses following invasive procedures per avoided DS birth improved by up to 0.65.

CONCLUSION

The contingent strategy has similar effectiveness to the combined strategy, but has lower costs and fewer invasive procedures.

Moderate consumption of red wine, but not gin, decreases erythrocyte superoxide dismutase activity: a randomised cross-over trial

BACKGROUND AND AIMS

Several studies have shown that moderate alcohol consumption reduces the risk of coronary heart disease, a disease related to oxidative stress. However, the effects of different alcoholic beverages on antioxidant status are not fully known. Our aim was therefore to compare the effects of a moderate intake of an alcoholic beverage with high polyphenol content (red wine) and another without polyphenol content (gin) on plasma antioxidant vitamins, lipid profile and oxidability of low-density lipoprotein (LDL) particles.

METHODS AND RESULTS

Forty healthy men (mean age, 38 years) were included in a randomised cross-over trial. After a 15-day washout period, subjects received 30 g/ethanol/d as either wine or gin for 28 days. Diet and exercise were monitored. Before and after each intervention, we measured serum vitamins, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase activities, lipid profile, oxidized LDL and LDL resistance to ex-vivo oxidative stress. Compared to gin intervention, wine intake reduced plasma SOD activity [-8.1 U/gHb (95% confidence interval, CI, -138 to -25; P=0.009)] and MDA levels [-11.9 nmol/L (CI, -21.4 to-2.5; P=0.020)]. Lag phase time of LDL oxidation analysis also increased 11.0 min (CI, 1.2-20.8; P=0.032) after wine, compared to gin, whereas no differences were observed between the two interventions in oxidation rate of LDL particles. Peroxide concentration in LDL particles also decreased after wine [-0.18 nmol/mL (CI, -0.3 to-0.08;P=0.020)], as did plasma oxidized LDL concentrations [-11.0 U/L (CI,-17.3 to -6.1; P=0.009)].

CONCLUSION

Compared to gin, red wine intake has greater antioxidant effects, probably due to its high polyphenolic content.

Combining fetal nuchal fold thickness with second-trimester biochemistry to screen for trisomy 21

OBJECTIVE

To assess second-trimester screening for trisomy 21 by combining ultrasound nuchal fold (NF) measurement with maternal serum biochemistry.

METHODS

NF, maternal serum alpha-fetoprotein (AFP) and free beta-human chorionic gonadotropin (beta-hCG) were determined concurrently at 14-19 weeks' gestation in a study population comprising 1813 women with singleton pregnancies, including 1257 unselected women undergoing serum screening for trisomy 21 (1999-2002), and 556 high-risk pregnancies prior to amniocentesis (2003-2005), 402 of whom had positive serum screening tests. The results were expressed in multiples of the gestation-specific normal median (MoMs).

RESULTS

There were 1799 unaffected singleton pregnancies, and their NF values approximately fitted a log Gaussian distribution over a wide range. There was a weak but statistically significant correlation between log NF and log AFP (r = - 0.069, P < 0.005) and the correlation coefficient between log NF and log free beta-hCG was even smaller and not statistically significant (r = 0.038, P = 0.11). Among the seven trisomy 21 pregnancies, the median NF level was 1.53 MoM (geometric mean 1.75 MoM), a highly statistically significant increase compared with unaffected pregnancies (P < 0.0001, one-tail Wilcoxon Rank Sum Test). In pregnancies referred because of positive serum screening tests (391 unaffected, seven cases of trisomy 21, one of monosomy X and three other chromosomal anomalies) the use of NF to modify the serum screening risk would have reduced the invasive procedures in unaffected pregnancies by 46% without affecting the detection rate of trisomy 21 or other anomalies. Statistical modeling predicted that adding NF to AFP and free beta-hCG would increase detection more than would adding unconjugated estriol as well as inhibin-A, an analyte that is difficult to measure with precision.

CONCLUSIONS

The addition of NF measurement to second-trimester biochemical markers improves screening performance, and could overcome drawbacks in the implementation of inhibin-A assay in clinical practice.

Effect of apolipoprotein E polymorphism on renal transplantation

INTRODUCTION

Dyslipidemia is an important cardiovascular risk factor and is implicated in the pathogenesis of chronic graft failure in renal transplant recipients. Apolipoprotein E (apoE), a hepatic glycoprotein involved in lipid metabolism, has been associated with hypercholesterolemia and premature coronary disease.

AIM

This study assessed the impact of apoE polymorphism on the evolution of renal transplant recipients.

METHODS

A total of 517 patients (age, 47 +/- 14 years; 62% men), who had undergone renal transplantation at least 12 months before enrollment, were assessed (mean follow-up, 5.4 +/- 2.2 years). ApoE polymorphisms (E2, E3, and E4 alleles) were analyzed using polymerase chain reaction (PCR) using genomic DNA. Donor-recipient clinical variables were assessed using univariate methods and Cox multivariate regression model.

RESULTS

Genotype frequency was as follows: E2/E2 <1%, E2/E3 10%, E3/E3 71%, E2/E4 2%, E3/E4 16%, and E4/E4 1%, with no differences between sexes. In the univariate study, E2/E4, E3/E4, and E4/E4 genotypes were related with poorer patient survival (P = .0045). In the multivariate study, the E4 allele was associated with a higher independent risk of graft loss (odds ratio [OR], 3.23; 95% confidence interval [CI], 1.44-7.21; P < .0001) and death of the patient (OR, 16.03; 95% CI, 3.28-75.18; P < .0001), but only in patients older than 60 years of age. In patients with the E4 allele, 45% of deaths were due to cardiovascular causes.

CONCLUSIONS

The genetic polymorphism of apoE (E4 allele) has an independent negative impact on patient and graft survival in the long term, particularly in older patients.

Comparison of a high-carbohydrate and a high-monounsaturated fat, olive oil-rich diet on the susceptibility of LDL to oxidative modification in subjects with Type 2 diabetes mellitus

AIMS

To compare the effects of a high-carbohydrate (CHO) diet and a high-monounsaturated fatty acid (MUFA) diet on LDL oxidative resistance in free-living individuals with Type 2 diabetes mellitus.

METHODS

Twenty-two men and women out-patients with Type 2 diabetes, with mean age 61 years and in fair metabolic control (HbA1c<8.0%), were enrolled at a university hospital lipid clinic in a randomized, crossover feeding trial comparing two isocaloric diets for 6 weeks each: CHO (fat, 28% energy) and MUFA (fat, 40% energy) based on virgin olive oil. Outcome measurements were changes in LDL susceptibility to oxidation, body weight, glycaemic control, and lipoprotein profiles.

RESULTS

Planned and observed diets were well matched. Participants preferred the MUFA diet over the CHO diet. The lag time of conjugated diene formation during Cu2+-induced LDL oxidation was similar after the CHO and MUFA diets (36.4 +/- 12.2 min and 36.0 +/- 13.7 min, respectively). Body weight, glycaemic control, total triglycerides, and total, LDL- and HDL-cholesterol levels also were similar after the two diets. Compared with the CHO diet, the MUFA diet lowered VLDL-cholesterol by 35% (P=0.023) and VLDL triglyceride by 16% (P=0.016).

CONCLUSIONS

Natural food-based high-CHO and high-MUFA diets have similar effects on LDL oxidative resistance and metabolic control in subjects with Type 2 diabetes. A MUFA diet is a good alternative to high-CHO diets for nutrition therapy of diabetes because it also has a beneficial effect on the lipid profile and superior patient acceptance.

Effects of atorvastatin on glucose homeostasis, postprandial triglyceride response and C-reactive protein in subjects with impaired fasting glucose

AIMS

To investigate the effects of atorvastatin on glucose homeostasis, the basal and postprandial lipid profiles and the CRP levels (C reactive protein) in subjects with impaired fasting glucose (IFG).

METHODS

Thirty-three subjects (22 men and 11 women) were included in our study. All displayed an IFG (fasting plasma glucose between 6.1 and 7.0 mmol/l) on at least two occasions during the last 6 months prior the study. They were randomly assigned to receive either 40 mg atorvastatin/day (n=16) or placebo (n=17) over 16 weeks, in a double-blind design. Before and after the end of the study all participants underwent on three consecutive days: a 75-g oral glucose tolerance test, a frequent sampling intravenous glucose tolerance test with Minimal Model analysis and a meal tolerance test (glucose, insulin and triglycerides). CRP was measured before and after the treatment period.

RESULTS

CRP decreased significantly in the atorvastatin-treated group compared with the placebo group (percent change respect initial values; -42.3 %[-21.5 to - 63.1] and -9.6%[15.0 to -34.0], respectively, p<0.01). Atorvastatin treatment did not produce any change in oral glucose tolerance categories or induce any change in glucose and insulin response in OGTT. The statin produced a trend towards a significant improvement in insulin sensitivity as expressed by a change in Si from baseline to the end of treatment. Atorvastatin reduced the postprandial response of triglycerides to the meal test compared with placebo (19-26 % across the meal test, p<0.05) correlating with the amelioration observed in Si (-0.34, p<0.05; percentage changes).

CONCLUSION

Our results suggest that the use of statins in subjects with IFG seems to include other potentially beneficial actions in addition to their cholesterol-lowering effects.

Effect of apolipoprotein polymorphisms in renal transplant recipients

Cardiovascular disease (CVD) is the main cause of mortality among long-term renal transplant recipients (RTR). On the other hand, allograft chronic nephropathy is the primary cause of graft loss among long-term RTR. Hyperlipidemia is a predisposing factor for both conditions. Polymorphisms of the apolipoproteins modulate lipid metabolism. The aim of the study was to evaluate the effect of apo A-I, apo A-IV and apo C-III genotypes on the long-term results of renal transplantation. Clinical assessment (renal allograft and patient survival) and genotyping for apo A-I (+83C/T), apo C-III (Sst I), and apo A-IV (Thr347Ser and Gln360His) polymorphisms were evaluated in 516 kidney transplant patients and correlated with the clinical evolution over 12 months. The distribution of the apo A-I (+83C/T) polymorphisms was: CC 91.9%, CT 7.9%, and TT 0.2%. The apo C-III genotype showed: S1S1 84.4%, S1S2 15.2%, and S2S2 0.4%. The apo A-IV (Pvu II) polymorphism was: GG 82%, GT 18%, and 0% TT. Finally, the frequency of apo A-IV (Hinf I) polymorphism was: AA 69%, AT 27%, and TT 4%. The frequency of polymorphisms was similar between men and women. In conclusion, there was no significant influence of apolipoprotein polymorphisms on renal and patient survival.

Effects of estradiol, cyproterone acetate, tibolone and raloxifene on uterus and aorta atherosclerosis in oophorectomized cholesterol-fed rabbits

BACKGROUND

Different hormonal replacement regimens are used for treating climacteric complaints; however, not all of them have the same clinical profile. Cardiovascular disease (CVD) is a major health problem and tibolone, raloxifene, estradiol (alone or with cyproterone acetate) have been added to cholesterol-fed rabbits to study atherosclerosis.

METHODS

A total of 48 cholesterol-fed New Zealand white rabbits were studied for 4 months. Forty rabbits underwent bilateral ovariectomy and the other eight were sham operated (group S). The ovariectomized rabbits were allocated to five groups of eight animals each receiving tibolone (Group T, 6 mg/day), raloxifene (R, 35 mg/day), estradiol valerate (E, 3 mg/day), estradiol valerate plus cyproterone acetate (EC, 3+0.5 mg/day, respectively), and no treatment for the control group (C). The sham group received no treatment too.

RESULTS

After 4 months the percentage of the extent of atherosclerosis in the aorta was 30.4% in C group, 24.5% in S group, 10.2% in T group, 30.3% in R group, 17.9% in E group and 28.1% in EC group (P<0.05 T vs. C, R, EC). The aortic cholesterol content compared with aortic weight was 8.55 microg/mg in C group, 11.97 microg/mg in S group, 1.86 microg/mg in T group, 3.82 microg/mg in R group, 2.86 microg/mg in E group and 5.24 microg/mg in EC group (P<0.05 T vs. EC, C, S; R vs. C, S; E vs. C, S). Uterine weights in grams were: 1.89 (C group), 2.24 (S), 7.38 (T), 1.94 (R), 9.92 (E), and 5.94 (EC); P<0.05 (C, S, R, vs. T, E, EC; T vs. E; EC vs. T, E).

CONCLUSION

Our study showed a decrease in the extent of aortic atherosclerosis in oophorectomized cholesterol-fed rabbits treated with tibolone or estradiol, and a decrease in aortic cholesterol content in rabbits treated with tibolone, raloxifene and estradiol. However, rabbits treated with tibolone showed an increased uterine weight, which is contrary to that observed in humans.

Polymorphism in intron 2 of islet amyloid polypeptide gene is associated with lower low-density lipoprotein cholesterol in nondiabetic subjects and in type 2 diabetic patients

The aim of this study was to investigate the presence of mutations in the islet amyloid polypeptide (IAPP) gene in a Spanish population with type 2 diabetes and gestational diabetes mellitus (GDM). Using polymerase chain reaction single-stranded conformation polymorphism, we examined the coding region and the 5'-untranslated region (UTR) of the IAPP gene in 177 unrelated type 2 diabetic patients, 110 healthy control subjects, 38 women with GDM, and 38 gestational control subjects. Mutations were confirmed by DNA sequencing. A heterozygous C-to-A nucleotide substitution at +79 bp in intron 2 of the IAPP gene was detected. The frequencies of the +79-bp polymorphism (A allele) were 6.8% in type 2 diabetic patients, 7.7% in nondiabetic control subjects, 11.8% in women with GDM, and 9.2% in gestational control subjects. No AA genotypes were detected. Nondiabetic subjects and patients with type 2 diabetes bearing the CA genotype had lower low-density lipoprotein (LDL) cholesterol levels than subjects bearing wild genotype. Multivariate logistic regression analysis showed an independent association (p < 0.001; odds ratio: 0.33; 95% confidence interval: 0.17-0.63). We did not detect any sequence variant within exons 1 or 2. One diabetic patient was heterozygous for a silent mutation at codon 31 of exon 3 (Asn31 AAC --> AAT). Our findings indicate that the presence of the +79-bp polymorphism of the IAPP gene in nondiabetic subjects and in patients with type 2 diabetes is associated with lower levels of LDL cholesterol. Furthermore, abnormalities of the coding regions or the 5'-UTR of the IAPP gene are not associated with type 2 diabetes or GDM in the Spanish population.

Serum antibodies to oxidized low-density lipoprotein in pregnant women with preeclampsia and chronic hypertension: lack of correlation with lipid peroxides

OBJECTIVES

To evaluate the circulating levels of antibodies to oxidized low-density lipoprotein (LDL) and their correlation with the lipid peroxide/vitamin E ratio in pregnant women with preeclampsia and chronic hypertension.

METHODS

Antibodies to oxidized LDL were measured by enzyme-linked immunoassay, lipid peroxides (malondialdehyde), and vitamin E were measured by high-pressure liquid chromatography. Patients were 25 healthy pregnant women, 20 previously nonhypertensive women diagnosed with preeclampsia, and 20 women with uncomplicated chronic hypertension.

RESULTS

Serum levels of antibodies to LDL in preeclamptic patients were similar to controls, whereas women with chronic hypertension showed a trend for increased mean levels. Lipid peroxides in serum were significantly increased and vitamin E levels were significantly decreased in preeclampsia with respect to nonhypertensive pregnancy, but no differences were observed for chronic hypertensive women.

CONCLUSIONS

Our results suggest that preeclampsia is not accompanied by increased levels of antibodies to oxidized LDL. By contrast, and according to previous studies in nonpregnant patients, chronic hypertensive patients showed a trend for elevated levels.

Bone mineral density in young, hypothalamic oligoamenorrheic women treated with oral contraceptives

OBJECTIVE

To evaluate whether decreasing doses of ethinyl estradiol affect bone loss related to hypothalamic amenorrhea.

STUDY DESIGN

Sixty-four women with hypothalamic oligoamenorrhea were allocated to two therapy groups: group A (n = 24) received an OC containing 0.030 mg of ethinyl estradiol (EE) and 0.15 mg of desogestrel. Group B (n = 22) received an OC containing 0.020 mg of EE and 0.15 mg of desogestrel. Eighteen women who did not wish to use hormonal therapy constituted the control group (C). Calcium, phosphate and osteocalcin were measured basally and at 6 and 12 months of follow-up. Bone mineral density at the lumbar spine was determined before initiation of the study and at 12 months by dual energy X-ray absorptiometry.

RESULTS

Serum calcium, phosphate and osteocalcin were significantly reduced by both active treatment regimens, whereas no differences were observed in the control group. Bone mineral density at 12 months showed an increase in both therapy groups (A, 2.4%; B, 2.5%), while group C showed a significant decrease (1.2%, P < .05).

CONCLUSION

Both doses of EE were equally effective in preventing bone loss related to hypoestrogenism in hypothalamic oligoamenorrheic subjects.

Inhibin A serum levels in proteinuric and nonproteinuric pregnancy-induced hypertension: evidence for placental involvement in gestational hypertension?

OBJECTIVES

To evaluate the serum levels of inhibin A in pregnant women with different types of hypertension.

METHODS

A case-control study, including 60 cases (20 women with preeclampsia, 20 with mild gestational hypertension, and 20 with chronic hypertension), and 60 gestational-age- and parity-matched controls. Inhibin A was measured in duplicate by enzyme-linked immunosorbent assay in serum samples frozen at -80 degrees C.

RESULTS

As compared to controls, inhibin A levels were significantly elevated in women with preeclampsia ¿2.32 standard deviation (SD) 1.4¿ versus 0.50 (0.29) ng/mL, p < 0.001) and gestational hypertension [1.09 (0.73) versus 0.55 (0.29) ng/mL, p < 0.05], but not in the group of chronic hypertension [0.88 (0.69) versus 0.54 (0.39) ng/mL, p = 0.08]. Overlap in inhibin A values between cases and controls was observed in 20% (4/20) of women with preeclampsia and 55% (11/20) with gestational hypertension.

CONCLUSIONS

Increased serum inhibin A may indicate that a proportion of mild nonproteinuric hypertension cases are associated with placental involvement.

High-monounsaturated fat, olive oil-rich diet has effects similar to a high-carbohydrate diet on fasting and postprandial state and metabolic profiles of patients with type 2 diabetes

Whether metabolic control in type 2 diabetes mellitus (DM) is best achieved with the traditional high-carbohydrate (CHO), low-fat diet or a low-CHO, high-fat diet is still controversial. In a randomized crossover study, we compared the effects of a low-fat (30% of daily energy) diet and a high-fat (40% of daily energy), high-monounsaturated-fat diet for 6 weeks each on fasting and postprandial glucose, insulin, and lipoprotein concentrations in 12 patients with well-controlled type 2 DM (fasting blood glucose, 176 +/- 54 mg/dL; hemoglobin A1c, 6.4% +/- 0.7%) and no overt dyslipidemia (serum total cholesterol, 235 +/- 43 mg/dL; triglycerides, 180 +/- 63 mg/dL). Home-prepared foods were used and olive oil was the main edible fat, accounting for 8% and 25% of daily energy requirements in the low-fat and high-fat diets, respectively. For postprandial studies, the same mixed meal containing 36% fat was used in both dietary periods. Body weight and fasting and 6-hour postprandial blood glucose, insulin, and lipoprotein levels were similar after the two diets. The mean incremental area under the curve of serum triglycerides 0 to 6 hours after the challenge meal, adjusted for baseline levels, did not change significantly after the high-fat diet compared with the low-fat diet (1,484 +/- 546 v 1,714 +/- 709 mg x 6 h/dL, respectively, P = .099). Mean postprandial triglyceride levels at 6 hours were increased about 2 times over fasting levels and were still greater than 300 mg/dL after either diet. A diet high in total and monounsaturated fat at the expense of olive oil is a good alternative diet to the traditional low-fat diet for patients with type 2 DM. However, ongoing postprandial hypertriglyceridemia with either diet points to the need for other therapies to decrease triglyceride-rich lipoproteins (TRL) and the inherent atherogenic risk in type 2 diabetics.

Aging is associated with increased lipid peroxidation in human hearts, but not with mitochondrial respiratory chain enzyme defects

BACKGROUND

Aging is associated with increased oxidative damage at multiple cellular and tissular levels. A decrease in mitochondrial function has repeatedly been advocated as a primary key event, especially on the basis of analysis of skeletal muscle mitochondria. However, some doubts on this issue have arisen when confounding variables (such as physical activity or smoking habit) have been taken into account in the analysis of mitochondrial respiratory chain (MRC) enzyme activities or when additional analytical parameters such as enzyme ratios have been considered.

OBJECTIVE

To determine whether oxidative damage and enzyme activities of the MRC are influenced by the aging process in human hearts.

PATIENTS AND METHODS

We studied cardiac muscle obtained from 59 organ donors (age: 56+/-12 years, 75% men). Oxidative membrane damage was evaluated through the assessment of lipid peroxidation. Absolute and relative enzyme activities (AEA and REA, respectively) of complex I, II, III and IV of the MRC were spectrophotometrically measured. Stoichiometric relationships among MRC complexes were also assessed through calculating MRC ratios. Linear regression analyses were employed to disclose any potential correlation between mitochondrial dysfunction and aging.

RESULTS

We found a progressive, significant increase of heart membrane lipid peroxidation with aging (P<0.05). Conversely, neither AEA nor REA decreased with age (P=n.s. for all complexes). Similarly to observations in other tissues, we found that stoichiometry of the MRC enzymes is maintained within a narrow range in human hearts. When the effects of aging on MRC ratios were explored, we failed again in demonstrating any subtle disarray.

CONCLUSION

MRC enzymes remain preserved in heart with aging, and thus they cannot be considered the main cause of the increased oxidative damage associated with aging.

Substituting walnuts for monounsaturated fat improves the serum lipid profile of hypercholesterolemic men and women. A randomized crossover trial

BACKGROUND

It has been reported that walnuts reduce serum cholesterol levels in normal young men.

OBJECTIVE

To assess the acceptability of walnuts and their effects on serum lipid levels and low-density lipoprotein (LDL) oxidizability in free-living hypercholesterolemic persons.

DESIGN

Randomized, crossover feeding trial.

SETTING

Lipid clinic at a university hospital.

PATIENTS

55 men and women (mean age, 56 years) with polygenic hypercholesterolemia.

INTERVENTION

A cholesterol-lowering Mediterranean diet and a diet of similar energy and fat content in which walnuts replaced approximately 35% of the energy obtained from monounsaturated fat. Patients followed each diet for 6 weeks.

MEASUREMENTS

Low-density lipoprotein fatty acids (to assess compliance), serum lipid levels, lipoprotein(a) levels, and LDL resistance to in vitro oxidative stress.

RESULTS

49 persons completed the trial. The walnut diet was well tolerated. Planned and observed diets were closely matched. Compared with the Mediterranean diet, the walnut diet produced mean changes of -4.1% in total cholesterol level, -5.9% in LDL cholesterol level, and -6.2% in lipoprotein(a) level. The mean differences in the changes in serum lipid levels were -0.28 mmol/L (95% CI, -0.43 to -0.12 mmol/L) (-10.8 mg/dL [-16.8 to -4.8 mg/dL]) (P<0.001) for total cholesterol level, -0.29 mmol/L (CI, -0.41 to -0.15 mmol/L) (-11.2 mg/dL [-16.3 to -6.1 mg/dL]) (P<0.001) for LDL cholesterol level, and -0.021 g/L (CI, -0.042 to -0.001 g/L) (P = 0.042) for lipoprotein(a) level. Lipid changes were similar in men and women except for lipoprotein(a) levels, which decreased only in men. Low-density lipoprotein particles were enriched with polyunsaturated fatty acids from walnuts, but their resistance to oxidation was preserved.

CONCLUSION

Substituting walnuts for part of the mono-unsaturated fat in a cholesterol-lowering Mediterranean diet further reduced total and LDL cholesterol levels in men and women with hypercholesterolemia.

Comparative effects of estrogens plus androgens and tibolone on bone, lipid pattern and sexuality in postmenopausal women

BACKGROUND

The main goals of estrogen replacement therapy (ERT) are the prevention of osteoporosis and cardioprotection and the improvement of quality of life (QL). Androgens and tibolone therapy may increase bone mineral density (BMD) to a greater extent than ERT and offer an increase in QL. Lipid and cardiovascular effects, however, are still a major concern.

AIM

To evaluate whether the addition of a weak androgen to ERT may improve postmenopausal bone loss and sexual activity without adverse effects on lipid pattern and to compare these effects with those observed after tibolone therapy.

SUBJECTS AND METHODS

This prospective study enrolled 120 surgical postmenopausal women; of these, 96 completed the 1-year follow-up. Patients were allocated to one of four groups. The first group (A; n = 23) received 4 mg of estradiol valerate plus 200 mg of enanthate of dihydroandrosterone im monthly. The second group (E; n = 26) received 50 microg/day of transdermal 17-b-estradiol continuously; the third (T; n = 23) received 2.5 mg of tibolone every day; and finally, the fourth group (C; n = 24) constituted a treatment-free control group. Bone mass (dual X-ray absorptiometry), serum total cholesterol, HDL, LDL, triglycerides, apolipoproteins A1 and B and sexual activity were evaluated before starting therapy and at the end of follow-up.

RESULTS

All active treatment groups showed an increase in BMD. This increase was higher in the A treatment group (4.08% P < 0.01). Sexuality improved significantly with therapy; however, tibolone and androgens increased scores to a greater extent than ERT. Androgen therapy was associated with significant increases in total cholesterol, LDL and triglycerides. Cholesterol and LDL fall into groups E and T, HDL into groups A and T and triglycerides in group T only.

CONCLUSION

The combined regimen of androgens and ERT increased vertebral bone mass and enhance sexual activity in postmenopausal women equal to that of tibolone and to a greater extent than ERT alone; its effects on lipids, however, are clearly adverse.

Serum and placental lipid peroxides in chronic hypertension during pregnancy with and without superimposed preeclampsia

OBJECTIVE

To evaluate the circulating levels of lipid peroxides and vitamin E, and the placental levels of lipid peroxides in chronic hypertensive pregnant women, with and without superimposed preeclampsia, as compared to controls and women with primary preeclampsia.

METHODS

Lipid peroxides were measured in serum and placenta by the thiobarbituric acid method and high-pressure liquid chromatography (HPLC), and vitamin E by HPLC. Patients were 36 healthy pregnant women, 34 previously nonhypertensive women diagnosed with preeclampsia, 20 women with uncomplicated chronic hypertension, and 11 women with chronic hypertension complicated by superimposed preeclampsia.

RESULTS

Lipid peroxides in serum and placental tissue were significantly increased, and vitamin E levels in serum were significantly decreased in women with primary preeclampsia and superimposed preeclampsia, as compared to controls. The group of uncomplicated chronic hypertension presented with similar values of lipid peroxides and vitamin E to controls.

CONCLUSIONS

Our results support the clinical assumption that chronic hypertension aggravated by the development of proteinuria represents a superimposed condition associated with placental disease. The data further support the concept that increased lipid peroxides are not merely associated with the presence of hypertension in pregnancy, but they are implicated in the pathophysiology of preeclampsia.

Two-year prospective and comparative study on the effects of tibolone on lipid pattern, behavior of apolipoproteins AI and B

OBJECTIVE

To investigate long-term lipid and lipoprotein changes in postmenopausal women treated with tibolone in a prospective study using appropriate control groups.

DESIGN

Seventy-six of 105 postmenopausal women initially selected for this study completed the 2-year follow-up. Patients were allocated into three groups. The first received 2.5 mg/day tibolone continuously (n = 27; group T), the second received 0.625 mg/day conjugated equine estrogen plus 2.5 mg/day of medroxyprogesterone (group E-P) continuously (n = 25), and a third group contained an additional 24 women who did not receive replacement therapy; these constituted the untreated control group (group C). Plasma lipids and lipoproteins were determined in all patients before joining the study and also at 12 and 24 months after being included.

RESULTS

Women treated with tibolone experienced the greatest decreases in cholesterol, both total and high density lipoprotein (HDL), and triglycerides (TG), whereas the highest increase in HDL was observed in the group E-P. A decrease in low density lipoprotein levels was detected in both therapy groups, whereas a significant increase was observed in the control group. TG were increased after E-P therapy. In all the groups, apolipoprotein AI showed parallel trends to HDL and apolipoprotein B to low density lipoprotein.

CONCLUSIONS

Both therapy groups, tibolone and E-P, induced changes in levels of plasma lipids, lipoproteins and apolipoproteins. Long-term tibolone treatment is associated with a marked and significant decrease in HDL apolipoprotein AI and TG, an effect that defines the major difference with standard HRT. Clearly, further studies are necessary to establish the definite risk/benefit ratio of tibolone with respect to its overall effect on lipid metabolism.

Lipid and protein metabolism in asthma. Effects of diet and corticosteroid therapy

BACKGROUND

Because little is known about the effects of asthma and asthma therapy on lipid and protein metabolism, we have investigated the characteristics of diet and plasma/serum levels of fat and protein in a group of asthma patients with various degrees of severity.

METHODS

A case-control study was carried out on 118 asthma patients recruited from an outpatient clinic and 121 healthy subjects. Asthma severity was characterized in four groups according to clinical symptoms, lung-function tests, and therapy. Normal dietary intake was estimated from a food frequency questionnaire. Serum protein, albumin, and fatty acids were determined by standard methods.

RESULTS

The dietary energy intake of the asthmatics was significantly lower than that of the controls. However, no differences in the body mass index were found between asthma patients and healthy subjects. There were no differences in serum/plasma levels in any of the measured biochemical parameters between healthy subjects and asthmatics. Plasma levels of protein and albumin were significantly lower in severely corticosteroid-dependent patients. There was a significant negative correlation between plasma protein (r=0.36, P<0.05) and plasma albumin levels (r=0.43, P<0.01) and the daily dose of oral corticosteroids. We did not find any differences in plasma levels of cholesterol, HDL-cholesterol, LDL-cholesterol, and fatty acids between cortico-dependent patients and those not receiving this therapy. No correlation was found between any biochemical parameters and the daily dose of inhaled corticosteroids.

CONCLUSIONS

Our results suggest that asthma induces a decrease in energy intake that does not result in a decreased body weight. Inhaled corticosteroids do not exert any metabolic effect, whereas severe asthma with regular oral corticosteroid therapy is associated with reduced plasma protein and albumin levels.

Ossein-hydroxyapatite compounds for preventing postmenopausal bone loss. Coadjuvant use with hormone replacement therapy

OBJECTIVE

To evaluate whether the addition of an ossein-hydroxyapatite compound (OHC) may improve the effect of hormone replacement therapy (HRT) on postmenopausal bone loss.

STUDY DESIGN

Of the 118 recent surgically postmenopausal women initially selected for this open study, 96 completed one-year follow-up. Patients were allocated into four groups. The first group received 50 micrograms/d of transdermal 17-beta estradiol continuously (group E, n = 23), the second received 3.32 g/d of an OHC every day (group OHC, n = 23), the third received 50 micrograms/d of transdermal 17-beta estradiol continuously plus 3.32 g/d of the OHC every day (group E-OHC, n = 26), and an additional 24 women were used as untreated controls (group C). Bone mass, assessed by dual x-ray absorptiometry, was measured prior to and at the end of treatment. Samples, including serum calcium, phosphate and osteocalcine level, were collected before therapy and during the 6th and 12th treatment months.

RESULTS

All treatment groups showed an increase in bone mineral content. This increase was higher in the E-OHC group (4.7%, P < .01). Concomitant biochemical effects at 6 and 12 months were compatible with the observed effects on bone mineral.

CONCLUSION

The combined regimen of OHC and HRT increased vertebral bone mass in postmenopausal women to a greater extent than did OHC or HRT alone, suggesting that this drug combination may be useful in the management of postmenopausal bone loss.

First-trimester biochemical markers for Down syndrome

The value of maternal serum pregnancy-associated protein A (PAPP-A), free and total beta human chorionic gonadotrophin (fbetahCG, betahCG) and alpha-fetoprotein (AFP) in screening for Down syndrome (DS) in early pregnancy has been assessed. To evaluate the different biochemical markers, 32 DS pregnancies and 267 controls were used for AFP, betahCG and PAPP-A. A subgroup of those (17 DS and 136 controls) were used to evaluate fbetahCG. All analytes were determined in fresh serum samples. Our results give support to the feasibility of maternal serum levels of PAPP-A as the best biochemical marker for DS in the first trimester, and either betahCG or fbetahCG as the second marker. No differences were found between betahCG and fbetahCG distribution levels as expressed as MoMs in normal and DS pregnancies in this study.

Randomized crossover study of gemfibrozil versus lovastatin in familial combined hyperlipidemia: additive effects of combination treatment on lipid regulation

The most appropriate therapy for combined hyperlipidemia remains to be determined. We compared the lipid-regulating effects of gemfibrozil and lovastatin in 30 patients with familial combined hyperlipidemia (FCHL) in a randomized, double-blind, placebo-controlled crossover study including 8-week courses of one drug followed by a washout period and a crossover phase to the alternate drug. After completion of the trial, open-label combination therapy was given for up to 12 months. Lovastatin was more efficacious than gemfibrozil in the reduction of total cholesterol (23% v. 9%, P<.001) and low-density lipoprotein (LDL) cholesterol (28% v. 2%, P<.001), whereas gemfibrozil surpassed lovastatin in the reduction of triglycerides (48% v. 0%, P<.001) and very-low-density lipoprotein (VLDL) cholesterol (50% v. 19%, P = .005) and the increase of high-density lipoprotein (HDL) cholesterol (18% v. 4%, P = .005). Lovastatin caused a greater decline in total apolipoprotein B (apo B) and LDL apo B than gemfibrozil, whereas VLDL apo B decreased only after gemfibrozil therapy. Drug-induced changes in lipoprotein composition indicated that gemfibrozil reduced both the number and size of VLDL particles and lovastatin decreased the number of LDL particles. Combined treatment was safe and had additive effects on lipids, causing significant (P<.001) reductions in total cholesterol (32%), triglycerides (51%), LDL cholesterol (34%), and apo B (26%) and an increase in HDL cholesterol (19%). Target LDL cholesterol levels were achieved only in 11% of patients given gemfibrozil alone and triglycerides decreased to target levels in 22% after lovastatin alone, whereas combined therapy normalized both lipid fractions in 96% of patients. Thus, in FCHL, gemfibrozil has no effect on LDL cholesterol levels but favorably influences the putative atherogenic alterations of lipoprotein composition that are related to hypertriglyceridemia. Conversely, lovastatin markedly decreases LDL cholesterol but has little effect on triglyceride-rich lipoproteins. Combination treatment safely corrects all of the lipid abnormalities in most patients.

Lipid peroxide and vitamin E patterns in pregnant women with different types of hypertension in pregnancy

OBJECTIVES

We sought to evaluate the circulating levels of lipid peroxides and vitamin E and the placental levels of lipid peroxides in pregnant women with different types of hypertension.

STUDY DESIGN

Lipid peroxides were measured in serum and placental tissue by the thiobarbituric acid method and high-pressure liquid chromatography, and vitamin E was measured by high-pressure liquid chromatography. The patients studied were 36 healthy pregnant women and 92 women with hypertension classified as having mild gestational hypertension (n = 28), severe gestational hypertension (n = 10), preeclampsia (n = 34), and chronic hypertension (n = 20).

RESULTS

Lipid peroxides in serum and placental tissue were significantly increased, and vitamin E levels in serum were significantly decreased in women with severe gestational hypertension and preeclampsia compared with controls. The groups of mild gestational hypertension or chronic hypertension had similar values of lipid peroxides or vitamin E as controls.

CONCLUSIONS

Our results suggest that the category of gestational hypertension may be composed of at least two entities with different pathophysiology and support the concept of nonproteinuric preeclampsia.

Lack of interaction of apolipoprotein E phenotype with the lipoprotein response to lovastatin or gemfibrozil in patients with primary hypercholesterolemia

The magnitude of serum lipid changes in response to hypolipidemic drugs varies considerably between individuals. These differences may be due to interactions between genetic and environmental factors that effect drug bioavailability or the capacity of the lipid-regulating enzyme and receptor targets to be affected. The apolipoprotein E (apoE) gene locus has been examined in this regard, but reports are conflicting on the effect of its variability on the response to hypolipidemic drugs. We investigated the effect of apoE polymorphism on the serum lipid response to the hepatic hydroxymethyl glutaryl coenzyme A (HMG CoA) reductase inhibitor lovastatin and the fibric acid derivative gemfibrozil. Lipoprotein changes were assessed after 12 weeks of therapy in 106 patients with primary hypercholesterolemia and combined hyperlipidemia treated with lovastastin and in 63 given gemfibrozil therapy. No significant effect of the apoE phenotypes E3/2, E3/3, or E4/3 on the heterogeneity of lipid responses to either drug was found.

Normal and gestational diabetic pregnancies. Lipids, lipoproteins and apolipoproteins

OBJECTIVE

To evaluate plasma lipids, lipoproteins and apolipoprotein changes induced by gestational diabetes.

STUDY DESIGN

In this case-control study, 60 women between 26 and 32 weeks of pregnancy were allocated to four groups according to lipid status and glucose tolerance: (1) normolipemia and no gestational diabetes, (2) normolipemia and gestational diabetes, (3) hyperlipemia and no gestational diabetes, and (4) hyperlipemia and gestational diabetes. Total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, very low density lipoprotein cholesterol (VLDLc), triglycerides, triglycerides/very low density lipoprotein (VLDL), apolipoproteins (APO) A1 and APO B, APO B-VLDL and APO B/low-density lipoprotein were measured.

RESULTS

There were no statistically significant differences in the normolipemic group of women. Among the hyperlipemic patients, gestational diabetic women showed lower VLDLc when compared to nondiabetic patients.

CONCLUSION

Our results, comparing groups separated groups by lipid status, show that the only difference in lipid profile associated with glucose intolerance is lower VLDLc in hyperlipemic patients.

Umbilical Doppler velocimetry in fetuses with trisomy 18 at 10-18 weeks' gestation

The aim of our study was to obtain measurements of the umbilical artery pulsatility index (PI) in pregnancies before invasive procedures for prenatal diagnosis, in order to investigate its potential prognostic value in predicting trisomy 18. We performed a prospective study including 1785 consecutive women from 10 to 18 weeks with singleton pregnancies undergoing chorionic villus sampling (n = 559) or genetic amniocentesis (n = 1226) in our unit. Doppler measurements were performed transvaginally (tenth to 13th week of gestation) or transabdominally (14th to 18th week of gestation) immediately before the invasive procedure. In 7 out of 10 fetuses subsequently diagnosed as trisomy 18, the PI was above the 95th centile, providing a detection rate of 70 per cent, a specificity of 95.1 per cent, a positive predictive value of 7.7 per cent, and a negative predictive value of 99.8 per cent. When the 90th percentile was assayed as a cut-off, the efficacy of PI as a marker of trisomy 18 yielded a sensitivity of 90 per cent and a specificity of 90.4 per cent, with a positive predictive value of 5.2 per cent and a negative predictive value of 99.9 per cent. We suggest that although the use of a single PI measurement for screening purposes needs to be confirmed by further investigation, trisomy 18 fetuses show an abnormal increase in umbilical PI in the first half of pregnancy, and its relation to the early onset of fetal growth retardation needs to be further explored.

Combining nuchal translucency with umbilical Doppler velocimetry for detecting fetal trisomies in the first trimester of pregnancy

OBJECTIVE

The aim of our study was to evaluate whether the combined use of umbilical artery pulsatility index (UAPI) and nuchal translucency (NT) measurements would be useful in the prediction of fetal chromosomal abnormalities at 10 to 13 weeks of gestation.

DESIGN

A prospective study.

POPULATION AND METHODS

Five hundred and fifty-three consecutive women with singleton pregnancies between 10 and 13 weeks of gestation, who underwent chorionic villus sampling at our institution. UAPI and fetal NT thickness were measured immediately before the invasive procedure. Pregnancies in which structural malformations had been detected by ultrasound were excluded.

RESULTS

Using the 95th centile and 3 mm as the cutoffs for UAPI and NT, respectively, the detection rate for all chromosomal anomalies was 84.2%, with a false positive rate (1-specificity) of 6.6%, a positive predictive value of 31.3%, and a negative predictive value of 99.4%. Out of the 553 tested pregnancies 502 had both parameters within the normal range and only three of them (0.6%) were chromosomally abnormal; in six of the eight cases (75%) in which both parameters were abnormal a chromosome anomaly was present. Of the 43 cases in which only one parameter was abnormal, 10 were chromosomally abnormal (23.2%).

CONCLUSIONS

Our results suggest that the presence of chromosomal anomalies may be strongly suspected when an increased NT thickness (NT > or = 3 mm) is associated with an abnormally high UAPI at 10 to 13 weeks of gestation. The number of cases studied is small, however, and these conclusions are tentative and preliminary. The value of a single measurement of NT and UAPI for screening purposes needs to be substantiated by further investigation.

Apolipoprotein E polymorphism and gallstones

BACKGROUND & AIMS

Apolipoprotein (apo) E is a genetically polymorphic protein influencing lipoprotein metabolism and the risk of both atherosclerosis and Alzheimer's disease. As opposed to common apo E3, apo E2 decreases and apo E4 increases hepatic lipoprotein uptake; hence, apo E4 could promote gallstone formation by increasing hepatic and biliary cholesterol concentrations. This study was designed to evaluate whether apo E polymorphism is related to gallstone risk.

METHODS

apo E phenotype was determined in subjects older than 40 years of age (160 with and 125 without gallstones) and in 61 patients with cholesterol gallstones who underwent cholecystectomy. Bile composition, nucleation time, and gallstone features were analyzed in surgical patients.

RESULTS

The E4/3 phenotype was enriched in both patients with gallstones and those who underwent cholecystectomy, with significantly (P < 0.006) higher epsilon 4 allele frequencies than in gallstone-free subjects (odds ratio, 2.67 [95% confidence limits, 1.23-5.93] and 3.62 [95% confidence limits, 1.49-8.91], respectively); women, but not men, accounted for these differences. The prevalence of the epsilon 4 allele increased with age in patients with gallstones, whereas the opposite occurred in gallstone-free subjects. Biliary lipid and gallstone cholesterol content tended to increase in the sequence E4 > E3 > E2 in patients who underwent cholecystectomy.

CONCLUSIONS

Carrying the apo E4 isoform is a genetic risk factor for cholelithiasis in humans, thus adding another adverse effect of apo E polymorphism on health.

Variation in lipid levels during pregnancy in women with different types of hypertension

OBJECTIVES

To evaluate the levels of serum lipids (cholesterol and triglycerides) in pregnant women with different types of hypertension, at the first, second and third trimesters of pregnancy.

METHODS

Cholesterol and triglyceride levels at the first, second and third trimesters of gestation were recorded for 115 women with hypertension during pregnancy, and 115 healthy pregnant women matched for age and body mass index. Cases were classified as having mild gestational hypertension (25), severe gestational hypertension (15), mild preeclampsia (20), severe preeclampsia (20), chronic hypertension (20), and superimposed preeclampsia (15).

RESULTS

Cholesterol levels were not statistically different between cases and controls in any form of hypertension. At 20 and 34 weeks' gestation, triglyceride levels were significantly higher than controls in women with severe gestational hypertension, mild and severe preeclampsia, and superimposed preeclampsia, but not in mild gestational hypertension or chronic hypertension. The significant elevation in triglycerides was already present at 10 weeks in mild and severe preeclampsia.

CONCLUSIONS

The data suggest that the alterations in lipid metabolism observed in preeclampsia are already present at the first trimester of pregnancy. Women with severe gestational hypertension presented a pattern of triglycerides similar to that of preeclamptic women, but mild gestational hypertension resembled chronic hypertension in this respect. This supports the concept that, although in many cases gestational hypertension represents latent essential hypertension, some of these women, probably the most severe cases, present with true pregnancy-induced hypertension, or nonproteinuric preeclampsia.

Effects of progestogen on lipids, lipoproteins and apolipoproteins during transdermal estrogen replacement therapy with and without medroxyprogesterone acetate

OBJECTIVE

To assess whether the effects on plasma lipids and lipoproteins after oophorectomy differ in patients who receive transdermal estrogen replacement therapy (ERT) with and without progestin.

STUDY DESIGN

Twenty-five healthy, normal-weight, regularly menstruating women who underwent hysterectomy and bilateral oophorectomy for benign diseases received, for one year, transdermal therapeutic systems containing estradiol with daily delivery of 50 micrograms cyclically for 24 days per month plus 2.5 mg/d of oral medroxyprogesterone acetate (MPA) sequentially for the last 12 days of each cycle. After the first year the patients ceased to take MPA. We determined the levels of cholesterol (CHOL), high density lipoprotein (HDL)-CHOL, low density lipoprotein (LDL)-CHOL, triglycerides (TG) and apolipoproteins (apo) A-I and B prior to oophorectomy, one month after surgery and during the 6th and 12th months on estrogen plus progestogen substitution and during the 18th and 24th months without progestogen addition.

RESULTS

After oophorectomy, the patients showed increases in LDL, apo-B and atherogenic index, whereas after hormone replacement therapy the patients exhibited falls in plasma LDL, apo-B and atherogenic index and increases in HDL and apo A-I. No significant changes in total CHOL were observed after surgery or treatment, and TG were decreased. Plasma levels of lipids and lipoproteins during estrogen replacement therapy (ERT) without MPA were not significantly different from those observed during ERT plus MPA.

CONCLUSION

Changes in lipids induced by transdermal ERT were not affected by low doses of MPA.

Early midtrimester fetal nuchal thickness: effectiveness as a marker of Down syndrome

OBJECTIVE

Our purpose was to assess the validity of nuchal thickness in the prediction of Down syndrome in early midtrimester fetuses.

STUDY DESIGN

In 1543 consecutive pregnancies undergoing amniocentesis, primarily for advanced maternal age, nuchal thickness was prospectively measured between 13 and 18 weeks and then correlated with the karyotype obtained from amniotic fluid.

RESULTS

With the cutoff value suggested in the literature (> or = 6 mm), 33.3% (6/18) of the cases of Down syndrome would be detected for a 0.1% (2/1424) false-positive rate, with a positive predictive value adjusted to a prevalence of Down syndrome in the general population of 1:3. To increase the sensitivity of the method, the threshold was lowered to 5 mm, achieving a sensitivity of 77.8% (14/18) for a 2.1% (30/1424) false-positive rate and an adjusted positive value of 1:19.

CONCLUSIONS

In early midtrimester fetuses decreasing the nuchal thickness threshold to 5 mm substantially enhances the detection of Down syndrome with a reasonable false-positive rate.

First-trimester biochemical screening for Down syndrome with the use of PAPP-A, AFP, and beta-hCG

Biochemical screening for Down syndrome (DS) is well established in the second trimester of pregnancy, but there is little information available on its value in the first trimester. This study describes our preliminary results with biochemical screening for DS in the first trimester of pregnancy in order to evaluate its efficacy at this time. Our study population, including 19 DS pregnancies, was evaluated using maternal serum levels of alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (beta-hCG), and pregnancy-associated plasma protein A (PAPP-A). At a false positive rate (FPR) of 5 per cent, the detection rate (DR) for DS is 9 per cent for beta-hCG, 18 per cent for AFP, and 66 per cent for PAPP-A when considering these parameters individually. With different combinations of the analytes, the best detection rates are obtained with the association of PAPP-A and AFP (85 and 82 per cent DR for a 10 and 5 per cent FPR, respectively). Our data support the value of first-trimester biochemical screening for DS and that of PAPP-A as a single marker.

Plasma lipids, lipoproteins and apolipoproteins in hirsute women

OBJECTIVE

To determine whether lipid alterations in hirsute women are due to excessive androgen, low estrogen or to a combination of these abnormalities.

DESIGN

Cross sectional study.

PATIENTS

Forty-five hirsute women between 15 and 39 years of age.

MAIN OUTCOME MEASURES

FSH, LH, 17beta-estradiol, PRL, testosterone, androstenedione, triglycerides and apolipoproteins A-I and B.

RESULTS

Testosterone was correlated with triglycerides (r: 0.76, p<0.01), HDL (r: -0.61, P<0.01) and LDL (r: 0.50, p<0.05). Both HDL (r: 0.66, p<0.01) and LDL (r: -0.57, p<0.01) were correlated with estradiol. Total cholesterol was also correlated with estradiol (r: -0.52, p<0.05). Cross adjusted correlations revealed that, after adjusting for estradiol, lipids were associated with testosterone and that estradiol was also correlated with lipids when adjusted for testosterone.

CONCLUSION

The results suggest that altered lipids in women with hyperandrogenism could result from independent effects of androgens and estrogens.

[Carotid atherosclerosis evaluated by two-dimensional ultrasonography in patients with primary hypercholesterolemia]

BACKGROUND

Two-dimension ultrasonography permits to noninvasively quantify extracoronary atherosclerosis. The objective of this study was to assess preclinical atherosclerosis of the extracranial carotid arteries in patients with primary hypercholesterolemia.

METHODS

Lipid and nonlipid cardiovascular risk factors were evaluated in 206 patients with dyslipidemia (127 men and 79 women, mean age 49 years, range 18-75), and a multifactorial cardiovascular risk profile was constructed for each patient. Ultrasound measurements of the intima-media thickness in the common carotid artery of each side were taken, and the number and height of any atheroma plaques present were quantified.

RESULTS

Asymptomatic plaques were found in 120 patients (58%), and were more frequent in men than in women (65 vs 47%, p = 0.009), and in patients with than in those without prior coronary heart disease (80 vs 50%, p < 0.001). Both intimal thickening, indicative of early atherosclerosis, and the extent of arterial wall involvement with plaques, which represents an advanced stage of the disease, increased significantly with age and with increasing multifactorial cardiovascular risk, reflecting a positive relation between signs of atherosclerosis and the burden of risk factors. Intima-media thickness also increased with increasing plaque score, indicating the generalization of atherosclerosis.

CONCLUSIONS

The high prevalence of preclinical carotid atherosclerosis confirms the atherogenic risk of primary dyslipidemias. The relation between carotid lesions and both coronary heart disease and multifactorial risk supports the validity of arterial ultrasound studies for cardiovascular risk prediction.