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The growing demand for data scientists in both the global and Dutch labour markets has led to an increase in data science and artificial intelligence (AI) master programs offered by universities. However, there is still a lack of clarity regarding the specific skills of data scientists. This study addresses this issue by employing Correlated Topic Modeling (CTM) to analyse the content of 41 master programs offered by 11 Dutch universities and an interuniversity combined program. We assess the differences and similarities in the core skills taught by these programs, determine the subject-specific and general nature of the skills, and provide a comparison between the different types of universities offering these programs. Our analysis reveals that data processing, statistics, research, and ethics are the core competencies in Dutch data science and AI master programs. General universities tend to focus on research skills, while technical universities lean more towards IT and electronics skills. Broad-focussed data science and AI programs generally concentrate on data processing, information technology, electronics, and research, while subject-specific programs give priority to statistics and ethics. This research enhances the understanding of the diverse skills of Dutch data science graduates, providing valuable insights for employers, academic institutions, and prospective students., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Mol et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The patient-physician relationship is a critical determinant of patient health outcomes. Verbal and non-verbal communication, such as eye gaze, are vital aspects of this bond. Neurobiological studies indicate that oxytocin may serve as a link between increased eye gaze and social bonding. Therefore, oxytocin signaling could serve as a key factor influencing eye gaze as well as the patient-physician relationship. We aimed to test the effects of oxytocin on gaze to the eyes of the physician and the patient-physician relationship by conducting a randomized placebo-controlled crossover trial in healthy volunteers with intranasally administered oxytocin (with a previously effective single dose of 24 IU, EudraCT number 2018-004081-34). The eye gaze of 68 male volunteers was studied using eye tracking during a simulated video call consultation with a physician, who provided information about vaccination against the human papillomavirus. Relationship outcomes, including trust, satisfaction, and perceived physician communication style, were measured using questionnaires and corrected for possible confounds (social anxiety and attachment orientation). Additional secondary outcome measures for the effect of oxytocin were recall of information and pupil diameter and exploratory outcomes included mood and anxiety measures. Oxytocin did not affect the eye-tracking parameters of volunteers' gaze toward the eyes of the physician. Moreover, oxytocin did not affect the parameters of bonding between volunteers and the physician nor other secondary and exploratory outcomes in this setting. Bayesian hypothesis testing provided evidence for the absence of effects. These results contradict the notion that oxytocin affects eye gaze patterns or bonding.

Background: Fatigue is frequently reported by patients with type 1 diabetes mellitus. A recent study showed that 40 % of patients experienced severe fatigue that lasted for more than six months and was accompanied by substantial impairments in daily functioning. Currently, there is no effective treatment available for chronic fatigue in patients with type 1 diabetes. Cognitive behaviour therapy aimed at cognitions and behaviours that perpetuate fatigue is effective in reducing fatigue in other chronic diseases. Recent research showed that these cognitions and behaviours are also potential determinants of fatigue in type 1 diabetes. We designed Dia-Fit, a web-based cognitive behaviour therapy for severe and chronic fatigue in patients with type 1 diabetes. This patient-tailored intervention is aimed at reducing fatigue by changing cognitions and behaviours assumed to maintain fatigue. The efficacy of Dia-Fit will be investigated in this study., Methods/design: A randomised controlled trial will be conducted in 120 patients with type 1 diabetes who are chronically and severely fatigued. Patients will be randomised to a treatment or waiting list group. The treatment group will receive Dia-Fit, a blended care therapy consisting of up to eight internet modules and face-to-face sessions with a therapist during a five-month period. The treatment will be tailored to the fatigue-maintaining cognitions and behaviours that are relevant for the patient and are determined at baseline. The waiting list group will receive Dia-Fit after a waiting period of five months. The primary outcome measure is fatigue severity. Secondary outcome measures are functional impairment and glucose control determined by haemoglobin A1c and blood glucose variability., Discussion: To our knowledge, this is the first study investigating the efficacy of a cognitive behavioural intervention for chronic fatigue in patients with type 1 diabetes., Trial Registration: Dutch trial register NTR4312 (10 December 2013).

Background: In patients with type 1 diabetes mellitus (T1DM), cardiovascular events are more common, and the outcome following a myocardial infarction is worse than in nondiabetic subjects. Ischemic or pharmacological preconditioning are powerful interventions to reduce ischemia reperfusion (IR)-injury. However, animal studies have shown that the presence of T1DM can limit these protective effects. Therefore, we aimed to study the protective effect of ischemic preconditioning in patients with T1DM, and to explore the role of plasma insulin and glucose on this effect., Methods: 99mTechnetium-annexin A5 scintigraphy was used to detect IR-injury. IR-injury was induced by unilateral forearm ischemic exercise. At reperfusion, Tc-annexin A5 was administered, and IR-injury was expressed as the percentage difference in radioactivity in the thenar muscle between the experimental and control arm 4 hours after reperfusion. 15 patients with T1DM were compared to 21 nondiabetic controls. The patients were studied twice, with or without ischemic preconditioning (10 minutes of forearm ischemia and reperfusion). Patients were studied in either normoglycemic hyperinsulinemic conditions (n=8) or during hyperglycemic normoinsulinemia (n=7). The controls were studied once either with (n=8) or without (n=13) ischemic preconditioning., Results: Patients with diabetes were less vulnerable to IR-injury than nondiabetic healthy controls (12.8 ± 2.4 and 11.0 ± 5.1% versus 27.5 ± 4.5% in controls; p<0.05). The efficacy of ischemic preconditioning to reduce IR-injury, however, was lower in the patients and was even completely abolished during hyperglycemia., Conclusions: Patients with T1DM are more tolerant to forearm IR than healthy controls in our experimental model. The efficacy of ischemic preconditioning to limit IR-injury, however, is reduced by acute hyperglycemia., Trial Registration: The study is registered at www.clinicaltrials.gov (NCT00184821).

Introduction: Epstein-Barr virus (EBV) establishes lifelong latent infection. In some patients the host-virus balance is disturbed, resulting in a chronic active EBV infection. The following case illustrates the difficulty in diagnosing and treating chronic EBV infection., Case: A 30-year-old woman was referred because of recurrent swellings of lymphatic tissue of both eyelids, orbit and lymph nodes and general malaise since the age of 19. In the past, repeated biopsies showed MALT lymphoma and nonspecific lymphoid infiltrations. Now, a biopsy of an axillary lymph node showed paracortical hyperplasia with a polymorphous polyclonal lymphoid proliferation, and large numbers of EBV-encoded small RNA (EBER) positive cells, consistent with EBV infection. Laboratory investigation showed a high EBV viral load. No evidence of immunodeficiency was found. Chronic active EBV infection (CAEBV) was diagnosed. Treatment with high-dose acyclovir did not significantly reduce the viral load. Rituximab was given in an attempt to reduce the amount of EBV-infected B lymphocytes. However, soon after the second dose the patient died of a sub-arachnoidal haemorrhage., Conclusion: This case report illustrates CAEBV as a rare manifestation of EBV-induced disease, which will be detected more frequently with the use of EBV-EBER hybridisation of lymph nodes and polymerase chain reaction (PCR) for EBV DNA. The prognosis is poor with no established therapeutic strategies.

Chylothorax is defined as an accumulation of chyle in the pleural space caused by disruption of the thoracic duct or one of its major divisions. Chyle has a high content of triglycerides. The odorless fluid is turbid and milky due to the presence of fat containing particles, the chylomicrons. The etiology of chylothorax can be divided into four major categories: tumor, trauma, idiopathic and miscellaneous. Although chylothorax is uncommon, it is a serious and potentially hazardous disorder. Loss of chyle leads to metabolic disturbances, malnutrition and immunodeficiency. Treatment consists of treatment of the underlying disease, conservative treatment (medium chain triglyceride diet, parenteral nutrition) or surgical intervention. Appropriate timing of surgical intervention is essential. Since the ligation of the thoracic duct can be performed during thoracoscopy, this minimal interventional technique is the procedure of choice when conservative treatment fails.

Pregnancy is accompanied by physiological hyperventilation that may be perceived as shortness of breath; causes are a reduced residual capacity and a reduced expiratory reserve volume due to the swelling uterus, and a larger tidal volume due to increase of the progesterone concentration and of the chemosensitivity to CO2 and O2. Fatigue, lowered exercise tolerance and orthopnoea also may occur, as do basal crepitations at auscultation. In pregnant asthma patients the symptoms may either improve greatly or become aggravated. During an asthma attack the foetus is exposed to hypoxaemia, which may be worsened by a decreased uteroplacental blood circulation in case of maternal alkalosis. Poorly controlled asthma has a stronger adverse effect on the unborn child than the judicious use of anti-asthma drugs. Safe drugs against asthma during pregnancy, around parturition and during breast feeding, are cromoglycic acid and ipratropium; relatively safe drugs are short-acting beta-sympathicomimetics, inhalation corticosteroids and systemic corticosteroids, as well as theophylline from the second trimester; use of long-acting beta-sympathicomimetics is advised against.

To evaluate the role of both oxidation and inflammation in atherosclerosis, we compared LDL oxidizability, in vivo lipid and cholesterol oxidation, and basal and lipopolysaccharide (LPS)-stimulated production of various cytokines in normolipidemic patients with diabetes mellitus (DM: n = 11), cigarettes smokers (n = 14). In addition, the effects of vitamin E (600 I.U./day for 4 weeks) on these parameters were evaluated. Initial LDL oxidation characteristics before and after vitamin E were identical in the 3 groups. Plasma thiobarbituric acid reactive substances were higher in DM and smokers versus controls (0.77 +/- 0.22, 0.74 +/- 0.14 versus 0.62 +/- 0.10 mumol malondialdehyde equivalents/l, respectively; P versus controls < 0.05) and normalized after vitamin E supplementation. Total plasma oxysterols were higher in smokers versus controls (354 +/- 104 versus 265 +/- 66 nmol/l, P < 0.05) and unaffected by vitamin E. The basal and LPS-stimulated levels of interleukin-1 beta and tumour necrosis factor alpha (TNF alpha) and the basal level of interleukin-1-receptor antagonist (IL-1RA) were identical for the 3 groups. LPS-stimulated IL-1RA was higher in DM versus controls (10.7 +/- 2.0 versus 8.1 +/- 1.7 pmol/l, P < 0.05). After vitamin E, TNF alpha dropped in controls and smokers, and IL-1RA in smokers only. Results suggest increased in vivo oxidative stress and inflammation in DM and smoking, which is partly overcome by vitamin E.

Transgenic mice overexpressing human APOE*3Leiden are highly susceptible to diet-induced hyperlipoproteinemia and atherosclerosis due to a defect in hepatic uptake of remnant lipoproteins. In addition to the human APOE*3Leiden gene, these mice carry the human APOC1 gene (APOE*3Leiden-C1). To investigate the possible effect of simultaneous expression of the human APOC1 gene, we examined the phenotypic expression in these APOE*3Leiden-C1 mice in relation to transgenic mice expressing the APOE*3Leiden gene without the APOC1 gene (APOE*3Leiden-HCR). APOE*3Leiden-C1 and APOE*3Leiden-HCR mice had comparable liver expression for the APOE*3Leiden transgene and high total cholesterol levels on a sucrose-based diet compared with control mice (4.3 and 4.3 versus 2.1 mmol/L). In addition, on this diet APOE*3Leiden-C1 mice displayed significantly higher serum triglyceride levels than APOE*3Leiden-HCR mice and control mice (4.4 versus 0.6 and 0.2 mmol/L). Elevated triglyceride and cholesterol levels were mainly in the VLDL-sized lipoproteins. In vivo turnover studies with endogenously triglyceride-labeled VLDL showed a reduced VLDL triglyceride fractional catabolic rate for APOE*3Leiden-C1 and APOE*3Leiden-HCR mice compared with control mice (3.5 and 11.0 versus 20.4 pools per hour). To study whether the difference in fractional catabolic rates between the two transgenic strains was due to an inhibiting effect of apoC1 on the extrahepatic lipolysis or hepatic-mediated uptake of VLDL, turnover experiments were performed in functionally hepatectomized mice. Strikingly, both APOE*3Leiden-C1 and APOE*3Leiden-HCR mice showed a decreased lipolytic rate of VLDL triglyceride in the extrahepatic circulation compared with control mice (1.5 and 1.8 versus 6.3 pools per hour). We conclude that next to an impaired hepatic uptake, overexpression of the APOE*3Leiden gene influences the extrahepatic lipolysis of VLDL triglycerides, whereas simultaneous overexpression of the APOC1 gene leads to a further decrease in hepatic clearance of VLDL.

The oxidative modification of low density lipoproteins (LDL) by arterial wall cells is thought to contribute to atherogenesis. Monocyte/macrophages, among other arterial wall cells, oxidatively modify LDL to a form that is recognized by scavenger/oxidized LDL receptors. It has recently been suggested that LDL binding to the LDL receptor (B/E receptor) is essential for macrophage-mediated oxidation of LDL. In the present study, we compared the ability of resident peritoneal macrophages from LDL-R-deficient (LDLR-/-) mice to oxidize LDL with that of resident peritoneal macrophages from C57B6 mice. The LDLR-/- macrophages oxidized LDL at least as rapidly as did the C57B6 macrophages both in F-10 medium and in Dulbecco's modified Eagle's medium supplemented with 1 microM copper (DMEM-Cu2+). Studies were also conducted to examine the effect of preincubation of LDLR-/- and C57B6 macrophages with 10% lipoprotein-deficient serum (LPDS), which up-regulates LDL receptors, or with acetylated LDL (Ac-LDL), which increases cellular cholesterol and down-regulates LDL receptors. Preincubation with 10% LPDS had no significant effect on subsequent LDL oxidation by either type of cells in F10 medium, but the C57B6 cells did show a small (18%) but significant increase in LDL oxidation in DMEM-Cu2+. Preincubation with 50 micrograms/ml Ac-LDL in F10 medium had no effect on LDL oxidation by either LDLR-/- or C57B6 macrophages. Preincubation with 100 micrograms/ml Ac-LDL had no effect on subsequent LDL oxidation by C57B6 cells but, unexpectedly, caused a modest (26%) fall in LDL oxidation by the receptor-negative cells. Using DMEM-Cu2+ medium, preincubation with Ac-LDL reduced LDL oxidation substantially (50-66%) but the effect was just as great in LDL-R negative cells (59-66%) as in C57B6 cells (50-58%), suggesting that the effect is not due to changes in LDL receptor density. It may be related somehow to the Ac-LDL-induced increase in cell cholesterol content. The data demonstrate that the absence of LDL receptors does not reduce the ability of macrophages to oxidize LDL and that LDL binding to LDL receptors is not an essential requirement for macrophage oxidation of LDL.

Apolipoprotein E3-Leiden (APOE*3-Leiden) transgenic mice have been studied to identify factors modulating chylomicron and VLDL remnant lipoprotein metabolism. Transient elevated levels of VLDL/LDL-sized lipoproteins occurred in these mice with maximal levels during the period of rapid growth (optimum at 45 d of age). After about 100 d of age, serum cholesterol and triglyceride levels stabilized to slightly elevated levels as compared to control mice. The expression of the APOE*3-Leiden transgene was not age-dependent. In young mice the in vivo hepatic production of VLDL-triglycerides was 50% increased as compared to older mice. This is sustained by in vivo VLDL-apo B turnover studies showing increased (75%) VLDL-apo B secretion rates in young mice, whereas the VLDL-apo B clearance rate appeared not to be age dependent. On a high fat/cholesterol diet, females displayed significantly higher cholesterol levels than males (10 versus 7.0 mmol/liter, respectively). Serum levels of VLDL/LDL sized lipoproteins increased upon administration of estrogens, whereas administration of testosterone gave the opposite result. As compared to male mice, in female mice the hepatic VLDL-triglyceride production rate was significantly elevated. Injection of estrogen in males also resulted in increased VLDL-triglyceride production, although not statistically significant. In vivo VLDL-apo B turnover experiments showed that the VLDL secretion rate tended to be higher in females. Although, the fractional catabolic rate of VLDL-apo B is not different between males and females, administration of estrogens in males resulted in a decreased clearance rate of VLDL, whereas administration of testosterone in females resulted in an increased clearance rate of VLDL. The latter presumably due to an inhibiting effect of testosterone on the expression of the APOE*3-Leiden transgene. We conclude that hyperlipidemia in APOE*3-Leiden transgenic mice is strongly affected by age via its effect on hepatic VLDL production rate, whereas gender influences hyperlipidemia by modulating both hepatic VLDL production and clearance rate.

Objective: To study the long-term efficacy and safety of the cholesterol synthesis inhibitor, simvastatin, in the treatment of familial hypercholesterolaemia., Methods: This is an open long-term follow-up of patients treated for 5 years or more in the Nijmegen University lipid clinic. Forty-four patients with heterozygous familial hypercholesterolaemia (mean baseline serum cholesterol level 11.5 mmol/l) were treated with simvastatin alone (monotherapy group) in doses ranging from 20 to 80 mg/day, or in combination with other lipid-lowering agents (combination-therapy group)., Results: Over the intervention period of 6 years the mean overall reduction of the serum cholesterol level was 37.8% for the total group, 37.7% for the monotherapy group and 42.6% for the combination-therapy group. The reduction of the low-density lipoprotein (LDL)-cholesterol in the three groups was 45.0, 44.6 and 50.3%, respectively. The serum triglyceride concentration was reduced by 14.0, 20.5 and 12.5%, respectively. The increase in the high-density lipoprotein (HDL)-cholesterol level was 14.4, 16.2 and 14.0%, respectively. One patient died from a myocardial infarction and 2 patients had a non-fatal cardiac event. Two patients stopped taking medication due to side-effects (dizziness and insomnia). Biochemical adverse effects were confined to elevations of the alanine aminotransferase level and the creatine phosphokinase level and did not lead to discontinuation of therapy., Conclusions: Simvastatin proves to be a safe and effective lipid-lowering drug during long-term treatment.

Not only the plasma cholesterol level, but also postsecretory modifications of lipoproteins appear to be of influence in atherogenesis. Evidence that several forms of modification, especially oxidation, occur in vivo is rapidly accumulating, although their clinical relevance remains uncertain. Modification of lipoproteins has been demonstrated in persons with such well-known risk factors of premature atherosclerosis as smoking, diabetes mellitus and hyperlipidaemia. Because there is a relation between the amount of natural antioxidants in the plasma and the risk of atherosclerosis, and because exogenous antioxidants appear to retard atherosclerosis without influencing the plasma cholesterol level, antioxidants may prove to be of use in the prevention of atherosclerosis. There are strong indications for a role of the immune system in atherogenesis. Modified lipoproteins are highly immunogenic and stimulate immunocompetent cells to secrete vasoactive factors and cytokines. From animal studies it appears that pro- and antioxidative conditions can modulate these processes. It is concluded that additional research on the relation between lipoprotein modification and the immune system, and on the possible beneficial effects of antioxidants in atherogenesis is warranted, not only to elucidate further the mechanism of atherosclerosis, but also to develop new approaches to the prevention of atherosclerosis.

1. The major drawback of the cardiovascular reflex tests used to study autonomic failure is the time involved in calculating the results. To overcome this disadvantage, we have developed an automated computerized program using a FINger Arterial PRESsure instrument for the measurement of beat-to-beat heart rate and blood pressure on a finger. 2. This program calculates heart rate variability during three standardized tests, forced breathing, standing up and the Valsalva manoeuvre, and records blood pressure values in response to standing up and sustained handgrip. The time taken to perform the test and to calculate the results is usually 25 min. 3. The reproducibility of the tests in 21 normal subjects was comparable with the reproducibility obtained with conventional test methods using an ECG and a sphygmomanometer. 4. In addition, we determined the age-dependent normal values of the seven test parameters in 124 subjects aged 20-90 years. 5. Using this program in 10 patients with longstanding (14-50 years) complicated diabetes, in each of them four or more abnormal test results were found.

In two inbred strains of rabbit with high or low response of plasma cholesterol to dietary cholesterol, low density lipoprotein (LDL) apolipoprotein (apoLDL) kinetics were determined with the use of a heterologous tracer isolated from a Watanabe heritable hyperlipidemic (WHHL) rabbit. On a diet without added cholesterol, the total clearance of apoLDL (which equals apoLDL production) did not differ significantly between rabbits of both strains. After the feeding of a diet containing 0.1% cholesterol for six weeks, plasma LDL cholesterol, plasma apoLDL and liver cholesterol concentrations rose significantly in the hyperresponsive but not in the hyporesponsive rabbits. Cholesterol feeding depressed the total fractional catabolic rate (FCR) of apoLDL in the hyper- but not in the hyporesponsive rabbits; this was attributed to a decrease of receptor-dependent FCR while receptor-independent FCR was similar in the two strains. On the diet containing cholesterol, the receptor-mediated absolute catabolic rate (ACR) of apoLDL did not differ between hyper- and hyporesponsive rabbits but receptor-independent ACR of apoLDL was higher in hyperresponders. It is concluded that the higher plasma apoLDL levels in hyperresponsive rabbits fed the 0.1% cholesterol diet are caused by a higher production of apoLDL and not by a lower flux of apoLDL through the receptor-mediated pathway.

The influence of interruption of bile-acid enterohepatic circulation by partial ileal bypass (PIB) surgery on serum lipids, lipoproteins and the turnover of very-low- (VLDL) and low-density (LDL) lipoproteins was investigated in Watanabe heritable hyperlipidaemic (WHHL) rabbits. Compared with controls, total serum cholesterol was 48% lower after PIB (16.88 +/- 1.57 versus 8.79 +/- 1.66 mmol/l; P less than 0.01), owing to lower levels of cholesterol in VLDL (-23%), intermediate-density lipoprotein (IDL; -39%) and LDL (-72%); serum triacylglycerols were 32% higher (3.86 +/- 1.35 versus 5.11 +/- 0.82 mmol/l). The ratio of the percentages of mass of cholesteryl esters to triacylglycerols was 71% lower in VLDL and LDL and 67% lower in IDL (P less than 0.01). Compared with controls, the secretion rate of LDL was 33% lower (31.1 +/- 7.2 versus 20.7 +/- 6.9 mg/day per kg; P less than 0.05) and the fractional catabolic rate (FCR) of LDL was 33% higher (0.46 +/- 0.06 versus 0.61 +/- 0.12 pool/day; P less than 0.02). The VLDL turnover showed that after PIB there was a higher secretion rate of VLDL apolipoprotein B (63.9 versus 167.4 mg/day per kg), a higher FCR (3.84 versus 8.61 pools/day), a higher direct uptake (38.8 versus 146.4 mg/day per kg) and a higher conversion of VLDL into LDL (4.8 versus 9.0 mg/day per kg). Some 82% of LDL originated from direct synthesis in controls, and after PIB this was 59%. In both controls and treated rabbits there was a direct LDL synthesis, which was 52% lower after PIB (26.3 versus 12.6 mg/day per kg). It is concluded that LDL-cholesterol lowering by PIB is due to an increased uptake of LDL, a decreased synthesis of LDL, and cholesterol depletion of the LDL particles; the decreased LDL synthesis is due to a decreased direct production of LDL, which exceeds the increased conversion of VLDL into LDL.

The long-term effects (66 weeks) of simvastatin (40 mg in one or two doses per day), an inhibitor of HMG CoA-reductase, were evaluated in 12 patients with familial dysbetalipoproteinaemia (type III hyperlipoproteinaemia). Simvastatin had a persistent hypolipidaemic effect; the mean reduction in serum cholesterol was 36-51%, and the mean reduction in serum triglycerides was 32-55%. The decrease in serum lipids was caused by a decline in VLDL-cholesterol and LDL-cholesterol levels; the mean ratio between VLDL-cholesterol and serum triglycerides decreased significantly from 1.06 to 0.73. There was no significant difference between the once-a-day and twice-a-day regimens. Simvastatin was well tolerated; no serious side-effects were observed. These data demonstrate the usefulness of simvastatin in the therapy of familial dysbetalipoproteinaemia.

We studied the effects of ethinyl oestradiol on the serum concentrations and metabolism of very-low- and low-density lipoproteins (VLDL and LDL) in Watanabe heritable hyperlipidaemic (WHHL) homozygous rabbits, an animal model for familial hypercholesterolaemia. The results were compared with those in untreated homozygotes as well as in heterozygotes treated or not with ethinyl oestradiol. The gain in body weight was similar in all groups. Treatment with ethinyl oestradiol resulted in the homozygotes in an approx. 80% decrease in the concentrations of lipids and apoprotein B in the d less than 1.019 lipoprotein fraction; those in the LDL fraction did not change. In the heterozygotes, basal serum lipids and apoprotein B levels in the d less than 1.019 fraction were low; ethinyl oestradiol treatment especially affected the LDL fraction (cholesterol -84%, apoprotein B -64%). Turnover experiments with 125I-labelled VLDL revealed that, on treatment with ethinyl oestradiol, the fractional catabolic rate in homozygous rabbits increased 2-fold. The secretion rates of lipids and protein in the d less than 1.019 fraction as estimated after injection of Triton WR-1339 was not decreased. In homozygotes and heterozygotes increases in post-heparin hepatic lipase activity of 62 and 80% respectively were observed, with no changes in lipoprotein lipase activity. We conclude that ethinyl oestradiol induces in homozygous WHHL rabbits a direct removal of VLDL and VLDL remnants from the plasma, apparently due to an increase in hepatic lipase activity.

Forty patients with familial hypercholesterolaemia (FH) were treated with 40 mg pravastatin once daily. Pravastatin decreased serum total and low density lipoprotein cholesterol (LDL) after 8 weeks of treatment by 28% and 33%, respectively, while high density lipoprotein cholesterol increased by 8% and triglycerides decreased by 14%. In 30 patients LDL cholesterol had not decreased below 5.0 mmol l-1 after 8 weeks of treatment, and in these patients resins were added to pravastatin, resulting in an additional decrease in total and LDL cholesterol of 8% and 12%, respectively. A control group of 22 FH patients was treated with placebo for 10 weeks, after which time resins were added, and they induced a decrease in total and LDL-cholesterol of 17% and 22%, respectively. Our results over a 24-week treatment period indicate that 40 mg pravastatin is more effective than 3 packets of resins in lowering LDL cholesterol, whereas the combination is most effective of all and can be used safely.

In a group of 120 patients with heterozygous familial hypercholesterolemia (FH) the influence of the apolipoprotein E (apoE) polymorphism on pre-treatment plasma lipid levels and on the response to treatment with simvastatin was studied. The apoE phenotype distribution did not differ significantly between the FH group and a sample group of the Dutch population. Differences in pre-treatment lipid levels were not related to the apoE polymorphism in this FH population. After 12 weeks use of a daily dose of 40 mg simvastatin, the plasma total cholesterol, low density lipoprotein (LDL)-cholesterol and plasma triglyceride levels were reduced on average by 33%, 38% and 19%, respectively. At the same time high density lipoprotein (HDL)-cholesterol concentration increased on average by 7%. In the combined FH patient group (males and females) a considerable interindividual variation in response to simvastatin was observed, but was not related to the apoE polymorphism. However, considering males and females separately, we found that female FH patients with the apoE3E3 phenotype responded better on simvastatin treatment with respect to LDL-cholesterol than male FH patients with the apoE3E3 phenotype.

A 14-yr-old Turkish girl presented with serum cholesterol levels of 15-20 mmol/l, skin and tendon xanthomata, and anginal attacks. A coronary angiography demonstrated severe coronary atherosclerosis including a 70% stenosis at the origin of the left coronary artery. The clinical diagnosis, homozygous familial hypercholesterolaemia, was confirmed by: (1) investigation of the family revealing hypercholesterolaemia in both her parents and siblings; (2) fibroblast association studies, in which the specific association of low density lipoprotein (LDL) was 35% of normal; and (3) LDL turnover study, in which the fractional catabolic rate of LDL was decreased to 0.213 pools/day. Treatment with cholestyramine or simvastatin had little effect on serum cholesterol levels. After coronary artery bypass grafting, the patient was treated with selective LDL apheresis using columns containing dextran-sulphate bound to cellulose. These columns bind apolipoprotein B containing lipoproteins but not high density lipoproteins. After 2 yr of therapy, the level of serum cholesterol has declined by 56%. Skin xanthomata have disappeared and there is no recurrence of angina pectoris. On repeated coronary angiography, two of the three bypasses are patent and there is no progression of atherosclerotic lesions. We conclude that LDL apheresis is an efficient procedure to lower serum cholesterol in patients who do not respond to pharmacological treatment of hypercholesterolaemia.

The effects of simvastatin, an inhibitor of cholesterol synthesis, on serum lipids, lipoprotein composition and apolipoproteins were evaluated in a total of 50 patients with hypercholesterolaemia. In the first study, 24 patients (mean serum cholesterol 10.74 +/- 1.59 mmol/l) were treated with simvastatin 40 mg daily for 24 wk. Serum cholesterol and low density lipoprotein (LDL) cholesterol decreased to average values 29-36% and 35-42% below the basal value, respectively. Serum triglycerides decreased by 16-28%, and high density lipoprotein (HDL) cholesterol increased by 6-11%. Apolipoprotein A-I concentration increased 6-8% and that of apolipoprotein B decreased 29-33%. The composition of LDL remained unchanged whereas the very low density lipoproteins became enriched in triglycerides. Lipoprotein Lp(a) was not affected. In the second study 26 patients (mean serum cholesterol 12.35 +/- 2.05 mmol/l) were treated with simvastatin 40 mg daily as monotherapy or combined with a bile acid binding resin for 2 yr. Serum cholesterol levels decreased to values which remained stable throughout the entire study period; after 2 yr this decrease amounted to 43%. Compared to monotherapy, combination therapy yielded a further 12% decrease of cholesterol. In the entire group, triglycerides decreased by 16% and HDL cholesterol increased by 9%. Side effects were limited to slight increases in alanine aminotransferase and creatine phosphokinase in some patients. Simvastatin appears to be an important asset in the treatment of hypercholesterolaemia.

Purpose: Familial dysbetalipoproteinemia (type III hyperlipoproteinemia) is characterized by an increase of serum lipids caused by an accumulation of remnant particles of triglyceride-rich lipoproteins. We studied the efficacy of simvastatin, an inhibitor of the biosynthesis of cholesterol, in this disorder., Patients and Methods: Twelve patients participated in an open-label study. After a three-week placebo period, they were treated with increasing doses (10 mg twice a day, 20 mg twice a day, and 40 mg twice a day) of simvastatin in six-week periods., Results: With the 80-mg dose, the mean serum cholesterol level decreased from 12.30 +/- 4.96 to 5.29 +/- 1.24 mmol/L (mean reduction, 54%) and the mean serum triglyceride level decreased from 8.77 +/- 7.16 to 3.61 +/- 1.33 mmol/L (-48%); this was due to a decrease in very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) lipids. There was a decrease in the ratio of VLDL cholesterol to serum triglycerides and in the apolipoproteins B and E, suggesting a reduction in the amount of circulating atherogenic remnant particles. Except for a slight increase in serum alanine aminotransferase levels in three patients, no side effects were observed., Conclusion: These data show that levels of serum lipids can be effectively reduced by simvastatin in familial dysbetalipoproteinemia.

Simvastatin (MK-733), a new inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, was administered to 38 patients with heterozygous familial hypercholesterolaemia for 24 weeks. A dose of 40 mg per day produced a mean reduction in low density lipoprotein cholesterol of 43-45% and in triglycerides of 21-31%. Mean high density lipoprotein cholesterol increased significantly by 10-13%. There were no major differences in response whether the drug was taken in one or two doses. MK-733 was tolerated well. Adverse effects were infrequent and limited to slight increases of alanine aminotransferase, creatine phosphokinase and bilirubin. This drug appears to be a potent inhibitor of cholesterol synthesis and has produced the largest therapeutic response as monotherapy in patients with familial hypercholesterolaemia.

The effects of simvastatin, an inhibitor of cholesterol synthesis, was studied in 50 patients with hypercholesterolaemia. In the first study, 24 patients with serum cholesterol levels of 10.74 +/- 1.59 mmol/l were treated with simvastatin 40 mg daily for 6 months. Serum cholesterol levels decreased within 4 to 8 weeks to stable values 30 to 36% below the basal value. Serum triglycerides decreased by 16 to 28% and high density lipoprotein (HDL) cholesterol increased by 6 to 11% on average. In the second study, 26 patients with serum cholesterol levels of 12.35 +/- 2.05 mmol/l were treated with simvastatin 40 mg daily as monotherapy or combined with a bile acid binding resin for 2 years. Cholesterol levels decreased to values which remained stable throughout the entire study period; after 2 years the decrease amounted to 43%. Compared with monotherapy, combination with a bile acid binding resin yielded a further 12% decrease of cholesterol. In the entire group, triglycerides decreased by 16% and HDL cholesterol increased by 9% on the average. Side effects were limited to slight increases in alanine aminotransferase and creatine phosphokinase occurring in some patients. Simvastatin appears to be an important asset in the treatment of hypercholesterolaemia.

Two low-density lipoprotein subfractions, LDL-1 and LDL-2, with density ranges of respectively 1.023-1.034 and 1.036-1.041 g/ml, were isolated by aspiration after density gradient ultracentrifugation of human pooled serum. In vitro interactions of both LDL subfractions with the LDL receptor of human cultured fibroblasts, human hepatoma cell line Hep G2 and human hepatocytes were compared. No difference in association (binding and internalization) nor in degradation between LDL-1 and LDL-2 by these cells was found. However, kinetic studies in guinea pigs showed that LDL-2 disappeared faster from the circulation and accumulated to a greater extent in the liver, compared to LDL-1. Thus, we were unable to show a difference in the LDL receptor-mediated uptake of both LDL subfractions by various cells in vitro. The results obtained in vivo suggest that LDL-1 is more atherogenic than LDL-2, because its longer half-life renders the particle more susceptible to uptake by the scavenger LDL receptor on macrophages.

The effect of partial ileal bypass surgery (PIB) on lipoprotein concentrations and compositions and on the catabolism of low-density lipoproteins (LDL) was studied in Watanabe heritable hyperlipidemic (WHHL) rabbits. After PIB, total serum cholesterol was 65% lower (6.22 +/- 1.58 vs. 17.24 +/- 3.22 mmol/l) and LDL cholesterol 81% lower (2.02 +/- 0.95 vs. 10.90 +/- 3.60 mmol/l) than in control WHHL rabbits; cholesteryl esters, expressed as percentage of mass, were 55% lower in the very-low and intermediate-density lipoprotein (VLDL + IDL) fractions, and 45% lower in LDL, whereas triacylglycerols were 89% higher in VLDL + IDL and 121% higher in LDL. The fractional catabolic rate (FCR) of LDL protein (apoLDL) from operated animals was 10% higher than that from controls in all animals (0.55 +/- 0.10 vs. 0.50 +/- 0.10 pools/day; P less than 0.01). The FCR of autologous apoLDL in PIB rabbits was 50% higher than that of autologous apoLDL in control rabbits (0.63 +/- 0.05 vs. 0.42 +/- 0.06 pools/day); this was not caused by induction of receptor-mediated clearance of LDL. The production rate of apoLDL after PIB in PIB rabbits was 50% lower compared to control apoLDL in controls (26.0 +/- 6.7 vs. 51.7 +/- 16.4 mg/kg per day). We conclude that PIB lowers LDL cholesterol in WHHL rabbits by a decreased production of LDL, by an increased non-specific clearance of LDL and by compositional changes, which lead to LDL particles containing less cholesterol.

Simvastatin (MK733), derived from lovastatin by substituting CH3 for H at the 2' position, is a potent hydroxymethylglutaryl coenzyme A (HMG CoA) reductase inhibitor. Its cholesterol-lowering effect in 40 patients with heterozygous familial hypercholesterolaemia was more pronounced (an LDL-cholesterol reduction of 43%) than that of cholestyramine monotherapy in a matched group of 20 patients (30% reduction). The combination of the 2 drugs for 50 patients who tolerated cholestyramine was even more effective (a 54% reduction of LDL-cholesterol). The other changes were as follows: total cholesterol (simvastatin [S] -36%, cholestyramine [C] -23%, both drugs in combination [S + C] -45%); HDL-cholesterol (S +16%, C +9%, S + C +20%); triglyceride (S -21%, C +11%, S + C -17%); and the apolipoprotein B/apolipoprotein A ratio (S -51%, C -39%, S + C -67%). Cholestyramine caused more gastrointestinal adverse effects (12 of 20 patients), whereas a transaminase increase was seen both with cholestyramine (2 of 20 patients) and simvastatin (3 of 40 patients) and with the combination (6 of 50 patients). Treatment with simvastatin decreases the atherogenic potential of plasma more than cholestyramine monotherapy and causes fewer adverse effects. For those patients who tolerate cholestyramine, the combination of the drugs is even more potent.

Simvastatin, a derivative of lovastatin, is a potent inhibitor of cholesterol biosynthesis and may interfere with steroid hormone production, for which cholesterol is required. In a single-blind, placebo-controlled study, 24 patients with severe primary hypercholesterolaemia (mean serum cholesterol +/- SD = 10.74 +/- 1.59 mmol/l) were treated with simvastatin 40 mg per day for 8 weeks. Before and after treatment, the following parameters were evaluated: basal levels of ACTH, cortisol, androstenedione, dehydroepiandrosterone and 17-hydroxyprogesterone; urinary excretion of free cortisol; the cortisol response after short-term infusion of ACTH; the ACTH and cortisol response during insulin-induced hypoglycaemia. Total serum cholesterol decreased by 35.0 +/- 8.1% (P less than 0.001) and low-density lipoprotein (LDL) cholesterol by 39.8 +/- 9.8% (P less than 0.001); high-density lipoprotein (HDL) increased by 9.2 +/- 11.1% (P less than 0.001). Basal levels of ACTH were higher after simvastatin (2.9 +/- 1.9 pmol/l vs 4.1 +/- 2.9 pmol/l; P less than 0.05) whereas basal levels of steroid hormones were not significantly changed. The excretion of free cortisol was unaltered. The peak cortisol after ACTH infusion was lower after treatment (0.87 +/- 0.23 mumol/l vs 0.78 +/- 0.10 mumol/l; P less than 0.05), but was unaltered during insulin-induced hypoglycaemia. We conclude that simvastatin lowers serum cholesterol without clinically relevant effects on the adrenocortical steroid hormone secretion and the hypothalamic-pituitary-adrenal axis.