Effects of hypocholesterolemic dietary and drug therapy on measures of dysphoric emotions

The question of whether hypocholesterolemic treatment is associated with increased mortality due to suicide, violence and car accidents is controversial and of great importance. We investigated the effect of hypocholesterolemic dietary and drug therapy on dysphoric emotions. Twenty-five hypocholesterolemic men were started on a 3-month dietary modification plan; those who showed unsatisfactory cholesterol reduction were given, in addition, a hypocholesterolemic drug for up to 1 year. Lipid profile and change in dysphoric emotions were measured. During the whole period, a negative correlation was found between cholesterol level and depression. During the dietary period, a significant improvement in depression and guilt with no change in lipid profile was noted. Drug therapy significantly reduced cholesterol levels, with a trend toward increased depression (after 3 months) and a significant increase in aggression and guilt (after 1 year). We conclude that changes in dysphoric emotions occurring during hypocholesterolemic therapy cannot be completely explained by the changes in cholesterol levels.

Weight gain and insulin resistance during nicotine replacement therapy

BACKGROUND

Although the cessation of smoking reduces the increased risk for ischemic heart disease, it is associated with marked weight gain and presumably insulin resistance, both of which heighten the risk of coronary heart disease.

HYPOTHESIS

We investigated the isolated effect of nicotine on body weight and insulin resistance during smoking cessation.

METHODS

Eleven healthy, middle-aged heavy smokers were studied. Insulin sensitivity was assessed by an insulin-enhanced, frequently sampled intravenous glucose tolerance test with minimal model analysis. The subjects were studied at baseline (last day of smoking) (phase 1), at the end of the 6-week nicotine replacement program (phase 2), and after 8 weeks without smoking or nicotine replacement (phase 3).

RESULTS

The subjects started to gain weight during nicotine replacement (phase 2) (0.3 +/- 0.2 kg/week, mean +/- standard deviation) and continued to do so at a steady rate after nicotine replacement was stopped (0.2 +/- 0.2 kg/week) (p = 0.3). Insulin sensitivity decreased by 14 +/- 2.6% during nicotine replacement but increased by 16 +/- 5.1% (compared with phase 2) during phase 3, even though the weight gain continued (p = 0.047; 95% confidence interval: 0.05-5.73).

CONCLUSIONS

Smoking cessation is associated with weight gain and improvement in insulin resistance. Nicotine is the main ingredient in cigarette smoke causing insulin resistance, but the withdrawal of another, unknown ingredient in cigarette smoke is responsible for the weight gain associated with smoking cessation.

Serum homocysteine, folate, vitamin B12 levels and arterial stiffness in diabetic patients: which of them is really important in atherogenesis?

AIM

Hyperhomocystinaemia is associated with macro- and microangiopathic diabetic complications. However, the role of homocysteine (Hcy), serum folate, and vitamin B12 level in the development of premature vascular damage in type 2 diabetic patients is not clear. The present study was designed to assess the relationship between total Hcy, folate, and vitamin B12 levels and arterial stiffness, an early marker of generalized atherosclerosis.

METHODS

As many as 86 subjects with type 2 diabetes mellitus were studied. All participants were evaluated for glucose, HbA(1C), lipid profile, hs-CRP, endothelin, Hcy, vitamin B12, and folate. Pulse wave velocity (PWV) and augmentation index (AI) were performed as a non-invasive recording and computer analysis of the two artery sites pressure waveform using SphygmoCor (version 7.1, AtCor Medical, Sydney, Australia).

RESULTS

Hcy was significantly positively associated with age, serum creatinine, and vitamin B12 levels. No association between Hcy and folate was observed. The Hcy concentration was significantly positively associated with PWV (r = 0.540, p < 0.0001) and AI (r = 0.390, p < 0.0001). In a general linear model of PWV, Hcy emerged as an independent predictor of PWV even after controlling for age, creatinine, vitamin B12, and folate levels. In a multiple linear regression analysis, the association between Hcy and arterial stiffness was independent of traditional cardiovascular risk factors. Vitamin B12 levels were significantly inversely associated with tHcy (r = - 0.263, p = 0.015) and marginally associated with PWV(r = - 0.212, p = 0.052). Significant associations between folate levels and PWV were not detected.

CONCLUSIONS

The results lend support to the hypothesis that elevated Hcy may have a key role in the development of atherogenesis in diabetic patients. Additionally, vitamin B12 is significantly associated with tHcy concentrations and is identified as a marginally independent correlate of PWV in diabetic patients in the absence of folate deficiency.

Comparative Analysis Between Dextran Sulfate Adsorption and Direct Adsorption of Lipoproteins in their Capability to Reduce Erythrocyte Adhesiveness/Aggregation in the Peripheral Blood

The purpose of this study was to compare the degree of erythrocyte adhesiveness/aggregation (EAA) reduction of two low-density lipoprotein (LDL) apheretic procedures, namely direct adsorption of lipoproteins (DALI) and dextran sulfate adsorption (DSA). A significant (P < 0.001) reduction of EAA was noted in six hypercholesterolemic patients who underwent a total of 40 apheretic sessions and no difference was noted in the degree of EAA reduction by the two techniques. Thus. being a real-time and point-of-care test, the erythrocyte adhesiveness/aggregation test can be applied in relevant situations of acute ischemia, where therapeutic LDL apheresis could improve the hemorheology of individuals with increased concentrations of cholesterol and inflammatory sensitive proteins.

Significant dominance of fibrinogen over immunoglobulins, C-reactive protein, cholesterol and triglycerides in maintaining increased red blood cell adhesiveness/aggregation in the peripheral venous blood: a model in hypercholesterolaemic patients

BACKGROUND

It is not clear what is the relative importance of fibrinogen, immunoglobulins, highly sensitive C-reactive protein (hs-CRP), cholesterol and triglyceride concentrations on the appearance of aggregated red blood cells in the peripheral blood.

DESIGN

Six hypercholesterolaemic patients undergoing regular LDL apheresis that were examined repeatedly before and following the procedure.

RESULTS

We determined the degree of erythrocyte adhesiveness/aggregation in relation to the concentration of the above-mentioned macromolecules in 80 samples. In a linear logistic regression the respective R2 values for fibrinogen, total cholesterol, triglycerides, hs-CRP, IgG, IgM and IgA were 0.45 (P<0.0001), 0.2 (P<0.0001), 0.02 (P=0.02), 0.001 (P=NS) and 0.002 (P=NS), respectively. We further analyzed the potential of ApoA, ApoB and Lpa to participate in red cell adhesiveness/aggregation and found them to be not significant.

CONCLUSIONS

In a milieu of adhesive macromolecules, lipids and inflammation-sensitive proteins including fibrinogen, total cholesterol, triglycerides, hs-CRP and immunoglobins G, M and A, fibrinogen has a dominant role in maintaining the red blood cell adhesiveness/aggregation in the peripheral venous blood. These findings are relevant for the research directed at finding new apheretic modalities to reduce the degree of red blood cell adhesiveness/aggregation in the peripheral blood.

Insulin resistance in obesity: body-weight or energy balance?

Weight reduction is recommended for the treatment of subjects with insulin resistance (IR) syndrome; however, the relative importance of the decrease in body fat or the negative energy balance achieved during a hypo-energetic diet in the improvement of this metabolic syndrome is still debated. Therefore, we undertook to study their relative impact on amelioration of the metabolic abnormalities associated with IR in obese subjects. Twelve obese subjects (six males and six females, mean+/-s.d. body mass index 36.1+/-4.7 kg/m(2)) aged 38-57 years were investigated. During the first phase they were fed a hypo-energetic diet for 6 weeks (week 0-6). During the second phase, lasting 4 weeks (week 6-10) they consumed an iso-energetic diet. During the third phase (week 10-16) the subjects were put again on a hypo-energetic diet. Insulin sensitivity (SI) was assessed by an insulin-enhanced, frequently sampled i.v. glucose tolerance test with minimal model analysis. All subjects reduced weight during both hypo-energetic periods: 5.49+/-0.75 and 2.32+/-0.37%, means+/-s.e.m., P<0.005, week 0-6 and 10-16 respectively. One-third of this loss was achieved within the first week of each period. SI increased by 353+/-121 and 147+/-38% (P<0.005), means+/-s.e.m., at the end of both hypo-energetic periods (week 6 vs 0 and 16 vs 10 respectively). Two-thirds of this improvement were observed within the first week of each period (week 1 vs 0 and 11 vs 10 respectively). During the iso-energetic weight-maintaining period (week 10 vs 6), SI decreased by 43.5+/-7.9% (P<0.002). Serum levels of leptin and triglyceride followed a similar pattern, but to a lesser extent. It may be concluded that negative energy balance is more effective when compared with maintaining a stable lower weight in achieving an improvement in the metabolic parameters of the IR syndrome.

Pregnancy outcome in familial homozygous hypercholesterolemic females treated with long-term plasma exchange

BACKGROUND

The use of plasma-exchange therapy has increased the longevity of patients with homozygous familial hypercholesterolemia (HFH), and pregnancy in affected women is expected to become more common. We describe the clinical course, feasibility and risks of repeated pregnancies in patients with HFH treated by long-term plasma exchange.

METHODS

We followed the clinical course of five pregnancies in two HFH patients, with attention to the effect of repeated plasma exchange on maternal and fetal status; specifically, lipid profile, hemodynamics, and uteroplacental circulation on Doppler flow study.

RESULTS

Increasing the frequency of plasma-exchange therapy prevented the extreme serum cholesterol elevation that occurs in pregnant HFH patients and was associated with a significant improvement in uteroplacental circulation. In four pregnancies the clinical course was uneventful, ending in normal deliveries of full-term infants with heterozygous familial hypercholesterolemia. The third pregnancy of one of the patients had to be terminated owing to the development of hypotension and syncope during plasma exchange because of severe aortic stenosis.

CONCLUSIONS

Repeated pregnancies in HFH patients treated by long-term plasma exchange are feasible but may be associated with untoward effects, especially hemodynamic compromise. The frequency of plasma exchange therapy should be increased to prevent marked hypercholesterolemia and its possible deleterious effect on maternal and fetal status. Cardiac evaluation with close hemodynamic monitoring are needed during pregnancy to detect complications of the cardiac valvular lesion and the coronary atherosclerosis that are associated with HFH.

The effect of lovastatin on early restenosis

The effect of lovastatin given before percutaneous coronary angioplasty (PTCA) on early restenosis was investigated in men with mild to moderate hypercholesterolemia. Thirty-four hypercholesterolemic patients (serum LDL cholesterol 130-200 mg/dL) undergoing their first PTCA completed a 6-month prospective, double-blind, placebo-controlled trial. Eighteen received lovastatin 20 mg/day (Lo group) and 16 placebo (P1 group), beginning 10 to 21 days before PTCA. All underwent a thallium-201 quantitative exercise test 5 to 7 days after PTCA. Endpoints for restenosis were either 50% narrowing of the dilated artery on coronary angiography, performed in symptomatic patients or, in asymptomatic patients, the appearance of newly developed reversible filling defects in the vascular territory of the dilated artery on a second thallium scan done 6 months after PTCA. The hypocholesterolemic change observed in the Lo group was not accompanied by a reduction in early restenosis risk. The authors conclude that effective hypocholesterolemic therapy before PTCA does not affect early restenosis rate in men with mild to moderate hypercholesterolemia.

Efficacy and safety of pravastatin once daily in primary moderate hypercholesterolemia: the Israeli experience

Seventy-seven hypercholesterolemic patients participated in a 26-week, multicenter, randomized, double-blind, placebo-controlled study that investigated the efficacy and safety of pravastatin therapy. All patients had primary moderate hypercholesterolemia (total cholesterol 200-300 mg/dl, at the end of a 6-week dietary run-in period) and two additional coronary risk factors. Pravastatin, 20-40 mg/day given at bedtime, reduced total cholesterol by 19-22%, LDL-cholesterol by 24-30%, triglycerides by 10-30% and increased HDL-cholesterol by 9-13%. The drug caused mild elevation in alanine aminotransferase and aspartate aminotransferase. Almost all these elevations were within normal limits and no patient was clinically symptomatic. No other significant differences were observed between the pravastatin and the placebo-treated groups with regard to other adverse effects and to patient compliance and withdrawal. It is concluded that pravastatin has a beneficial effect on the lipid profile and that the drug is safe and well tolerated.

A missense mutation in the low density lipoprotein receptor gene causes familial hypercholesterolemia in Sephardic Jews

Familial hypercholesterolemia (FH) is an autosomal dominant disease caused by mutations in the low density lipoprotein (LDL) receptor gene. Here, we characterize an LDL receptor mutation that is associated with a distinct haplotype and that causes FH in the Jewish Sephardic population originating from Safed, a town in northern Israel. The mutation was found in eight FH families originating from this community comprising 10% of heterozygote FH index cases screened in Israel. The mutation was not found in four additional FH heterozygotes whose hypercholesterolemia co-segregated with an identical LDL receptor gene haplotype. A guanine to cytosine substitution results in a missense mutation (asp147 to his) in the fourth repeat of the binding domain encoded by exon 4 of the LDL receptor gene. The mutant receptor protein was synthesized in cultured cells as a 120 kDa precursor form that failed to undergo normal processing to a mature cell surface form. Most of the receptor precursors were degraded in the endoplasmic reticulum. The small number of mutant receptors on the cell surface were unable to bind LDL or beta very low density lipoprotein. The abnormal behavior of the mutant receptor was reproduced by site-directed mutagenesis and expression of the mutant protein in CHO cells. The mutation can be diagnosed by allele-specific oligonucleotide hybridization of polymerase chain reaction amplified DNA from FH patients.

Coronary risk factors in children of parents with premature coronary artery disease

In order to assess the value of family history of premature coronary artery disease as a criterion for coronary risk factor screening, a group of 53 children with such a family history was selected. We determined various coronary risk factors in these children in comparison to 33 controls. Statistically significant differences were observed in apoprotein concentrations but not in concentrations of lipids, lipoproteins or glucose, or in blood pressure or body mass index. The ratio between apoprotein B and apoprotein AI was the best discriminator between the two groups. The predictive value of family history is more reliable for detecting abnormal apoprotein ratio than for detection of hypercholesterolemia. We conclude that if abnormal apoprotein levels during childhood are found to be a valued predictor of premature coronary artery disease, then family history of premature coronary artery disease can be used to select children for determination and assessment of their coronary risk.

Big platelets in hyperlipidemic patients

Both "big" platelets and hyperlipidemia are associated with increased coronary risk. This study was undertaken to search for a possible effect of various hypolipidemic drugs on big platelets. The percentage of big platelets, assessed microscopically, was measured in 66 patients who had hyperlipidemia of various types. Twenty-seven patients with hypertriglyceridemia were randomly selected to receive either fish oil or placebo in a crossover study. Another group of 39 patients with hypercholesterolemia, among them 13 with heterozygous familial hypercholesterolemia (FH), received lovastatin. The pretreatment level of big platelets was elevated, and similar in all groups: 23.3 +/- 12% versus 22 +/- 9%, in the fish oil versus placebo group, 19.1 +/- 6.3% versus 24 +/- 11% in the FH versus non-FH primary hypercholesterolemia group (reference value, 6.8 +/- 3.5%). After treatment, despite the improvement in lipoprotein profile, the percentage of big platelets did not change. The relationship between lipid reduction and big platelets is thus questionable, and necessitates further study.

Lovastatin therapy in heterozygous familial hypercholesterolaemic patients: effect on blood rheology and fibrinogen levels

Thirteen heterozygous familial hypercholesterolaemic patients were treated with lovastatin for 1 year, and were investigated for the effect on lipid profile, blood rheology and fibrinogen levels. A significant dose-dependent reduction in serum levels of total and LDL-cholesterol, Apo B and the ratio of total cholesterol to HDL-cholesterol was noted. Improvement in red blood cell filterability and an increase in fibrinogen levels were also observed. We conclude that the hypocholesterolaemic effect of lovastatin in familial hypercholesterolaemia is accompanied by changes in blood rheology. While some of these haemorheological changes may be considered beneficial, others may be regarded as unfavourable. The net effect of lovastatin therapy on the coronary risk of familial hypercholesterolaemic patients warrants further investigation.

Lovastatin therapy in hypercholesterolemia: effect on fibrinogen, hemorrheologic parameters, platelet activity, and red blood cell morphology

The effect of lovastatin therapy on blood rheology was investigated in 26 hypercholesterolemic patients. Treatment with lovastatin was associated with a significant improvement in whole blood filtration time and a tendency toward normalization in red blood cell morphology. A significant increase was observed in fibrinogen level, in ADP-induced platelet aggregation, in the percentage of "big" platelets, and in platelet count. The viscosity of whole blood and plasma and the percentage of aggregated platelets did not change significantly. The cause for these hemorrheologic changes and their role in influencing the coronary risk of lovastatin-treated hypercholesterolemic patients should be further investigated.

Chylous ascites as a presenting sign of prostatic adenocarcinoma

Chylous ascites is usually associated with either primary disorders of the lymphatic system or malignancies of the lymph nodes such as Hodgkin and non-Hodgkin lymphoma. We describe, however, a young man in whom chylous ascites was a presenting sign of disseminated adenocarcinoma of the prostate gland. Most likely retroperitoneal lymph nodal replacement and tumor blockade of lymphatic collectors by metastatic adenocarcinoma was responsible for the development of chylous ascites.

Effects of fish-oil ingestion on cardiovascular risk factors in hyperlipidemic subjects in Israel: a randomized, double-blind crossover study

Effects of a daily fish-oil supplement on serum lipids, apolipoproteins, and some platelet functions and hemorheologic variables were examined in 27 hyperlipidemic subjects in a randomized, controlled, double-blind, crossover fashion with an identically encapsulated vegetable oil serving as the control treatment. Despite the habitual high linoleic acid intake of the study population, significant incorporation of n-3 (omega-3) fatty acids into the serum, platelet, and erythrocyte lipids was observed after the fish-oil supplement. Ingestion of fish oil resulted in a 40% decrease in the triglyceride concentration, a 12% increase in HDL cholesterol, and a significant decrease in plasma viscosity, whereas the vegetable-oil placebo had no significant effect. We conclude that a moderate intake of fish oil (15 g/d) is a feasible treatment for hypertriglyceridemia even in patients with a background of high linoleic acid intake and that it may have a beneficial effect on several cardiovascular risk factors.

The significance of paraproteinemia in hairy cell leukemia: case report and review of the literature

A case of hairy cell leukemia and IgG paraproteinemia is described. Peripheral blood surface marker analysis, serum paraprotein levels and immunoperoxidase stains of bone marrow sections at diagnosis and after 7 months of interferon treatment suggested the existence of two unrelated pathological B cell clones: one composed of malignant hairy cells and the other secreting the paraprotein. Previously reported cases of hairy cell leukemia with paraproteins are reviewed and our patient's contribution to the understanding of this association is stressed.

Pregnancy in a homozygous familial hypercholesterolemic patient treated with long-term plasma exchange

We describe the first pregnancy in a homozygous familial hypercholesterolemic woman who started plasma exchange therapy 3 years before she became pregnant. We especially studied the effects of plasma exchange on lipid profile, uteroplacental circulation, and pregnancy course.

Musculoskeletal manifestations in patients with hypercholesterolemia

Musculoskeletal symptoms were assessed in 33 patients with familial and 36 patients with nonfamilial type IIa hypercholesterolemia and compared to 33 healthy controls. Significant joint pain was reported by 47.8% of the patients with hypercholesterolemia vs 25.8% of the control group. Pain in the hyperlipidemic patients was significantly more prevalent in ankles and feet compared to the control group. The pain was not due to local effects of xanthoma, and was not accompanied by symptoms of inflammation or systemic rheumatic symptoms such as morning stiffness.

Hepatic infarction in a patient with the lupus anticoagulant

We describe a 31-year-old patient with missed abortion, thrombocytopenia, and clinical, laboratory, and radiologic evidence of hepatic infarction. On evaluation, she was found to have the lupus anticoagulant. The association between enhanced thrombosis and the lupus anticoagulant is discussed, and previously reported thrombotic complications are described. The etiology, clinical course, and radiologic features of liver infarction are summarized, and the importance of recognizing and treating this form of hypercoagulability is stressed. To our knowledge, this is the first description of liver infarction associated with the lupus anticoagulant.

Plasma metabolism of apolipoprotein A-IV in humans

As assessed by molecular sieve chromatography and quantitation by a specific radioimmunoassay, apoA-IV is associated in plasma with the triglyceride-rich lipoproteins, to a high density lipoprotein (HDL) subfraction of smaller size than HDL3, and to the plasma lipoprotein-free fraction (LFF). In this study, the turnover of apoA-IV associated to the triglyceride-rich lipoproteins, HDL and LFF was investigated in vivo in normal volunteers. Human apoA-IV isolated from the thoracic duct lymph chylomicrons was radioiodinated and incubated with plasma withdrawn from normal volunteers after a fatty meal. Radioiodinated apoA-IV-labeled triglyceride-rich lipoproteins, HDL, and LFF were then isolated by chromatography on an AcA 34 column. Shortly after the injection of the radioiodinated apoA-IV-labeled triglyceride-rich lipoproteins, most of the radioactivity could be recovered in the HDL and LFF column fractions. On the other hand, when radioiodinated apoA-IV-labeled HDL or LFF were injected, the radioactivity remained with the originally injected fractions at all times. The residence time in plasma of 125I-labeled apoA-IV, when injected in association with HDL or LFF, was 1.61 and 0.55 days, respectively. When 125I-labeled apoA-IV was injected as a free protein, the radioactivity distributed rapidly among the three plasma pools in proportion to their mass. The overall fractional catabolic rate of apoA-IV in plasma was measured in the three normal subjects and averaged 1.56 pools per day. The mean degradation rate of apoA-IV was 8.69 mg/kg X day. The results are consistent with the conclusions that: apoA-IV is present in human plasma in three distinct metabolic pools; apoA-IV associated with the triglyceride-rich lipoproteins is a precursor to the apoA-IV HDL and LFF pools; apoA-IV in LFF is not a free protein and its turnover rate is faster than that of apoA-IV in HDL; since no transfer of apoA-IV from the HDL or the LFF occurs, these pools may represent a terminal pathway for the catabolism of apoA-IV; and the catabolism of apoA-IV in HDL is dissociated from that of apoA-I although both apoproteins may reside on the same lipoprotein particles.

Plasma catabolism of human apolipoprotein E isoproteins: lack of conversion of the doubly sialylated form to the asialo form in plasma

Apolipoprotein E (apoE) circulates as a mixture of sialylated and asialylated forms. In this study the catabolic fate and the plasma turnover rate of the different apoE forms have been investigated in vivo in humans. Asialo apoE (E) and doubly sialylated apoE (Ess) were isolated by preparative isoelectrofocusing from the VLDL of subjects homozygous for the E3 allele. 131E3 and 125E3ss were injected simultaneously into three hypertriglyceridemic subjects, and plasma samples were collected up to the sixth day. VLDL were isolated by ultracentrifugation, and the apoE forms were separated by isoelectrofocusing. Gel bands corresponding to E3 and E3ss were cut out and counted for the associated radioactivity. Residence times in plasma for 131E3 and 125E3ss were 0.95 +/- 0.16 and 0.74 +/- 0.16 days, respectively. As determined from the gel count distribution up to 24 hours, no conversion of the injected sialylated form to the correspondent asialylated form was detected.

Urinary amine metabolite excretion in a patient with adrenergic hyperactivity state: reaction to phenelzine withdrawal and combined treatment

Urinary MHPG (3-methoxy-4-hydroxyphenylglycol) amounts increased threefold during a toxic delirious state in a 57-year-old bipolar patient 3 days after phenelzine treatment was stopped. This norepinephrine metabolite was not expected to rise as monoamine oxidase (MAO) was completely blocked. In addition, the delirious state appeared as a rebound phenomenon and not an acute toxic state during drug administration. It seems that phenelzine acts more through catecholamine release phenomenon than by inhibition of MAO.

The porphyrogenic effects of calcium channel blocking drugs

Treatment of monolayers of chick embryo hepatocytes with the calcium channel blocking drugs nifedipine and verapamil resulted in a decrease in the activity of uroporphyrinogen decarboxylase, an increase in the activity of delta-aminolaevulinate synthase and accumulation of porphyrins with uroporphyrin and heptacarboxylic porphyrin predominating. Diltiazem, another calcium channel blocking drug, did not affect uroporphyrinogen decarboxylase activity and had a slight effect only on the accumulation of porphyrins. Experiments with nifedipine and verapamil in the presence of various concentrations of calcium indicate that the porphyrogenic effect is apparently not related to blocking of calcium channels.

Impairment of induction of delta-aminolevulinic acid synthase by gluconeogenic amino acids and carbohydrates in vitro

This study was undertaken in a system of chick embryo liver cells incubated in Earle's Basal Salt Solution with hormones. Impairment of induction of delta-aminolevulinic acid synthase (ALAS) by allyl-isopropylacetamide (AIA) was observed in the presence of glucose. Fructose and various gluconeogenic substances including gluconeogenic amino acids had a similar effect. Leucine, which is purely ketogenic, did not influence induction of ALAS. SH-containing amino acids increased induction of ALAS by AIA. The glucose analogues 3-O-methylglucose and 2-deoxyglucose did not impair induction of ALAS by AIA. The inhibitory effect of glycerol, fructose, and glycine was not affected by 3-O-methylglucose but was reversed by 2-deoxyglucose. The results indicate that the salutary effects of proteins on acute attacks of hepatic porphyria are probably caused by their gluconeogenic properties and that glucose-6-phosphate, or metabolite of glucose-6-phosphate that is not in the glycolytic pathway, is the active agent that leads to the glucose-like effect.

Cholesterol turnover and metabolism in two patients with abetalipoproteinemia

Total body turnover of cholesterol was studied in two patients with abetalipoproteinemia, a 32-year-old man and a 31-year-old woman. The patients received [14C]cholesterol intravenously, and the resulting specific activity-time curves (for 40 and 30 weeks, respectively) were fitted with a three-pool model. Parameters were compared with those from studies of cholesterol turnover in 82 normal and hyperlipidemic subjects. A three-pool model gave the best fit for the abetalipoproteinemic patients, as well as for the 82 previously studied subjects, suggesting general applicability of this model. Cholesterol production rates in the two abetalipoproteinemic subjects (0.82 and 0.89 g/day) were close to values predicted for persons of their body weight. Thus, total body turnover rate of cholesterol was quite normal in abetalipoproteinemia, confirming previous reports. Very low values (9.2 and 8.4 g) were found for M1, the size of the rapidly exchanging compartment pool 1, in the two abetalipoproteinemic subjects. These values were well below the values predicted (from the comparison study population) for normal persons of this size with low plasma cholesterol levels. For one patient, total body exchangeable cholesterol was very low, although not significantly below the predicted values for a person of his size. In the second patient, the observed estimate for total body exchangeable cholesterol was well within the range of values predicted for persons of her size with low to extremely low cholesterol levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypocalcaemia, a possible manifestation of thyrotoxicosis

A severely thyrotoxic patient was found to have hypocalcaemia and tetany, which cleared when she became euthyroid. Cessation of treatment with propranolol and propylthiouracil resulted in a recurrence of the thyrotoxicosis and the reappearance of hypocalcaemia. Reinstitution of treatment resulted in a second remission of the thyrotoxicosis and correction of the hypocalcaemia. It is suggested that in this patient, the thyrotoxicosis was the cause of hypocalcaemia. The various pathogenetic mechanisms are discussed.

Eosinophilic pleural effusion with high anti-DNA activity as a manifestation of systemic lupus erythematosus

A patient, known to have systemic lupus erythematosus (SLE), presented with an eosinophilic pleural effusion. It is believed that SLE was the cause of her pleural effusion as increased levels of anti-DNA activity were found in the pleural fluid. Eosinophilic pleural effusion is a previosuly unreported observation in SLE patients (so far as the authors are aware), and the existence of increased anti-DNA activity in the pleural fluid may have value as an additional aid in the diagnosis of this disease.