Effect of Hyperlipidaemic Diet and Clofibrate Treatment on Rat Erythrocyte Lipids

Lipids of rat plasma and erythrocytes were analysed during hyperlipidaemic diet and clofibrate treatment. The diet increased the plasma cholesterol and phospholipid concentrations after 3 weeks' lipid feeding. Clofibrate in a dose of 200 mg/kg body weight did not inhibit the increase in plasma cholesterol and phospholipid contents, but significantly decreased the concentration of plasma triglycerides. The lipid diet slightly increased the erythrocyte cholesterol and phospholipid concentrations without affecting the red cell morphology or reticulocytosis. After 1 week's treatment, clofibrate in a dose of 200 mg/kg body weight caused a 2-fold increase in the cholesterol content and a rise in the cholesterol-phospholipid ratio of red blood cells of rats fed the hyperlipidaemic diet. These results suggest that the erythrocyte cell membrane can increase its cholesterol content and possibly play a role in cholesterol transport.     

Combined inhibitory effect of lactoferrin and lactoperoxidase system on the viability of Streptococcus mutans, serotype c

Abstract— We have studied the effects of iron-free lactoferrin (apo LF) and lactoperoxidase system (lactoperoxidase, LP/SCN^-/H₂O₂), separately and together, on the viability of Streptococcus mutans (serotype c) in vitro. The bacteria were incubated in buffered KCl (pH 5.5) with and without the above components which were used at concentrations normally present in human saliva. Both apo LF and LP-system had a bactericidal effect against S. mutans at low pH. Together they showed an additive, but not a synergistic, antibacterial effect against S. mutans . Apo LF enhanced the LP enzyme activity but decreased the yield of the antimicrobial component, hypothiocyanite (HOSCN/OSCN^-), when incorporated into the reaction mixtures. This decrease, which was most pronounced at low pH, was due to an LP-independent reaction between apo LF and HOSCN/OSCN^-. Our study indicates that the LP-system and apo LF can be combined to combat oral S. mutans .     

A five year follow-up study of attitudes to HIV infection among Finns

Changes from 1986 to 1990 in knowledge, attitudes and behaviouramong Finnish people towards HIV infection were studied. In1986, 1 013 Finns aged 15 to 64 years were chosen at randomfrom the entire population, and from 1987 to 1990 about 1 900annually were similarly selected. Interviews took place at homeor by telephone, using a structured questionnaire. Throughout the period knowledge was good about modes of HIVtransmission, as well as diagnostic methods and location oftest facilities. There appeared to be improvements over timein awareness about some aspects of transmission. Support forcompulsory population screening declined during the period,while the proportion in favour of voluntary testing grew. Opinionswere stable over the need for screening certain special groups.Perceptions of the personal threat of HIV also remained constantover the study years. There were no significant alterationsin sexual behaviour due to the risk of HIV infection. The study revealed that perceptions among Finns towards issuesof HIV infection did not change markedly between 1986 and 1990.Finnish opinions and attitudes relating to HIV infection maythus have stabilized.     

COMMENTS

Retinoblastoma family proteins pRb, p107 and p130 are differentially expressed in the rat testis. They function in specific cell types during testicular development and spermatogenesis, participating in the control of proliferation, differentiation, and survival. Their expression levels and phosphorylation status are modulated during germ cell cycle progression and apoptosis. Hyperphosphorylated states and elevated levels of p107 are correlated with cell cycle progression, whereas hypophosphorylated states and reduced levels are associated with suppression of proliferation and apoptosis in germ cells and Leydig cells. These proteins may also serve as markers of cell cycle status of germ cells during spermatogenesis.     

Habitual diet,platelet function,fibrinogen and facto VII coagulant activity in young Finns

Abstract. Objectives. The objective of the study was to determine whether an association between diet and platelet function, plasma fibrinogen level and factor VII coagulant activity (VII:C) could be established in young subjects. Design. Data on the habitual diet of the subjects were collected either by a questionnaire on food habits (n = 204) or by a 48-h dietary recall interview (n = 53). Subjects. The subjects were participants in the project ‘Cardiovascular Risk in Young Finns’ (age range 15–30 years). A total of 204 subjects having a questionnaire on food habits participated in the platelet function tests and 53 also participated in a 48-h dietary recall interview. Plasma fibrinogen concentration and factor VII: C were measured from 79 subjects. Main outcome measures. Platelet function was tested by turbidometric measurement of platelet aggregation using ADP and collagen as aggregation agents. Results. Platelet aggregation with ADP (at up to 4.0 μmol L^?1) and collagen (at up to 5.0 μg mL^?1 platelet-rich plasma PRP) showed that the diet characterized as ‘saturated’, i.e. containing high-fat milk and saturated fat, was associated with platelets less sensitive to aggregating agents in vitro when compared to the unsaturated type of diet. Collagen-but not ADP-induced aggregation decreased with age of the subjects (P = 0.026–0.057, regression coefficient). An inverse regression coefficient between plasma factor VII:C (101%; range 64–145%) and serum trigycerides (P = 0.006) and the intake of rye (g 1000 kcal^?1; P = 0.03) were found. Conclusions. In this study we showed that platelet reactivity and factor VII: C already differ considerably between subjects at a young age, and diet may explain some of this variation.     

Plasma renin substrate in the prediction of pregnancy outcome in threatened abortion

Summary. Concentrations of plasma renin substrate, serum oestradiol-17β, human chorionic gonadotrophin, sex-hormone binding globulin and plasma renin activity were measured in 77 samples from 74 patients with uterine bleeding during the first and second trimesters of pregnancy and in a control group of 29 normal pregnant women (51 samples). Mean concentrations of these substances were lower than control values in patients with an abnormal outcome of pregnancy. In patients with a normal outcome after uterine bleeding, concentrations were mostly within the control range. Serum oestradiol-17β concentration was superior to the other variables in predicting fetal outcome in the whole group. In patients with a live fetus at the time of blood sampling but who subsequently aborted, serum oestradiol-17β concentration was mostly normal, whereas plasma renin substrate was decreased. Our results suggest that plasma renin substrate may provide additional prognostic information to that given by serum oestradiol-17β measurement or ultrasonography in threatened abortion.