Importance of seafood as nutrient source in the diet of Belgian adolescents

BACKGROUND: Regular seafood consumption is recommended in dietary guidelines. The aim of this study was to investigate the importance of seafood as a nutrient source in adolescents' diet and the extent to which seafood consumption can increase the intake of omega-3 polyunsaturated fatty acids and vitamin D. METHODS: Consumption data recorded during seven consecutive days for 341 adolescents selected in Ghent (Belgium) were used to estimate the intake of vitamin D, linoleic (LA), alpha-linolenic (LNA), arachidonic (AA), eicosapentaenoic (EPA), docosapentaenoic (DPA) and docosahexaenoic (DHA) acid. RESULTS: The adolescents consumed on average 3.21 microg/day vitamin D, 11.7 g/day LA and 1.4 g/day LNA. The mean intakes of AA, EPA, DPA and DHA were 83.2, 55.9, 18.4 and 111.4 mg/day respectively. The major source of vitamin D was fortified margarine. Fats and oils were the main sources for LA and LNA. The intake of AA was mainly contributed by meat, poultry and eggs. Fish and seafood contributed for 84.1%, 59.3% and 64.4% respectively for EPA, DPA and DHA. CONCLUSION: Flemish adolescents would benefit from increased seafood consumption, as this would lead to a higher intake of EPA and DHA as well as of vitamin D. Moreover, replacement of foods rich in saturated fat (SFA) by seafood products can help to reduce SFA intake.     

Immunoadsorbent apheresis eliminates pathogenic IgG in childhood lupus nephritis

BACKGROUND: It is suggested that the highly cation-charged fraction of the IgG and IgG3 subclasses may play a pathogenic role in lupus nephritis. In contrast, immunoadsorbent therapy using a sodium dextransulfate fixed cellulose gel column-low invasive selective immunoadsorbent apheresis therapy (SDSC-IAT) has been applied to lupus nephritis with favorable results. However, elimination using pathogenic IgG by SDSC-IAT has never been investigated. METHOD: Two patients with diffuse proliferative lupus nephritis were treated using SDSC-IAT concomitant with immunosuppressive therapy. The eluates from the SDSC, and the patients' serum obtained before and just after SDSC-IAT were subjected to an IgG charge analysis using isoelectric focusing and immunoblotting, and also to laser nephelometry assay, which is used for measuring IgG subclass concentration. Indirect immunofluorescence staining was performed to detect IgG subclass deposition in the glomerulus. RESULTS: Both of the patients had an immediate decrease in anti-double-strand DNA antibody and in the circulating immune complex with a following clinical improvement. Repeated biopsies demonstrated improvement of glomerular lesions with a marked reduction of IgG and C3 deposition. The IgG of the SDSC eluates consisted of highly cation charged (isoelectric points: 9-10) fractions. In addition, IgG3 was specifically removed from the patients' serum using an SDSC among the IgG subclasses. The subclass of deposited IgG in the glomeruli showed IgG3 predominance. CONCLUSION: SDSC-IAT specifically removed the highly cation charged fractions of IgG and IgG3 from the patients' serum and the elimination of these fractions may have resulted in clinical improvement.     

The problem of rickets in UK Asians

A large body of work relating to the occurrence of rickets in UK Asians is reviewed. Several theories of the aetiology of this condition are shown to be untenable: it is not exclusively a function of sunlight deprivation or of darker pigmentation; nor is it simply due to phytate-induced losses of calcium from the gut. Asian rickets, however, is associated with a high consumption of cereals, and experiments with rats have suggested a mechanism. In the absence of adequate vitamin D from sunlight, the low-calcium, high cereal intake of the UK Asian population may induce a state of mild secondary hyperparathyroidism which enhances the destruction of vitamin D and leads to a progressive reduction in vitamin D status and, ultimately, to the development of clinical rickets.     

C_3基因在BXSB小鼠主要脏器中的表达

用同位素标记ｃＤＮＡ探针的分子杂交方法检测了ＢＸＳＢ小鼠肝、肾、脾、胸腺各脏器中补体Ｃ_３ｍＲＮＡ的表达情况，结果表明３～４月龄雄性ＢＸＳＢ小鼠肝、肾、脾各脏器Ｃ_３ｍＲＮＡ的表达量较正常对照鼠显著增加。Ｃ_３基因的过度表达可能参与ＢＸＳＢ小鼠ＳＬＥ多脏器非感染性炎症的发生，同时提示该鼠存在Ｍ系统的大量扩增及活化。     

Blockade of superoxide generation prevents high-affinity immunoglobulin E receptor-mediated release of allergic mediators by rat mast cell line and human basophils

BACKGROUND: Previous studies have shown that rat peritoneal mast cells and mast cell model rat basophilic leukaemia (RBL-2H3) cells generate intracellular reactive oxygen species (ROS) in response to antigen challenge. However, the physiological significance of the burst of ROS is poorly understood. OBJECTIVE: The present study was undertaken to investigate the role of superoxide anion in mediator release in rat and human cell systems. METHODS: RBL-2H3 cells were directly stimulated with anti-rat FcepsilonRI alpha-subunit monoclonal antibody (mAb). For the analysis of human cell system, leucocytes were isolated by dextran sedimentation from healthy volunteers or from patients, and challenged either with anti-human FcepsilonRI mAb or with the relevant antigens. Superoxide generation was determined by chemiluminescence-based methods. The releases of histamine and leukotrienes (LT)s were determined by enzyme-linked immunosorben assay (ELISA). RESULTS: Cross-linking of FcepsilonRI on RBL-2H3 cells or on human leucocytes from healthy donors by the anti-FcepsilonRI mAb resulted in a rapid generation of superoxide anion, as determined by chemiluminescence using superoxide-specific probes. Similarly, leucocytes from patients generated superoxide anion in response to the challenge with the relevant allergen but not with the irrelevant allergen. Furthermore, diphenyleneiodonium (DPI), a well-known inhibitor of flavoenzymes suppressed the superoxide generation and the release of histamine and LTC4 induced by the anti-FcepsilonRI mAb or by allergen in parallel. CONCLUSION: These results indicate that both RBL-2H3 cells and human basophils generate superoxide anion upon FcepsilonRI cross-linking either by antibody or by allergen challenge and that blockade of the generation prevents the release of allergic mediators. The findings strongly support the role of superoxide generation in the activation of mast cells and basophils under both physiological and pathological conditions. The findings suggest that drugs regulating the superoxide generation have potential therapeutic use for allergic disorders.     

Production and characterization of a new monoclonal antibody effective in recognizing the CD3 T-cell associated antigen in formalin-fixed embedded tissue

Phenotypic analysis of lymphoproliferative disorders is now considered mandatory for accurate classification which is the basis for optimum patient management. This is presently carried out in most cases using a range of antibodies recognizing B and T-cell antigens effective in paraffin sections, and an antibody to CD3 is currently a key member of such panels, indicating T-cell phenotype. Current antibodies to CD3 are polyclonal with the inherent disadvantages of this type of reagent compared to monoclonal antibodies. In this study, we have used a recombinant fusion protein representing part of the epsilon subunit of the CD3 molecule to generate a novel monoclonal antibody (NCL-CD3-PS1) effective in paraffin sections. The antibody has been characterized biochemically and by immunohistochemistry using a wide range of normal and pathological tissues. Lineage and phenotype specificity have been supported in our study and results from other laboratories are awaited with interest.     

Neurosteroid modulation of allopregnanolone and GABA effect on the GABA-A receptor

The neurosteroid allopregnanolone (ALLO) or 3α-OH-5α-pregnane-20-one interacts with the GABA type A receptor chloride ion channel complex and enhances the effect of GABA. Animal and human studies suggest that ALLO plays an important role in several disorders including premenstrual syndrome, anxiety, and memory impairment. In contrast to ALLO, steroids with a hydroxy group in the 3β position usually exert a reducing effect and have recently attracted interest due to their suggested role in counteracting the negative action of ALLO. In this study, five different 3β-steroids were tested for their ability to modulate GABA-mediated chloride ion uptake in the absence and presence of ALLO in rat brain microsacs preparations. In addition, the effects of the 3β-steroids and their interaction with ALLO were investigated by patch-clamp recordings of spontaneous inhibitory postsynaptic currents (sIPSCs) in rat hypothalamic neurons from the medial preoptic nucleus (MPN). All tested 3β-steroids reduced the ALLO-enhanced GABA response in cerebral cortex, in hippocampus and in MPN. In cerebellum, only one had this effect. However, in the absence of ALLO, two of the 3β-steroids potentiated GABA-evoked chloride ion uptake and prolonged the sIPSCs decay time, whereas the others had little or no effect. Therefore, it is possible that at least some 3β-steroids can act as positive GABA_A receptor modulators as well as negative modulators depending on whether or not ALLO is present. Finally, these results suggest that the 3β-steroids could be of interest as pharmacological agents that could counteract the negative effects of ALLO.     

Can supplementation of diet with omega-3 polyunsaturated fatty acids reduce coronary angioplasty restenosis rate?

The objective of this blinded, randomized, prospective study was to assess whether supplementation of normal diet with omega-3 polyunsaturated fatty acids can reduce angiographically defined restenosis following coronary angioplasty. The study included all patients undergoing coronary angioplasty in this institution between January 1988 and January 1989. One hundred and twenty patients enrolled, 60 in each treatment group. All were randomized to either supplementation of normal diet with 3 g of omega-3 polyunsaturated fatty acids per day started 1-2 days prior to angioplasty and continued for 6 months (treatment group), or to receive standard therapy only (control group). Quantitative angiographically defined restenosis was assessed at 6 months post angioplasty. Restenosis occurred in 27.8% (95% CI 18.0-37.7%) of lesions in the treatment group and in 28.3% (CI 16.9-39.7%) of lesions in the control group, but the difference was not statistically significant. The study showed that diet supplemented with 3 g of omega-3 polyunsaturated fatty acids started 1-2 days preceding angioplasty does not reduce angiographically defined restenosis rate.     

Calorie restriction increases serum parathyroid hormone and decreases serum calcitonin levels in patients with maturity onset diabetes mellitus

Calorie restriction is important in managing patients with maturity onset diabetes mellitus (NIDDM). The effect of such restriction on calcium metabolism is not known. The objective of this study was to determine whether patients on calorie restricted diets would show any modification of parathyroid hormone (PTH) and calcitonin (CTN). The serum levels of PTH and CTN were measured by radioimmunoassays in 269 patients with NIDDM. The patients were divided into two groups depending on the intake of calorie, and PTH and CTN were monitored for 2 years. Plasma levels of vitamin D were measured by competitive protein binding assays before and after each program. The level of PTH (520.8±266.0 pg/ml) (mean±S.D.) was significantly (P<0.01) higher in 109 diabetic patients whose calorie intake was restricted for 2 years (diet (D) group) as compared with that (256.6±103.8 pg/ml) of 160 diabetic patients whose calorie intake was not restricted (non-diet (ND) group). The daily oral calcium intake of the two groups did not differ significantly. We found no significant difference in the serum PTH level in the ND groupVS. normal control subjects (248.8±98.4, N=78). The serum calcium concentration and the amount of calcium excreted in urine were slightly but significantly (P<0.01) lower in the D than in the ND group. The rate of tubular reabsorption of phosphate (% TRP) was significantly lower in the D group than that in the ND group (P<0.01). The serum CTN level was significantly (P<0.01) lower in the D group (33.9±11.3 pg/ml) than in the ND group (64.9±21.2 pg/ml) 2 years after each treatment. The plasma 1,25-(OH)₂-vitamin D level was significantly (P<0.01) lower in the D group (22.2±6.6 pg/ml) than in the ND group (50.6±4.2 pg/ml). When the restriction of calorie intake in the D group was canceled, their PTH levels decreased, which was accompanied by increase in the 1,25-(OH)₂-vitamin D levels, whereas their CTN levels were unchanged. These observations suggested that a restricted calorie intake is a risk factor for secondary hyperparathyroidism as well as for a low serum level of CTN in patients with NIDDM.