The effects of dietary N-3 and antioxidant supplementation on erythrocyte membrane fatty acid composition and fluidity in exercising horses

REASONS FOR PERFORMING STUDY

Fatty acid supplementation could modulate erythrocyte membrane fluidity in horses at rest and during exercise, but information is lacking on the effect of exercise.

OBJECTIVES

To assess the effect of exercise with, and without, an oral antioxidant supplementation enriched with n-3 fatty acids on erythrocyte membrane fluidity (EMF) and fatty acid composition in eventing horses.

METHODS

Twelve healthy and regularly trained horses were divided randomly into 2 groups: group S received an oral antioxidant cocktail enriched in n-3 fatty acid (alphatocopherol, eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) whereas group P was placebo-treated. At the end of 4 weeks, all horses performed a standardised exercise test (ET) under field conditions. Venous blood was sampled before starting treatment (TO), immediately before (T1) as well as 15 min (T2) and 24 h (T3) after ET. Spin labelled (16-DOXYL-stearic acid) red blood cell membranes were characterised using the relaxation correlation time (Tc in inverse proportion to EMF). Fatty acid composition (%) of the membrane was determined by gas-liquid chromatography.

RESULTS

Supplementation did not induce changes in EMF (T1 vs. TO) but significant changes in membrane composition were observed and there were increases in n-3 polyunsaturated fatty acid PUFA, n-3/n-6 ratio, and total n-3 fatty acids. Exercise (T2 vs. T1) induced a significant decrease of EMF in group P (Tc: +19%, P<0.05) and nonsignificant decrease in group S (Tc: +5%), whereas membrane fatty acid composition did not change in either group. During the recovery period (T3 vs. T2), EMF decreased significantly in group S (Tc: +29%, P<0.05) and nonsignificantly in group P (Tc: +18%) without any significant changes in fatty acid composition.

CONCLUSION AND POTENTIAL RELEVANCE

An enriched oral antioxidant supplementation induced changes in membrane composition, which modulated the decrease in EMF induced by exercise. Long chain n-3 fatty acid supplementation might therefore be beneficial.

Effect of treatment on biclonal gammopathy associated with Gaucher disease

The non-random association of Gaucher disease with polyclonal and monoclonal gammopathy has been known since 1950. The effect of treatment on monoclonal gammopathy is not well documented. We report on the long-term evolution of a biclonal gammopathy in a patient with type I Gaucher disease who was treated with splenectomy and enzyme replacement therapy. A 44-year-old man presented with hepatomegaly and massive splenomegaly. Bone marrow aspirate contained typical Gaucher cells and beta-glucosidase was low in peripheral blood leukocytes. Mutations N370S and R120W were detected. Serum protein electrophoresis disclosed two spikes in gammaglobulins. Immunofixation identified two monoclonal components: IgG kappa and IgA kappa. Gammaglobulin concentration was 31.6 g/L. A splenectomy was performed on September 2003 because of massive splenomegaly (9500 g). Two months after the splenectomy, gammaglobulin concentration was 25.2 g/L. Enzyme replacement therapy (Cerezyme 45 UI/kg every two weeks) was prescribed from April 2004 because of significant hepatomegaly and cholestasis. In April 2007 (3 years after the beginning of treatment), serum electrophoresis showed the persistence of two spikes with gammaglobulin concentration at 20.5 g/L. Simultaneously, chitotriosidase activity decreased from 6181 to 2877 nkat/L. Our observation and previous reports suggest that enzyme replacement therapy is more effective in polyclonal hypergammaglobulinaemia than in monoclonal gammopathy.

[Epidemiology of monoclonal gammopathy in a general hospital and a university internal medicine department]

PURPOSE

Monoclonal gammopathy are common in the general population. We describe biological features and etiology of monoclonal gammopathy diagnosed during more than a ten year period in the Internal Medicine Department of Rennes University Hospital and in all the medical departments of General Hospital of Blois.

METHODS

Patients were identified by immunofixation registry of Biochemistry Laboratories in both hospital (from 1990 in Rennes and from 1980 in Blois).

RESULTS

Internal Medicine Department of Rennes University Hospital: 1051 monoclonal gammapathies were identified: 514 men and 537 women. Median age was 71. Isotypes repartition was: IgG 42.8% (450 cases), IgM 31.9% (335), IgA 8.9% (94) biclonal gammopathy 9.8% (103). Sixty-nine monoclonal light chains (6.6%) were identified. Median concentration of monoclonal protein was 14 g/l (1.8-104.4). All department of General Hospital of Blois: 1282 monoclonal gammapathies were identified: 700 men and 582 women. Median age was 79. Isotypes repartition was: IgG 59.7% (765 cases), IgM 27.5% (329), IgA 11.8% (151). Thirty-four monoclonal light chains (2.7%) were identified. Median concentration of monoclonal protein was 5.6 g/l (0.5-96.6). Most frequent diagnosis were: monoclonal gammopathy of undetermined significance or MGUS (77.6% in Blois and 64.1% in Rennes), multiple myeloma (11.9% and 12.7%), Waldenström's macroglobulinemia (4.4% and 8.7%).

CONCLUSION

Monoclonal gammopathy are common in clinical practice. MGUS account for more than 60% of monoclonal gammopathy. Given their frequency, diagnostic and follow-up strategies must be costless and simple.

Caractéristiques des fumeurs s’adressant aux consultations de tabacologie

INTRODUCTION

The development of smoking cessation clinics in France since 1999 has been accompanied by the setting up of an electronic database to evaluate the appropriateness of these services to the needs of smokers. The aim of this paper is to analyse the characteristics of smokers registered in the smoking cessation services national database.

METHODS

A cross-sectional population-based study was conducted in 40 smoking cessation centres from 20 French regions. The study population included 14,574 smokers attending the smoking cessation centres that participated in building a national computerised database during the period 2001-2003.

RESULTS

A significant proportion of the study population was female (51.4%), middle-aged (42.8 years), more highly educated (34% had received further education) and employed (68%). Almost half of the population was considered to be highly dependent on tobacco. Thirty-four percent of smokers had a past medical history of cardiovascular or lung disease. A history of depression was found in nearly one third of the population.

CONCLUSIONS

Young people and individuals from deprived backgrounds were underrepresented, but smoking cessation services were being accessed by highly-dependent smokers and smokers with tobacco-related diseases services. More targeted smoking cessation strategies should be considered in order to improve access to smoking cessation services by more deprived groups.

Postprandial variations in the cholesteryl ester transfer protein activity, phospholipid transfer protein activity and plasma cholesterol efflux capacity in normolipidemic men

BACKGROUND AND AIM

Plasma cholesterol efflux capacity is stimulated during postprandial (PP) hypertriglycerdemia. Plasma cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) are the key proteins in lipoprotein metabolism and remodelling, but their role during the PP cholesterol efflux process remains indeterminate. The aim of this study was to determine the effect of a fatty meal intake on plasma CETP and PLTP activities, and the capacity of plasma to promote cholesterol efflux, as well as to evaluate the relationship between these three key mechanisms of the reverse cholesterol transport process.

METHODS AND RESULTS

CETP and PLTP activities and the cholesterol efflux capacity of plasma were measured over eight hours following a fatty meal (1000 kcal, 62% fat) in 13 normolipidemic men. CETP activity and the cholesterol efflux capacity of plasma from Fu5AH cells increased after the meal, reaching a maximum after eight hours (respectively 32%, p = 0.06, and 6.5%, p = 0.045), whereas PLTP activity remained unchanged. CETP and PLTP activities did not correlate with plasma cholesterol efflux capacity in the fasting or PP state. Plasma CETP activity in the fasting state positively correlated with the plasma non-esterified fatty acid (NEFA) levels, but no correlation was found with any lipid or apolipoprotein postprandially. The cholesterol efflux capacity of plasma correlated positively with high-density lipoprotein (HDL) components, the best correlation being with the HDL phospholipid fraction in both the fasting and PP states.

CONCLUSIONS

These findings suggest that plasma CETP and PLTP activities in healthy normolipidemic subjects are differently regulated in the PP state, and are not correlated with the increased cholesterol efflux capacity of PP plasma. HDL-phospholipid remains the key factor in the regulation of the capacity of plasma to promote Fu5AH cell cholesterol efflux.

Serum paraoxonase activity and paraoxonase gene polymorphism in type 2 diabetic patients with or without vascular complications

BACKGROUND

Serum paraoxonase (PON) activity and the relevance of PON gene polymorphism in vascular complications of type 2 diabetic patients were investigated in a case-control study.

METHODS

The population included 105 control subjects, 96 diabetic patients without vascular complications and 71 diabetics with vascular complications.

RESULTS

Serum PON activity was significantly decreased (p<0.001) in diabetic patients without vascular complications: 207 IU (25-817) compared with the controls: 259 IU (24-950). Although serum PON activity was also decreased: 232 IU (34-797) in the population with vascular complications, the difference was not statistically significant (p=0.11). The Q192 allele frequency is significantly higher (p<0.005) in diabetics without vascular complications (77%), and with vascular complications (73%) than in the controls (63%). No significant association was found between either PON(1)55 L/M and PON(2)311 C/S gene polymorphisms and vascular complications.

CONCLUSIONS

The difference in allele frequency for the PON(1) Q/R 192 gene polymorphism may be the cause of the low paraoxonase activity observed in type 2 diabetes mellitus. Further studies need to be conducted to elucidate the role of the enzyme in the development of vascular complications in diabetes.

Determination of lipoprotein(a) concentrations and apolipoprotein(a) molecular weights in diabetic patients

Lipoprotein(a) (Lp(a)) with atherogenic and thrombotic properties has been frequently studied in diabetes, because a high cardiovascular risk has been reported both in type 1 and type 2 diabetes. Few studies have considered genetic factors, especially the isoforms of apolipoprotein(a). The aim of this work is to determine the distribution of apo(a) phenotypes in the serum of 148 diabetic patients (59 type 1, 89 type 2) with or without vascular complications. Apo(a) phenotypes are determined using 4-15% sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by immunoblotting (PhastSystem - Pharmacia). An inverse relationship is observed between Lp(a) serum concentration and the apparent molecular mass of apo(a) isoforms: type 1 r=- 0.61, p<0.01; type 2 r=- 0.55, p<0.01. The frequency of apo(a) isoforms is significantly different between type 1 and type 2 diabetes mellitus. A higher prevalence of isoforms of low molecular weight was observed in the type 2 diabetic population.

Models to predict cardiovascular risk: comparison of CART, multilayer perceptron and logistic regression

The estimate of a multivariate risk is now required in guidelines for cardiovascular prevention. Limitations of existing statistical risk models lead to explore machine-learning methods. This study evaluates the implementation and performance of a decision tree (CART) and a multilayer perceptron (MLP) to predict cardiovascular risk from real data. The study population was randomly splitted in a learning set (n = 10,296) and a test set (n = 5,148). CART and the MLP were implemented at their best performance on the learning set and applied on the test set and compared to a logistic model. Implementation, explicative and discriminative performance criteria are considered, based on ROC analysis. Areas under ROC curves and their 95% confidence interval are 0.78 (0.75-0.81), 0.78 (0.75-0.80) and 0.76 (0.73-0.79) respectively for logistic regression, MLP and CART. Given their implementation and explicative characteristics, these methods can complement existing statistical models and contribute to the interpretation of risk.

[Multicenter evaluation on different analyzers of three methods for direct HDL-cholesterol assay]

Most frequently, in routine laboratories, C-HDL is measured in the supernatant after precipitation of apolipoprotein B-containing lipoproteins by the sodium phosphotungstate/magnesium chloride reagent (PTA). This method involves precipitation, centrifugation and decantation steps which prevent full automation of the measurement and decrease the accuracy of the results. Recently, three direct assays for C-HDL including alpha-cyclodextrin sulphate (alpha-CD), polyanions/detergents (PA-D) or antibodies anti-beta-lipoproteins (AC) have been commercialized, in which all steps are fully managed by automated analyzers. These new methods have been compared to the conventional procedure (PTA), in multicenter studies among six laboratories using different analyzers. The C-HDL values measured by the alpha-CD and PA-D assays correlated well with those of the PTA method (r > 0.98), on most of the analyzers. With the AC assay, only the results obtained with the Hitachi 717 analyzer were correlated with C-HDL values of the PTA method. The linearity and specificity studies were evaluated in the laboratory A on a Kone Specific analyzer. The alpha-CD and PA-D assays were linear for C-HDL values from 0 to 5.56 mmol/l, as observed by increasing amounts of HDL2 + HDL3 or serum without lipoprotein isolated by ultracentrifugation. The specificity of these two methods was evaluated simultaneously, by adding various amounts of lipoproteins isolated by sequential ultracentrifugation. No interference was observed when adding chylomicrons up to 13.4 mmol/l of triglycerides for both methods. Inversely, increased C-HDL values were observed with added VLDL from 6 mmol/l of triglycerides for the PA-D assay and from 8 mmol/l for the alpha-CD assay. No interference was observed with added LDL up to 11.5 mmol/l of C-LDL for the alpha-CD assay and up to 6.7 mmol/l for the PA-D assay. In conclusion, the present multicenter evaluation demonstrates that the new procedures for the direct automation of C-HDL are easy and accurate and most of them correlated well with the classical precipitation method. In addition the study provides arguments for a choice between the different direct C-HDL methods.

[Triclonal gammopathy and malignant immunoproliferative syndrome]

Three distinct monoclonal gammopathies were identified in the serum of a 79 year-old man. In 1972 he presented with Waldenström's macroglobulinemia IgM Kappa. Twenty years later multiple myeloma was diagnoses. Serum protein electrophoresis performed at this time showed three monoclonal bands. Immunofixation identified these bands as monoclonal IgM kappa, IgG kappa and IgA kappa. Twenty-six cases of triclonal gammopathies were previously reported. Sixteen cases were associated with malignant immuno-proliferative diseases (non-hodgkin lymphoma, Waldenström's macroglobulinemia, multiple myeloma); five cases with non-hematologic diseases; three cases were of undetermined significance. The origin of three distinct monoclonal proteins may derive from three unrelated clones or alternatively from a single clone in which an isotype switch has occurred.

Fortuitous diagnosis of the association of hemoglobin J-Broussais with beta + thalassemia

The authors report a case, not described so far in literature, of an association of HbJ-Broussais [alpha (90 (PG2) lys-->asn beta 2] with beta + thalassemia in a young girl born of Italian father and Breton mother. This association is clinically silent. Biochemistry revealed, besides HbA, the presence of HbJ-Broussais in the proportion of 19.4% and HbA2 value of 3.9%. These percentages, slightly lower than expected, are explained. A familial study is presented.

Serum lipid, apolipoprotein and lipoparticle levels in the human fetus

Blood collected from 62 fetuses aged 20-38 weeks of gestation was studied. The values of ten lipid parameters were determined: cholesterol (TC), triglycerides (TGs), apolipoprotein A1 (apo A1), apolipoprotein B (apo B), apolipoprotein E (apo E), total apolipoprotein CIII (apo CIII), apolipoprotein CIII present in particles containing apo B (apo CIII LpB) or not (apo CIII Lp non-B), lipoparticles A1 (LpA1), and lipoprotein a (Lp(a)). The results show that, except for apo E, all the studied parameters were present in lower concentrations than in adults and newborns, and that Lp(a) is not detectable at that stage in life.

Increase in thiobarbituric acid-reactive substances and vascular complications in type 2 diabetes mellitus

Lipid peroxidation was assessed by measuring the concentrations of thiobarbituric acid-reactive substances in plasma from 204 Type 2 diabetic patients, relative to 107 controls. The concentrations obtained in diabetic patients (3.08 +/- 0.37 mumol/l) were significantly higher than in controls (2.80 +/- 0.34 mumol/l) (p < 0.0001). Values were also significantly increased in patients with macroangiopathy and/or microangiopathy (3.17 +/- 0.41 mumol/l), relative to patients void of vascular complications (2.92 +/- 0.34 mumol/l) (p < 0.001). Elevated concentrations were independent of the type of vascular complication and their possible associations. In patients without vascular affection, thiobarbituric acid-reactive substances were in significantly higher concentrations in hypertensive (3.07 +/- 0.36 mumol/l) than in normotensive (2.87 +/- 0.29 mumol/l) (p < 0.01) patients. There was a correlation between these values and those of total cholesterol (r = 0.46, p < 0.0001) and triglyceride (r = 0.45, p < 0.0001). Statistical analysis by multivariate logistical regression revealed that among the independent factors (TBARS, APO A1, hypertension, age), thiobarbituric acid-reactive substances constituted the parameter most strongly linked to the existence of vascular complications. This study has evidenced a lipid peroxidation disorder in non insulin- dependent diabetes mellitus, more marked in patients with vascular affection. Thiobarbituric acid-reactive substances appear to be an independent marker of vascular complications in Type 2 diabetes.

LDL sialic acid content in patients with coronary artery disease

Low density lipoproteins (LDL) are considered to be the most atherogenic of lipoproteins. These LDL can be modified and oxidative modifications are now well known. In addition, other atherogenic modifications of LDL exist, such as desialylation. In the present study sialic acid content was determined in LDL preparations obtained from patients with coronary artery disease (CAD+) and compared with that of healthy subjects and patients without coronary heart disease (CAD-). The sialic acid concentration was found to be statistically lower (P < 0.05) in the LDL of CAD+ patients (11.6 +/- 2.7 micrograms/mg of protein) than in the LDL of controls (16.5 +/- 5.6 micrograms/mg of protein) or in the LDL of CAD- patients (15.3 +/- 3.8 micrograms/mg of protein). In subgroups of CAD+ patients divided according to the severity of the disease, no statistically significant difference was observed in LDL sialic acid content. This work confirms the presence of desialylated LDL in the sera of patients with atheroma.

Plasma malondialdehyde in type 1 and type 2 diabetic patients

Malondialdehyde, a marker of lipid peroxidation, was measured as thiobarbituric acid reactive substances (TBARS) in 117 diabetic patients and 53 controls. Patients were divided into groups and subgroups according to the type of diabetes (type 1 and type 2) and the existence or not of vascular complication (macro- or micro-angiopathy). Results showed that TBARS concentrations were significantly higher in type 1 (P < 0.0001) and type 2 (P < 0.001) diabetic patients than in the control group. The plasma TBARS concentrations in type 1 and type 2 diabetic patients did not differ significantly. Among the patients with vascular disease, type 2 diabetic patients with macroangiopathy had significantly higher TBARS concentrations than patients with no vascular complication (P < 0.05). Whichever the type of diabetes, there was no correlation between TBARS concentrations and glycaemic control: glycosylated haemoglobin, fasting blood glucose. This study confirmed the existence of lipid peroxidation disorders in diabetic patients.

[Identification of a type 1 macrocreatine kinase]

A macrocreatine-kinase type 1 was identified by CK isoenzyme electrophoresis of a serum sample from a patient. Constituents of this enzyme complex were studied. The isoenzyme present in the macrocreatine-kinase was identified using immunoprecipitation with antibodies against the M subunit. Affinity chromatography then determined the type of the immunoglobulin bound to the CK isoenzyme. A protocol for studying macrocreatine-kinase type 1 compounds is proposed.

Blood chemistry of human fetuses in the second and third trimesters

Six biochemical parameters and four enzyme activities were determined from the serum of 76 healthy and 56 pathological human fetuses between the 20th and 38th week of pregnancy. In the normal fetuses studied within that period, creatinine, immunoglobulin M, lactate dehydrogenase, and gamma-glutamyltransferase increased; haemoglobin F and glucose progressively decreased; and alkaline phosphatase was at a peak around the 26th week; cholesterol and triglycerides were always low. The same parameters were also measured in some of the pathological fetuses and compared with their normal counterparts.

Cutaneous interstitial fluid protein concentrations in the inflammatory syndrome: pharmacological consequences

Concentrations of alpha 1 acid glycoprotein, albumin, transferrin, haptoglobin, immunoglobulins G, A, M and apolipoprotein B were measured in serum and suction blister fluid from a group of individuals presenting a biologically proven inflammatory syndrome, and from a control group. Protein values in suction blister fluid did not change from the 2nd to the 3rd h after the beginning of blister formation. The ratio of the concentration of proteins in blister fluid and serum did not differ significantly between the groups. However, a 25% decrease in blister fluid albumin and a 100% increase in blister fluid alpha 1 acid glycoprotein, recorded in the inflammatory group, were worth noting, since they possibly influence the tissular distribution of some protein-binding drugs. Finally, an inverse relationship was established between the blister fluid/serum concentration ratio and the respective molar mass of each protein.

Level of plasma fibronectin in patients with breast cancer

Plasma fibronectin was determined by laser nephelometric immunoassay in two populations: healthy individuals and patients with metastatic or non-metastatic breast cancer. The results showed that the fibronectin concentration was higher in the patient group than in the healthy controls of similar age, with a significant difference (p less than 0.05). The patients who had metastatic breast cancer tended to show higher levels than those with no detectable metastasis, but such a difference was not statistically significant. Since fibronectin is sensitive to clinical events unrelated to the malignancy status, it does not seem suitable as a tumor marker.

[Use of monoclonal antibodies for the immunoenzymological determination of alpha-fetoprotein in amniotic fluid]

A two site immunoenzymatic assay using monoclonal antibodies for alpha-fetoprotein in amniotic fluid has been evaluated. Results obtained with monoclonal antibodies correlated well with those obtained by electroimmunodiffusion assay. The evaluation of this method has shown rapidity, accuracy and a better sensitivity than electroimmunodiffusion assay. Further more the measurements of both maternal serum and amniotic fluid alpha-fetoprotein can be associated.

[Use of monoclonal antibodies for the immunoenzyme determination of creatine kinase-isoenzyme MB]

An enzyme immunoassay using monoclonal antibodies for creatine kinase-MB in human serum is described. The specificity and the linearity have been studied. The coefficient of within assay ranges from 6% to 22.5% according to the concentrations. The coefficient of between-assay ranges from 8% to 16.6%. Compared to electrophoresis, the results obtained with the enzyme immunoassay are a better sign of the physical state of the patients.

Synthesis and phosphorylation of cytoskeleton components in foetal, regenerating and adult normal rat hepatocytes during culture

Detergent insoluble material (DIM) was prepared by gentle treatment with detergent from foetal, regenerating and adult normal rat hepatocytes cultured for various times. It retained to some degree the morphology of the cells. After incubation of intact cells with 35S-methionine, most of the labelled DIM proteins were found to be components of the cytoskeleton. They included several cytokeratins, vimentin and actin. The synthesis rate varied with the age of animals and culture conditions. The high synthetic rate of vimentin in foetal and regenerating hepatocytes could be associated with cell proliferation. No correlation was found between cytokeratin synthesis and hepatocyte growth. Most of the cytoskeleton proteins could be phosphorylated in intact cells and in DIM from cultured hepatocytes. However the degree of phosphorylation of these proteins was not related to their synthetic rate. The decreased phosphorylation level in cultured adult rat hepatocytes could be related to the rapid loss of specific functions.

[Prenatal diagnosis of abnormalities of the neuroectodermal tube. Limitations of the assay of amniotic alpha fetoprotein and acetylcholinesterase and value of the qualitative study of cholinesterases. Apropos of 6 cases of anencephaly]

Measurement of amniotic fluid alpha-foetoprotein and acetylcholinesterase for the detection of neural tube defects has been used in 285 normal or neural tube defects affected pregnancies: 18 false positive results (with non neural tube defects fetal malformations) have been reported. A qualitative polyacrylamide gel electrophoresis technique has been used to identify the acetylcholinesterase isoenzyme derived from foetal cerebrospinal fluid. Results illustrate the value of amniotic fluid acetylcholinesterase electrophoresis. Amniotic cholinesterase presence may serve as a valuable marker for the detection of neural tube defects.

[Changes in blood levels of haptoglobin and ceruloplasmin in vitamin A deficiency in Sprague-Dawley rats]

The aim of the present study was to find out whether the elevation of the serum ceruloplasmin level, previously described in vitamin-A-deficient rats, is a specific phenomenon. Quantitative variations of serum ceruloplasmin, albumin and haptoglobin (whose concentration increased during inflammation) were determined in normal and vitamin-A-deficient rats. Concentrations of ceruloplasmin, haptoglobin, and the value of the haptoglobin to albumin ratio are increased in the serum of vitamin-A-deficient rats compared to normal rats. The results suggested that the increased serum level of ceruloplasmin in vitamin-A-deficient rats was due to the presence of inflammation.