Safety of Oxygreen®, an ozone treatment on wheat grains. Part 2. Is there a substantial equivalence between Oxygreen-treated wheat grains and untreated wheat grains?

The Oxygreen process is a new process based on wheat grain treatment by ozone (produced in situ), in a closed sequential batch reactor. The Oxygreen process offers a close, homogeneous, and controlled contact between the gas and the grain. It is proposed for use for wheat grain decontamination (insects, fungi, bacteria, mycotoxins, pesticides). It takes place in classical milling diagram, and occurs after grain cleaning and before milling. The aim of the study reported here was to determine if Oxygreen treatment could induce in the grain the formation of processing-related compounds, and if these compounds are specific or could be recognized as classical modifications already used in the cereal industry (milling, baking). Studies were performed in order to evaluate any effect of Oxygreen treatment on vitamins, ferulic acid, phytates, proteins, carbohydrates, and lipids. It was concluded that there was no detectable substantial difference between ozone-treated grains and the untreated ones, although some quantitative differences can occur. The more detectable differences concern concentration of free sugars, and inhibition of some oxidative enzymes. These quantitative differences are very slight compared to the modifications that occur in dough, after addition of oxidative products directly in flour, or during kneading and dough fermentation.

Safety of Oxygreen®, an ozone treatment on wheat grains.Part 1. A four-week toxicity study in rats by dietary administration of treated wheat

The Oxygreen process is a new treatment approved by The French Food Safety Authority (AFSSA) as a processing aid for flour quality improvement, based on treatment by ozone, in a closed sequential batch reactor. This treatment takes place in the classical milling sequence, after the grain-cleaning step and before milling. The Oxygreen process could also be used for its properties in wheat grain decontamination (insects, fungi, bacteria, mycotoxins, storage insecticides residues). The aim of this study was to determine if Oxygreen treatment could induce in the grain the formation of processing-related substances, able to provoke adverse effects, after ingestion of the wheat and/or derived products, and to establish the safety of the Oxygreen process for animals and consumers. A four-week toxicity study, according to OECD guideline No. 407, was performed on Dark agouti rats fed exclusively with wheat grains, treated or untreated with Oxygreen. Clinical, haematological, blood biochemical, urinary and histopathological parameters were investigated during the study. The few modifications observed in animals given treated wheat were an increase of rectal temperature in females, a slight decrease of calcium concentration in males and slight decrease of certain blood cell number without clinical significances. This work shows that wheat treated by Oxygreen does not induce adverse effects in Dark agouti rats after oral administration. Therefore wheat and derived products from wheat, after Oxygreen treatment on grain, could be considered as safe for the consumer.

Effects of systemic lupus erythematosus on spatial cognition and cerebral regional metabolic reactivity in BxSB lupus-prone mice

Brain-reactive auto-antibodies appear as key elements in the progressive CNS disturbances associated with systemic lupus erythematosus. The BxSB lupus prone mice are a model of this pathology, in which a gene located on the Y chromosome provokes a sex specific morbidity in males. This study was aimed to establish and characterize the relationships between behavioral disorders, neurological deficiencies and the aged-related immunological perturbations in this murine model. For this purpose, spatial and motor abilities were evaluated in male and female mice at six and 26 weeks of age. The results showed that the older males were greatly altered in their spatial abilities while the young ones and the females, whatever their age, were not. None of the animals had motor skill and motor learning disabilities. These spatial alterations were associated with modifications of basal neuronal activity measured by the cytochrome oxidase histochemical method in several areas directly or indirectly involved in spatial behavior, such as the hippocampus, the amygdala, the parietal and perirhinal cortex. Immunological study allowed us to correlate the behavioral abnormalities to the appearance of antibodies reactivities against cellular and nuclear components.

Mice with the deleted neurofilament of low molecular weight (Nefl) gene: 2. Effects on motor functions and spatial orientation

Mice with a null mutation of the Nefl gene were compared with normal controls in tests of motor activity, equilibrium, and spatial orientation. Despite a normal capacity to ambulate, NFL -/- mice had fewer rears in an open field, crossed fewer segments on stationary beams, and fell more frequently when suspended on a horizontal bar. In addition, the distance swum before reaching the escape platform was greater in NFL -/- mice than in controls during acquisition of place learning in the Morris water maze at the start of training. The motor impairments were linearly correlated with increased cytochrome oxidase activity seen in cerebellum and brainstem. These results indicate that, as early as 6 months, depletion of the NFL protein is sufficient to cause mild sensorimotor dysfunctions and spatial deficits, but without overt signs of paresis.

Mice with the deleted neurofilament of low-molecular-weight (Nefl) gene: 1. Effects on regional brain metabolism

Neuronal intermediate filaments consist of the NFL subunit linked with NFM and NFH, and their alterations have been proposed as a pathogenesic cause in motor neuron diseases. Depletion of the Nefl gene in mice mimicks the reduced NFL mRNA levels seen in amyotrophic lateral sclerosis and causes perikaryal accumulation of neurofilament proteins and axonal hypotrophy in motoneurons. NFL -/- mice were evaluated for regional brain metabolism by means of quantitative histochemical estimation of cytochrome oxidase (COx) activity. The NFL null mice displayed enzymatic activity alterations in numerous hindbrain regions, mainly the cerebellum, connected regions of the brainstem (red nucleus, vestibular nuclei, and reticular formation), and cranial nerve nuclei. All of the affected regions presented elevated COx activity, except for the Purkinje cells of the cerebellum and the magnocellular red nucleus, where enzymatic activity was lower. NFL-disrupted mice displayed functional alterations in brainstem sensorimotor regions affected in amyotrophic lateral sclerosis.

Efficient and sensitive detection of residues of nine coccidiostats in egg and muscle by liquid chromatography–electrospray tandem mass spectrometry

We present a method based on electrospray liquid chromatography tandem mass spectrometry (LC-MS/MS) for determining in muscle and eggs the following nine coccidiostats: halofuginone, diclazuril, dinitrocarbanilide (the main metabolite of nicarbazin), robenidine, monensin, lasalocid, narasin, salinomycin, and maduramicin. Dinitrocarbanilide-d8, nigericin, and diclazuril-bis were used as internal standards. The method uses extraction in acetonitrile followed by a clean-up on an SiOH solid-phase extraction column. High-performance liquid chromatography (HPLC) separation was performed on a Purospher C(18) column (125 mm x 3 mm i.d.) protected by a guard column, the mobile phase being a water-acetonitrile gradient (each gradient component containing 0.1% formic acid) at a flow rate of 1 ml min(-1). For unequivocal identification of each analyte, two ions were detected and chosen for multiple reaction monitoring (MRM). Validation was carried out on spiked muscle and egg samples. The method described meets all the criteria of Decision 2002/657/EC and is easy to use in routine analysis. Validation results are presented with the measured CCalpha and CCbeta values. This whole method allows extraction and analysis of up to 24 samples per day.

Human chorionic gonadotropin and growth factors at the embryonic-endometrial interface control leukemia inhibitory factor (LIF) and interleukin 6 (IL-6) secretion by human endometrial epithelium

BACKGROUND

The elucidation of the molecular mechanisms by which the embryo contributes to its implantation is an area of extensive research. The main objective of this study was to investigate the pattern of leukemia inhibitory factor (LIF) and interleukin-6 (IL-6) secretion by human endometrial epithelium, and their regulation by human chorionic gonadotropin (hCG) and other growth factors present at the embryonic-endometrial interface.

METHODS

Endometrial epithelial cells (EEC) were isolated from biopsies collected at both proliferative and secretory phases of fertile women.

RESULTS

HCG (1-50 IU/ml) increased LIF secretion by EEC cultures derived from follicular phase (up to 285+/-75%) or from secretory phase (up to 212+/-16%). In contrast, hCG reduced IL-6 secretion by EEC in both phases. The hCG/LH receptor gene was transcribed by EEC as evidenced by RT-PCR. Insulin-like growth factors 1 and 2 increased LIF secretion by EEC. Transforming growth factor beta1 stimulated LIF and reduced IL-6 secretion.

CONCLUSIONS

Through hCG, the blastocyst may be involved in the control of its implantation (via an increase of proimplantatory LIF) and tolerance (via an inhibition of proinflammatory IL-6). Other growth factors present at the embryonic-endometrial interface are also involved in the control of LIF and IL-6 endometrial secretion.

Electrochemical impedance spectroscopy and electron spin resonance characterization of the conductive state of parasexiphenylene electrochemically intercalated with sodium

The electrochemical intercalation of sodium ions into parasexiphenylene (PSP) was studied by electron spin resonance (ESR) and electrochemical impedance spectroscopy (EIS). These complementary techniques give informations about the conduction state of the host material as a function of the doping rate both in the intercalation and deintercalation processes. These data were compared to the previous works concerning the intercalation of alkaline ions into polyparaphenylene (PPP).

Semiconducting surface reconstructions of p-type Si(100) substrates at 5 K

We report scanning tunneling microscopy (STM) studies of the technologically important Si(100) surface that reveal at 5 K the coexistence of stable surface domains consisting of the p(2 x 1) reconstruction along with the c(4 x 2) and p(2 x 2) reconstructions. Using highly resolved tunneling spectroscopic measurements and tight binding calculations, we prove that the p(2 x 1) reconstruction is asymmetric and determine the mechanism that enables the contrast variation observed in the formation of the bias-dependent STM images for this reconstruction.

Non-esterified fatty acids are deleterious for human pancreatic islet function at physiological glucose concentration

AIMS/HYPOTHESIS

Whether excess glucose (glucotoxicity) and excess non-esterified fatty acids (lipotoxicity) act synergistically or separately to alter beta-cell function on Type 2 diabetes remains controversial. We examined the influence of non-esterified fatty acids, with or without concomitant increased glucose concentrations, on human islet function and on the expression of genes involved in lipid metabolism.

METHODS

Human islets isolated from non-diabetic and non-obese donors were cultured with 5.5, 16 or 30 mmol/l glucose, and when appropriate with 1 or 2 mmol/l non-esterified fatty acids. After 48 h, glucose-stimulated insulin secretion, insulin content, triglyceride content and expression of different genes were evaluated.

RESULTS

Non-esterified fatty acids decreased glucose-stimulated insulin secretion, insulin content and increased triglyceride content of human isolated islets, independently from the deleterious effect of glucose. Increased glucose concentrations also decreased glucose-stimulated insulin secretion and insulin content, but had no influence on triglyceride content. Glucose-stimulated insulin secretion of islets appeared to be significantly correlated with their triglyceride content. Glucose and non-esterified fatty acids modified the gene expression of carnitine palmitoyltransferase-I, acetyl-CoA carboxylase, acyl-CoA oxidase and uncoupling protein 2.

CONCLUSION/INTERPRETATION

In our model of isolated human islets, increased glucose and non-esterified fatty acids separately reproduced the two major beta-cell alterations observed in vivo, i.e. loss of glucose-stimulated insulin secretion and reduction in islet insulin content. Our results also suggest that this deleterious effect was, at least in part, mediated by modifications in lipid metabolism gene expression.

Anticorps anti-ovaires et fécondation in vitro : cause ou conséquence ?

OBJECTIVES

To assess anti-ovarian antibodies (AOA) in serum samples at various times of in vitro fertilization (IVF) attempts to determine whether ovarian stimulation could result in the production of such autoantibodies in women.

PATIENTS AND METHODS

Prospective study on 134 patients and 138 IVF cycles using a classical long protocol. For each attempt, four serum samples were obtained, respectively, at the onset of downrelation (S1), end of downregulation (S13), after 7 days of follicular stimulation (S21) and the day of follicular puncture (SP). Five hundred and fifty two samples were tested with an enzyme-linked immunosorbent assay for three isotypes (IgG, IgA, IgM) of AOA.

RESULTS

In the whole group, mean concentrations of AOA for each isotype were compared group by group: S1-S13, S1-S21, S1-SP, S13-S21, S13-SP, S21-SP. Not any significant difference was observed whatever the isotype considered.

DISCUSSION AND CONCLUSION

This study shows the absence of influence of endogenous or exogenous ovarian stimulation by gonadotropins on anti-ovarian autoimmunity.

Evidence of a limited contribution of feto-maternal interactions to trophoblast differentiation along the invasive pathway

Trophoblast differentiation is a key event in human placental development. During extravillous trophoblast (EVT) differentiation, stem cells from the anchoring villi detach from their basement membrane and proliferate to form aggregates called trophoblast cell columns (TCCs). They subsequently invade the decidua and differentiate into interstitial and endovascular trophoblasts. The influence of the decidua on EVT differentiation is controversial. We therefore compared the pattern of trophoblast differentiation marker expression in viable intrauterine and tubal pregnancies, as decidual cell markers (prolactin [PRL] and insulin-like growth factor binding Protein-1 [IGFBP1]) were only expressed in endometrial implantation sites. Extravillous trophoblast differentiation in anchoring villi from uterine and ectopic pregnancies exhibited a comparable phenotypical switch: alpha6 integrin subunit, E-cadherin, EGF receptor, Ki 67 and connexin 40 were localized in the proximal part of the TCC, while alpha5beta1 and alpha1 integrins, c-erb B2, hPL and HLA-G were expressed by invasive cytotrophoblasts. The cyclin-dependent kinase inhibitors p16 and p57 were mainly detected in invasive cytotrophoblasts some distance from the columns. However, the TCC was markedly longer in tubal pregnancy than in intrauterine pregnancy. These findings suggest that the decidua is not necessary to trigger EVT invasion, but that it is likely to limit the extent of the TCC and to accelerate the onset of EVT migration.

Twin pregnancy obtained with frozen-thawed embryos after in vitro maturation in a patient with polycystic ovarian syndrome

PURPOSE

A twin pregnancy was obtained in a patient with polycystic ovary syndrome after the transfer of three in vitro maturation-derived day 3 embryos that has been frozen and thawed.

METHODS

The patient had received mild hMG stimulation followed by hCG injection. After culture for 24-48 h, mature oocytes were fertilized by ICSI. Embryos were cultured until day 3; supernumerary embryos were cryopreserved using a slow protocol.

RESULTS

Among 15 nonatretic oocytes, 9 matured, 8 were fertilized. Four embryos were transferred but they did not implant. The subsequent transfer of three frozen-thawed embryos resulted in the delivery of two healthy girls.

CONCLUSIONS

These results indicate that a pregnancy could be obtained with in vitro maturation-derived day-3 frozen-thawed embryos.

Raman spectroelectrochemical study of sodium intercalation into poly(p-phenylene)

The structural defects formed along the polymer chain during the electrochemical intercalation of sodium into polyparaphenylene (PPP) were investigated by in situ FT Raman measurements with an excitation wavelength of 1064 nm. Our Raman data are compared with those obtained for PPP and its oligomers intercalated with Na(+) ions by chemical ways. The coexistence of polarons and bipolarons is observed in the early stages of the intercalation process. When the doping level increases polarons are transformed to bipolarons, then in the highly intercalated sample (corresponding to a composition close to Na(0.5)(C(6)H(4))), bipolarons are the main structural defects. This evolution, which is reversible, is in accordance with the electron spin resonance (ESR) data of PPP intercalated with sodium ions in the same experimental conditions.

On-line measurement of texture, thickness and plastic strain ratio using laser-ultrasound resonance spectroscopy

Laser-ultrasound resonance spectroscopy, a non-contact ultrasonic technique, was used to determine reliably and rapidly the crystallographic texture, the average plastic strain ratio, and the thickness of sheet metal on the production line. As with laser-ultrasonics, a short laser pulse is used to generate a wide-band pulse of ultrasound and a laser interferometer is used for its detection. In this paper, a large number of echoes are collected and analyzed together using Fourier techniques to measure the natural resonance frequencies in the thickness of the sheet. One longitudinal and two shear resonance frequencies were measured together with their harmonics. From these frequencies, two crystallographic orientation distribution coefficients, W(400) and W(420), are obtained, as well as a highly accurate measurement of the sheet thickness that is corrected for changes in ultrasonic velocity caused by texture variations. Using these coefficients, the average and in-plane twofold and fourfold variations of the plastic strain ratio, respectively r delta(2)r, and delta(4)r, can be evaluated. These parameters are indications of the formability of metals sheets, which is of industrial interest. Measurements on 1 mm thick, low carbon steel sheets have shown the following measurement accuracies: r to within +/-0.08, delta(2)r, and delta(4)r to within +/-0.1, and thickness to better than +/-1 microm. On-line tests at LTV Steel Company showed that the sensitivity of the apparatus is sufficient to detect systematic variations in texture along the length of similar production coils and that the on-line repeatability for r was of order +/-0.02.

[Thiazolidinediones in type 2 diabetes. Role of peroxisome proliferator-activated receptor gamma (PPARgamma)]

Thiazolidinediones (TZDs) form a new class of oral antidiabetic agents. They improve insulin sensitivity and reduce glycemia, lipidemia and insulinemia in patients with type 2 diabetes. Their mechanism is original, since they activate the nuclear receptor Peroxisome Proliferator-Activated Receptor gamma (PPARgamma), altering the expression of genes involved in glucose and lipid homeostasis. Stimulating PPARgamma improves insulin sensitivity via several mechanisms: 1) it raises the expression of GLUT4 glucose transporter; 2) it regulates release of adipocyte-derived signaling factors that affect insulin sensitivity in muscle, and 3) it contributes to a turn-over in adipose tissue, inducing the production of smaller, more insulin sensitive adipocytes. TZDs also affect free fatty acids (FFA) lipotoxicity on islets, improving pancreatic B-cell function. In addition, triglycerides and FFA levels are lowered by TZDs. Two TZDs, rosiglitazone and pioglitazone, have recently obtained the European commercial licence, but their use is restricted to the association with metformin or sulfonylureas. At the moment, they are indicated in type 2 diabetes but could be of interest in a broader array of diseases related to insulin resistance. As for side effects, rosiglitazone and pioglitazone may cause increased plasma volume, edema and dose-related weight gain. TZDs offer an attractive option in the treatment of type 2 diabetes, though it may be too soon to determine if they prevent vascular complications, as do other oral antidiabetic agents. An important issue for the future will be to assess the influence of weight gain in the long time.

NFH-LacZ transgenic mice: regional brain activity of cytochrome oxidase

Expression of the NFH-LacZ fusion protein in transgenic mice causes an early accumulation of neurofilament proteins in the cell bodies of neurons, as well as a reduction of motor neuron axonal caliber and Purkinje cell number in the cerebellum. Young (3 month old) and older (12-20 months) NFH-LacZ transgenic mice were compared to normal controls for regional brain metabolism, as assessed by cytochrome oxidase (CO) activity. Irrespective of age, CO activity was reduced in three cerebellar-related regions of NFH-LacZ transgenic mice: (1) the lateral reticular nucleus, (2) the parvicellular red nucleus, and (3) the superior colliculus, possibly as a secondary consequence of cerebellar Purkinje cell histopathology. Aged NFH-LacZ mice had lower CO activity relative to either age-matched controls or young transgenic mice in the following regions: the motor nucleus of the vagus nerve, the trapezoid nucleus, the subiculum, the motor cortex, the superior olive, and the lateral dorsal thalamus. These results indicate regional and age-selective deficits of brain metabolism in a transgenic model with neurofilament maldistribution.