Objective. - Fructose consumption is increasing worldwide and is likely to play a role in metabolic disorders. Dietary fructose is often recommended for diabetic patients, as this form of carbohydrate leads to a lower postprandial rise in plasma glucose and insulin. However, fructose contributes to the generation of free radicals. The aim of this work was to investigate the acute effects of a fructose load in patients with type 2 diabetes mellitus (T2DM), compared with healthy controls, on several metabolic oxidative biomarkers, particularly plasma 15-F-2t isoprostanes (15-F-2t isoPs).Research design and methods. - Six T2DM patients and six healthy subjects were recruited. All patients underwent a single fructose tolerance test (75 a of anhydrous fructose). Plasma 15-F-2t isoPs concentrations, plasma total antioxidant capacity (TAS) and thiobarbituric acid reactive substances (TBARS) were measured at baseline, and at 60, 120, 180 and 240 min after fructose absorption.Results. - Baseline plasma 15-F-2t isoPs concentrations were significantly increased in T2DM patients compared with controls (310 +/- 47 versus 237 +/- 20 pg/mL, respectively; P < 0.01) and rose significantly (P < 0.01) to 414 +/- 45 pg/mL in diabetic patients. No change in TAS or TBARS was observed in either group.Conclusion. - Plasma 15-F-2t isoPs are increased during acute fructose loading in T2DM. Knowing the potentially deleterious effect of plasma 15-F-2t isoPs-in particular. vascular lesions-and in light of our results, it is necessary to reconsider fructose consumption in T2DM patients, as we can now show, for the first time, a possible association between acute fructose loading and deleterious effects in such patients. (C) 2008 Elsevier Masson SAS. All rights reserved.

La consommation de fructose augmente partout dans le monde et doit jouer un rôle dans les maladies métaboliques. Le fructose est souvent recommandé pour l'alimentation des patients diabétiques, car ce glucide produit une petite augmentation de la glycémie postprandiale et d'insuline. Le fructose contribue à la génération de radicaux libres. L'objectif de ce travail était d'explorer les effets d'une charge de fructose chez des sujets diabétiques de type 2 (DT2) par rapport aux contrôles sains sur plusieurs biomarqueurs du métabolisme oxydatif, en particulier les 15 F2t isoprostanes. Six DT2 patients et six sujets sains ont été recrutés. Les concentrations plasmatiques de 15-F2t isoprostane, la capacité totale antioxydant du sérum (TAS), et les TBARS ont été mesurés à l'inclusion et à 60, 120, 180 et 240 min après l'absorption de fructose. La taux basal de 15-F2t isoprostane était nettement augmenté chez les patients diabétiques par rapport aux sujets témoins (310 ± 47 contre 237 ± 20 pg/ml, p < 0,01) et a augmenté de façon significative (p < 0,01) à 414 ± 45 Pg/ml chez les patients diabétiques. Aucun changement pour les autres paramètres du stress oxydant n'ont été observés dans les deux groupes. Les concentrations de Plasma 15-F2t isoprostanes augmentent pendant une charge aiguë de fructose chez des patients diabétiques. Connaissant les effets potentiellement délétères des isoprostanes, en particulier sur le système vasculaire, nous devons reconsidérer la consommation de fructose dans le diabète de type 2.

This study aims to investigate the association between ADD tendency, with or without hyperactivity, and all types of unintentional injuries among adolescents. This study was a population-based health survey utilising a two-stage random cluster sampling design. The study was conducted among high school students in Nanning, the capital city of the Guangxi Province, China. Subjects were recruited from the total population of adolescents who attended high school years 1, 2, and 3 with ages ranging from 13 to 17 years. Information on ADD was collected by trained health professional via personal interviews. Other information, including unintentional injury was collected via a self-report health survey questionnaire. One thousand and twenty-nine (n = 1429) students were recruited with 115 (7.9%) identified as having a high ADD tendency, and 340 (22.6%) reported as having experienced an injury in the last 3 months. After adjusting for other potential confounding factors, results from the logistic regression analyses indicated that adolescents who scored high on the ADD tendency had an increased risk of injury by about 70% as compared to those who scored low (OR = 1.68, 95%CI = 1.18–2.40). ADD tendency has been identified as a potential risk factor of injury among adolescents. Screening for risk factors can be considered as a potential preventive strategy.

Glutamate is the most abundant excitatory neurotransmitter in the central nervous system, and is stored and released by both neurons and astrocytes. Despite the important role of glutamate as a neurotransmitter, elevated extracellular glutamate can result in excitotoxicity and apoptosis. Monosodium glutamate (MSG) is a naturally occurring sodium salt of glutamic acid that is used as a flavor enhancer in many processed foods. Previous studies have shown that MSG administration during the early postnatal period results in neurodegenerative changes in several forebrain regions, characterized by neuronal loss and neuroendocrine abnormalities. Systemic delivery of MSG during the neonatal period and induction of glutamate neurotoxicity in the cochlea have both been shown to result in fewer neurons in the spiral ganglion. We hypothesized that an MSG-induced loss of neurons in the spiral ganglion would have a significant impact on the number of neurons in the cochlear nuclei and superior olivary complex (SOC). Indeed, we found that exposure to MSG from postnatal days 4 through 10 resulted in significantly fewer neurons in the cochlear nuclei and SOC and significant dysmorphology in surviving neurons. Moreover, we found that neonatal MSG exposure resulted in a significant decrease in the expression of both calretinin and calbindin. These results suggest that neonatal exposure to MSG interferes with early development of the auditory brainstem and impacts expression of calcium binding proteins, both of which may lead to diminished auditory function.

Does single embryo culture under atmospheric or reduced oxygen alter preimplantation metabolism and post-implantation development compared with culture in groups?Mouse embryos were cultured under 5% or 20% oxygen, individually or in groups of 10. Spent media were analysed after 48, 72 and 96 h of culture. Blastocysts were assessed by outgrowth assay or transferred to pseudo-pregnant recipients, and fetal and placental weight, length and morphology were assessed.Compared with group culture, individually cultured blastocysts had lower net consumption of glucose and aspartate and higher glutamate production. Atmospheric oxygen reduced uptake of glucose and aspartate and increased production of glutamate and ornithine compared with 5% oxygen. Combining 20% oxygen and single culture resulted in further metabolic changes: decreased leucine, methionine and threonine consumption. Under 5% oxygen, individual culture decreased placental labyrinth area but had no other effects on fetal and placental development or outgrowth size compared with group culture. Under 20% oxygen, however, individual culture reduced outgrowth size and fetal and placental weight compared with group-cultured embryos.Preimplantation metabolism of glucose and amino acids is altered by both oxygen and individual culture, and fetal weight is reduced by individual culture under atmospheric oxygen but not 5% oxygen. This study raises concerns regarding the increasing prevalence of single embryo culture in human IVF and adds to the existing evidence regarding the detrimental effects of atmospheric oxygen during embryo culture. Furthermore, these data demonstrate the cumulative nature of stress during embryo culture and highlight the importance of optimizing each element of the culture system.

This proceedings report presents the outcomes from an international Workshop designed to establish consensus on the professional status of the Clinical Embryologist, and then to work towards creating international standards that can be referenced by regulators and professional societies around the world. The participants represented a total of 20 countries (Australia, Austria, Belgium, Brazil, Canada, China, Croatia, Finland, France, Germany, Ireland, Italy, the Netherlands, Russia, South Africa, Spain, Sweden, Turkey, UK and USA) and 18 national and regional societies (as presented in the list of participants). This report includes general presentations about current practice, and factors for consideration in the development of a competency-based framework for certification of Clinical Embryologists.

This study aims to investigate the association between ADD tendency, with or without hyperactivity, and all types of unintentional injuries among adolescents. This study was a population-based health survey utilising a two-stage random cluster sampling design. The study was conducted among high school students in Nanning, the capital city of the Guangxi Province, China. Subjects were recruited from the total population of adolescents who attended high school years 1, 2, and 3 with ages ranging from 13 to 17 years. Information on ADD was collected by trained health professional via personal interviews. Other information, including unintentional injury was collected via a self-report health survey questionnaire. One thousand and twenty-nine (n = 1429) students were recruited with 115 (7.9%) identified as having a high ADD tendency, and 340 (22.6%) reported as having experienced an injury in the last 3 months. After adjusting for other potential confounding factors, results from the logistic regression analyses indicated that adolescents who scored high on the ADD tendency had an increased risk of injury by about 70% as compared to those who scored low (OR = 1.68, 95%CI = 1.18–2.40). ADD tendency has been identified as a potential risk factor of injury among adolescents. Screening for risk factors can be considered as a potential preventive strategy.

This study aims to investigate the association between ADD tendency, with or without hyperactivity, and all types of unintentional injuries among adolescents. This study was a population-based health survey utilising a two-stage random cluster sampling design. The study was conducted among high school students in Nanning, the capital city of the Guangxi Province, China. Subjects were recruited from the total population of adolescents who attended high school years 1, 2, and 3 with ages ranging from 13 to 17 years. Information on ADD was collected by trained health professional via personal interviews. Other information, including unintentional injury was collected via a self-report health survey questionnaire. One thousand and twenty-nine (n = 1429) students were recruited with 115 (7.9%) identified as having a high ADD tendency, and 340 (22.6%) reported as having experienced an injury in the last 3 months. After adjusting for other potential confounding factors, results from the logistic regression analyses indicated that adolescents who scored high on the ADD tendency had an increased risk of injury by about 70% as compared to those who scored low (OR = 1.68, 95%CI = 1.18–2.40). ADD tendency has been identified as a potential risk factor of injury among adolescents. Screening for risk factors can be considered as a potential preventive strategy.

Stress tolerance can be induced in embryos by oocyte exposure to hydrostatic pressure, osmotic agents, heat shock, or reactive oxygen species. This study assessed the effects of exposing bovine oocytes to a nitric oxide (NO) donor, sodium nitroprusside (SNP), on subsequent in vitro embryo production, embryo quality and the expression of genes involved in NO production (iNOS, eNOS, and nNOS), stress tolerance (HSP70 and HSP90), oxidative stress (HIF1A and PRDX5), and apoptosis (BCL2A1). In vitro mature oocytes were incubated with SNP (control, 10−6M, 10−5M, and 10−4M) for 1 hour before in vitro fertilization, and cultured until Day 7. Cleavage and blastocyst rates were recorded. Next, embryo quality (ratio of inner cell mass to total cell number) and relative gene expression of iNOS, eNOS, nNOS, HSP70, HSP90, HIF1A, PRDX5, and BCL2A1 were determined in expanded blastocysts. Cleavage rates were significantly lower for 10−4M SNP compared with the control and 10−5M SNP treatments (77 ± 7.1%, 82 ± 8.4%, and 84.9 ± 4.1%, respectively). Total blastocyst rates were lower in the 10−4M SNP group relative to the control group (26.2 ± 4.9% and 34.1 ± 7.8%, respectively). Embryo quality was similar among the groups. However, our relative gene expression analysis revealed the downregulation of endothelial oxide nitric synthase messenger RNA in expanded blastocysts in all the treatment groups compared with the control treatment. These results suggest that the short-term exposure of mature bovine oocytes to a NO donor does not induce their stress tolerance and has no beneficial effect on the in vitro embryo production of bovine embryos.

The successful cryopreservation of mammalian embryos is often attributed to the application of theoretical considerations and empirical observations derived from other cellular systems. Two factors were found to be important in the cryopreservation of embryos, namely, the presence of molar concentrations of a protective solute such as dimethylsulfoxide (Me2SO) or glycerol, and the appropriate control of the rates of cooling and warming (15, 44, 48). Cryoprotective solutes of low molecular weight are thought to prevent the potentially deleterious exposure of cells to elevated concentrations of electrolytes by their colligative action in reducing the quantity of ice formed at any subzero temperature (17, 33). Control of the cooling and warming conditions determines the ultimate fate of intracellular water during the cryopreservation process (24). If the rate of cooling is sufficiently low, cytoplasmic water will flow out of the cells and freeze extracellularly. However, if cooling is too rapid, the cytoplasm will not have sufficient time to dehydrate. As a result, the cytoplasm will supercool and eventually freeze. The formation of intracellular ice is thought to lead to injury (26). Some studies, however, suggest that under

Mouse embryos (8-cell) fully equilibrated in 1.5 M-glycerol were cooled slowly (0.5 degrees C/min) to temperatures between - 7.5 and - 80 degrees C before rapid cooling and storage in liquid nitrogen (-196 degrees C). Some embryos survived rapid warming (approximately 500 degrees C/min) irrespective of the temperature at which slow cooling was terminated. However, the highest levels of survival of rapidly warmed embryos were observed when slow cooling was terminated between -25 and -80 degrees C (74-86%). In contrast, high survival (75-86%) was obtained after slow warming (approximately 2 degrees C/min) only when slow cooling was continued to -55 degrees C or below before transfer into liquid N2. Injury to embryos cooled slowly to -30 degrees C and then rapidly to -196 degrees C occurred only when slow warming (approximately 2 degrees C/min) was continued to -60 degrees C or above. Parallel cryomicroscopical observations indicated that embryos became dehydrated during slow cooling to -30 degrees C and did not freeze intracellularly during subsequent rapid cooling (approximately 250 degrees C/min) to -150 degrees C. During slow warming (2 degrees C/min), however, intracellular ice appeared at a temperature between -70 and -65 degrees C and melted when warming was continued to -30 degrees C. Intracellular freezing was not observed during rapid warming (250 degrees C/min) or during slow warming when slow cooling had been continued to -65 degrees C. These results indicate that glycerol provides superior or equal protection when compared to dimethyl sulphoxide against the deleterious effects of freezing and thawing.

Methanol was examined as a cryoprotective additive that permits the direct transfer of frozen--thawed Day-4 mouse embryos to foster mothers without dilution of the cryoprotectant. Methanol permeated the embryos rapidly, was not toxic and exerted a cryoprotective action. The highest level of survival (50%) of embryos in vitro was observed after equilibration in Medium PB1 containing 3.0 M-methanol, slow cooling (0.5 degrees C/min) to a temperature between -30 and -40 degrees C, rapid cooling (800 degrees C/min) and storage in liquid nitrogen (-196 degrees C), rapid warming (800 degrees C/min), and rapid dilution. A high rate of development in vivo to late-stage fetuses (up to 81%) was observed when cryopreserved embryos were transferred to pseudopregnant recipients immediately after thawing.

The blastomeres of eight-cell cow embryos were separated by micromanipulation into four pairs, inserted in foreign zonae pellucidae, embedded in agar and cultured for approximately four days in ligated sheep oviducts. Of 44 "quarter" embryos (11 monozygotic groups) transferred to sheep, 91 per cent had continued to develop at a normal rate and 77 per cent had formed small blastocysts with a single inner cell mass. Twenty-six blastocysts freed from the agar were transferred to heifers, each heifer receiving two monozygotic embryos, one to the tip of each uterine horn. Nine recipients were diagnosed pregnant by rectal palpation on day 50, six carrying twins. Thus 15 of the embryos had continued to develop including two sets of monozygotic quadruplets and one set of monozygotic triplets. Eight fetuses developed to full term, one set of monozygotic triplets, two sets of monozygotic twins (one set born dead) and one single.

Embryo culture techniques were used to maintain the viability of swine embryos during shipment from the United States to England. Embryos recovered surgically from Chester White and Hampshire sows and gilts were shipped to England, then transferred to Large White gilts. Estrus was synchronized between donors and recipients by including allyl trenbolone in the daily feed for 18 and 17 consecutive days, respectively. Daily dose of allyl trenbolone was 15 mg for recipients and either 15 or 20 mg for donors. Donors were mated or artifically inseminated one to three times during estrus. During shipment, embryos were cultured in groups of six to ten in polystyrene tubes (12 × 75 mm) containing 2 ml of a modified Krebs-Ringer bicarbonate medium. The gas phase was 90% nitrogen, 5% oxygen, and 5% carbon dioxide. Culture temperature was maintained at 35 C with a temperature-controlled box, and shipment was by commerical airline. Embryos were inserted into recipient uteri 20.5 to 27 hr after recovery. In total, 227 eggs were transferred to 12 recipients, resulting in the birth of seven litters totaling 58 pigs.

Pronuclear development was used to measure the effects on ovine oocytes of altering follicular steroidogenesis during maturation in vitro. Follicular steroid secretion was altered using enzyme inhibitors and exogenous steroid supplementation. Abnormalities induced during maturation were measured 24 h after tranfer of oocytes to the oviducts of inseminated hosts. The presence throughout maturation of aminoglutethimide, an inhibitor of the conversion of cholesterol to pregnenolone, reduced steroid secretion to 7% of that in controls and decreased from 77% to 33% the number of normal oocytes. Abnormalities were substantially reduced by the addition of aminoglutethimide during the final 8 h of maturation only. The inhibition of 17 alpha-hydroxylase enzymes with SU10603 reduced oestrogen and testosterone secretion to about 10% of control levels but had no effect on progestin secretion. Only 13% of oocytes matured in the continual presence of SU10603 underwent normal fertilization. The number of oocytes undergoing normal fertilization was increased to about 50% by (i) delaying the addition of SU10603 until the last 8 h of the maturation period or (ii) adding exogenous steroids to follicles cultured with inhibitor from explantation. It is concluded that oocytes require a specific intra-follicular steroid environment for the completion of the full maturation process. Alterations to the steroid profile during maturation induce changes in the oocyte which are expressed as gross abnormalities at fertilization.