Implication of non-coding PAX6 mutations in aniridia

There is an increasing implication of non-coding regions in pathological processes of genetic origin. This is partly due to the emergence of sophisticated techniques that have transformed research into gene expression by allowing a more global understanding of the genome, both at the genomic, epigenomic and chromatin levels. Here, we implemented the analysis of PAX6, whose coding loss-of-function variants are mainly implied in aniridia, by studying its non-coding regions (untranslated regions, introns and cis-regulatory sequences). In particular, we have taken advantage of the development of high-throughput approaches to screen the upstream and downstream regulatory regions of PAX6 in 47 aniridia patients without identified mutation in the coding sequence. This was made possible through the use of custom targeted resequencing and/or CGH array to analyze the entire PAX6 locus on 11p13. We found candidate variants in 30 of the 47 patients. 9/30 correspond to the well-known described 3' deletions encompassing SIMO and other enhancer elements. In addition, we identified numerous different variants in various non-coding regions, in particular untranslated regions. Among these latter, most of them demonstrated an in vitro functional effect using a minigene strategy, and 12/21 are thus considered as causative mutations or very likely to explain the phenotypes. This new analysis strategy brings molecular diagnosis to more than 90% of our aniridia patients. This study revealed an outstanding mutation pattern in non-coding PAX6 regions confirming that PAX6 remains the major gene for aniridia.

Evaluation of the use of esterified fatty acid oils enriched in medium-chain fatty acids in weight loss diets for dogs

Esterified fatty acid oils (EAOs) are obtained from esterification of vegetable acid oils with glycerol. These fat sources have the same fatty acid (FA) composition as their respective native oils but new chemical properties. Several studies have confirmed the potential of medium-chain fatty acids (MCFA) to reduce fat mass (FM) in humans and rodents. This study investigates the use of EAOs with different MCFA proportions on food preferences, digestibility and weight loss management in dogs. A basal diet was supplemented with 8% of three different fat sources: C0: soya bean-canola EAO, C20: soya bean-canola (80%) coconut (20%) EAO and C40: soya bean-canola (60%) coconut (40%) EAO. Food preference of these EAOs was tested using a two-pan preference test. Dogs presented a higher daily food intake of C20 and C40 compared to C0 (C20: 155 ± 18.6 g vs. C0: 17 ± 7.0 g, p < 0.001; C40: 117 ± 13.9 g vs. C0: 28 ± 10.5 g, p < 0.05 respectively). Also, the digestibility of the three experimental diets was tested. C20 and C40 showed higher ether extract, total FA and saturated FA digestibilities (p < 0.05) than C0 diet. Lastly, the three diets were investigated in a 14-week weight loss study, following 16 weeks of ad libitum feeding to induce overweight condition. Body weight (BW) reduction was lower (C0: 20.1 ± 2.32%, C20: 14.6 ± 1.43% and C40: 15.7 ± 1.23%, p < 0.05) and FM was higher (FM, 18.7 ± 3.42%, 27.9 ± 3.90% and 28.2 ± 2.88% for C0, C20 and C40, respectively, p < 0.05) for diets C20 and C40 than for C0. Feeding diets with MCFA at these inclusion levels to experimentally overweight dogs during 14 weeks do not result in faster weight loss compared to unsaturated long-chain FA.

Comparison of postprandial lipaemia between native and palm random esterified acid oils in two different monogastric species (dogs and broiler chickens)

It has been reported that applying a chemical reesterification process to a native fat results in a new fat source with different physicochemical properties due to their different fatty acid (FA) positional distribution within the glycerol moiety and their different proportions of mono (MAG)-, di (DAG)- and triacylglycerides (TAG). Thus, this reesterification could affect fat digestion, absorption and metabolism; and this effect could vary among species given their differences in fat metabolism. The aim of this study was to compare the effect of feeding two different random esterified acid oils (REAO), presenting different MAG, DAG and TAG proportions, with their corresponding native oil on postprandial lipaemia in broiler chickens and dogs. For this purpose, 18 dogs and 54 broiler chickens were fed a basal diet supplemented with palm native oil, palm REAO low MAG or palm REAO high MAG. The inclusion level of the oils was 10% of the diet in dogs and 6% in broiler chickens. Serum postprandial TAG concentration (mg/dl) after feeding a single meal was measured at different time points during 12 h in dogs and 3 h in chickens. Although fasting serum TAG concentration values were similar for both species (47 ± 2.4 mg/dl for dogs and 44 ± 3.0 mg/dl for broilers; p = 0.522), postprandial TAG concentrations tended to be higher in broilers than in dogs (p = 0.058). Treatment had no effect on TAG concentration at any time point in any species (p = 0.768 for dogs, p = 0.947 for broilers). However, the postprandial TAG curves were very different between species; in broiler chickens, TAG concentration returned to the fasting values 3 h after feeding while in dogs, the TAG concentration still had not returned to basal levels 12 h after feeding.

Effects of 7-weeks competitive training period on physiological and mental condition of top level judoists

AIM

We examined hormonal and haematological parameters and the profile of mood states (POMS) in top level judoists undertaking a 7-week competitive training period in a real contest.

METHODS

Participants were 10 top level judoists belonging to the Spanish National Team. Training load was calculated by multiplying the training session intensity by the duration of the training session. The judoists competed in two official events on weeks 3 and 6 of the study.

RESULTS

Urinary catecholamines increased at the end of the competitive period. Serum cortisol increased during the weeks in which judoists competed, confirming the existence of and anticipatory cortisol response to exercise; although we failed to find serum testosterone increases. Because of leukocyte values did not change, except monocytes, we speculate that the intensity of training was not sufficiently high to evoke injury to muscle tissue. Anger, tension, and fatigue increased according with training load, suggesting that the training exercise led participants into a negative psychological state.

CONCLUSION

Findings indicate that during competitive periods, judoists suffer hormonal and mood changes according to training load and competitive events. Results support the usefulness of monitoring biological and psychological markers during season in order to adjust training loads and periods of recovery.

High levels of dietary unsaturated fat decrease alpha-tocopherol content of whole body, liver, and plasma of chickens without variations in intestinal apparent absorption

An experiment was designed to assess the effect of dietary unsaturated fat inclusion level on alpha-tocopherol apparent absorption and deposition in broiler chickens at 2 ages (20 and 39 d). The dietary fat was a mixture of linseed and fish oil, rich in polyunsaturated fatty acids (PUFA). The experimental treatments were the result of 4 levels of supplementation with alpha-tocopheryl acetate (0, 100, 200, and 400 mg/kg; E0, E100, E200, and E400 treatments, respectively) and 4 dietary oil inclusion levels (2, 4, 6, and 8%; O2, O4, O6, and O8 treatments respectively). Almond husk was used as an energy dilutor in the high-fat diets. Apparent absorption of total fatty acids was high in all treatments averaging 88% and was higher with high fat dietary inclusion level. alpha-Tocopheryl acetate hydrolysis and apparent absorption of alpha-tocopherol were similar in both ages and were not affected by fat inclusion level, except for a reduction of the absorption in the low-fat diet (O2) in the E100 treatment at 20 d of age. Despite this lack of differences in hydrolysis and absorption, higher-fat PUFA diets induced lower concentrations of free alpha-tocopherol in the excreta, at high alpha-tocopherol doses, suggesting an increase in the destruction of alpha-tocopherol by lipid oxidation in the gastrointestinal tract. Similarly, total and hepatic alpha-tocopherol deposition was lower in the birds fed high-PUFA diets in the E200- and E400-supplemented birds, possibly due to a destruction of vitamin E when protecting these PUFA from lipid peroxidation. alpha-Tocopherol concentration in liver and, to a lesser extent, in plasma was a useful indicator of the degree of response of this vitamin to different factors that can affect its bioavailability; however, in the present experiment, CV were too high to use liver and plasma concentrations as estimators of total body vitamin E.

Endorphin responses to stress induced by competitive swimming event

AIM

The aim of the present study was to investigate the changes in endorphins (END) induced by swimming competitive practice.

METHODS

Twenty-three males, (13 trained swimmers [experimental group] and 10 sedentary and healthy students [age-matched comparison group]) took part in this investigation. The swimmers were assessed at 3 points: basal conditions, pre- and postswimming competition (100 m freestyle), whereas subjects from the control group only undertook the basal trial. The variables analysed were anxiety level, plasma END and lactate concentrations.

RESULTS

No statistical differences were observed in END basal levels between groups. An evident END response to precompetition psychological stress was observed in the experimental group, since the plasma END concentration rose from 36.3+/-2.9 pg/mL (basal conditions) to 51.8+/-3.2 pg/mL (P=0.05). The END response to the competitive effort produced a remarkable increase in its plasma concentration (128.6+/-18.1 pg/mL), showed statistical differences from precompetition (P=or<0.01) and from basal conditions (P=or<0.001). A significant rise in plasma lactate levels just at the end of the effort was found, although it did not correlate with END levels in the same situation.

CONCLUSION

Swimming competition (short-term maximal type of effort) induces a psychological and physiological stress, which stimulates the secretion of END. END are secreted to counter the negative effects of competitive stress, although more research is needed to accurate the relationship between END and anxiety levels during exercise.

Effects of dietary concentration and degree of polyunsaturation of dietary fat on endogenous synthesis and deposition of fatty acids in chickens

Two experiments were performed to assess the effect of different amounts of dietary polyunsaturated fatty acids (PUFA) on fatty acid composition of chickens. The contribution of de novo fatty acid synthesis to fatty acid profile was also estimated. In trial 1, different fat sources were blended in different ratios allowing a gradient of dietary PUFA (from 15 to 61 g/kg), keeping added fat constant (9%). In trial 2, PUFA-rich oil was added at increasing inclusion rates (2, 4, 6 and 8%), achieving a dietary PUFA content ranging between 27 and 59 g/kg. Increasing dietary PUFA inclusion resulted in an increase in PUFA deposition, with higher efficiency when dietary fat also provided saturated (SFA) and monounsaturated (MUFA) fatty acids (trial 1). Increasing dietary PUFA in both trials resulted in a decrease in SFA and MUFA concentration in the whole body. The estimated deposition of fatty acids from de novo synthesis was reduced when dietary fat content increased from 0 to 10%, varying between 35.34 and 17.66% for SFA and between 52.70 and 7.01% for MUFA in the whole body. The greater variation range for the MUFA supports the existence of a mechanism maintaining the SFA: (MUFA + PUFA) ratio within a specific range in biological membranes.

Influence of the dietary polyunsaturation level on chicken meat quality: lipid oxidation

The present study was carried out to evaluate the influence of increasing amounts of dietary polyunsaturated fatty acids (PUFA) and alpha-tocopheryl acetate (alpha-TA) supplementation on lipid oxidation of raw and cooked thigh meat stored under refrigeration. One hundred ninety-two female, 1-d-old, broiler chickens were randomly distributed into 16 experimental treatments resuIting from the combination of 4 levels of dietary PUFA (15, 34, 45, and 61 g/kg) and 4 levels of supplementation with alpha-TA (0, 100, 200, and 400 mg/kg). Thiobarbituric acid reactive substance (TBARS) values in cooked meat and cooked refrigerated meat were 12- and 24-fold higher, respectively, than in raw meat. Dietary polyunsaturation and alpha-TA supplementation affected lipid oxidation more markedly in cooked meat and cooked refrigerated meat than in raw meat and raw refrigerated meat. Lipid oxidation in cooked meat showed a significant linear increase as the concentration of PUFA in raw meat increased. The oxidative stability of meat was not affected by an increase in the dietary alpha-TA level from 200 to 400 mg/kg. Nonlinear relationship between TBARS values in cooked meat and alpha-tocopherol content of raw meat showed saturation in the antioxidant effect of alpha-Toc. The equation y = x (11.88 + 63.38e(-0.007z) was calculated to predict the minimum inclusion of alpha-tocopherol to diets (z) of chickens with certain dietary PUFA content (x) to assure a certain TBARS value (y).

Fatty Acid Content in Chicken Thigh and Breast as Affected by Dietary Polyunsaturation Level

One hundred ninety-two female broiler chickens were randomly distributed into 16 experimental treatments as a result of the combination of 4 levels of dietary polyunsaturated fatty acids (PUFA) (15, 34, 45, and 61 g/kg) and 4 levels of supplementation with alphatocopheryl acetate (alpha-TA) (0, 100, 200, and 400 mg/kg), to determine the modification of the amount and type of fatty acids (FA) deposited in raw and cooked chicken tissues. At 44 d, quantified FA of thighs and breasts were not affected by dietary supplementation with alpha-TA. Total FA content of breast was less than 15% of the total FA content of thigh. However, increasing the PUFA content of the diet by 46 g, from 15 to 61 g/kg, decreased total FA of thigh 17%, but did not affect FA content in breast meat. Monounsaturated fatty acid (MUFA) and saturated fatty acid (SFA) content of thigh (y) decreased linearly as the inclusion of dietary PUFA (x) increased (MUFA: y = 89.34 - 0.92x, R2 = 0.70; SFA: y = 53.81 - 0.43x, R2 = 0.57), whereas the relationship between PUFA content of feed (x) and thighs (y) was exponential (y = 92.03 92.03e(-00155x), R2 = 0.75). A similar response was observed in breast, with less variation and more incorporation of PUFA than thigh. Cooking of thigh meat led to a reduction in total FA content that affected SFA, MUFA, and PUFA in a similar proportion.

Relationship between dietary unsaturation and vitamin E in poultry

Vitamin E requirements are linked to dietary polyunsaturated fatty acids (PUFA) content as a result of the protective effect of vitamin E from lipid peroxidation. On the other hand, it has been suggested that dietary PUFA interfere with vitamin E absorption. A 4 x 4 factorial study was planned to assess the effect of dietary vitamin E inclusion level (0, 100, 200 and 400 mg/kg) and degree of unsaturation (15, 34, 45 and 61 g PUFA/kg) on vitamin E apparent absorption and tissue deposition in poultry. A total of 192 female broiler chickens were used. A digestibility balance was carried out between 19 and 23 days of age to calculate apparent absorption of fat and vitamin E. The livers of 96 animals were obtained at 44 days of age for vitamin E determination. Increasing dietary levels of vitamin E reduced its apparent absorption. The more saturated diet reduced fat and vitamin E apparent absorption while PUFA levels from 34 to 61 g/kg did not modify this parameter but reduced the hepatic vitamin E concentration, suggesting a greater systemic use of this vitamin. These results suggest that PUFA do not limit vitamin E absorption, although they may increase its degradation in the gastrointestinal tract.

Fibrinogen and fibrinolysis in blood and in the arterial wall: its role in advanced atherosclerotic disease

High plasma fibrinogen appears to be an important risk factor for the development of atherosclerosis. The aim of our study was to measure fibrinogen and fibrin degradation products (D-dimer), interleukin-6 tissue plasminogen activator, plasminogen activator inhibitor-1 and urokinase-type plasminogen activator in the plasma and arterial walls of 45 patients who had arterial surgery between April 1993 and November 1995. The arterial specimens were also examined by immunohistochemists for these same factors. The serum fibrinogen and fibrin degradation products were high in all patients, and fibrinolysis was depressed. Few leukocytes were seen in the arterial walls, which had poor fibrinolytic activity. Plasminogen-activator inhibitor activity in the wall was also reduced in the affected arterial walls. The abdominal aorta appeared to have the highest levels of fibrinogen and this may be related to its ability to form aneurysms. Fibrinogen may play an important role in the progression of atherosclerotic disease.

Influence of surfactants on oral bioavailability of albendazole based on the formation of the sulphoxide metabolites in rats

The influence of two surfactants, sodium taurocholate (STC) and polysorbate 80 (P80), on the bioavailability of albendazole (ABZ), orally administered to rats, has been studied. To assess the effect of the surfactants, they were administered at critical micellar and supramicellar concentrations, 5 and 10 mM for STC and 0.0022 and 0.22% for P80, along with a subclinical dose of 5 mg kg-1 of ABZ. Doses of 5 and 10.6 mg kg-1 ABZ were also administered as controls. The results show an increase in the sulphoxide AUC values: 55% in the STC 5 mM and 88% in the STC 10 mM and P80 0.0022% treatments when compared to the control ABZ 5 mg kg-1 dose. MRT values also show longer-lasting plasma albendazole sulphoxide concentration following these three treatments, particularly for the P80 0.0022% treatment. While there was no change in the apparent rate of formation of ABZSO, the amount of ABZSO formed was increased significantly by the addition of surfactants (STC 10 mM and P80 0.0022%).

Plasma concentrations of beta-endorphin and adrenocorticotropic hormone in women with and without childbirth preparation

We studied plasma concentrations of beta-endorphin (beta-EP) and adrenocorticotropic hormone (ACTH) during dilation, expulsion and immediate puerperium in 47 primiparous women with an uneventful pregnancy and spontaneous vaginal delivery. Twenty-five women had received childbirth preparation with the Lamaze method, and 22 had received no preparation. Mean concentrations of beta-EP from the beginning of labor until puerperium were higher in women who had received preparation, but there was no significant difference between the two groups. When behavior during labor was evaluated regardless of which group the patient was assigned to, women whose behavior was unsatisfactory has significantly higher concentrations of ACTH at all times during childbirth. We discuss the role of childbirth preparation as a way to enhance beta-EP secretion. Levels of ACTH, on the other hand, appear to be more closely related with behavior during labor, regardless of whether the mother received preparation.

Small intestinal sulphoxidation of albendazole

1. The in vitro sulphoxidation of Albendazole (ABZ) by rat intestinal microsomes has been examined. The results revealed intestinal sulphoxidation of ABZ by intestinal microsomes in a NADPH-dependent enzymatic system. The kinetic constants for sulphoxidase activity were Vmax = 46 pmol/min/mg protein and Michaelis constant Km = 6.8 microM. 2. The possible effect of inducers (Arochlor 1254 and ABZ pretreatment) and inhibitors (erythromycin, methimazole, carbon monoxide and fenbendazole), was also studied. In rat pretreated with Arochlor 1254, Vmax was 52 pmol/min/mg protein, whereas oral administration of ABZ increased the intestinal sulphoxidation of the drug, Vmax being 103 pmol/min/mg protein. 3. Erythromycin did not change the enzymatic bioconversion of ABZ, but methimazole and carbon monoxide inhibited the enzyme activity by approximately 60 and 30% respectively. Fenbendazole (a structural analogue of ABZ) was a competitive inhibitor of the sulphoxidation process, characterized by a Ki or 69 microM. 4. These data demonstrate that the intestinal enzymes contributing to the initial sulphoxidation of ABZ may be similar to the hepatic enzymes involved in the biotransformation process by the P450 and FMO systems, a conclusion that needs to be further established.

Influence of ethanol on gastric absorption and metabolism of albendazole and mebendazole

The effect of ethanol administration on gastric absorption in rats of two benzimidazole derivatives has been studied. The ethanol administration was carried out as both acute (5%, 10% and 15% w/v of ethanol in the perfusion solution), and chronic (15, 30 and 120 days) forms. Two benzimidazole derivatives were used: albendazole (ABZ) and mebendazole (MBZ). The administration of ethanol did not affect the kinetic mechanism of the absorption process (simple diffusion) but the absorption rate decreased in all treatments except in 5% acute ethanol, presumably due to the improved solubility of the drugs. Plasma, bile and liver levels after gastric perfusion suggest a possible interference of ethanol metabolism with drug hepatic metabolism.

Plasma levels of beta-endorphin and ACTH during labor and immediate puerperium

We measured concentrations of beta-endorphin (beta-EP) and adrenocorticotropic hormone (ACTH) in maternal peripheral plasma during dilation, the expulsive period and immediate puerperium, and in the umbilical vein. Plasma levels of both peptides increased markedly and were directly correlated during labor, and decreased 24 h after birth; they were no longer correlated during immediate puerperium. In the umbilical vein, beta-EP and ACTH were also directly correlated. Moreover, the concentration of each of the two peptides in maternal plasma during the expulsive period was correlated with the corresponding concentration in umbilical vein. We discuss the importance of placental corticotropin-releasing factor in the regulation of maternal and fetal stress.

Albendazole and mebendazole uptake by isolated enterocytes

Uptake of albendazole (ABZ) and mebendazole (MBZ) by isolated rat enterocytes was carried out. These drugs, widely used oral anthelmintics, exhibit a scarce water solubility which reduce its absorption by the oral tract. The present study was designed to assess the captation for ABZ and MBZ in different enterocyte populations isolated from upper to crypt villus. The concentration range used for the absorption experiments was within 10-500 microM for both drugs, using DMSO as solvent. The results obtained show the existence of a passive mechanism for the uptake of ABZ and MBZ at concentrations between 10 and 100 microM, with a maximum intake value around 20 microM/mg protein. No differences were found with respect to the cell populations analyzed. The drug uptake levels seem to be higher for MBZ than for ABZ prior to reaching the maximum plateau.

Inhibition of calcium entry induced by cularines and isocrasifoline in uterine smooth muscle

The effects of nifedipine, papaverine and four benzylisoquinoline alkaloids (cularine, cularidine, celtisine and isocrasifoline) were studied in isolated rat uterus in order to clarify the mechanism of their relaxant action. All the compounds tested completely relaxed KCl-induced contractions and totally or partially inhibited oxytocin-induced rhythmic contractions. Only papaverine acted intracellularly, promoting relaxation of contractile responses induced by oxytocin or vanadate in a Ca(2+)-free medium. In spite of the structural relationship between papaverine and the other alkaloids, the mechanism of their relaxant action is not the same. The activities of cularine derivatives and of isocrasifoline were similar to that of nifedipine.

Stable biomembrane surfaces formed by phospholipid polymers

Phospholipids (phosphatidylcholines) with diacetylene in each acyl chain have been deposited in Langmuir-Blodgett multilayers on a variety of substrates. Upon irradiation the diacetylene groups polymerise and link the phospholipid molecules together with a conjugated chain made up of alternating single, double and triple bonds. Advantage has been taken of this polymerisation process to increase the stability of these lipids layers and to produce stable biomembrane hydrophilic surface. These surfaces may be useful for studies of blood coagulation and protein adsorption. In addition they could also have medical application.

II - Low Molecular Weight Urokinase (UK) and Different Molecular Weight Heparin (Hp) Fractions in Fibrinolysis

We have studied the effect of HMW and LMW Hp on the rat blood LMW-UK activated. Inhibitors of fibrinolysis were evaluated by our method on fibrin activated plate (Throrab. Haem. 38, 283, 1977) and the chromogenic substrate S-2251 and fibrinolytic activity by eugLobulins. The studied dosages were of 100 - 300 P1.U/ml for LMW-UK and from 0.001 to 1,000 I.U/ml for both heparins. The reduction of Inhibitory activity brought about by LMW-UK was not altered by low HMW-Hp dosages, but hihg ones suppressed the diminishing effectinduced by LMW-UK. The activation produced by LMW-UK in euglobulins was increased with low dosages of HMW and LMW Hp whereas high dosages produced a marked Inhibition (highly significant). The inhibitory effect of Hp at high dosages was not related to the molecular variations of UK or Hp. Fundamen tal differences attributed to Hp were not found, but HMW-UK produced greater activity in euglobulins and greater decrease in inhibitors levels than LMW-UK. These results show that Hp at high levels (above 10 I.U/ml) potentiate the UK inhibitors.

I - High Molecular Weight Urokinase (UK) and Different Molecular Weight Heparin (HP) Fractions in Fibrinolysis

Following our previous works on the interaction of UK and Hp (Thromb. Haem, 38, 105, 1977), we have carried out research to clarify the possible influence of the specific molecular weights characteristics in that interaction, We have studied the relationship of HMW-UK (54,000) to HMW and LMW Hp in rat blood. Inhibitors were evaluated by chromogenic substrate 5-2251 and by our method on an activated fibrin plate, and fibrinolysis by euglobulins. The HMW-UK was tested in a dosage range of 100 to 300 PI.U/ml and Hp ones were: from 0.001 to 1,000 I.U/ml. Hp did not alter the basal inhibitor levels measured on fibrin substrate but we obtained on synthetic substrate an inhibition of 12% on the basal value for all Hp dosages. HMW-Hp produced an increase in the fall of the inhibitory activity induced by HMW-UK for low dosages of Hp, whilst high dosages produced an increase of inhibition, suppressing the UK indeed reduction of inhibitor levels. For LMW-Hp the low dosages did not alter the UK effect while high ones imppreased it. Euglobulins activity HMW-UK induced were not modified by low dosages but high ones induced a highly significant inhibition (for both Hp fractions).